External suction versus simple water-seal on chest drainage following pulmonary surgery: an updated meta-analysis.

OBJECTIVES

The decision to apply simple water-seal drainage or the addition of an external suction to the simple water-seal drainage following pulmonary surgery is made based on the surgeon's experience or preference and has remained controversial. This meta-analysis aimed to assess the effects of the addition of suction to simple water-seal on the postoperative outcomes.

METHODS

PubMed, EMBASE and Web of Science were searched from their inception to 30 August 2017. The risk ratio and the weight mean difference were calculated for dichotomous and continuous outcomes, respectively, each with 95% confidence intervals (CIs). The heterogeneity and risk of bias were also assessed.

RESULTS

A total of 10 randomized controlled trials enrolling 1601 patients were included. Overall, compared with simple water-seal, the addition of external suction reduced the occurrence of postoperative pneumothorax (risk ratio 0.35, 95% CI 0.13-0.93; P = 0.04) and other cardiopulmonary complications (risk ratio 0.65, 95% CI 0.48-0.89; P = 0.008), and increased the duration of chest tube drainage (weight mean difference 0.92 days, 95% CI 0.04-1.81, P = 0.04). However, the effect difference between the 2 groups was not significant regarding air leak duration, length of hospital stay and the occurrence of prolonged air leak. The stability of these studies was strong. No evidence of publication bias was detected.

CONCLUSIONS

The addition of suction to simple water-seal made no difference to air leak duration, hospital stay or the occurrence of prolonged air leak following pulmonary surgery. In patients where there is concern about a residual or increasing pneumothorax, the addition of suction may be applied selectively.