editorial board

AFRICAN JOURNAL OF ANAESTHESIA AND INTENSIVE CARE Journal of the Societies of Anaesthetists of West and East Africa VOLUME 12

NO. 1

JUNE 2012

ISSN0794–2184

The African Journal of Anaesthesia and Intensive Care is owned by the Society of Anaesthetists of West Africa and the East African Societies of Anaesthetists.

EDITORIAL BOARD EDITOR-IN-CHIEF PROF. S.D AMANOR-BOADU EDITORS Prof. S.G Akpan Prof. O.T Kushimo Prof. Stella Eguma Dr. O.O Oladapo Prof. Gladys Amponsah Dr. E. Aniteye

EDITORIAL ADVISERS Prof. O.A Soyanwo Prof. Akin Osibogun OVERSEAS EDITORIAL ADVISERS Dr. I. H. Wilson (UK) Dr. Paul Clyburn (UK) EDITORIAL TECHNICAL BOARD Dr. A.S Lawani-Osunde Dr. Shina Ogunbiyi Dr. I. Desalu AIMS: The aims of the African Journal of Anaesthesia and Intensive Care are: 1. 2. 3. 4.

To provide a medium for the international dissemination of information about Anaesthesia, Intensive Care and related disciplines in Africa and elsewhere. To serve as a forum for publications relating to International Conference on Anaesthesia, Intensive Care and related disciplines in West and East Africa. To promote co-operation amongst Anaesthetists, Intensive Care Physicians and Medical Scientists in related disciplines in Africa. To furnish a means whereby appropriate international and health organization may transmit information to Anaesthetists, Intensive Care Physicians and Medical Scientists in related disciplines throughout Africa. i

INSTRUCTIONS TO AUTHORS Mission statement The purpose of the African Journal of Anaesthesia and Intensive Care is the publication of original work in Africa and other parts of the world in all branches of anaesthesia and intensive care including the application of basic sciences. It is a peer-reviewed journal and is published twice a year.

The Editor-in-Chief African Journal of Anaesthesia and Intensive Care c/o Department of Anaesthesia, Lagos University Teaching Hospital P.M.B 12003, Lagos, Nigeria Email: [email protected] The manuscript must be typed on MS-word, doublespaced on one side of a standard A4 paper with at least 25mm margin on each side. Text, Tables and Figures should be on separate sheets. Manuscripts must conform to acceptable English language and authors must employ clear scientific writing. Standard abbreviations may be used but only after their full meaning have been indicated in an earlier portion of the text. All measurements must be in SI units. Patients should be referred to by number or letters only; names, initials or hospital record number must not be used. The eyes must be masked on any photograph of a patient showing the face; otherwise such a photograph must be accompanied by a statement of consent signed by the patient.

Professional and Ethical Responsibilities Before a manuscript is sent for publication, the corresponding author must seek the permission from all co-authors. Authorship should be limited to those persons who have contributed to the intellectual content of the article. Percentage contribution of each author may be indicated. Papers submitted should be accompanied by a declaration that no substantial part has been or will be submitted or published elsewhere. This does not refer to abstracts of oral communications which are printed in proceedings. It is a condition of acceptance for publication that copyright becomes vested in the journal and permission to republish must be obtained from the editor. Authors must indicate that studies were approved by their institutional Ethical committees in conformity with the Helsinki Declaration 1975(as amended)

The onus of preparing a paper in a suitable form for publication will rest on the author/s.

Categories of Contribution Original article – original research article on any aspect of anaesthesia and intensive care. Abstract should not be more than 250 words and the body of the article not more than 2500 words.

Format: The manuscript should consist of (i) title page, (ii) summary, (iii) text, (iv) acknowledgements (v) references (vi) table, (vii) figures, all numbered consecutively. Each component should begin on a new page in the sequence given above.

Review article – detailed, systematic and critical evaluation of literature on a specific topic. Maximum of 5,000 words.

Title page: Should include the title of the manuscript, the name, qualification and full address of each author, the name, address and email address of the corresponding author and up to six key words. Title should be short, specific and clear.

Short communication – Short reports on original research not exceeding 1500 words, 2 tables or figures and a maximum of 10 references.

Summary: This should contain not more than 250 words structured as follows (i) Background, (ii) Patients and Methods, (iii) Results, (iv) Conclusion. Unstructured summaries may be submitted for case reports. Summaries are not necessary in Editorials and Letters to the editor.

Case Report – Case report of interesting and unusual cases. Letter to the editor- Comments on materials previously published in the journal, clinical observations or other matters relevant to anaesthesia and intensive care. Letters should contain a maximum of 750 words and 2 tables/ figures.

Text: The main text should be divided into (i) Introduction, (ii) Patients and Methods, (iii) Results, (iv) Discussion, (v) Conclusion, (vi) Acknowledgements, (vii) References. References References should not exceed 20 – 25 in number and should preferably be limited to the last decade. They should be identified in the text by superscript Arabic numerals. The references should be arranged according to the Vancouver style. All authors should be listed, but however if more than five, list five followed by et al.

Conference, Seminar and Workshop reports – Manuscript Preparation The original soft and three hard copies of the manuscript and all supporting materials including a covering letter signed by the corresponding author must be submitted to the Editor-in-Chief and addressed to ii

(1)

(ii)

TABLE I. Age and sex distribution of medical undergraduates

For journal articles, give surname and initials of author, article title, name of journal, year of publication, volume number and first and last pages. e.g (i) Sanusi AA, Soyannwo OA, Amanor-Boadu SD. Intra-operative cardiac arrest. West Afr J Med 2001; 20: 192-195. Merah NA, ffoulkes-Crabbe DJO, Kushimo OT, Bode CO. Modified Mallampatti test, thyromental distance and inter-incisor gap are the best predictors of difficult laryngoscopy in West Africans. Can J. Anaesth 2005; 52: 291 –296.

2)

For authors of books, give surname and initials of all authors, title of book, Edition, City, Publisher, year and pages. e.g Famewo CE. Lectures in Anaesthesia & Intensive care. 3rd Edition, Ibadan. Lovemost Printers. 2004 :21-27.

3)

For authors of a chapter in a book, give surname and initials of all authors of the particular chapter, title of chapter, Editors of the book, title of the book, Edition, City, Publishers, year and pages. e.g Nageder SB. The Acute Abdomen. Badoe EA, Archampong EQ, da Rocha-Afodu JT( editors) Principles and Practice of Surgery including Pathology in the tropics, 3rd Edition, Tema, Ghana Publishing Corporation. 2000: 503-508.

Age (yr)

Male No (%)

Female No (%)

Total No (%)

21-25 26-30 31- 35 Total

41 (48.2) 45 (70.3) 5 (83.3) 92 (59)

44 (51.8) 19 (29.7) 1 (16.7) 64 (41)

85 (100) 64 (100) 6 (100) 156 (100)

be numbered with pencil lightly on the back indicating the top and should be accompanied by a suitable legend Figures should be titled and numbered with Arabic numerals (1,2,3…..) and should be referred to in the text in the appropriate position. Tables should be self-explanatory and numbered in Roman numerals (I, II, III……) and should include titles which make their meaning clear without reference to the text. Tables should be easy to read. Table format should be as followsReview Process Manuscripts submitted for publication will initially undergo internal review for its suitability. An acknowledgement of receipt of all manuscripts will be sent to the corresponding author. Thereafter if the manuscript is found to conform to the scope of the journal, it will then undergo a blinded peer review by at least two assessors. The assessors’ judgment on suitability of manuscript, corrections and comments will then be communicated to the corresponding author. The editorial board will meet to decide on all corrected manuscripts before letters of acceptance or rejection are sent to the authors.

Illustrations, Tables and Figures Illustrations, figures and tables should be few and relevant.Photographs must be submitted as glossy prints, untrimmed and unmounted. Each photograph must

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AFRICAN JOURNAL OF ANAESTHESIA AND INTENSIVE CARE Journal of the Societies of Anaesthetists of West and East Africa VOLUME 12

NO. 1

JUNE 2012

ISSN0794–2184

Table of Contents Editorial Board Instructions to Authors Contents

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i ii iv

Awareness under Anaesthesia: A review of patients following General Anaesthesia at a tertiary hospital in Nigeria – O. R. Eyelade, A. A. Sanusi., T. A. Adigun, S. D. Amanor-Boadu .... ...

1–5

Right Heart Catheterisation in Patients with Echocardiographic Diagnosis of Pulmonary Hypertension – E. Aniteye, F. Edwin, M. Tettey, H. Baddoo, E. Ofosu-Appiah, L. Sereboe, D. Kotei, M. Tamatey, K. Entsuah-Mensah, M. Adadey, A. Doku, Y. Cruz... ...

6– 10

ORIGINAL ARTICLES

Spinal Anaesthesia for Appendectomy: Experience at the University of Benin Teaching Hospital (UBTH), Benin-City, Edo State, Nigeria – M. O. Osazuwa, J. M. Afolayan, N. P. Edomwonyi ... ...

11 – 15

Anaesthesia for Surgical Outreach in a Rural Nigerian Hospital – I. U. Ilori ...

16 – 20

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Comparison of Caudal analgesia and Intravenous Diclofenac for postoperative pain relief in paediatric patients undergoing Daycase Herniotomy. – B. K. Aroso, I. D. Menkiti, M. A. Akintimoye, O.I.O. Dada, I. Desalu, O. T. Kushimo ...

21 – 26

Comparative Effects of Intrathecal Midazalam and Bupivacaine Combination with Bupivacaine alone for Spinal Anaesthesia in Gynaecological Procedures. – S. Sidiq, S. Gurcoo, M. Sadiq, S. Aleem ... ... ...

27 – 29

COMING EVENTS NEWS

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30

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31

iv

Awareness under Anaesthesia: A review of patients following General Anaesthesia at a Tertiary Hospital in Nigeria

O. R. EYELADE, A. A. SANUSI, T. A. ADIGUN, S. D. AMANOR-BOADU Department of Anaesthesia, College of Medicine, University of Ibadan/ University College Hospital, Ibadan, Nigeria.

ABSTRACT Background: Awareness and recall of surgical events under general anaesthesia is an uncommon adverse effect that may result in psychological distress for the patient. This prospective review of cases was performed to evaluate the incidence of awareness and recall during general anaesthesia in a surgical population at the University College Hospital, Ibadan. Patients and Methods: A prospective audit was conducted over a period of 10 months using open ended questionnaire administered within 24 – 36 hours postoperatively to patients who had surgical procedures under general anaesthesia. The anaesthetic record of each patient that had awareness and recall was reviewed to search for data that might explain the awareness episode. Results: A total of 1,185 patients were visited in the postoperative period. Nine hundred and fifty-five patients (80.6%) had general anaesthesia while 230 patients (19.4%) had other forms of anaesthesia (regional anaesthesia or conscious sedation). Of the 955 patients (479 males and 476 females) that had general anaesthesia, 7 (5 females and 2 males) patients reported occurrence of awareness during the operation with recall of intra-operative events, the incidence of awareness was 0.7%. Identified risk factors in patients who reported awareness include lack of amnesic premedication, light general anaesthesia as a result of sub-optimal doses of hypnotic agents and failure to administer supplemental doses of analgesic intra-operatively. Conclusion: The incidence of awareness with recall in this prospective review was 0.7%, light anaesthesia being the major predisposing factor. Use of amnesic premedicants, monitoring of end tidal volatile agent concentration and intraoperative supplementation of analgesia may reduce the occurrence of awareness under general anaesthesia. Keywords: General anaesthesia, Complications of anaesthesia, Awareness, Audit INTRODUCTION Awareness under general anaesthesia is a phenomenon that tends to occur when consciousness is not fully depressed in a patient who is expected to be deeply unconscious. There are various definitions for this phenomenon, however, it would suffice to simply state that awareness under anaesthesia could be implicit and remain hidden in the subconscious level or explicit when the individual is able to remember intra-operative events when asked.1,2 It could be assumed that the use of balanced anaesthesia technique in modern practice of general anaesthesia should reduce the risk of awareness in the surgical population. This assumption is based on the working principles of balanced anaesthesia technique where hypnotics are employed to produce deep

*Correspondence: Dr Olayinka R. Eyelade, Department of Anaesthesia, College of Medicine, University of Ibadan / University College Hospital, Ibadan, Nigeria. Tel No: +234-8058978580 E-mail: [email protected]

unconsciousness, analgesics to provide pain relief and muscle relaxants are administered to prevent reflex movements to surgical stimulation. However, this assumption is only valid to an extent as most cases of awareness had been observed to occur under light anaesthesia.3 In general, the incidence of awareness varies between 0. 1% and 0.2% .1, 2 Awareness is a major cause for concern in patients presenting for surgery under general anaesthesia with 25.8% of surgical population in a Nigerian tertiary hospital expressing this worry as ‘waking up during surgery.’4 Previous studies have also established that awareness under anaesthesia could lead to a form of post-traumatic stress disorders (PTSD) ranging from unpleasant dreams and agonizing recall of the trauma, to sleep disturbances, irritability and outburst of anger.5 In addition, being aware under anaesthesia could be a major cause of litigation against anaesthetists as shown in a closed claim analysis in the United State of America (USA).6 It is postulated that incidences of awareness do occur in the Nigerian patients as alluded to in a recent editorial on a letter written by an anaesthetist who was aware while undergoing caesarean

African Journal of Anaesthesia and Intensive Care, Vol. 12, No. 1, June 2012

1

AWARENESS UNDER ANAESTHESIA

section under general anaesthesia.7 The psychological effects of awareness could be debilitating and therefore it is of utmost importance to evaluate the incidence of awareness in the Nigerian surgical patient population. This prospective review was therefore carried out to evaluate the incidence of awareness in an adult surgical population at the University College Hospital, Ibadan. We also identified possible causes of these awareness episodes with a view to proffering suggestions on strategies that could be employed to reduce the risk of awareness under anaesthesia. PATIENTSAND METHODS A prospective audit of post anaesthesia complications was conducted over 10 months (January – October 2010) at the University College Hospital, Ibadan, Nigeria using an open ended questionnaire. Participants were in-patients of the hospital who had operation at the Main Operating Theatre Suites. The questionnaire was administered within 24-36 hours postoperatively to patients who had surgery under general anaesthesia.The preoperative and anaesthetic record of patients that had awareness were reviewed to identify the probable predisposing factor(s). Exclusion criteria included age less than 16 years, communication difficulties, caesarean section operation, day-case surgery, and postoperative admission into the intensive care unit. Patient interview and Definition of awareness Data was collected using a structured questionnaire administered by trained medical officers in the postoperative period. Information requested on the questionnaire included the patients’ demography, preoperative status and premedication, type of operation and length of surgery. Other information obtained included technique of anaesthesia, intra-operative analgesia and maintenance technique, a list of possible post-anaesthetic complications (sore throat, vomiting, jaundice, awareness, headache, neurological impairment, inadequate pain control and others) which required ‘Yes’or ‘No’ answers. The patients who answered ‘Yes’ to awareness were revisited on the 5th postoperative day when it was assumed that they would be more lucid to provide more information on the episode of the awareness and for the interviewer to be sure of the incidence. We defined ‘Awareness’ as ability to remember intraoperative events with recall of these events (AWR) including auditory or pain perception. Patients who had awareness with recall received psychological counseling and support provided by a Consultant Anaesthetist. Because this audit was performed as part of a quality assurance programme rather than a study on awareness ab initio, we did not use the Brice questionnaire8 which was developed to identify the presence of intra-operative

2

awareness in adults. Evaluation of Possible Predisposing Factor The anaesthetic charts of patients who had AWR were reviewed with a view to identifying probable risk factor(s). These risk factors include misjudgment of the amount of anaesthetic to keep patient unconscious, malfunctioning of anaesthetic equipment, patient related factors such as unstable haemodynamic; procedure related factors such as cardiac or trauma surgery and use of muscle relaxants.7 Light anaesthesia is said to have occurred in this study if the anaesthetist had use suboptimal dose of induction agent or turned off the volatile anaesthetic agent during maintenance of anaesthesia with no supplementation of hypnotic or analgesic agent. In addition, the description of the awareness episode provided by each patient was documented. Anaesthetic technique All the patients under this review had either general anaesthesia and airway maintenance was either with endotracheal intubation or the use of laryngeal mask airway. Anaesthetics were administered by resident doctors within 3 years of their training in anaesthesia under the supervision of Consultant Anaesthetists Analysis Analysis was conducted using qualitative method. The description of the awareness experienced by each patient with AWR were noted and written down by the investigating medical officer and discussed with one of the authors who provided psychological counselling and support. We used content analysis to summarize the description of the patients’ awareness experience Results A total of 1185 patients were visited in the postoperative period and interviewed by the medical officers. Of this number, 955 had general anaesthesia (479 males and 476 females) and 230 patients had regional anaesthesia with or without sedation. Of the 955 patients that had general anaesthesia, 7 (5 females and 2 males) experienced awareness with recall of intra-operative events. The incidence of awareness in this population was 0.7% (7/955). Table I shows the demography, type of surgery, anaesthetic details, duration of surgery and description of awareness. The identified possible cause of awareness is documented in the anaesthetic details section. The description of the awareness was summarized in Table II. Auditory perception and inability to move or breathe were the major complaints. Overall, the main risk factors identified in this review were inadequate anaesthesia due to administration of sub-optimal doses of hypnotics, lack of preoperative premedication with amnesic agent and the use of muscle relaxants.


OLAYINKA R. EYELADE ET AL

Table 1: Patients’ characteristics, type of surgery, anaesthetic details, duration of surgery and description of awareness Patient Age No

Sex

Premedication Type of surgery

Anaesthetic Details

Duration of surgery

Description of awareness

1

46yrs

Female (obese)

Diazepam

Cholecystectomy

2 hours

2

35yrs

Female

Nil

Excision of palatal mass

Remembered endotracheal tube in her throat, could not breathe Recalled surgeon working in her mouth, no pain

3

73yrs

Male

Nil

Exploratory laparotomy

4

40yrs

Female

Diazepam

Total abdominal hysterectomy (TAH)

5

25yrs

Female

Nil

Excision of jaw tumour

6

48yrs

Male

Nil

Wound debridement

7

22yrs

Female

Diazepam

Evacuation of molar pregnancy

Propofol/fentanyl/ pancuronium/ halothane 0.5% (Light anaesthesia) Thiopentone/fentanyl/ pancuronium/ isoflurane 1%(Light anaesthesia) Propofol/Rapid Sequence Induction/fentanyl/pancuronium/ Halothane 1.2% (No supplemental analgesia) Thiopentone/Rapid Sequence Induction/fentanyl/pancuronium/ halothane 0.7% (No supplemental analgesia) Propofol/fentanyl/ pancuronium/isoflurane 1%(Had difficult Intubation) Propofol/fentanyl/paracetamol/ pancuronium/isoflurane 1% (Light anaesthesia) Thiopentone/Rapid Sequence Induction/fentanyl/pancuronium / isoflurane 1% (Light anaesthesia)

Key: mins - minutes, hr – hour;

30 mins

1hr 45mins

Recalled hearing undiscernable noises

3 hrs

Remembered feeling endotracheal tube in her throat, wanted to speak, could not move

6 hrs

40 mins 1 hr

Remembered waking up in the middle of surgery and could not move Remembered surgeon working on his back, could hear people speak, could not move. Felt pain Remembered waking up and could not breathe or move. Heard noises

hrs – hours; yrs - years

Table II: Summary of the description of Awareness (N=7) Description

n

%

Unable to move/speak Auditory Perception Sensation of Endotracheal tube Pain

4 3 2 1

57.1 42.9 28.6 14.3

More than one description in a patient hence, the total is more than 100%

Discussion Awareness is an uncommon adverse side effect of general anaesthesia. The first report of the phenomenon was in 1950 in the United Kingdom (UK)9 and several reports came from the UK, the Scandinavia countries and the USA thereafter.5, 6 In this review, the incidence of awareness with recall was 0.7% in a Nigerian population compared to 0.1 – 0.2% reported in current literature.2,5,10 However, this finding is consistent with that of Ranta and colleagues11 who reported an incidence of 0.4 – 0.7%. Despite the high incidence observed in this report, it is possible that some cases of possible awareness had been missed because we did not assess long term effect of awareness and our follow up was limited to the 5th postoperative day. A previous study had demonstrated that approximately 35% of cases are detected only at a delayed postoperative interview. 12 This observation underscores the importance of postoperative visits by anaesthetists. Controversy exists regarding the timing of interview in this type of study. Some authors had suggested the interview taking place soon after the patient awakens14 while others preferred days or weeks postoperatively so

that vivid description could be obtained.2 In addition, follow up for weeks or months after surgery allowed for detection and treatment of psychological sequelae.1,5 Awareness may be complicated by a spectrum of psychological symptoms ranging from anxiety, fear of surgery, sleep disturbances to flash backs, nightmares and post traumatic stress disorder or depression. However, we did not evaluate the psychological effects of the awareness in this patient population. Nonetheless, except for sleep disturbances, post traumatic stress disorder has been reported to be uncommon in patients with awareness and recall.1, 5, 11 Awareness has been postulated to be more common in young patients and in women2,5 hence we were not surprised that over 70% of the cases of awareness in this review were women (5/7). The reasons advanced for this observation include the fact that women tend to recover faster from general anaesthetics due to pharmacokinetic differences.14,15 In addition, women tend to report incidence of dreaming during anaesthesia.1 Obesity is another factor that could contribute to a higher risk of awareness because it makes it difficult to estimate the pharmacokinetics of the anaesthetic. One of the patients in this cohort was a female presenting for cholecystectomy and noted as being obese, though the weight (or better the BMI) was not provided. Most cases of awareness reported in the literature have been directly linked to overtly light anaesthesia. Light anaesthesia could be as a result of technical errors by the anaesthetist, equipment failure (vaporizer being empty or not properly fitted to the machine) or patient related’ when anaesthetics are deliberately reduced to protect the patient’s cardio-respiratory function. In this review, light anaesthesia was a major factors in all the cases reviewed.


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AWARENESS UNDER ANAESTHESIA

Administrations of sub-optimal doses of induction agent, failure to administer supplemental analgesic were possible technical errors on the part of the anaesthetists. It is noteworthy that resident anaesthetists within the first 3 years of training were involved in the management of these patients. Although, these residents were under the supervision of Consultant anaesthetists, failure to apply knowledge or lack of depth of knowledge might account for the technical errors noted. Adequate training and retraining of anaesthetic personnel would ensure that they remained competent and are able to deliver optimal services, protecting patients and ensuring quality postoperative outcome. Use of muscle relaxant has been shown to predispose to increased risk of awareness particularly when consciousness has not been adequately depressed during surgery.8,11 All the cases in this report had non depolarising muscle relaxant administered. When muscle relaxants are used, it is imperative that the anaesthetist maintains a high anaesthetic gas concentration to ensure that the patient remains unconscious. In this study, auditory perceptions and muscle paralysis were the main effects reported by the patients who had AWR (Table II). Monitoring of effective volatile anaesthetic concentrations (expired MAC of volatile anaesthetics) has been found to be valuable at reducing the risk of awareness.16 Use of small doses of hypnotic or amnesic agent such as midazolam, ketamine, diazepam, propofol can be employed when the use of high concentration of volatile anaesthetic agent is adjudged to be unsafe. Nitrous oxide, used to be a valuable second gas in inhalational anaesthesia; however, modern anaesthetic practice is excluding nitrous oxide due to environmental reasons. One literature reviewed had shown that the presence or absence of nitrous oxide seem to have no influence on the incidence of awareness phenomenon.5 Measurement of adequate depth of anaesthesia is difficult in most cases because brain function monitoring is often judged indirectly using surrogate markers such as movement under anaesthesia, changes in blood pressure and heart rate. However, a study on awareness in the USA10 had shown that these surrogate markers have limited value. Other attempts at monitoring brain function under anaesthesia include the use of electroencephalogram (EEG) and the bispectral index (BIS).17,18 The BIS monitor is a processed EEG derivative that assigns a numerical value to the probability of consciousness. Recovery of consciousness during general anaesthesia without any recall (in the absence of surgical stimulus) has generally been associated with BIS values of 60 or less. Ekman and colleaguesl7 investigated the incidence of awareness when the anaesthetic was guided with BIS and found a 77% reduction in the incidence of awareness while Myles et al found 82% reduction. 18 The cost of this monitoring equipment may preclude their use in developing countries such as Nigeria. The onus is therefore on the anaesthetist 4

to develop his/her clinical acumen and maximise the use of surrogate markers such as movement under anaesthesia, sweating, lacrimation and rise in blood pressure and heart rate. Conclusion The incidence of awareness with recall in this study was 0.7% comparable to the findings of other authors. The main predisposing factor being light anaesthesia. Training of anaesthetic personnel should include appropriate use of inhalational and intravenous anaesthetic agents, clinical monitoring of depth of anaesthesia and the use of appropriate depth monitor where available. Acknowledgement We acknowledge the contribution of Dr O.O. Jaiyeoba, Dr O.A. Ademua, Dr O.O. Adigun and Dr S.O. Ojediran who helped with the data collection and did the postanaesthetic visits. REFERENCES 1.

Bischoff P., Rundshagen I: Awareness during general anesthesia. Dtsch Arztebl Int 2011; 108(1–2): 1–7. DOI: 10.3238/arztebl.2011.0001. (Article in English Language. Accessed from www.ncbi.nlm.nih.gov/pmc/articles/ PMC3026393/pdf on December 11, 2011. 2. Errando C. L., Sigl J. C., Robles M., Calabuig E., Garcý´a J. et al. Awareness with recall during general anaesthesia: a prospective observational evaluation of 4001 patients. Br J Anaesth 2008; 101: 178–85. 3. Nickalls R. W. D., Mahajan R. P., Editorial – Awareness Br J Anaesth 2010; 104: 1–2. 4. Eyelade O. R., Akinyemi J. O., Adewole I. F. Risks associated with Anaesthesia; Patients’ knowledge and concerns. Afr J Anaes Int Care 2009; 9(1): 5 – 7. 5. Ghoneim M. M., Block R. I., Haffarnan M., Mathews M. J. Awareness during anesthesia: risk factors, causes and sequelae: a review of reported cases in the literature. Anesth Analg 2009; 108: 527–35. 6. Domino K. B., Posner K. L., Caplan R. A., Cheney F. W. Awareness during anesthesia: A closed claim analysis. Anesthesiology 1999; 90(4): 1053–61. 7. Imarengiaye C. O. Editorial - Awareness under General Anaesthesia: No Exemption, Not Even an Anaesthetist. Afr J Anaes Int Care 2011; 11(2): v-vi. 8. Brice D. D., Hetherington R. R., Utting J. E. A simple study of awakeness and dreaming during anaesthesia. Br J Anaesth 1970; 42: 535-542. 9. Winterbottom E. H. Insufficient anaesthesia. Br Med J 1950; 1: 247–8. 10. Sebel P. S., Bowdle T. A., Ghoneim M. M., Rampil IJ, Padilla R. E et al. The incidence of awareness during anesthesia: a multicenter United States study. Anesth Analg 2004; 99: 833–9. 11. Ranta S. O. V., Laurila R., Saario J., Ali-Melkkila T., Hynynen M. Awareness with recall during general anaesthesia. Anesth Analg 1998; 86: 1084-9. 12. Sandin R. H., Enlund G., Samuelsson P., Lennmarken C. Awareness during anaesthesia: a prospective case study. Lancet 2000; 355: 707–11.


OLAYINKA R. EYELADE ET AL

13. Ghoneim M. M., Block R. I. Learning and consciousness during general anaesthesia. Anesthesiology 1992; 76: 279 – 305. 14. Gan T. J., Glass P. S., Sigl J., Sebel P., Payne F. et al. Women emerge from general anesthesia with propofol/ alfentanil/nitrous oxide faster than men. Anesthesiology 1999; 90:1283–7. 15. Hoymork S., Raeder J. Why do women wake up faster than men from propofol anaesthesia. Br J Anaesth 2005; 95: 627–33.

16. Avidan M. S., Zhang L., Burnside B. A., Finkel K. J., Searleman A. C. et al. Anesthesia awareness and bispectral index. N Engl J Med 2008; 358: 1097–108. 17. Ekman A., Lindholm M. L., Lenmarken C., Sandin R. Reduction in incidence of awareness using BIS monitoring. Acta Anaesthesiol Scand 2004; 48: 20 -6. 18. Myles P. S., Leslie K., McNeil J., Forbes A., Chan M. T. et al. Bispectral index monitoring to prevent awareness during anaesthesia: the B-Aware randomised controlled trial. Lancet 2004; 363: 1757–63.


5

Right Heart Catheterisation in Patients with Echocardiographic Diagnosis of Pulmonary Hypertension

E. ANITEYE1, F. EDWIN2, M. TETTEY2, H. BADDOO1, E. OFOSU-APPIAH1, L. SEREBOE2, D. KOTEI1, M. TAMATEY2, K. ENTSUAH-MENSAH2, M. ADADEY3, A. DOKU3, Y. CRUZ3. 1

Anaesthetist, 2Surgeon, 3Cardiologist, National Cardiothoracic Centre, Korle-bu Teaching Hospital, P.O Box KB 846, Korle-bu Accra, Ghana

ABSTRACT Background: Anaesthetists and other clinicians depend on echocardiographic estimation of pulmonary artery pressures for clinical decisions in cardiac patients. Our objective was to compare the systolic pulmonary arterial pressures estimated by echocardiography to that measured by right heart catheterisation. Patients and Methods: This was a retrospective-prospective analytical study of all patients referred for right heart catheterisation (RHC) between 1st January 2006 and 31st March 2010. The echocardiographic (Echo) estimation of the systolic pulmonary artery pressures was compared to the systolic pulmonary artery pressures measured during right heart catheterisation. Results: There were 64 patients, 37 (57.8%) were female, 27(42.2%) male. Twenty (31.3%) were between 11-20 years and 13 (20.3%) were 31-40 years. The youngest patient was 3 years old and the oldest 68 years. The Echo diagnosis was ASD, VSD, and Pulmonary Arterial Hypertension in 32.8%, 21.9% and 12.9% respectively. The right internal jugular vein was used in 58(90.6%) and the right femoral vein in 6(9.4%). Thirty-three (51.6%) had RHC systolic pressure greater than 35mmHg. Overall there was an inaccuracy of 69.8% for pressure measured by Echo. Echo was accurate in only 31.1% of instances in patients with congenital heart disease and inaccurate in all patients with rheumatic heart disease. Conclusion: Differences exist between pressures measured by Echo and RHC. Clinically, these differences may to lead to inappropriate management of patients. RHC is therefore necessary in patients with significant pulmonary hypertension especially for congenital and rheumatic heart diseases. Keywords: Echocardiography, Right heart catheterisation, Pulmonary hypertension.

INTRODUCTION Pulmonary hypertension (PH) is characterised by a progressive increase in pulmonary vascular resistance (PVR), due to an increase in the vascular tone from vascular modeling. Eventually there is increased pressure causing right ventricular failure and death 1,2. The normal systolic pulmonary artery pressure (sPAP) at rest is 18-25 mmHg with a mean pulmonary artery pressure (mPAP) of 12-16 mmHg. An increase in pulmonary blood flow and PVR results in pulmonary hypertension. Numerically, this is translated to a mPAP >25 mmHg, or sPAP >35mmHg 3. Accurate determinations of sPAP are critical for both the diagnosis and management of patients with PH. Right heart catheterization (RHC) remains the gold standard for determining PAP. In the West African sub-region, the availability of Echocardiographic (Echo) Doppler has led to the increasing use of Echo as a tool for determining *Correspondence: Dr Ernest Aniteye National Cardiothoracic Centre, P.O Box 846, Korle-bu, Accra, Ghana. E mail:[email protected] 6

sPAP in suspected PH. Echocardiographically, the basis for the measurement of PAP is the velocity of the tricuspid regurgitation jet, pulmonary acceleration time, right ventricular (RV) ejection time, pulmonary regurgitation and the isovolumic relaxation time5,6,7. Brendan et al however found out that there was a wide variation in the measured pulmonary artery pressures in normal patients8. The large population of children with congenital heart disease (CHD) in the sub-region is subject to the increasing reliability on echo estimates of sPAP for the determination of operability in late presenters with suspected PH. The accuracy of echo estimates of sPAP in such patients with PH is not certain. Recent studies by Fisher and his colleagues have suggested that echo estimates of sPAP may not be accurate (9). These studies however did not investigate the accuracy of echos PAP in different diagnostic patient populations, a parameter that may influence the results. The present study was performed to investigate the accuracy of echo estimates of PAP in 3 patient populations commonly referred to our institution.


ECHOCARDIOGRAPHIC DIAGNOSIS OF PULMONARY HYPERTENSION

METHODS This was a retrospective-prospective study at the National Cardiothoracic Centre in Accra, Ghana from 1 January 2006 to 31 March 2010. Using the intensive care register, all patients who had RHC were selected and their case records retrieved. The echo diagnosis and the PA pressures estimated by echo were documented. PA pressures were estimated by using the tricuspid regurgitation velocity, right atrial pressures, size and pressure of the inferior venae cavae. Subsequently, all patients who were sent to the intensive care unit for right sided catheterisation were added to the study. Under full monitoring a venous cannula was inserted into the back of the hand in all patients. All the patients were sedated with Midazolam 0.03-0.07mg/kg, 4 had propofol 1mg/kg, 4 had 1ug/kg of fentanyl and 3 paediatric patients had Vecuronium 0.1mg/kg for mechanical ventilation. The right atrium (RA) was cannulated using the right internal jugular vein (RIJV) or the Right femoral vein (RFV) and a 6.5 - 8.5 Fr venous introducer sheath was inserted. The 5.0 Fr 60-110cm pulmonary artery (PA) catheter (Arrow) was flushed with saline under pressure and was inserted into the RA. Using a transducer, tracing and pressure measurements, the catheter was progressively moved from the RA, the RV, to the PA. A sPAP > 35mmHg was considered to be pulmonary hypertension. The data was analysed using the Statistical Package for Social Sciences package (Version 14.0 SPSS Inc., Chicago, USA). The differences in the measured pressures were compared using the students T-test with Fisher correction for unequal data and a Brand Altman analysis. st

st

RESULTS Of the 64 patients who had RHC, 37(57.8%) were female and 27(42.2%) male. Thirty-two (50.0%) were 1130 years (Fig. 1 and 2 below). The youngest was 3 years old and the oldest 68 years, the mean age being 26.7+17.2 years. The Echo diagnoses are shown in figure 3 below. The RIJV used in 58(90.6%) and the RFV in 6(9.4%). Fifty-one percent and 62.5% had Echo and RHC sPAP greater than 35 mmHg respectively. The mean Echo sPAP and Swan sPAP for all the cases were 54.27+20.9 mmHg and 48.05+24.1 mmHg respectively, p=0.454. A Brand-Altman analysis (Table I) however showed that there was an accuracy of 30.2% and therefore 69.8% of the measured values were inaccurate (figure 4). Congenital heart disease There was a significant difference between Echo sPAP (57.65+21.2 mmHg) and Swan sPAP (48.82+24.9mmHg) for CHD and valvular heart diseases, P= 0.004. For patients with CHD with left to right shunts there was a highly significant difference between the Echo PAP (54.55+19.16mmHg) and Swan sPAP (40.97+22.5mmHg), P=0.0005. From table I, Echo overestimates the true sPAP

by as much as 54.7mmHg and underestimates it by as much as 36.5mmHg. Within the clinically accepted range of ±10mmHg (Fig 5), Echo was accurate in only 31.1% of instances in CHD and estimates of sPAP will result in wrong clinical decision-making in 68.9% of cases of CHD. Rheumatic Mitral heart disease Echo overestimates sPAP by 58.1mmHg and underestimates it by 44.7mmHg. Echo was inaccurate in all the 5 (100%) cases investigated. Wrong decision making would affect about 57.1% of patients (Table I) Pulmonary Arterial Hypertension (PAH) / Chronic Thromboembolic Pulmonary Embolism (CTEPH) Only 5 out of the 8 patients diagnosed as PAH had RHC sPAP greater than 35mmHg. Three had normal sPAP of 23, 17 and 28 mmHg. Echo was accurate in 42.9% of cases (Table 1). Complications encountered during catheterisation included ventricular ectopic beats and 2 cases of access haematoma (3.1%). Eighteen patients (28.1%) have had cardiac surgery with one (sPAP=60mmHg) late mortality after 6 weeks from right heart failure.

Figure 1: Age of Patients

Figure 2: Age and sex distribution


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E. ANITEYE ET AL

Pulmonary Arterial hypertension occurs when there is imbalance between thromboxane A and Prostacycline and this has an effect on the small pulmonary arteries . This was confirmed by a study by Christman et al who confirmed that patients with PAH and PH associated with other conditions had more thromboxane and reduced protacycline derivatives in their urine . Histopathologic changes in the pulmonary vasculature that accompany CHD are usually indistinguishable from PAH. The lesions include medial hypertrophy, intimal proliferation, fibrosis, and, in more severe forms, plexiform lesions and necrotizingarteritis . Untreated, most patients with PH progress to irreversible right heart failure. Eisenmenger’s syndrome (ES) may be associated with CHD and about 3-9% of patients with CHD get ES . Research has shown that the commonest congenital heart disease defects seen with PH are VSD followed by ASD and PDA in that order . This was not confirmed by our study where there were more patients with ASD (32.8%), VSD (21.9%) and single atrium (4.7%). PDA cases were just 1.5% of the cases seen. There was an element of selection bias as the majority of the patients were being assessed preoperatively for open heart surgery. Secondly most patients with PDA have ligation before the age of 4 years and may not need RHC. Bousquet et al in their study found that 50% of patients with PH had PAH . Only 12.6% in the current study had PAH and it is possible that patients were not being properly assessed. The mean age of 26.7+17.2 years was surprising as the cohort included a lot of CHD and may indicate more severely ill paediatric patients were not surviving long enough for surgery to be contemplated. The wide variability of the cohort (3-68) year may also have influenced this mean. In our study the RIJV was used as vascular access for most of the RHC with only 6 (9.4%) having the RFV as vascular access. The RFV was used in most of the paediatric patients as cooperation was easier than with access to the RIJV. Gutierrez et al in their study used the RFV in 88.9% of patients who had RHC as most cardiologists do and they had the advantage of using fluoroscopy to show the position of the catheters during measurements . Hoeper et al however in a review of RHC in experienced centres recorded a 72.7% use of the RIJV although most are done under ultrasound guidance . The patients had Midazolam for sedation. However patients who had catheterisation just before open heart surgery were induced with propofol, Midazolam and were paralysed with Vecuronium. Administration of sedatives and analgesics may cause a reduction in the pulmonary artery pressures and this was alluded to by Fisher and his colleagues who measured the pressures without the administration of sedatives . The significant paediatric population in this study made sedation necessary. Sedation with chloral hydrate is used routinely for the 2

(11)

(11)

12

Figure 3: Echocardiographic diagnosis VSD= ventricular septal defect, ASD= Atrial septal defect, MVS= mitral valve stenosis, AS= Aortic stenosis, PPH= primary pulmonary hypertension, APW= Anomalous pulmonary drainage, PE= Pulmonary embolism, A-V= Atrio-ventricular canal, PDA=Patent ductus arteriosus

(13-15)

(13,14)

(13)

(16)

Figure 4: Bland-Altman Plot:(Echo vrs RHC) All Cases.

(17)

(9)

8


ECHOCARDIOGRAPHIC DIAGNOSIS OF PULMONARY HYPERTENSION

paediatric patients as part of the protocol for Echo in our centre. It was interesting that more patients were found with sPAP above 35mmHg with RHC as compared with Echo but the differences between the means although lower with RHC was not significant. Echo had an accuracy of 30.2% and therefore 69.8% of the measured values were inaccurate. However the differences between RHC and Echo sPAP for patients with valvular and congenital heart disease was however very significant, p = 0.004. Echo estimates of sPAP will result in wrong clinical decisionmaking in 68.9% of cases with CHD and all cases of RHD. Differences in sPAP for patients with congenital heart disease measured by Echo and RHC have been seen by many studies (9,18). Arcasoy et al in their study of PH in patients with lung disease found a big disparity between pressures measured by Echo and RHC which affected diagnosis and classification of the severity of PH among their patients (18). Fisher et al in their study to assess the reliability of Transthoracic Echo found that the there was an inaccuracy of about 48% in comparison to RHC with pressures being most often underestimated9. Transthoracic Echo estimates the right ventricular systolic pressure by estimating the pressure gradient between the RV and the RA using a modified form of the Bernoulli equation, 4v2, where v is the peak tricuspid jet velocity9,19-20. The addition of mean right atrial pressure to the peak tricuspid jet velocity gives an accurate noninvasive estimate of sPAP. Studies have shown a good correlation between the sPAP estimated by Echo and RHC but differences do occur (9,20). This was seen in cases of PAH in our study where 3 (37.5%) were wrongly diagnosed by Echo. Other echocardiographic methods of estimating PAP have been investigated and have been recommended as more reliable than the use of the tricuspid regurgitation jet velocity21, 22. RHC allowed the team in the centre to take decisions as to the suitability of patients for corrective surgery. Eighteen patients have had surgery based on the results of the RHC. Because of the relatively high Echo sPAP some patients may have been denied surgery. Limitations of the study include the administration of sedatives, time lapse between Echo measurement and RHC which were all after 7days, small numbers and the retrospective aspects of the study.

improve diagnosis but RHC may still be necessary in certain patients. REFERENCES 1. 2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

CONCLUSION There are differences between sPAP measured by Echo and Swan sPAP in this study. These differences are very significant especially in patients with rheumatic valvular and congenital heart diseases. Significance clinical disagreements also exist between Echo and RHC which might lead to misdiagnosis of certain patients. It may therefore be prudent in controversial cases for patients to have RHC for complete diagnosis and institution of appropriate therapy. Other noninvasive echocardiographic methods of measuring sPAP may

14.

15.

16.

Humbert M. Update in pulmonary arterial hypertension 2007. Am J Respir Crit Care Med 2008; 177: 574–579. Dai S., Ayres N. A., Harrist R. B. et al. Validity of echocardiographic measurement in an epidemiological study: project heart beat! Hypertension. 1999; 34: 236– 241. Simonneau G., Galie N., Rubin L. J. et al. Clinical classification of pulmonary hypertension. J Am Coll Cardiol. 2004; 43: 5S–12S. Barst R. J., McGoon M., Torbicki A., Sitbon O., Krowka M. J., Olschewski H., Gaine S. Diagnosis and differential assessment of pulmonary arterial hypertension. J Am Coll Cardiol. 2004; 43(suppl S): 40S–47S. Kitabake A., Inoue M., Asao M., Masuyama T., Joutanouchi M. Noninvasive evaluation of pulmonary hypertension by a Pulsed Doppler technique, Circulation 1983; 68: 302-309. Otto C., Editor, Echocardiographic findings in Acute and chronic pulmonary disease. Text book of clinical Echocardiography, Philadelphia, PA: W.B.Saunders. 2002; 739-757. Yock P. G., Popp R. L. Noninvasive estimation of right ventricular systolic pressure by Doppler ultrasound in patients with tricuspid regurgitation. Circulation. 1984; 70: 657–626.[Medline] McQuillan B. M., Picard M. H., Leavitt M., Weyman A. E. Clinical Correlates and Reference Intervals for Pulmonary Artery Systolic Pressure Among Echocardiographically Normal Subjects; Circulation. 2001; 104: 2797-2802. Fisher M. R., Forfia P. R., Chamera E., Housten-Harris T., Champion HC, Girgis R. E., Corretti M. C., Hassoun P. M. Accuracy of Doppler echocardiography in the hemodynamic assessment of pulmonary hypertension. Am J Resp Crit Care Med 2009; 179: 615-621. Swan H. J., Ganz W., Forrester J., Marcus H., Diamond G., Chonette D. Catheterization of the heart in man with use of a flow-directed, balloon-tipped catheter. N Engl J Med 283: 477, 1970. Christman B. W., McPherson C. D., Newman J. H., King G. A., Bernard G. R. An imbalance between the excretion of thromboxane and prostacycline metabolites in pulmonary hypertension. N Engl J Med. 1992; 327(2):70-5. [Medline] Kidd L., Driscoll D., Gersony W. et al. Second natural history study of congenital heart defects. Results of treatment of patients with ventricular septal defects. Circulation. 1993; 87:138–151. Bousquet J, Dahl R., Khaltaev N. Global Alliance against Chronic Respiratory Diseases. Eur Respir J. 2007; 29: 233–239. Sani M. U., Mukhtar-Yola M., Karaye K M. Spectrum of Congenital Heart Disease in a Tropical Environment: An Echocardiography Study. Niger J Med. 2007; 99(6): 665669 Daliento L., Somerville J., Presbitero P. et al. Eisenmenger syndrome. Factors relating to deterioration and death. Eur Heart J 1998;19: 1845-1855. Gutierrez G., Venbrux A., Ignacio E., Reiner J., Chawla L., Desai A. The concentration of oxygen, lactate and glucose in the central veins, right heart, and pulmonary artery: a


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study in patients with pulmonary hypertension. Critical Care 2007, 11: R44doi:10.1186/cc5739. 17. Hoeper M. M., Lee S. H., Voswinckel R., Palazzini M., Jais X., Marinelli A. et al. Complications of Right Heart Catheterization Procedures in Patients With Pulmonary Hypertension in Experienced Centers J Am Coll Cardiol, 2006; 48: 2546-2552. 18. Arcasoy S. M., Christie J. D., Ferrari V. A., St. John Sutton M., Zisman D. A., Blumenthal N. P., Pochettino A., Kotloff R. M. Echocardiographic Assessment of Pulmonary Hypertension in Patients with Advanced Lung Disease Am J Respir Crit Care Med 2003;167:735-740. 19. Nauser T. D., and Stites S. W. Diagnosis and Treatment of Pulmonary Hypertension Am Fam Physician. 2001; 63(9): 1789-1799.

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20. Bossane E., Citro R., Blasi F., Allegra L. Echocardiography in Pulmonary hypertension: An essential tool. Chest 2007; 131: 339-341. 21. Borges A. C., Knebel F., Eddicks S., Panda A., Schattke S., Witt C., Baumann G. Right ventricular function assessed by two-dimensional strain and tissue Doppler echocardiography in patients with pulmonary arterial hypertension and effect of vasodilator therapy. Am J Cardiol 2006; 98: 530–534. 22. Forfia P. R., Fisher M. R., Mathai S. C., Housten-Harris T, Hemnes A. R., Borlaug B. A., Chamera E., Corretti M. C., Champion H. C., Abraham T. P. et al. Tricuspid annular displacement predicts survival in pulmonary hypertension. Am J Respir Crit Care Med 2006; 174: 1034–1041.


Spinal Anaesthesia for Appendectomy: Experience at the University of Benin Teaching Hospital (UBTH), Benin-city, Edo State, Nigeria

M. O. OSAZUWA , J. M. AFOLAYAN, N. P. EDOMWONYI Department of Anaesthesiology, University of Benin Teaching Hospital, P.M.B. 1111, Benin City, Edo State, Nigeria.

ABSTRACT Background: Appendectomy is the commonest surgical emergency in our hospital. Spinal anaesthesia is one of the anaesthetic techniques for appendectomy; it is simple and safe in experienced hands. We determined the use of spinal anaesthesia for appendectomy and outcome in our centre. Patients and Methods: This was a retrospective study of all cases of appendectomy performed from April 2007 to September 2009 (thirty months), cases that had spinal anaesthesia were further analysed. Information such as patients’ age, gender, ASA physical health status, PCV, urinalysis, anaesthetic technique, surgery duration, supplemental analgesics, intra-operative complications, and outcome, were obtained from anaesthetic and theatre records. Results: Five hundred and thirty-three cases of appendectomy were performed, of which 105 (19.7%) patients received spinal anaesthesia while majority (80.1%) of the cases were done under general anaesthesia and 1 (0.2%) patient had epidural anaesthesia. Eighty-four (80%) of the patients who had spinal anaesthesia had intrathecal administration of a combination of 0.5% hyperbaric bupivacaine and an opioid (25µg Fentanyl or 10mg Pethidine), while 21 (20%) had intrathecal administration of 0.5% hyperbaric bupivacaine without opioid. Of the patients who received spinal anaesthesia, 72 (68.6%) had adequate anaesthesia intra-operatively, 25 (23.8%) patients required supplemental analgesics, while 7.6% cases were converted to general anaesthesia. Complications in the intra-operative period such as hypotension, shivering, high block and itching were managed effectively. Conclusion: The study revealed that use of a combination of 0.5% hyperbaric bupivacaine and an opioid provided effective anaesthesia for appendectomy. We recommend an increasing use of spinal anaesthesia for appendectomy. Keywords: Spinal anaesthesia; Appendectomy; Complications; Outcome INTRODUCTION The incidence of appendicitis in Accra and Lagos is 3 per 10,000 while in England and Wales it is 13 per 10,000.1 Though there is a higher incidence of appendicitis in Europe and America, there is currently a steady increase in the incidence of appendicitis in developing countries with a decrease in western countries.1,2 Acute appendicitis accounts for 30% of surgical emergencies in urban areas of Ghana and Nigeria.1 The incidence of appendicitis in 2008 almost doubled that of 2003 at LAUTECH Teaching Hospital, Osogbo, Nigeria.2 Change to a western lifestyle including change from a high to a low-residue diet has been largely blamed for the rising incidence in the developing countries.3, 4 Appendectomy is a common surgical emergency in the University of Benin Teaching Hospital (UBTH), Benin City, Nigeria. General anaesthesia *Correspondence: Dr. Osazuwa M. O., Department of Anaesthesiology, University of Benin Teaching Hospital, P.M.B. 1111, Benin City, Edo State, Nigeria. E-mail: [email protected]

(GA) has been the most popular anaesthetic technique used for appendectomy. Spinal anaesthesia is a simple and effective anaesthetic technique which also can be used for appendectomy. 5 The advantages of spinal anaesthesia for appendectomy include minimal airway manipulation, reduced risk of aspiration, extension of analgesia into the post-operative period, early ambulation and feeding.6 Spinal anaesthesia is also cheaper than general anaesthesia.5,7 The disadvantages of spinal anaesthesia for appendectomy are pain from peritoneal irritation if the block is not high enough, risk of high spinal, chance of anaesthesia wearing off if surgery is prolonged, hypotension and post-dural puncture headache.7,8 Furthermore, some patients may not tolerate surgery while awake, even when sedated.7 The aim of this study was to determine the use of spinal anaesthesia for appendectomy, complications and outcome. This will help to guide the administration of spinal anaesthesia for appendectomy. PATIENTSAND METHODS This was a retrospective study of cases of


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appendectomy done from April 2007 to September 2009 (period of thirty months). All the cases of appendectomy performed during this period were included in the study. The cases who received spinal anaesthesia were further analysed. Information was derived from anaesthetic paper records and theatre records. Information derived include patients’ age, gender, American Society of Anesthesiologists (ASA) physical health status, packed cell volume (PCV), urinalysis, type of appendicitis, dose of hyperbaric bupicavaine + opioid used, supplemental analgesic such as intravenous ketamine 10-20mg aliquots, IV fentanyl 25µg, IV tramadol 100mg, IV pentazocine 30mg; duration of surgery, intra-operative complications and outcome of management whether it was effective or not. Based on intraoperative events after spinal anaesthesia was established, the patients were categorized into three groups: i) cases that had adequate anaesthesia defined as patients who did not require additional analgesia in the intraoperative period; ii)cases that had supplemental analgesic defined as patients who required additional analgesics to spinal anaesthesia intraoperatively; iii) cases converted to GA defined as patients who had intense pain during surgery that was not relieved by supplemental analgesics. Statistical analysis was carried out using GraphPad Instat version 3. RESULTS Five hundred and thirty three patients had appendectomy from April 2007 to September 2009. One hundred and five (19.7%) patients received spinal anaesthesia, 427(80.1%) were done under general anaesthesia and 1(0.2%) patient had epidural anaesthesia. The age range of patients who had spinal anaesthesia was 14-52years. Seventy four (70.5%) were females while 31(29.5%) were males (p3ml of bupivacaine. (Table 4). Supplemental analgesics given were intravenous ketamine 10-20mg aliquots, IV fentanyl 25µg, IV tramadol 100mg, IV pentazocine 30mg. Complications which resulted from the anaesthetic technique were hypotension (n=2), respiratory difficulty due to high block (n=1), shivering (n=4) and itching (n=2). (Table 5). Occurrence of post-dural puncture headache was difficult to ascertain as only the anaesthetic charts and theatre records were analysed. Hypotension was managed with ephedrine and IV fluids, respiratory difficulty was managed with administration of oxygen by face mask, shivering was treated with warm IV fluids and by covering the patient with blankets. Chlorpheniramine was used to treat itching. Outcome of management of complications was satisfactory. Table 4: Dose of intrathecal bupivacaine versus use of supplemental analgesics/conversion to general anaesthesia 3ml of bupivacaine bupivacaine Number of patients who had adequate anaesthesia (%) 42 (61.8) Number of patients who required supplemental analgesics or conversion to GA (%) 26 (38.2) Total (%) 68 (100)

30 (81.1)

7 (18.9) 37 (100)

Table 5: Complications arising from the use of spinal anaesthesia for appendectomy Complications Hypotension Respiratory difficulty Shivering Itching Total

Number of patients (%) 2 (1.90) 1 (0.95) 4 (3.81) 2 (1.90) 9 (8.56)

DISCUSSION The incidence of spinal anaesthesia for appendectomy in our centre is 197 per 1000 appendectomies. Our study showed an increasing use of spinal anaesthesia for appendectomy, from 110 per 1000 appendectomies in 2007, to 480 per 1000 appendectomies in 2009. This can be attributed to improved skill in the use of spinal anaesthesia by the anaesthetists in our hospital, and to the availability of opioids. The decrease in use of spinal anaesthesia in 2008 was due to irregular supply of opioids during that period. Our results showed that the patients who present for appendectomy are healthy young adults as evidenced by their ages and ASA physical health status. A significant proportion of the patients in our study were female. Mangete et al9 in Port Harcourt, Nigeria, also found a significantly higher incidence of appendicitis in females. Appendicitis though, is generally reported to be more common in males.2 The appendix arises from the posteromedial aspect of the caecum about 2.5cm below the ileocaecal valve; its innervation is derived from sympathetic elements contributed by the superior mesenteric plexus (T10-L1) and afferents from parasympathetic elements via the vagus nerve.10 A spinal block height of T4 is considered adequate for appendectomy in order to prevent pain from manipulation of the peritoneum.7 Spinal anaesthesia is simpler, cheaper and safer than it used to be in the past.11, 12 This may be attributed partly to more standardized doses of local anaesthetics, improved skill and prompt management of complications. It is associated with reduced risk of aspiration, decreased airway manipulation, extension of analgesia into the postoperative period, early ambulation & feeding.6 Opioid receptors have been identified in the substantia gelatinosa of the spinal cord, hence the administration of opioids intrathecally.13 Intrathecal local anaesthetics or opioids are known to block visceral pain.14, 15 A study by Tejwani and colleagues16 has revealed that on intrathecal injection, the antinociceptive effects of morphine, when combined with bupivacaine, were significantly greater than when morphine or bupivacaine was injected alone. They also demonstrated a direct effect of bupivacaine on the binding of opioids to µ and  spinal receptors. Furthermore, a synergistic inhibitory action of local anaesthetics and opioids on A-gamma (I) and C nerve fibres conduction has been demonstrated by Wang et al17; they arrived at the conclusion that “the effectiveness of spinal analgesia with bupivacaine can be enhanced if it is supplemented with fentanyl”. Intrathecal administration of a local anaesthetic or, an opioid + local anaesthetic combination has been shown to provide effective anaesthesia for appendectomy by Techanivate et al.8; in their randomized double-blind study, they assessed the effectiveness of the administration of fentanyl in spinal anesthesia for appendectomy. Forty patients were recruited to receive either 4 ml of 0.5%


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hyperbaric bupivacaine + 20g of fentanyl (Group F) or 4 ml of 0.5 % hyperbaric bupivacaine + 0.4 ml normal saline (Group S). Their study revealed that intrathecal 20 g fentanyl significantly improved the quality of analgesia; it prolonged the duration of bupivacaine in spinal anaesthesia and delayed the analgesic requirement in the early postoperative period. In our study, 72.62% of patients had adequate anaesthesia in the group that received bupivacaine with opioid compared with 52.38% in the group that received bupivacaine alone, thus the percentage of patients who required supplemental analgesics or conversion to GA was less in the group who had intrathecal opioid. Hunt and colleagues15 have also demonstrated that the addition of fentanyl to hyperbaric bupivacaine intrathecally reduces intraoperative opioid supplement as was observed in our study. Seventy two (68.6%) of the total cases in our study had adequate intra-operative analgesia. This is also comparable with Techanivate et al8, in their study, 82.5% of patients had good intraoperative analgesia without supplemental analgesic. Sule and colleagues5 in Jos University Teaching Hospital, Nigeria have as well successfully used spinal anaesthesia for appendectomy, using 0.5% hyperbaric Bupivacaine, in similar doses with our study. Our study revealed a low incidence of side effects of 8.6%. This buttresses the finding by Sudarshan and colleagues18 that intrathecal fentanyl is usually not associated with troublesome side effects, when they investigated the efficacy of intermittent doses of intrathecal fentanyl in 30 patients undergiong thoracotomy. Our study further demonstrated that intrathecal fentanyl or intrathecal pethidine with bupivacaine 0.5% provides excellent surgical anaesthesia with few side effects. This agrees with the findings of Belzarena et al.19 It is recommended that high dose of 0.5% bupivacaine (>3ml) is used when administering spinal anaesthesia for appendectomy, in order to achieve a high enough block.7 Our study revealed a higher occurrence of use of supplemental analgesics or conversion to general anaesthesia in patients who had lower doses of bupivacaine (less than 3ml) compared with those who had >3ml of bupivacaine. Techanivate et al8 reported complications such as nausea & vomiting, hypotension, shivering, high block. In our study, similar complications such as hypotension, shivering, respiratory difficulty and itching occurred and were managed with good outcome. Davies and colleagues20 have also reported respiratory depression following the use of intrathecal opioid. The respiratory difficulty in our study may have been due to high block observed in the patient or the effect of intrathecal opioid. CONCLUSION Our study revealed an increasing use of spinal anaesthesia for appendectomy in our centre. Addition of an opioid to 0.5% hyperbaric bupivacaine intrathecally 14

was more effective than bupivacaine alone for appendectomy. The high incidence of pain that is felt in the intraoperative period from peritoneal irritation during appendectomy can be overcome with the addition of opioid to local anaesthetic intrathecally. We therefore recommend an increasing use of spinal anaesthesia for appendectomy. REFERENCES 1.

2.

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Naaeder S. B. The Appendix. In: Badoe EA, Archampong E. Q., da Rocha-Afodu J. T. editors. Principles and practice of surgery including pathology in the tropics. 3rd edition, Ghana Publishing Corporation. 2000: 519-528 Oguntola A. S., Adeoti M. L., Oyemolade T. A. Appendicitis: Trends in incidence, age, sex, and seasonal variations in South-Western Nigeria. Ann Afr Med 2010; 9 (4): 213-217 Walker A. R., Segal I. Appendicitis: an African perspective. J R Soc Med 1995; 88: 616-619 Burkitt D. P., Walker A. R., Painter N. S. Effect of dietary fibre on stools and transit-times, and its role in the causation of disease. Lancet 1972; 30: 1408-1412. Sule A. Z., Isamade E. S. and Ekwempu C. C. Spinal anaesthesia in lower abdominal and limb surgery: A review of 200 cases, Niger J Surg Res 2005; 7(1-2): 226-230 Amata O. A. Anaesthesia for caesarean section in some tertiary obstetrics units in Nigeria - A pilot study. The Nig Postgraduate Med J. 1998; 5(3): 148-150. Ankcorn C., Casey W. F. Spinal anaesthesia - A practical guide. Update in Anaesthesia 1993; 3: 2-16. Techanivate A., Urusopone P., Kiatgungwanglia P., Kosawinboopol R. Intrathecal fentanyl in spinal anaesthesia for appendectomy. J Med Assoc Thailand 2004; 87(5): 525-530 Mangete E. D., Kombo B. B. Acute appendicitis in PortHacourt, Nigeria. Orient J Med 2004; 16: 1-3. Soybel D. Appendix. In: Norton J. A., Barie P. S., Bollinger R. R., Chang A. E., Lowry S. F., Mulvihill S. J., Pass H. I., Thompson R. W. editors. Surgery: basic science and clinical evidence, 2nd edition, New York. Springer Science + Business Media LLC. 2008: 992-1010 Amata O. A. Incidence of post-spinal headache in Africans. West Afr J Med 1994; 13(1): 53-55 Mgbakor A. C., Adou B. E. Plea for greater use of spinal anaesthesia in developing countries. Trop Doct 2012; 42(1): 49-51 Pertc B., Kuharm J., Snydersh. Opiate receptor: autoradiographic localization in rat brain. Proceedings of the National Academy of Sciences 1976; 73: 3729-3733 Kleinman W., Mikhail M. S. Spinal, epidural, and caudal blocks. In: Morgan G. E., Mikhail M. S., Murray M. J. editors. Clinical Anaesthesiology. 4th Edition, New York. Lange Medical books/McGraw-Hill Medical Publishing Division. 2006: 295-323 Hunt C. O., Naulty A. M., Hauch M. A. Perioperative analgesia with subarachnoid fentanyl-bupivacaine for caesarean delivery. Anesthesiol 1989; 71(4): 535-540 Tejwani G. A., Rattan A. K., McDonald J. S. Role of spinal opioid receptors in the antinociceptive interactions between intrathecal morphine and bupivacaine. Anesth Analg 1992; 74: 726-734. Wang C., Chakrabarti M. K., Whitwam J. G. Specific


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enhancement by fentanyl of the effects of intrathecal bupivacaine on nociceptive efferent but not on sympathetic efferent pathways in dogs. Anesthesiol 1993; 79: 766-773 18. Sudarshan G., Browne B. L., Matthews J. N., Conacher ID. Intrathecal fentanyl for post-thoracotomy pain. Br J Anaesth 1995; 75 (1): 19-22

19. Belzarena SD. Clinical effects of intrathecally administered fentanyl in patients undergoing cesarean section. Anesth Analg 1992; 74: 653-657. 20. Davies G. K., Tolhurst-Cleaver C. L., James T. L. Respiratory depression after intrathecal narcotics. Anaesthesia 1980; 35: 1080-I083.


15

Anaesthesia for Surgical Outreach in a Rural Nigerian Hospital

I. U. ILORI Department of Anaesthesiology, University of Calabar Teaching Hospital

ABSTRACT Background: Surgical outreach to rural areas is aimed at improving access to surgical treatment to a deprived community. The study reports the experience of a team consisting of specialist surgical and anaesthetic manpower during a five day surgical outreach at Ogoja General Hospital, Nigeria in 2010. This was on the occasion of the 50th anniversary of the West African College of Surgeons. Ogoja General Hospital though is a hospital that offers 24 hour surgical services; lacks basic facilities for administration of regional and general anaesthesia for all categories of patients as well as patient monitors. Patients and Method: Patients with surgical pathologies that involved minimum blood loss, postoperative pain and care were selected for surgery having been previously screened by resident medical officers. Results: A total of 119 patients had 136 surgical procedures representing 18.4% of the patients screened. Paediatric patients consisted 46% of the cases done. Majority of the patients were males (73%) and hernia (67%) was the most frequent pathology. The main anaesthetic technique was Spinal Anaesthesia (68.8%) in adults and ketamine based Total Intravenous Anaesthesia (TIVA) (90.9%) in children. There was no mortality and all patients were discharged within 24 hours. Conclusion: Rural dwellers have substantial burden of surgical pathologies that are amenable to surgery but lack access to surgery and safe anaesthesia. Careful selection of patients, specialist manpower and collaborations with the resident healthcare personnel improves outcome. Improvement in anaesthetic facilities and a subsidised health care scheme for the rural dwellers would improve access to safe anaesthesia and surgery. Keywords: Anaesthesia, Challenges, Nigeria, Rural community, Surgical Outreach

INTRODUCTION Surgical outreach in rural areas is to improve access to surgical services to patients who face financial or geographic barriers to surgical care and seeks to attend to as many patients as possible within a limited period.1,2 The West African College of Surgeons (WACS) in commemoration of her 50th anniversary held a surgical outreach in 3 rural communities of Cross River State of Nigeria spread across the 3 senatorial districts, from February 1 to 5, 2010. The communities included Ikot Ene in Akpabuyo, Southern senatorial district, Ugep in Yakurr, Central senatorial district and Ogoja in Ogoja Local Government Area, Northern senatorial district. This article reports the experiences of the team in one of the outreach stations, Ogoja General Hospital, which has 180 provisional bed spaces but actual available beds were 41. There were basic laboratory, radiological as well as blood

*Correspondence: Dr. I. U. Ilori, Department of Anaesthesiology, University of Calabar Teaching Hospital, Calabar 540001. Cross-River State. Nigeria. Email address: [email protected] 16

transfusion facilities but no facilities for administration of safe anaesthesia. A twenty-four hour emergency surgical service coverage is provided by four medical officers and two nurse anaesthetists (one a retired) and anaesthetic assistant said to sometimes administer an anaesthetic. There were three perioperative nurses as well. The Team The team consisted of five surgeons including a paediatric surgeon and two physician anaesthetists. The team was assisted by hospital staff consisting of 2 nurse anaesthetists, 3 perioperative nurses and four auxiliary operating room staff including the anaesthetic assistant. The Anaesthetic Challenges The available anaesthetic machine was a continuous flow TMS type which was a donation but had never been used because of non-availability of medical gases and breathing circuit including face masks. There were no tracheal tubes. There was a suction machine and a manual sphygmomanometer with an adult cuff which had to be shared with the delivery suite. There was no other monitor.


ANAESTHESIA FOR SURGICAL OUTREACH IN A RURAL NIGERIAN HOSPITAL

The operating tables were not tiltable. The two beds in the recovery room were borrowed from the wards. These deficiencies were noted during an earlier visitation to the hospital and a promise was made that it would be rectified. However, on arrival, the observed deficiencies were not rectified. There was difficulty in getting sponsors for the free surgical outreach. However, funding from the Cross River State Government was received just prior to the outreach making it possible to get minimum requirements for regional anaesthesia. Drugs and basic facilities for resuscitation which included a set of laryngoscope, an adult and a paediatric self – inflating resuscitation bags, oropharyngeal airways and some adult endotracheal tubes were also obtained. PATIENTS AND METHOD The resident medical officers screened and selected the patients a week before the arrival of the team. The selected patients were all reassessed preoperatively and investigations included a haemoglobin check in all the patients and urinalysis for adults only. The cases selected were hernias, hydrocoeles, lipomas and subcutaneous cysts. All the patients had a minimum of a six hour pre anaesthetic fast. The anaesthetic techniques used were mainly Spinal Anaesthesia (subarachnoid block), Local Anaesthesia (LA) in adults and Total Intravenous Anaesthesia (TIVA) using ketamine in combination with pentazocine and paracetamol for paediatric patients. Monitoring was mainly through observation of clinical signs and with the aid of manual sphygmomanometer in adults and a precordial stethoscope for paediatric patients. The patients were grouped into paediatric (0 -18 years) and adult (>18years) for analysis. The data was analysed using 2010 Microsoft Excel Worksheet and presented as figures and percentages in tables and charts. RESULTS A total of 645 patients were screened but only 119 (18.4%) had their surgical pathology treated in 136 procedures in five days. There were 32(27%) females and 87(73%) males. Paediatric patients were 55(46%) and adults 64(54%). Figure 1 shows the distribution of surgical pathologies between the two age groups. Hernia was the most common pathology in both age groups. It made up about 67% of the surgeries performed (figure 2). Three were emergencies. These were a caesarean section for an obstructed labour, an appendectomy for ruptured appendix in a 28 year old man and an intestinal resection and anastomosis in a ten year old child with peritonitis secondary to typhoid perforation. The analyses of the anaesthetic techniques used were Spinal Anaesthesia (subarachnoid block) (68.8%), Local Anaesthesia (23.4%) in adults and Total Intravenous Anaesthesia (TIVA) (90.9%) using ketamine (Rotex Medica, Trittau,Germany) in combination with pentazocine (Ranbaxy Laboratories

Limited, Dewas, India) and paracetamol for paediatric patients (Table l). There was no recorded mortality among the patients but there was a case of post-operative nausea and vomiting in a five year old female child. Two of the adult patients who were already screened were discovered to have diabetes mellitus and severe hypertension and surgery was cancelled. They were referred to the Resident Medical Officers for further investigation and possible management or referral to a specialist hospital. Table I:Age Distribution of Anaesthetic Techniques Anaesthetic Technique

Paediatric No (%)

Adult No (%)

Total Intravenous Anaesthesia (TIVA) Local Anaesthesia (LA) Spinal Anaesthesia Spinal Anaesthesia & LA LA & TIVA Total

50(90.9) 3(5.5) 2(3.6) 55

2(3.1) 15(23.4) 44(68.8) 2(3.1) 1(1.6) 64

BIH – Bilateral inguinal hernia; LIH – left inguinal hernia; RIH – right inguinal hernia

Figure 1: Age distribution of surgical pathologies

Figure 2: Percentage distribution of surgical pathologies encountered


17

I. U. ILORI

DISCUSSION About half of the world population live in the rural areas and have greater health needs than urban dwellers yet experience substantial financial difficulties.2 Free surgical outreach especially in rural areas of sub-Saharan African countries is essentially to serve patients with financial and geographical barriers to surgical care. It has the advantages of access to specialist care, treatment near home and shorter waiting time.2,3 The turnouts in such free services are always much more than the team can handle within the short duration of the outreach. In Nigeria, the costs of health services are borne by the patient and their families so free treatment attracts a crowd. In this outreach, more than 645 patients with minor surgical pathologies were screened by the end of the first day. However, only 119 patients (18.4%) were attended to, on whom 136 surgical procedures were carried out. Adigun et al reported a similar percentage (17.6%) of patients screened and treated in a free plastic reconstruction outreach programme in a rural community in another state in Nigeria.4 The most frequent pathology in both adult and paediatric patients was hernia with inguinal hernia being the commonest (Figure 1). Figure 2 shows that hernias consisted 67% of the pathologies treated. A high prevalence of hernia in rural African communities has been reported. In a study by Nordberg in East African countries, the prevalence of hernia was put at 175 per 100,000 and 1400 per 100,000 in Ghana.5.6 The implication is that financial constraints could make people with minor pathology like hernia not to seek medical attention until it becomes obstructed or strangulated. Strangulation is a common complication of hernia associated with substantial morbidity and mortality. When this occurs, it results in great financial loss, which is of grave consequences both to the family and the society. This perceived prevalence of surgical pathologies in rural areas that are amenable to treatment caused the World Health Organisation in 2005 to establish the Global Initiative for Emergency and Essential Surgical Care (GIEESC).7 This initiative is aimed at addressing the deficiencies in surgical care in low and middle income countries. It is therefore, necessary that healthcare policy makers in developing countries evolve a health scheme that is sufficiently subsidised for their disadvantage population. During the five days of the surgical outreach, three emergency surgeries were handled namely caesarean section for an obstructed labour, appendectomy for ruptured appendix and a laparotomy and bowel resection and anastomosis as a result of typhoid perforation. These emergency surgical procedures are common causes of morbidity. Studies in rural Kenyan hospitals and Ethiopia, reported ectopic pregnancy, caesarean section, strangulated hernia, appendectomy and bowel resection as being the common surgical emergencies encountered by medical officers.5,8,9 Obstructed labour was reported in Malawi as being the indication for 63% of the caesarean section.10 Obstructed labour is a predisposing factor for ruptured uterus as well as urogenital fistulae 18

which are major complications of pregnancy and delivery. Typhoid perforation with peritonitis is not an unusual occurrence in this environment and it is a common cause of mortality especially in children.11 The difficulties faced in obtaining specialist care in rural communities can be averted by the training of General Duty Medical Officers in these rural hospitals to handle both minor and common emergency surgical pathologies. A study carried out at district hospitals in Western Cape Province of South Africa underlined the importance of competent medical officers working in rural hospitals being generalist and proficient in primary care as well as surgical skills.12 Infrastructural challenges, such as electricity and running water, lack of job satisfaction due to poorly equipped and nonfunctionality of available equipment as well as poor remuneration have limited recruitment and retention of medical officers and other health personnel in rural hospitals.13 In the Ogoja General Hospital, there was only one manual sphygmomanometer with an adult cuff. The operating tables were not tiltable. There was a continuous flow TMS anaesthetic machine which was a donation but with neither a breathing system nor oxygen. The nearest location where oxygen, in cylinders could be purchased is about a six hour journey one way. Gatrad et al had identified the donation of an anaesthetic machine which requires a supply of compressed gas in an environment there is no gas as a waste of resources.14 Anaesthetic machine donation to rural hospitals in developing countries should be the one that can function with or without compressed gas. The recommended anaesthetic technique in these resource poor environments is regional. It has the advantages of being simple, effective, safe and requiring inexpensive equipment. 15 Spinal anaesthesia (subarachnoid block) and local anaesthesia were the anaesthetic techniques used in adults. A prior visitation to the hospital before the outreach had revealed the nonavailability of facilities for both regional and general anaesthesia. This was what informed the selection of cases to be operated upon being those that could be done under regional anaesthesia. However, there were some unanticipated emergency cases for which general anaesthesia with intubation was the anaesthetic technique of choice because of risk of regurgitation and aspiration. Due to non-availability of appropriate endotracheal tube, ketamine anaesthesia without tracheal intubation was used. An exploratory laparotomy in the ten year old patient with peritonitis, a case of full stomach, was done without tracheal intubation using ketamine as the sole anaesthetic agent. It is necessary in planning for a surgical outreach in a developing environment to make provision for all that is needed for safe anaesthesia for the scheduled cases and also for emergency surgeries. This is because deficiencies noted during a prior visitation to the chosen facility are often not rectified as was observed in this outreach. Though the funding provided by the state government provided basic consumables for both surgery and anaesthesia, it was not possible to purchase any


ANAESTHESIA FOR SURGICAL OUTREACH IN A RURAL NIGERIAN HOSPITAL

tracheal tube with diameter less than 7mm within the Cross River State. An option would have been to refer the patient to the nearest fairly equipped specialist hospital in Calabar, a six hour away. Barrier created by distance, lack of emergency transportation, overnight accommodation, dislocation from family support and high cost have been responsible for over 40% non-attendant to specialist and urban hospitals referrals.3 The other two emergencies, the obstructed labour and ruptured appendix which occurred in adult patients were done using spinal anaesthesia. Though spinal anaesthesia offers a safe, cheap and easy anaesthesia in poor resource hospitals, the hospital had no stock of spinal needles. Hodges et al in a survey of Ugandan hospitals reported lack of basic facilities for the administration of safe anaesthesia in paediatric, adult and obstetric patients in many hospitals especially those funded by government.16 The lack of basic facilities for the administration of anaesthesia in adults, paediatrics and obstetrics was not only at the Ogoja General Hospital but was seen in the other outreach centres which were all government hospitals. This is a deprivation of facilities to enable the provision of safe anaesthesia in government hospitals. Majority of the paediatric patients (90.9%) had their surgery under total intravenous anaesthesia using ketamine. Ketamine based anaesthesia is often perceived to be safe and cheap even in the single handed surgeon. Herniotomy is relatively a short procedure, regional anaesthesia was seen as a waste of time though it could have improved postoperative pain relief. This is because of the pressure to treat as many children as possible in 5 days. It was observed that the children required more than 2mg/kg of ketamine which is the recommended dose for intravenous induction. The duration of action was also short requiring frequent intermittent bolus doses of ketamine. This usually happened when the drug was left at room temperature. The manufacturer recommends 30 degree Celsius as the maximum storage temperature. Often the room temperature exceeds 30 degree Celsius especially during the dry seasons that span between November to March. Therefore to preserve the potency of ketamine in the tropics, it should be stored in a refrigerator or in an air conditioned room. An increased dose requirement of ketamine was also reported during a surgical mission in Sri Lanka.17 All the patients had a single intravenous dose of pentazocine for post-operative analgesia. Majority of the elective cases were discharged in 24 hours on oral analgesics. The pain relief was adjudged adequate as the patients did not complain but were rather appreciative for the free surgical service. There was no recorded mortality. The presence of two physician anaesthetists in the team and a paediatric surgeon accounted for good outcome especially among paediatric patients. This also may have contributed to a large number of children operated on (46%). There was an incidence of postoperative nausea and vomiting (PONV) in one child which was severe enough to delay discharge from the recovery room for

more than three hours. The PONV was treated with a single dose of 12.5mg of promethazine with some relief. The patient was later transferred to the ward and discharged after 24 hours. Complications during a surgical outreach may be inevitable, and when it occurs could be emotionally devastating and politicised. For an improved outcome, the surgical outreach should be in an established medical institution and in cooperation with local medical personnel. This has the advantage of getting an available supporting staff as well as to follow-up the patients in case of any complication. Taking the short duration of surgical outreaches into consideration, it is essential to select cases that do not carry high risk of complication or require protracted period of recovery.1 Re-assessment of the patients despite having been screened by the resident medical officers may also have contributed to minimal morbidity. CONCLUSION This outreach shows that rural dwellers have a substantial burden of minor surgical pathologies but no access to save anaesthesia. The basic facilities for the administration of anaesthesia in general hospitals in the rural areas are non-existent. There is need for Government in the developing countries to equip the general hospital with basic facilities and drugs for safe administration of regional and general anaesthesia as well as monitoring of patients. A healthcare scheme that subsidises or offers free access to the treatment of minor surgical pathologies and common surgical emergencies especially in the low income and rural communities should be evolved. Special welfare or financial incentives policy should be instituted to encourage health personnel to work in rural hospitals. Above all, simple draw-over anaesthetic machine, giant cylinder of oxygen and an oximeter will enable the provision of safe anaesthesia by the nurse anaesthetist in rural subSaharan African hospitals. REFERENCES 1. Wolfberg A. J. Volunteering overseas lessons from surgical

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brigades. New England Journal of Medicine 2006; 354: 443 – 445. Gruen R. L., Bailie R. S., Waqng Z., Head S., O’Rourke I. C. Specialist outreach to isolated and disadvantage communities: a population based study. Lancet 2006; 368: 130 -138 Kifle Y. A., Nigatu T. H. Cost effectiveness analysis of clinical specialist outreach as compared to referral system in Ethiopia: An economic evaluation. Cost Effectiveness and Resource Allocation 2010; 8: 13. Adigun A. I., Adeogba A. O., Sims M. L., Ogundipe K. O. Plastic surgical outreach services in a developing country: The challenges. World Journal of Medical Sciences 2007; 2 (2): 96-100. Nordberg E. M. Incidence and estimated need of caesarean section, inguinal hernia repair and operation for strangulated hernia in rural Africa. British Medical Journal 1984; 289: 92-93.


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Shillcutt S. D., Clarke M. G. Kingsnorth A. N. Costeffectiveness of groin hernia surgery in the Western Region of Ghana. Arch Surg. 2010; 145(10): 954-961 7. GIEESC (2005) WHO meeting towards a Global Initiative for Emergency and Essential Surgical care. www.int/entity/ surgery/mission/GIEESC2005_Report. 8. Nordberg E., Mwobobia I. Muniu E. Major and minor surgery output at district Level in Kenya: Review and issues in need of further research. African Journal of Health Sciences 2002; 9: 17 - 25 9. Ilako F. Assessment of common surgical conditions encountered by medical officers based in rural hospitals in East Africa. AMREF Nairobi, Kenya 10. Fenton P. M., Whitty C. J. M., Reynolds F. Caesarean section in Malawi: prospective study of early maternal and perinatal mortality. British Medical Journal 2003; 327: 587- 590. 11. Ameh E. A., Chirdan L. B. Paediatric surgery in the rural setting: prospects and feasibility. West African Journal of Medicine 2001; 20(1): 52 – 55

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12. De Villiers M. R., De Villiers P. J. T. Theatre and emergency services rendered by General Medical Practitioners in district hospitals in Western Cape. SA Fam Pract 2003; 45(7): 15 – 19. 13. Ozgediz D., Galukande M., Mabweijano J., Kijjambu S., Mijumbi C., et al. The Neglect of the global surgical workforce: experience and evidence from Uganda. World J Surg 2008; DOI 10.1007/s00268-008-9473-4 14. Gatrad A. R., Gatrad S., Gatrad A. Equipment donation to developing countries. Anaesthesia 2007; 62 (Suppl.1): 90 -95. 15. Schnittger T. Regional anaesthesia in developing countries. Anaesthesia 2007; 62(Suppl.1): 44–47. 16. Hodges S. C., Mijumbi C., Okello M., McCormick B. A., Walker I. A. et al. Anaesthesia services in developing countries: Defining the problems. Anaesthesia 2007; 62: 4 –11 17. Anaesthetic experiences in Sri Lanka (January 2001- June 2001) World Anaesthesia News 2002; 6(2): 9 – 11.


Comparison of Caudal Analgesia and Intravenous Diclofenac for Postoperative Pain Relief in Paediatric Patients Undergoing Daycase Herniotomy *

B. K. AROSO , **I. D. MENKITI , ***M. A. AKINTIMOYE , §O. I. O. DADA , §I. DESALU , §O. T. KUSHIMO * Department of Anaesthesia, Federal Medical Centre, Bida, ** Department of Anaesthesia, Lagos University Teaching Hospital, *** Department of Anaesthesia, General Hospital, Gbagada § Department of Anaesthesia, College of Medicine University of Lagos/ Lagos University Teaching Hospital

ABSTRACT Background: Effective postoperative pain management is a vital determinant to when a child can be safely discharged from the hospital after day case surgery. This study compared the effect of caudal bupivacaine block with intravenous diclofenac for postoperative pain relief in children aged 1-7years undergoing herniotomy. Patient and method: Sixty(60) ASA physical status I & II children randomly received caudal block with 0.125% bupivacaine 1ml/kg (Group A) or intravenous infusion of diclofenac 1mg/kg in 4.3% dextrose in 0.18% saline 4ml/kg (Group B) after induction of general anaesthesia. Postoperative pain was assessed in the recovery room with mCHEOPS on arrival, 1, 2, 3, and 4hr intervals. The parents assessed pain for 24 hours postoperatively. Oral paracetamol 20mg/kg was administered if pain was moderate or severe. Total analgesic consumption was compared in both groups at 24hr after surgery. Results: The time to first rescue analgesia was 239.3± 24.6min in group A versus 167.6±43.2min in group B, (p=0.024). Pain scores at 0, 1, 2 and 3hours were significantly different with patients in group A having lower scores at 0-2 hours. The time to micturition was 156.5±28.3min in group A and 182.9±39.5min in group B( p=0.004) while time to ambulation was 186.5± 44.2min in group A, but 218.0± 32.4min in group B (p=0.003).The times to discharge from the recovery room were not different between the groups. Twenty five patients (83.33%) in group A were given oral paracetamol compared with16 patients (53.3%) in group B. No complication was noted in any of the two groups. Conclusion: Caudal bupivacaine provided better post-operativepain relief than i/v diclofenac in the first 3hours after administration but i/v diclofenac decreased pain and analgesic requirement in the latter part of the postoperative period due to its long duration of action. Keywords: caudal analgesia, diclofenac, postoperative pain, children

INTRODUCTION Pain following surgical procedures in children has aroused growing concern in the past few decades. There has been increasing international acknowledgement by the International Association for the Study of Pain (IASP) and World Health Organization (WHO) that pain relief should be a basic human right. The Society of Paediatric Anaesthesia1, at its 15th annual meeting in New Orleans, Louisiana (2001) clearly defined the alleviation of pain as a “basic human right”, irrespective of age, medical condition, treatment or medical institution. Anand’s2 landmark work demonstrated the increase in morbidity and mortality that resulted following inadequate opioid use during and after major surgery in *Correspondence: Dr B. K. Aroso, Department of Anaesthesia Federal Medical Center, Bida. Email – [email protected]

infants. Taddio 3 also showed that un-anaesthetized circumcision of new-borns resulted in increased crying and behavioural response to the pain of immunization needle 4-6 months later. Thus it becomes extremely important to ensure that pain is treated in the paediatric patient to the greatest extent possible. Caudal analgesia is a useful adjunct during general anaesthesia. It provides postoperative analgesia after genital, lower abdominal and lower limb operations. It is usually performed after inhalational or intravenous induction of anaesthesia in children. Benefits include decreased intra-operative requirement for general anaesthetics and less need for the use of parenteral opioids. This limits the incidence of respiratory depression and vomiting which may delay discharge after day case surgery and also reduces the stress response hormones.4 Caudal block has become an integral part of anaesthetic management and has been shown to be satisfactory for


21

COMPARISON OF CAUDAL ANALGESIA AND INTRAVENOUS DICLOFENAC

both intra and postoperative analgesia.5,6,7 Diclofenac is suitable for the management of mild to moderate pain. It has analgesic, anti-inflammatory, antirheumatic and antipyretic activities. Its opioid-sparing effect and availability in parenteral form makes it ideal for day case short stay admissions for elective surgery.8 This study aimed to identify which technique of analgesia would provide better post-operative pain management with minimal side-effects in children aged 1-7 years who had undergone herniotomy as a day case. PATIENTS AND METHODS Institutional ethical committee approval and informed parental consent were obtained. Sixty American Society of Anesthesiology (ASA) classification I-II children aged between 1-7 years under-going elective day case herniotomy were studied. The children were randomly allocated by blind balloting to one of the two groups (Group A or Group B), with 30 patients in each group. Exclusion criteria included known hypersensitivity to amide local anaesthetic or NSAIDS, active or severe renal, hepatic, respiratory or cardiac disease. Patients with a history of seizures, asthma, neuromuscular disorder, clotting disorder, platelet count less than 100,000/mm3 were also excluded. Other exclusion criteria included patients less than 1year old or weighing less than 10kg as well as parental refusal to participate in the study. Routine preoperative fasting 6 hours to solids and 2 hours to clear fluid was strictly adhered to. No premedication was administered. In the operating room precordial stethoscope, electrocardiograph leads, blood pressure cuff and pulse oximeter probe were attached to the patients. Inhalational induction was achieved with gradual increment of halothane up to 3.5% in 100% oxygen via Mapleson F breathing system for patients < 25kg or Bain’s circuit for patients >25kg with appropriate sized face mask. Venous cannulation was performed on the dorsum of the hand when the depth of anaesthesia was adjudged adequate by observing the eyes to be centrally placed, loss of conjuctival reflex, and regular respiration. The airway was maintained with Laryngeal Mask Airway (LMA) of appropriate size (2 or 2.5) Anaesthesia was maintained with O2 in isoflurane 1.5-2.5% with patients breathing spontaneously. Following induction of anaesthesia, Group A received caudal bupivacaine 0.125% (1ml/kg), using a 23guage cannula under aseptic condition with the patient in the lateral position while Group B received 1mg/kg diclofenac diluted in 4.3% dextrose in 0.18% saline 4ml/kg infused over 10minutes. Surgery was allowed to proceed immediately after completion of the administration of the drugs under investigation. Data collected included age, gender, weight, surgical procedure and ASA physical status, duration of surgery, duration of anaesthesia, time to recovery, time to micturition, time to ambulation, time to first analgesia and postoperative pain scores. 22

Study period started immediately after transfer of patients to the recovery room. During this time, a nurse blinded to the two groups assessed the pain using mCHEOPS at 0 (arrival in recovery room), 1, 2, 3 and 4 hours and assigned a numerical value to five behavioural patterns - cry, facial expression, verbalization, torso and leg movements (Appendix I). A score of 6 as moderate to severe pain and i.v paracetamol 15mg/kg was given as the rescue analgesia at this point. Further pain assessment was discontinued on all patients that received rescue analgesia. Parents were instructed on how to assess pain as none, mild, moderate or severe; and rated pain at home for 24 hours after discharge. Oral paracetamol was given at home to any child whose pain was rated as moderate to severe (>6) in ages 4- 7yrs and those between age 1 and 3yr that refused food and could not be consoled following crying. Total analgesic consumption at home was documented. Data collected was analyzed with the Statistical Package for Social Sciences (SPSS® 13 Inc. Chicago Illinois). Data obtained were subjected to statistical analysis using Student-t test, Chi-square and Fischer’s test. All parametric data were reported as mean ± standard deviation and all categorical data as frequencies. A p value of < 0.05 was accepted as statistically significant. RESULTS The demographic data showed no significant difference between the two groups. Both groups showed male dominance of similar magnitude (Table 1). Though the mean duration of surgery was longer in the caudal group, this was not statistically significant (p=0.08). The duration of anaesthesia was longer in the caudal compared with the diclofenac group (p 6 and were removed from subsequent pain assessment as they received rescue analgesia (Fig.1). At 1hour, the mean pain score was still 0 for the caudal group but 3.9± 2.32 in the diclofenac group (p< 0.0001). Figure 2 shows that all the patients that received caudal block still had no pain. Six patients (25%) experienced moderate to severe pain in the diclofenac group and received rescue analgesia. At 2hours, the mean pain scores were still significant between the 2 groups (p6 in the caudal group (Fig. 4). At 4 hours the patients in the caudal group experienced more pain (p6. In the late postoperative period, 25 patients (83.33%) in the caudal group had oral paracetamol at home compared with 16 patients (53.3%) in the diclofenac group (p= 0.026). No complication was observed in any of the two groups. Table II: Comparison of Duration of Recovery, First Analgesia, Micturition, Ambulation and Discharge Mean ± SD

Group A (n = 30)

Group B (n = 30)

P value

Group BRecovery Analgesia Micturition Ambulation Discharge

56.7 ± 17.5 239.0 ± 24.6 156.5 ± 28.3 186.5 ± 44.2 270.7 ± 14.2

42.6 ± 3.2 167.6 (43.2 SEM) 182.9 ± 39.5 218.0 ± 32.4 264.0 ± 11.0

0.0001 0.0239 0.004 0.003 0.05

P < 0.0001 Figure 1: Distribution of Pain Score at 0 hour

Figure 2: Distribution of Pain Score at 1 hour

P = 0.0006 Figure 3: Distribution of Pain Score at 2 hours

Table III: Mean Post-operative Pain Scores at 0, 1, 2, 3 and 4 hours Time (hr)

Group A

Group B

P value

0

0.0 ± 0.0 (n = 30) 0.0 ± 0.0 (n = 30) 0.9 ± 1.8 (n = 30) 4.2 ± 1.7 (n = 30) 5.7 ± 1.1 (n = 29)

2.7 ± 2.7 (n = 30) 3.9 ± 2.3 (n= 24) 3.7 ± 2.2 (n = 18) 2.6 ± 2.0 (n = 12) 1.6 ± 2.1 (n = 12)