Diameter and Pressure of the Water-Jet For Liver Resection

Abstract

Objective: The aim of this study was to evaluate theeffect of various nozzle diameter and different liquiddelivery pressure on efficacy of water-jet in experimen-tal liver resection.Method: Depending on the used nozzle diameter, theanimals were divided into two groups. In the first groupof animals, the nozzle diameter was 0.1 mm and thisgroup was divided into 3 subgroups depending on theliquid pressure applied: 8 ATM, 12 ATM and 16 ATM,with 5 water-jet liver dissection is in each subgroup.Water-jet dissection with nozzle diameter of 0.2 mmwas used in the second group of animals, which wasdivided into three subgroups with 5 water-jet liver dis-section in each, depending on liquid pressure: 4 ATM,8 ATM and 12 ATM. The criteria such as blood loss,operation time, parenchymal necrosis, expired liquidvolume, and postoperative complications were usedfor comparison.Results: Water-jet with a diameter of 0.1mm and pres-sure of 12 ATM showed faster cutting with reasonableblood loss when compared to the low pressure sub-group (8 ATM) and result in lesser parenchymal necro-sis, smaller expired liquid volume and acceptablespeed of resection when compared to the high pres-sure subgroup (16 ATM). Increase of the pressure from4 to 12 ATM of water-jet with diameter of 0.2 mm re-sulted in increase of blood loss and necrosis, but didnot effect the speed of resection significantly. Despitelesser blood loss and smaller necrosis, the water-jetat 4 ATM had slower speed of resection. Water-jet withdiameter of 0.2 mm and pressure of 8 ATM cut livermore faster without significantly effecting blood lossand necrosis in comparison to that at a pressure of 4ATM.Conclusion: Our study showed that, increasing thenozzle diameter and liquid delivery pressure resultedin an increase of blood loss and tissue necrosis. Wa-ter-jets with diameter of 0.1 mm and pressure of 12ATM is more acceptable for resection of normal liv-ers.Key words: Liver resection, water-jet