A Randomized Comparative Study of CUSA and Waterjet in Liver Resections

Liver resection is considered challenging because of the complex anatomy and abundant vascularity of the liver. Blood loss is an important determinant of outcome, and the risk of bleeding is highest during parenchymal transection. Various techniques and devices have been devised to improve accuracy and speed of parenchymal transection, while minimizing blood loss and collateral tissue damage. There has been a wide adoption of tissue-selective parenchymal transection devices for liver resection with growth of living donor liver transplantation. However, there is inconsistent and conflicting evidence regarding superiority of one device over the other. We compared two most commonly used tissue-selective parenchymal transection devices, Cavitron Ultrasonic Surgical Aspirator (CUSA) and Waterjet for differences in efficacy and adverse effects. A single-center prospective, randomized comparative trial was performed. Patients undergoing elective liver resections in the hepatobiliary and liver transplant unit of a tertiary referral hospital over 2 years were randomized to either the CUSA or Waterjet groups. Blood loss before, during, and after liver parenchymal transection were recorded. Postoperative adverse events, serial bilirubin, prothrombin time (PT) levels, and liver enzymes were monitored until discharge. Fifty patients were randomized equally between the CUSA and Waterjet groups. Parenchymal transection times for the Waterjet and CUSA were 181 SD12 min and 174 SD 7.8 min, respectively (p-value 0.6). Mean blood loss in the Waterjet and CUSA were 496.2 SD 48.66 mL and 471.5 SD 43.61 mL, respectively (p-value = 0.59). Peak aspartate transaminase (AST) levels in the Waterjet and CUSA were 386.32 SD 45.80 U/L and 389.84 SD 63.54 U/L, respectively. ALT levels in the Waterjet and CUSA were 348.76 SD 44.32 U/L and 339.24 SD 40.97 U/L (p = 0.87). Peak bilirubin levels in the Waterjet and CUSA groups were 3.076 SD 0.48 and 3.10 SD 0.39 mg/dL, respectively (p = 0.969). Peak prothrombin time in the postoperative period in the Waterjet and CUSA were 17.36 SD 0.40 and 18.24 SD 0.98 s, respectively (p = 0.414). The CUSA and Waterjet were similar in terms of time taken for liver parenchymal transection and blood loss. There was no significant difference in morbidity, mortality, or markers of hepatocyte injury with either technique. In the absence of a clear difference, availability and surgeon preference is likely to determine the choice of device for liver resections.