A Comparative Study Between Holmium Laser, Pneumatic Lithotripsy and Shock Pulse in Terms of Efficacy and Safety in Percutaneous Nephrolithotomy (PCNL): A Prospective Randomized Study

Abstract

Background and ObjectivesPercutaneous nephrolithotomy (PCNL) occupies an essential place in the treatment of upper urinary tract calculi. PCNL also accomplishes higher stone-free rates and requires fewer auxiliary procedures than shock wave lithotripsy (SWL) and ureterorenoscopy (URS) for renal stones between 1–2 cm. There are different intracorporeal lithotripter devices available. This study aims to compare the efficacy and safety of holmium laser, pneumatic lithotripsy and Shock Pulse in PCNL.
 Materials and MethodsA prospective randomized study was performed in Gauhati Medical College & Hospital, Guwahati, Assam, India, between October 2016 to November 2018. Patients of renal calculi and upper ureteric calculi less than or equal to 2.5cms and functioning kidney on the ipsilateral side were included. 300 patients were randomized according to a random number generator. In the holmium laser, pneumatic and Shock Pulse groups’ number of patients was 96, 102, 102 respectively. Stone disintegration time (SDT), stone-free rate, failure rate, success rate, irrigant used, mean hematocrit drop were evaluated. Statistical analysis was done to compare and predict any significant difference.
 ResultsPatients were divided into groups depending on the lithotripter used: group A (n=96), group B (n=102), group C (n=102) were holmium laser, pneumatic lithotripsy, and Shock Pulse respectively. No significant difference in stone location (p=0.785),Hounsfield unit (p=0.115),complication rates between the groups. Stone free rate in laser, pneumatic lithotripter, and Shock Pulse were 81.25%, 67.65%, 82.35% (highest in Shock Pulse and lowest in the Pneumatic group) and failure rate were 6.25%, 14.7%, 5.89% respectively. A significant difference was found in terms of stone-free, success rate, clinically insignificant residual fragments(CIRF)and failure rates between the groups(p<0.001). Irrigant requirement (litre/mm3) between the groups is statistically significant (p<0.001) with the highest in Shock Pulse and lowest in the Pneumatic group. Mean hematocrit drop: 4.19%, 4.20%, 5.46% in Laser, Pneumatic and Shock Pulse respectively. No significant difference between Laser and Pneumatic group (p=0.907), but in Shock Pulse group it is significantly higher. (p< 0.001)
 ConclusionEfficacy of energy sources used in PCNL for stone fragmentation vary in terms of stone clearance, failure rates, SDT, irrigant requirement and mean hematocrit drop. In our study, we found stone clearance signifi-cantly higher in Shock Pulse than Pneumatic and Laser groups. Stone fragmentation volume per unit time highest in Shock Pulse and lowest in Laser. Irrigant requirement highest in Shock Pulse group and compa-rable between Laser and Pneumatic group. The higher irrigant requirement in the Shock Pulse group may be the cause for higher hematocrit drop in this group. Complications between the groups are comparable.