Comparison of Stone Free Rate of Supine Vs Prone Position in Percuteneous Nephrolithotomy

Background: Percutaneous nephrolithotomy is a minimally invasive surgical modality for the management of most renal stones. It is effective and safe for majority of the stones large than 2cm, including staghorn stones and stones in previously operated kidneys. PCNL is usually performed in the prone position. Supine position is an alternative to prone with equal stone clearance besides other potential advantages comparing with the prone position. Objective: To compare the stone free rate of supine vs prone position in percutaneous nephrolithotomy (PCNL) Material and Methods: This Randomized controlled study was conducted at Institute of kidney diseases, Hayatabad Medical st st Complex, Peshawar from 1 January 2014 till 31 December 2017. Total 220 patients 150 males and 70 females with renal stones from 20mm to 30mm were included in the study through a technique of non-probability sampling. Patients with staghorn stones, coexisting renal and skeletal anomalies were excluded. These patients were divided into group A (supine PCNL) or group B (prone st th PCNL). They underwent PCNL and stone clearance were assessed and compared for both supine and prone PCNL on 1 and 30 postoperative day. Chi square test was applied for comparison of stone free. P-value = 0.05 was considered significant. st th Results: Stone clearance was analyzed for the two groups at 1 postoperative day and at 30 postoperative day by applying chi st square test. On 1 postoperative day stone clearance was significantly greater in supine position (P=0.002) than prone PCNL. In prone position PCNL, there was complete stone clearance in 70(63.63%) patients while 40(36.36%) patients had residual stones. th Similarly, in supine PCNL, 90(81.81%) patients had complete stone clearance while 20(18.18%) had residual stones. On 30 postoperative day, stone clearance was not statistically significant (P=0.288) between supine PCNL and prone PCNL. In prone position PCNL, there was complete stone clearance in 91(82.72%) patients while 19(17.27%) patients had residual stones. Similarly, in supine PCNL, 95(86.36%) patients had complete stone clearance while 15(13.63%) had residual stones. Conclusion: This study showed that supine PCNL has comparable stone free rate to that of prone PCNL. Current data support the feasibility of PCNL in supine position and this technique can be considered as a promising alternative in treating patients with uncomplicated stones and those with high anesthesiologic risk.