Experimental development of an intra-abdominal chemohyperthermia model using a closed abdomen technique and a PRS-1.0 Combat CO2 recirculation system.

Abstract

Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy is the best operative treatment currently available for patients with peritoneal carcinomatosis of ovarian origin. The open abdomen technique is the classic technique for hyperthermic intraperitoneal chemotherapy. We developed a closed abdomen model that improves temperature control and increases exposure of peritoneal surfaces to the drug by recirculating the perfusate. We used a porcine model with 12 female, Large White pigs-4 in the open technique group and 8 in the closed technique CO2 group. We performed cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for 60 minutes using paclitaxel (175 mg/m(2)) at an input temperature of 42°C. Perfusate recirculation was performed under controlled pressure (range, 12-15 mmHg). The infusion of 0.7 L of CO2 via a separate intraperitoneal infusion catheter mixed the perfusate within the peritoneal cavity. Intra-abdominal temperature was assessed using 6 intra-abdominal temperature probes and 2 temperature probes in the inflow and outflow circuits. Drug distribution was assessed using methylene blue staining. Intra-abdominal temperatures remained constant and homogeneous in all intra-abdominal quadrants with a constant input temperature of 42°C and a minimum output temperature of 41.4°C. The infused CO2 caused the fluid to bubble and created agitation inside the abdominal cavity to facilitate a homogeneous distribution of the drug-containing perfusate. The closed recirculation hyperthermia with intraperitoneal chemotherapy technique developed in this study is safe and feasible, and may provide a more homogeneous delivery of heated chemotherapy to the peritoneal cavity in patients with peritoneal malignancies.