Complete supine versus semi supine position in percutaneous nephrolithotomy


Siavash Falahatkar M.D , Ali Ghasemi M.D. , Keivan Gholamjani Moghaddam M.D. , Samaneh Esmaeili M.S. , Ehsan Kazemnezhad Ph.D., Seyed Naser Seyed Esmaeili M.D., Reza Motiee M.D. Urology Research Center, School of Medicine, Guilan University of Medical Sciences


Siavash Falahatkar -

Purpose: To compare the complexity of surgery, access tostone and outcomes of percutaneous nephrolithotomy in the supine versus semi supine position in a prospective randomized trial in order to select the position of the fittest and best.

Materials & Methods: Between July 2011 and May 2014, a total of 44 patients who presented for PCNL were prospectively enrolled and randomly divided into 2 groups (complete supine group (n=22), and semi supine group (n=22). The results in both positions were compared regarding the complexity of surgery, access tostone and outcomes.

Results: The two groups were comparable in age, gender, BMI, and preoperative GFR, Hb and creatinin. The mean operative time was significantly shorter for complete supine vs semi supine (36.68±14.12 min vs 47.50±16.45 min, P=0.024). At the angle of 0˚, overlapping with the spineoccurred in 7 patients (31.8%) in semi supine group and just in 1 patient (4.5%) in complete supine group and also, overlapping with the edge of bed occurred in 10 cases (45.5%) of complete supine and 1 (4.5%) of semi supine, that the differences were statistically significant (P=0.023, P=0.002, respectively). There was no significant difference between two groups for overlapping at the angle of 30˚ with the spine and the edge of bed. No significant difference was found between the two groups in terms of stone free rate and complications.

Conclusion: Although, during the last minutes of the semi supine procedure we had to convert two cases into complete supine but in this study we have shown PCNL in both complete and semi supine position is safe, effective and suitable for the patients. The stone free rate was similar in both groups. But the complete supine position is associated with a significantly shorter postoperative hospital stay and operative time, which may improve ease and safety of PCNL for patients.