Table 2.

Characteristics of Hernia Repair Studies Examining the Relationship between Drains and Surgical Site Infection

Authors	Year	Study Type	Procedure	Drain type	Drained n (%)	Undrained (%)	Duration of drainage	Perioperative antibiotic administration	SSI Outcome	Cultures	Comments
Kaafarani et al.	2010	Retrospective analysis of RCT	Laparoscopic vs. open hernia repair with mesh	–	41 (28.3; open repairs only)	104 (71.1)	Removed when output <25 mL/d	100%	Presence of a drain: 79.0% (SSI) vs. 49.3% (no SSI), p=0.21	–	Duration of drainage: 5.0±1.8 d (SSI) vs. 4.6±3.0 d (no SSI), p=0.627
Simchen et al.	1990	Cohort	Hernia repair	Open (60%) and CS (40%)	292 (19.6)	1195 (80.4)	–	–	Drain: RR 4.1, p=0.001; 15.7% (open) vs. 10.1% (CS), p=0.115	–	Overall SSI rate: 4.6%

CS=closed-suction; RCT=randomized controlled trial; RR=relative risk; SSI=surgical site infection.