RESUMO
BACKGROUND: Abdominal drains have been placed prophylactically and removed in liver resection without robust evidence. The present study was designed to establish the optimal time for removal of such drains. METHODS: Data on abdominal prophylactic drains were analysed in a consecutive series of patients who underwent liver resection for malignancy between 2006 and 2009. Bilirubin levels in drain fluid were measured and bacteriological cultures were taken on days 1, 3, 5 and 7 after surgery. Drains were removed on day 3 if the drain-fluid bilirubin level was less than 5 mg/dl and bacteriological cultures were negative. Drains remained in situ until these conditions were met. RESULTS: A total of 514 abdominal drains were placed in 316 patients operated on in the study period. Fifty-eight patients (18·4 per cent) had positive drain-fluid cultures and 14 (4·4 per cent) had bile leakage (drain-fluid bilirubin level 5 mg/dl or more). Only one patient required ultrasound-guided abdominal drainage. On multivariable analysis, drain-fluid bilirubin level on day 3 after surgery was the strongest predictor of infection (odds ratio 15·11, 95 per cent confidence interval 3·04 to 92·11; P < 0·001). The area under the receiver operating characteristic curve on day 3 had the highest predictive value: 83·6 per cent accuracy and 3·9 per cent false-positive rate for a drain-fluid bilirubin level of 3·01 mg/dl (51·5 µmol/l). CONCLUSION: The '3 × 3 rule' (drain-fluid bilirubin level below 3 mg/dl on day 3 after operation) is an accurate criterion for removal of prophylactically placed abdominal drains in liver resection.
