BEST EVIDENCE TOPIC
Interactive CardioVascular and Thoracic Surgery 14 (2012) 834–838 doi:10.1093/icvts/ivs037 Advance Access publication 5 March 2012
Is routine chest radiography indicated following chest drain removal after cardiothoracic surgery? Amir H. Sepehripour*, Shakil Farid and Rajesh Shah Department of Cardiothoracic Surgery, Wythenshawe Hospital, Manchester, UK * Corresponding author. Department of Cardiothoracic Surgery, Wythenshawe Hospital, Southmoor Road, Manchester M23 9LT, UK. Tel: +44-07834697517; e-mail:
[email protected] (A.H. Sepehripour). Received 16 November 2011; received in revised form 17 January 2012; accepted 20 January 2012
Abstract A best evidence topic was written according to a structured protocol. The question addressed was whether routine chest radiography is indicated following chest drain removal in patients undergoing cardiothoracic surgery. A total of 356 papers were found using the reported searches; of which, 6 represented the best evidence to answer the clinical question. The authors, date, journal, study type, population, main outcome measures and results are tabulated. Reported measures were mean duration of drains left in situ, timing of drain removal, pathology detected on chest radiographs (CXRs), interventions following imaging and clinical assessment, complications in patients not undergoing routine CXRs and the cost saving of omitting routine CXRs. One large cohort study reported the detection of pathology in 79% of clinically indicated CXRs in comparison to 40% of routine CXRs (P = 0.005). Ninety-five per cent of the nonroutine CXR cohort remained asymptomatic and required no intervention. One large observational study reported the detection of new pneumothoraces in 9.3% of patients, 70.3% of which were barely perceptible. Intervention following CXR was required in 0.25% and only one medium-sized pneumothorax would have been potentially missed without CXR. Another large observational study reported intervention following CXR in 1.9% and the presence of relevant clinical signs and symptoms to be a significant predictor of major intervention (P < 0.01). A smaller observational study reported no pathology detected or intervention following CXR in 98% and the cost saving of omitting a single CXR at £10 000 per annum. Another small observational study reported only 7% of CXRs to be clinically indicated with a false-positive rate of 100%, and a false-negative rate of 7% in CXRs not clinically indicated. The smallest study reported no complications in the non-CXR cohort and only one patient undergoing intervention in the routine CXR cohort. We conclude that there is evidence that routine post drain removal CXR provides no diagnostic or therapeutic advantage over clinically indicated CXR or simple clinical assessment. The best evidence studies reported the detection of pathology on routine CXR ranging from 2 to 40% compared with 79% in clinically indicated CXRs (P = 0.005). Whilst the rate of intervention following routine CXR was as high as 4% in the smallest study, clinical signs and symptoms suggestive of pathology were a significant predictor of major re-intervention (P < 0.01). Keywords: Chest drain • Chest radiography
INTRODUCTION A best evidence topic was constructed according to a structured protocol. This protocol is fully described in ICVTS [1].
CLINICAL SCENARIO A 67-year old man has undergone combined coronary artery bypass grafts and aortic valve replacement. He is haemodynamically stable and requiring no support, has good gas exchange and his post-operative chest radiograph is satisfactory. He has three chest drains in situ with no drain output for the last 4 h. You decide to remove the drains and contemplate whether he
will require an immediate chest radiograph if clinical examination reveals no abnormality.
THREE-PART QUESTION In [patients undergoing cardiothoracic surgery] is [routine chest radiography] indicated following [chest drain removal]?
SEARCH STRATEGY MedLine from 1948 to November 2011 using the PubMed interface ‘radiography’ OR (‘radiography’ [MeSH Terms]) AND (‘chest
© The Author 2012. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
A.H. Sepehripour et al. / Interactive CardioVascular and Thoracic Surgery
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Table 1: Best evidence papers Patient group
Outcomes
Key results
Comments
McCormick et al. (2002), Ann Thorac Surg, USA [2]
1021 consecutive patients undergoing cardiac surgery by median sternotomy
Mean duration of drain left in situ
1.4 days (1–7)
Retrospective cohort study (level 3 evidence)
Exclusion criteria were death in the cardiovascular recovery unit or death with chest drains in situ (n = 21)
Chest drain retained after post-operative Day 1
292 patients [high output (266), air leak (15), pneumothorax (7), critical condition (3), pleural effusion (1)]
Omission of routine postoperative chest drain removal CXRs in postoperative cardiac patients is safe. The removal of chest drains in these patients is not an indication for CXRs
Routine CXR Group Findings
Normal—419 (60%) Effusion—251 (36%) Pneumothorax—22 (3%) Effusion + pneumothorax—11 (2%)
Requiring intervention (drain or thoracocentesis)
14 patients (2%)
Non-routine CXR group
14 patients (5%) had clinically indicated CXRs: No pathology—3 (1%) Effusion—6 (2%) Pneumothorax—4 (1.3%) Effusion + pneumothorax—1 (0.3%)
Requiring intervention (drain)
2 patients (0.6%)
No routine CXR, asymptomatic and no intervention required
283 patients (95%)
Adverse events following omission of routine CXR
Zero
Follow-up in non-CXR group
231 patients (82%) Mean 11 days post-discharge 32 (14%) had CXR at follow-up None required re-intervention
CXRs revealing pathology
11 of 14 (79%) of clinically indicated CXR, 281 of 703 (40%) of routine CXR, (P = 0.005)
400 consecutive patients undergoing cardiac surgery
Mean duration of drain left in situ
1.8 days (1–6)
All patients had routine post drain removal CXR
Total number of pneumothoraces detected on CXR
51 patients (12.8%)
Number of pre-existing pneumothoraces
14 patients (3.5%)
Number of new pneumothoraces
37 patients (9.3%) 70.3%—tiny (barely perceptible) 27%—small (
