Effects of needle gauge and syringe size on small intestinal leakage at injection sites

Abstract

To determine the influence of needle gauge, syringe volume, and syringe size on needle tract leakage after injection in porcine jejunum. Ex vivo experiment. Three hundred sixty jejunal segments from 20 feedlot pigs. Fresh porcine intestines were divided into 5-cm or 10-cm segments and randomly assigned to the one of nine treatment groups: 25-gauge, 22-gauge, and 20-gauge needles attached to full 12-mL, half-full 20-mL, and full 20-mL syringes (n = 20/group). The jejunal segments were occluded with Rochester-Carmalt forceps prior to injection of diluted India ink. Injection time and leakage were noted by a blinded observer. Multivariate analysis was used with segment size, needle gauge, volume infused, time to inject per milliliter, and syringe size as variables. Leakage occurred in 36% of 5-cm and 15% of 10-cm segments and was immediate without palpation in 33.8% and 11% of segments, respectively. Protective effects were seen for 22-gauge needles in both 5-cm (P = .002) and 10-cm (P = .001) segments, whereas injection of 20 mL had a higher odds ratio of leakage compared with injection of 10 mL and 12 mL in 5-cm segments (P = .003). Injections with 22-gauge needles reduced the frequency of leakage, while 20 mL instilled in 5-cm segments increased the frequency of leakage in intact segments of porcine jejunum. Injection with a smaller syringe size attached to a 22-gauge needle through a 10-cm segment of small intestine may lower the frequency of leakage from the injection site, but influence on the detection of surgical site leakage remains unknown.