Comparison of Post–Operative Hydrothorax in Supra 12th Rib  Versus Infra 12th   Rib Access in Prone  Mini Percutaneous Nephrolithotomy

Objective: To determine the risk of post-operative hydrothorax in supra-12th rib versus infra-12th rib access in prone Mini Percutaneous Nephrolithotomy. Study Design: Quasi-experimental study. Place and Duration of Study: Armed Forces Institutes of Urology, Rawalpindi Pakistan from Jun to Dec 2022. Methodology: In our study, 110 patients underwent assessment for indication of Percutaneous Nephrolithotomy, level of access, anatomy, site of puncture, incidence of hydrothorax, and requirement of closed-tube thoracostomy. Results: Of the 110 patients who underwent prone Percutaneous Nephrolithotomy, 55(50%) patients underwent infra 12th rib tract approach (Group-1), and the rest, 55(50%) underwent supra 12th rib tract approach (Group-2) depending upon the location of stones, anatomy of pelvicalyceal system and stone burden. Overall, 10(9.09%) patients developed post- Percutaneous Nephrolithotomy Hydrothorax; out of these ten patients, 8(14.5%) patients were approached from the supra 12th rib tract and the remaining 2(3.6%) patients were approached from the infra 12th rib tract (p-value=0.047). Conclusion: The study concludes that in prone Percutaneous Nephrolithotomy, infra-12th rib tract renal access is safer than supra-12th rib renal access regarding chest complications (Hydrothorax).