A national analysis of in-hospital outcomes following cytoreductive surgery with HIPEC.

e16497 Background: Cytoreductive surgery with hyperthermic intra-peritoneal chemotherapy (HIPEC) is an aggressive multi-modal treatment strategy used in carefully selected patients with peritoneal surface malignancies. The procedure combines extensive surgical debulking with intra-peritoneal circulation of heated chemotherapy to eradicate residual microscopic disease while limiting systemic toxicity. In this study, we examined in-hospital outcomes, healthcare resource utilization, and palliative and end-of-life care patterns associated with HIPEC using a nationally representative inpatient database. Methods: We conducted a retrospective cohort study using the National Inpatient Sample to identify adult hospitalizations for colorectal, ovarian, appendiceal, gastric, primary peritoneal, and secondary peritoneal malignancies. Hospitalizations involving HIPEC were compared with non-HIPEC cancer related admissions. Survey weighted multivariable logistic and linear regression models were used and adjusted for patient demographics, hospital characteristics, and Elixhauser comorbidities. The primary outcome was in-hospital mortality. Secondary outcomes included ICU admission, mechanical ventilation, central venous catheterization, vasopressor use, blood transfusion, length of stay, total hospital charges, palliative care consultation, and do not resuscitate (DNR) status. Results: Among approximately 3 million abdominal cancer related hospitalizations, 6,950 patients underwent HIPEC, most commonly for colorectal, ovarian, appendiceal, and peritoneal malignancies. After multivariable adjustment, HIPEC was associated with significantly lower in-hospital mortality (adjusted odds ratio [aOR] 0.11; 95% CI 0.05–0.24; p < 0.001). HIPEC was associated with higher utilization of critical care resources, including ICU admission (aOR 1.68), mechanical ventilation (aOR 1.77), central venous catheter placement (aOR 1.49), vasopressor support (aOR 2.67), and blood transfusion (aOR 1.44) (all p≤0.01). HIPEC was also associated with longer hospital stay (+2.60 days) and higher total charges (+$127,467) (both p < 0.001). Notably, HIPEC recipients were significantly less likely to receive palliative care consultation (aOR 0.11) or DNR orders (aOR 0.03) (both p < 0.001). Conclusions: In this large national cohort, HIPEC was associated with lower in-hospital mortality regardless of substantially increased critical care utilization, length of stay, and costs, suggesting a favorable short term survival benefit despite utilization of high intensity care. The low utilization of palliative and end-of-life care may reflect the highly selected nature of the population undergoing this procedure and a predominant intent of HIPEC as life prolonging therapy.