Development of a novel automatic ascites filtration and concentration equipment with multi‐ring‐type roller pump units for cell‐free and concentrated ascites reinfusion therapy

Cell‐free and concentrated ascites reinfusion therapy (CART) is an effective therapy for refractory ascites. However, CART is difficult to perform as ascites filtration and concentration is a complicated procedure. Moreover, the procedure requires the constant assistance of a clinical engineer or/and the use of an expensive equipment for the multi‐purpose blood processing. Therefore, we developed a CART specialized equipment (mobility CART [M‐CART]) that could be used safely with various safety measures and automatic functions such as automatic washing of clogged filtration filter and self‐regulation of the concentration ratio. Downsizing, lightning of the weight, and automatic processing in M‐CART required the use of newly developed multi‐ring‐type roller pump units. This equipment was approved under Japanese regulations in 2018. In performing 41 sessions of CART (for malignant ascites, 22 sessions; and hepatic ascites, 19 sessions) using this equipment in 17 patients, no serious adverse event occurred. An average of 4494 g of ascites was collected and the total amount of ascites was processed in all the sessions without any trouble. The mean weight of the processed ascites was 560 g and the mean concentration ratio was 8.0. The ascites were processed at a flow rate of 50 mL/min. The mean ascites processing time was 112.5 minutes and a 106.5‐minutes (95.2%) ascites processing was performed automatically. The operator responded to alarms or support information 3.2 times on average (3.1 minutes, 2.1% of ascites processing time). Human errors related to ascites processing were detected by M‐CART at 0.4 times per session on average and were appropriately addressed by the operator. The frequencies of automatic washing of clogged filtration filter and self‐regulation of the concentration ratio were 31.7% and 53.7%, respectively. The mean recovery rates (recovery dose) of protein, albumin, and immunoglobulin G were 72.9%, 72.9%, and 71.2% (65.9 g, 34.9 g, and 13.2 g), respectively. Steroids were administered in 92.7% of the sessions to prevent fever and the mean increase in body temperature was 0.53°C. M‐CART is a compact and lightweight automatic CART specialized equipment that can safely and easily process a large quantity of ascites without the constant assistance of an operator.