Repeat Large-Volume Paracentesis Versus Tunneled Peritoneal Catheter Placement for Malignant Ascites: A Cost-Minimization Study

The objective of this study was to determine the point in time at which tunneled peritoneal catheter placement becomes less costly than repeat large-volume paracentesis (LVP) for patients with malignant ascites. Procedure costs were based on 2013 Medicare reimbursement rates. Rates for specific complications were obtained from the literature and were assigned costs. A decision tree-based Markov chain Monte Carlo model was designed with 11 cycles of 10 days, to simulate 4000 subjects per trial. Patients were grouped according to initial treatment decision (LVP vs catheter placement), and the total cost at the end of each 10-day cycle was calculated. The point at which catheter placement became less costly than LVP was determined. Additional simulations were used for bivariate analyses of all cost and probability variables and for trivariate analysis of cycle length and volume of fluid drained per cycle. Individual input probabilities were not significantly different from corresponding simulation outcomes (p value range, 0.068-0.95). When complications were included in the model, the cost curves crossed at a mean (± SD) of 82.8 ± 3.6 days (range, 75.8-89.6 days), corresponding to a time between the performance of the ninth and 10th LVP procedures. Intersection occurred earlier in simulations with a shorter cycle length and less fluid per cycle, but it was minimally affected by changing individual complication probabilities and costs. For patients with malignant ascites, LVP becomes more costly once the procedure is performed nine or 10 times or at approximately 83 days, if paracentesis is repeated every 10 days, with 5 L of fluid removed each time. Use of a tunneled peritoneal catheter improves the cost advantage for patients who receive LVP more frequently or patients who have less than 5 L of fluid drained per procedure.