Do subcutaneous sutures increase risk of laparotomy wound suppuration?

REASONS FOR PERFORMING STUDY Incisional drainage and suppuration occurs commonly following exploratory laparotomy; any technique with the potential to reduce the incidence of this complication warrants investigation. OBJECTIVES To determine if abandoning the use of subcutaneous sutures in laparotomy wound closure is safe and whether it reduces the risk of suppuration. METHODS A randomised controlled study was carried out at 2 referral hospitals in the UK, involving 309 horses undergoing exploratory laparotomy; 150 horses underwent '2-layer' closure without a subcutaneous suture, while 159 underwent conventional '3-layer' closure. Information regarding degree of oedema and gross types of discharge was recorded daily; suppuration was defined as discharge of pus. Telephone follow-up was carried out 30 days after hospital discharge to identify those complications occurring after that date and, thereafter, every 3 months. The influence of closure method on risk of wound suppuration was assessed by Chi-squared analysis and by logistic regression. Time to suppuration was modelled using a Cox proportional hazards model. RESULTS No catastrophic failures of 2-layer closures were recorded. Prevalence of suppuration was not significantly different, being 18.7% and 23.9% for 2- and 3-layer closures, respectively (OR = 1.37, 0.79-2.37, P = 0.263). CONCLUSIONS AND POTENTIAL RELEVANCE This study found no significant difference in prevalence or rate of wound suppuration in 2-layer closures compared to conventional 3-layer closure. Two-layer closure is recommended as a safe alternative means of achieving ventral midline abdominal closure in horses.