Evaluation of factors predicting clinical pleural injury during percutaneous nephrolithotomy: a prospective study

The purpose of this study is to prospectively identify factors that predict the chance of pleural injury (detected clinically or on postoperative X-ray chest) during percutaneous nephrolithotomy (PCNL). All patients with renal/upper ureteric stones, undergoing PCNL between January 2013 and June 2014, were evaluated for pleural injury. An erect chest X-ray on inspiration was done within 6 h of PCNL. The patients were divided into Groups A and B depending on whether they developed or did not develop pleural injury. Patient-, stone-, renal-, and procedure-related factors were compared between the two groups. 332 patients with mean age 36.76 ± 15.01 years (range 4-80) and M:F of 172:160 fulfilled the inclusion criteria. Pleural complications occurred in 10 patients (3 %). Of 141 patients with supracostal punctures (59 had additional infracostal punctures), 4.2 % (n = 6) had pleural injury. Of 191 patients with only infracostal punctures, 4 developed pleural injuries (2 %). Patients in group A had significantly lower age (27.00 ± 11.18 vs. 37.06 ± 15.03, p = 0.03) and lower BMI (18.0 ± 1.90 vs. 21.12 ± 2.24 p = 0.002). Incidence of pleural injury was significantly higher (p = 0.001) on right side [4.0 % (7/172) vs. 1.8 %, 3/160)]. Incidence of pleural injury had no association with staghorn calculi, stone surface area (590.51 ± 313.88 for Group A vs. 593.02 ± 387.10 for Group B; p = 0.11), degree of hydronephrosis, and operative time (65.13 ± 19.45 for Group A vs. 72.21 ± 19.56 for Group B; p = 0.06). On multivariate analysis, only low BMI and mean age <27 years were associated with higher risk of pleural injury. Higher incidence of pleural injury was noted in patients with low BMI and younger age.