Safe use of intraoperative intraperitoneal crystalloid fluid administration in management of late-term pregnant queens undergoing elective ovariohysterectomy.

Objective: Evaluate the safety and effectiveness of intraoperative IP crystalloid fluid administration for the prevention of hypotension and perfusion deficits, as well as the impact of intra-abdominal pressure (IAP), following removal of the gravid uterus in late-term pregnant queens undergoing elective ovariohysterectomy.

Methods: This was a prospective, randomized, case-control study. Pregnant queens presenting to a high-volume spay-and-neuter clinic for elective ovariohysterectomy between March 2021 and May 2023 were included and randomly assigned into intraoperative IP versus postoperative SC fluid control groups. The volume of IP fluids administered was equivalent to 25% of the gravid uterus weight, while the volume of SC fluid was 22 mL/kg. Perfusion parameters and IAP measurements were collected preoperatively, during abdominal closure, and 10 minutes after surgery.

Results: No difference was detected between pre- and postoperative perfusion parameters in the 50 pregnant queens (blood pressure, lactate, and IAP) between the IP and control groups. However, increased uterus weight was associated with a higher blood pressure and IAP preoperatively. No adverse effects found within the IP fluids group.

Conclusions: No adverse effects or significant differences were found between IP fluid administration and control groups in 50 late-term pregnant queens. However, IP fluid administration may still be a viable option for fluid administration in shelter settings. Further veterinary studies are warranted.

Clinical relevance: Traditional fluid administration via the IV route is not always feasible in high-volume shelter settings. Studies evaluating the use of the IP fluid route and effects on perfusion parameters are important to determine its effectiveness in veterinary patients.