Wound drains after incisional hernia repair

Incisional hernias are caused by the failure of the wall of the abdomen to close after abdominal surgery, leaving a hole through which the viscera protrude. Incisional hernias are repaired by further surgery. Surgical drains are frequently inserted during hernia repair with the aim of facilitating fluid drainage and preventing complications. Traditional teaching has recommended the use of drains after incisional hernia repair other than for laparoscopic ventral hernia repair. More than 50% of open mesh repairs of ventral hernias have drains inserted. However, there is uncertainty as to whether drains are associated with benefits or harms to the patient. To determine the effects on wound infection and other outcomes, of inserting a wound drain during surgery to repair incisional hernias, and, if possible, to determine the comparative effects of different types of wound drain after incisional hernia repair. We searched the Cochrane Wounds Group Specialised Register (last searched March 2006), the Cochrane Central Register of Controlled Trials (CENTRAL)(The Cochrane Library Issue 1, 2006), EMBASE (1974 to March 2006), PubMed (1951 to March 2006), and Science Citation Index Expanded (1974 to March 2006). We also searched the meta-register of controlled trials. We considered all randomised trials performed in adult patients who underwent incisional hernia repair and that compared using a drain with no drain. We also considered trials that compared different types of drain. We extracted data on the characteristics of the trial, methodological quality of the trials, outcomes (e.g. infection and other wound complications) from each trial. For each outcome we calculated the risk ratio (RR) with 95% confidence intervals (CI) and based on intention-to-treat analysis. Only one trial was eligible for inclusion in the review with a total of 24 patients randomised to an electrified drain (12 patients) compared with a corrugated drain (12 patients). There were no statistically significant differences between the groups for any of the outcomes (a variety of measures of infection). There is insufficient evidence to determine whether wound drains after incisional hernia repair are associated with better or worse outcomes than no drains.