Intraperitoneal injection via a paravertebral approach in rabbits

Objective To explore a simple and reliable method for intraperitoneal injection through a paravertebral approach in rabbits. Methods Sixty New Zealand rabbits were randomized into conventional group and modified groups to receive intraperitoneal injections through conventional and paravertebral approaches, respectively. In the conventional group, the injection site was on the abdominal wall 3~4 cm lateral from the umbilicus bilaterally, while that in the modified group was located dorsally at L5/L6 level 3-4 cm lateral from the midline. Abdominal CT scan was performed in the post-injection rabbits, which were sacrificed after 24 h for abdominal dissection. Results Success with a single puncture was achieved in 13 out of the 20 rabbits in the conventional group, and the rest required at least two punctures, with a mean rank sum of 23.50. With the modified approach, a single attempt was successful in all the 40 rabbits, with a mean rank sum of 34.0, showing a significant difference between the two groups(P0.01). The success rates of a single injection differed significantly between the two groups(P0.01). CT scan and abdominal dissection showed that the injection site with the modified approach was far away from the vital organs and large vessels with less peritoneal hyperemia and exudation. Conclusion Paravertebral intraperitoneal paracentesis is a convenient and reliable method for intraperitoneal injection in rabbits.