surgical anesthesia to T8 and complete motor block of ... general anesthesia the block was complete. The ... tomography, contrast myelography and cisternogra-.
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recognition by the brain of injurious stimuli conveyed by afferent impulses. Usually benign, nausea is a complex neurophysiologic response to nociperception. Teleologically, from the evolutionary perspective, it is a protective mechanism to assure the survival of the organism through the elimination of the noxious stimulus or agent. The brain is so complex in its circuitry, receptors and neurotransmitters, that it is not possible for the clinician to pinpoint the area of the brain that has been subjected to disequilibrium. This may not be possible even with the aid of an electroencephalogram in a way that is tantamount to a standardized physical, chemical or electrical stimulation of a well-defined anatomic or functional arena such as chemoreceptor trigger zone (CTZ) or emetic centre (EC) in an experimental animal. The emetogenic potential of CTZ and EC is well known. However, it is not known how nociception impacts the neurologic infrastructure including pathways, receptors, neurotransmitters and thresholds. Integration of this hypothesis into practice by this author has been found to be safe and effective in preventing the unintended clinical consequence of PONV. Elective surgical patients do not normally suffer from preoperative nausea and vomiting; nor do they show any predisposing factors such as hypotension, fever, bacteremia, septicemia and toxemia of pregnancy. Routine administration of pharmacologic agents, such as droperidol, metoclopramide, and ondansetron, is neither cost effective nor justified. This author believes that the primary focus ought to be on the prevention of nociception that helps reduce the overall incidence of PONV. The professional community is invited to evaluate the hypothesis and report their experiences. The best days are yet to come for this method of prevention. S. Rao Mallampati MD FACA Boston, Massachusetts
Possible asymptomatic cerebrospinal fluid leak following successful labour epidural catheter placement To the Editor: We report the case of a parturient with a possible asymptomatic, cutaneous cerebrospinal fluid (CSF) leak 35 hr postepidural catheter placement, without a known dural puncture. The patient is a 21-yr-old, 61 kg G2P1, female, who accepted epidural analgesia for the management of labour pain. The epidural space
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was identified by loss of resistance to saline with an 18-gauge Hustead epidural needle. A non-styletted catheter was advanced 4 to 6 cm into the epidural space without resistance. Aspiration and a test dose were negative. The patient received a bolus of 0.2% ropivacaine (7 mL) with sufentanil 10 µg. A continuous epidural infusion of 0.1% ropivacaine with sufentanil 1 µg·mL–1 was started at 7 mL·hr–1 and pain relief was achieved for the next eight hours. One hour later, we were called for a Cesarean section for arrest of labour. The patient was given 0.5% bupivacaine with epinephrine 1:200000, incrementally to 20 mL. At incision, the patient complained of sharp pain in her left side, at which point general anesthesia was induced uneventfully. The emergence and recovery room stay were uneventful. On awakening, she had surgical anesthesia to T8 and complete motor block of the lower extremities. Our anesthesia service removed the epidural catheter intact 21 hr postinsertion. We were called again 14 hr postcatheter removal because of fluid leakage at the dressing site. The patient was sitting and fluid was freely dripping from the epidural insertion site without any other symptoms. The clear fluid was collected. The nitrazide test showed a pH result of 7.0 to 7.5, glucose was 146 mg·dL–1. Laboratory analysis revealed total protein 588 mg·dL–1, specific gravity 1.009, and glucose 103 mg·dL–1. With these results, the fluid leak was assumed to be CSF. Later that day, the sterile dressing was wet and a second dressing was applied, which remained dry and intact until discharge. Magnetic resonance imaging (MRI) showed a normal unenhanced lumbar spine, with no epidural or sc fluid collection. The patient was discharged four days postoperatively without complications. Identifying the specific cause of this possible CSF leak is problematic. The epidural catheter placement was uneventful and infusion resulted in good pain relief for ten hours without any signs of subarachnoid block or local anesthetic toxicity. On emergence from general anesthesia the block was complete. The patient did not ever show any symptomatology from this possible CSF leak. Testing for glucose is helpful in identifying CSF,1 although it could be present in both inflammatory and non-inflammatory exudates.2 If this was truly CSF, the increased protein level could be attributed to meningeal vasodilatation and subsequent diapedesis of proteins.3 Definitive tests include immunofixation electrophoresis for beta-2-transferrin4 and beta-2transferrin found only in CSF and perilymph.5 Radiographic studies are helpful, including computed tomography, contrast myelography and cisternogra-
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phy. MRI is very sensitive in detecting CSF accumulation and pseudomeningocele. Sabry Ayad MD Samer Narouze MD John E. Tetzlaff MD Cleveland, Ohio References 1 Lauer KK, Haddox JD. Epidural blood patch as treatment for a surgical durocutaneous fistula. J Clin Anesth 1992; 4: 45–7. 2 Eismont FJ, Wiesel FW, Rothman RH. Treatment of dural tears associated with spinal surgery. J Bone Joint Surg Am 1981; 63: 1132–6. 3 Pannullo SC, Reich JB, Krol G, Deck MD, Posner JB. MRI changes in intracranial hypotension. Neurology 1993; 43: 919–26. 4 Bosacco SJ, Gardner MJ, Guille JT. Evaluation and treatment of dural tears in lumbar spine surgery: a review. Clin Orthop 2001; 389: 238–47. 5 Skedros DG, Cass SP, Hirsch BE, Kelly RH. Beta-2transferrin assay in clinical management of cerebrospinal fluid and perilymphatic fluid leaks. J Otolaryngol 1993; 22: 341–4.
Maxillary jewelry in a parturient: a new cause for concern To the Editor: A new fashion of self-expression through body piercing in unconventional sites among young adults (including pregnant women) appears to continue to
FIGURE Gingival jewelry (anterior view).
increase in our society. We previously described the anesthetic implications of oral (tongue piercing),1 and nasal (alar piercing),2 jewelry in parturients requiring anesthesia in the peripartum period, and made a recommendation that oral/nasal jewelry should be removed prior to the administration of anesthesia (of any kind). However, we recently administered an uneventful epidural anesthesia to a 22-yr-old parturient with a non-reassuring fetal heart tracing for forceps assisted vaginal delivery. The patient had a piece of jewelry attached to her maxillary gumline with through and through fixation (Figure). Removal of the maxillary jewelry would have required special tools. We elected to not try and remove the maxillary jewelry because of the urgent nature of the case. We would welcome comments from colleagues from other institutions on their guidelines for the management of labour analgesia in parturients presenting with oral/nasal jewelry in situ. Krzysztof M. Kuczkowski Penna K. Bui MD San Diego, California
MD
References 1 Kuczkowski KM, Benumof JL. Tongue piercing and obstetric anesthesia: is there cause for concern? J Clin Anesth 2002; 14: 447–8. 2 Kuczkowski KM, Benumof JL, Moeller-Bertram T, Kotzur A. An initially unnoticed piece of nasal jewelry in a parturient: implications for intraoperative airway management. J Clin Anesth 2003; 15: 359–62.
Remifentanil pretreatment for propofol injection pain in children To the Editor: Pain on propofol injection is a recognized problem in the pediatric population and several methods have been studied to reduce its incidence and severity.1,2 We designed this study to assess the effectiveness of remifentanil in minimizing pain on injection of propofol in children. After Ethics Committee approval and written parental informed consent, healthy children ASA I or II status aged 5 to 12 yr scheduled for otolaryngological surgery were included in the study. Children with a past history of an adverse response to propofol, who refused iv induction, in whom we failed to insert an iv cannula on the back of the hand or who had cognitive or behavioural disorders were excluded from the study. When the patient arrived in the anes-
