Higher flow rates improve heating during hyperthermic intraperitoneal chemoperfusion.

Abstract

Heated intraperitoneal chemotherapy (HIPEC) kills cancer cells via thermal injury and improved chemotherapeutic cytotoxicity. We hypothesize that higher HIPEC flow rates improve peritoneal heating and HIPEC efficacy. (1) A HIPEC-model (30.8 L cooler with attached extracorporeal pump) was filled with 37°C water containing a suspended 1 L saline bag (SB) wrapped in a cooling sleeve, creating a constant heat sink. (2) HIPECs were performed in a swine model. Inflow, outflow, and peritoneal temperatures were monitored as flow rates varied. (3) Flow rates and temperatures during 20 HIPECs were reviewed. Higher flow rates decreased time required to increase water bath (WB) and SB temperature to 43°C. With a constant heat sink, the minimum flow rate required to reach 43°C in the WB was 1.75 L/min. Higher flow rates lead to greater temperature gradients between the WB and SB. In the swine model, the minimum flow rate required to reach 43°C outflow was 2.5-3.0 L/min. Higher flows led to more rapid heating of the peritoneum and greater peritoneal/outflow temperature gradients. Increased flow during clinical HIPEC suggested improved peritoneal heating with lower average visceral temperatures. There is a minimum flow rate required to reach goal temperature during HIPEC. Flow rate is an important variable in achieving and maintaining goal temperatures during HIPEC.