Calcutta position: A new modified supine decubitus for supine PCNL

INTRODUCTION

PCNL (percutaneous nephrolithotripsy) is considered the gold standard treatment for renal stone more than 2 cm. In today's scenario, supine PCNL is considered equally effective as prone PCNL. The ideal position for supine PCNL is still debatable. We hereby describe our initial experiences of supine PCNL in a novel position.

METHODS AND MATERIALS

This prospective study includes 60 patients who underwent supine PCNL in the 'Calcutta position' in our institute from August 2021 to August 2022. Successful procedure was defined as a complete stone free rate or a clinically insignificant residual stone (<4 mm).

RESULTS

Average Operative room (OR) occupancy time was 130.9 ± 19.63 min. The immediate stone free rate was 84.2%, 71.4% and 37.5% for single, multiple and staghorn calculus respectively. Complications include fever, requirement of blood transfusions and renal colic. The average hospital stay was 83.6 ± 17.42 h. Eight patients (13.3%) required secondary procedures like extracorporeal shock wave lithotripsy (ESWL) or relook PCNL. At 3 months average stone free rates were 92%, 85%, 75% for single, multiple and staghorn calculus respectively. We performed supine PCNL in Calcutta position in obese, kyphoscoliosis, poliomyelitis, autosomal polycystic kidney disease (ADPKD), malrotated kidney and diverticular stone with comparable success.

CONCLUSION

Supine PCNL in Calcutta position is a safe and effective option for nephrolithiasis management. Apart from the inherent advantages of supine PCNL it also has the advantages of better C-Arm and nephroscope manoeuvrability. Supine PCNL in Calcutta position was performed in a variety of scenarios with comparable results.

Prone versus supine percutaneous nephrolithotomy: a systematic review and meta-analysis of current literature

INTRODUCTION

Percutaneous nephrolithotomy (PNL) can be performed either in prone or supine position. This study aimed at gathering together randomized controlled trials (RCTs) comparing efficacy and safety between prone and supine PNL.

EVIDENCE ACQUISITION

Systematic review of literature was conducted using the Scopus, Medline and Web of Science databases. Study selection, data extraction and quality assessment were independently assessed by two authors. Meta-analysis was performed with Review Manager 5.3. Sensitivity analyses were performed to exclude studies with high risk of bias.

EVIDENCE SYNTHESIS

Pooled data from 12 studies including 1290 patients were available for analysis. Only one study was found to have overall low risk of bias. Significantly shorter operative time was found in favor of supine PNL (mean difference 13 minutes, 95% confidence interval [CI]: 3.4-22.7; P<0.01). Stone-free rate (SFR)≥14 days after surgery was significantly higher in prone PNL (odds ratio [OR]=2.15, 95% CI: 1.07-4.34; P=0.03). Significantly higher fever rate was found in prone PNL (OR=1.60, 95% CI: 1.03-2.47; P=0.04). Overall SFR, hospital stay length, complications rate, transfusions rate and blood loss, as well as non-lower calyx puncture rate, puncture attempts and tubeless intervention rate did not differ between prone and supine PNL (P>0.05).

CONCLUSIONS

Efficacy of PNL seems balanced between prone and supine position, with comparable overall SFR and shorter operative time in favor of supine PNL. Safety of PNL appears in favor of supine PNL, with lower fever rate. Because of study heterogeneity and possible risks of outcome bias, results from this study should be interpreted with caution. Altogether, both prone and supine PNL account for appropriate therapy options.

Position: prone or supine is the issue of percutaneous nephrolithotomy

INTRODUCTION

The prone position has been considered the only position for percutaneous access to the kidney for the past 25 years, whereas the supine Valdivia position has recently started to gain acceptance, although it was originally described in the late 1980s. Even more recently, the Galdakao-modified supine Valdivia position was described. However, there is no consensus on which is the best position for percutaneous nephrolithotomy, and the choice is currently based on the surgeon's preference.

MATERIALS AND METHODS

The prone, supine, and modified supine positions are described, pointing out the advantages, disadvantages, and results of each technique.

RESULTS

A number of potential advantages have been described for the supine over the prone position: less cardiovascular change; no need for patient repositioning (with less associated risk of central and peripheral nervous system injury); less X-ray exposure to the surgeon; and less risk of colonic injury. The recently described Galdakao-modified supine Valdivia position allows for a simultaneous anterograde and retrograde approach to the renal cavities for the one-stage treatment of complex renal stones or concurrent renal and ureteral calculi. Moreover, the use of a flexible ureteroscope allows for Endovision puncture to achieve perfect access to the kidney.

CONCLUSIONS

The prone position still represents the standard for percutaneous access to the kidney, and other positions should be compared with this position. However, the supine and the modified supine positions have potentially important advantages for both patients and surgeons that need to be investigated in a large randomised trial to define their superiority over the traditional prone position.