A bacteriologic study comparing closed suction and simple conduit drainage.

A simple experimental study was designed to determine if closed suction drainage reduces the migration of pathogenic bacteria along a drain tract. Sixty New Zealand rabbits, equally divided into three groups, were splenectomized through midline incisions. Group I served as the control group and received no drainage. Groups II and III had drainage of the splenic bed with simple latex conduit drains (Penrose drains) and closed suction drains (Jackson-Pratt drains), respectively. The skin near the drain exit site was inoculated with a Streptococcus organism. The animals were sacrificed after 72 hours, and intraperitoneal culture specimens were obtained. None of the control rabbits had positive cultures on intraperitoneal specimens. Eighteen of 20 rabbits (90 percent) in Group II (Penrose) had positive cultures on specimens from the splenic bed, whereas 75 percent had positive cultures on drain specimens. Only 4 of 20 (20 percent) of the Group III rabbits had positive cultures on the drain or splenic bed specimens. This difference was statistically significant by chi-square analysis (p less than 0.001). Retrograde migration of bacteria along a drain tract does occur with relatively high frequency with simple conduit drainage and is significantly less with closed suction drainage.