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

Objective: To determine the influence of needle gauge, syringe volume, and syringe size on needle tract leakage after injection in porcine jejunum.

Study Design: Ex vivo experiment.

Sample Population: Three hundred sixty jejunal segments from 20 feedlot pigs.

Methods: 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.

Results: 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).

Conclusion: 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.

Clinical Significance: 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.