supine pcnl 2025 versus prone pcnl .pptx

supine pcnl 2025 versus prone percutaneous nephrolithotomy

1. Supine PCNl Prof.Dr . Ahmed Sebaey Benha university

2. INTRODUCTION: Percutaneous nephrolithotomy (PCNL) is the treatment of choice for renal stones >2 centimetres . traditional prone position for PCNL is favoured by a majority of urologists familiarity with the procedure, larger surface area for choice of puncture site potentially more direct approach to the kidney

3. History The classic prone position was initially described in 1976 . In 1987-88, Valdivia- Uria et al, reported a safe percutaneous access to the kidney with the patient supine and 10 years later they reported the in vivo experience.

4. Supine positioning: May be purely supine with legs separated and flexed. A 3-L water or air bag is situated under the lumbar fossa of the target kidney

5. The edge of the bag and the patient's flank are alongside the surgical table edge, in order to facilitate the free movement of the nephroscope. The patient's legs may be extended (with their feet oriented upwards or slightly obliquely) or flexed on leg supports

6. Puncture: It is easy to explore the kidney with dye and fluroscopy or an ultrasound 3.5-mhz probe The skin entry point must be situated one or two Fingers above the 3-L bag & is always behind the post axillary line. Puncture is done in an ascending direction Selected calyx is well distended with contrast, and then renal capsule is palpated with the tip of the needle.

7. Advantages of supine PCNL: Surgeon works comfortably Surgeons hand are not in X ray field No need to change the position of the patient

8. Advantages of supine PCNL: o Less anasthesia risk o Intervention is better tolerated in high risk patients o Good in obese patients , as skin to stone distance is less

9. In certain cases low-regional anesthesia with IV sedation is tried ,if required conversion is easier Risk of puncturing the colon is less ,as the 3-L bag elevates the lumbar fossa, the kidney and the colon are elevated too.

10. Ability to perform simultaneously PCNL and URS. With the two endoscopes inside the kidney it is easier to find fragment, remove and deliver the stone fragments to be extracted through the Amplatz sheath

11. Ascending nature of the tract , maintains low intra renal pressure , no need of auxiliary instruments to extract the stone fragments. The upper calyx was successfully approached in 20% of prone and 80% of supine percutaneous nephrolithotomies.

12. Disadvantages of supine PCNL: There is usually a delay in the filling of the inferior calyces with the contrast, because the inferior renal pole is more elevated than the superior one can be overcome by keeping the patient in anti tendelenburg position for some minutes. Distention of the collecting system will be greater in the prone than in the supine position

13. In some thin patients with renal ptosis, the kidney can be hypermobile in the supine position overcome by fixing the kidney during tract establishment by means of contralateral abdominal compression)

14. Patients with wide hips and thin calyces, it can be more difficult in the supine position to reach the upper calyx with a rigid nephroscope. (can be solved by performing simultaneously a URS, or by using a flexible nephroscope) In the supine position upper pole is more medial and posterior, making access more difficult when required.

15. According Falahatkar et al , De S M et al, the transfusion rate for PCNL performed in the supine position was 8.8% versus 4.3% when performed prone (182 and 207)patients, respectively; P = . 07). In a review, de la Rosette et al. examined the effect of patient positioning. concluding that for obese patients or those with staghorn calculi, the prone position was associated with similar bleeding rates, but decreased operative times, and slightly improved stone-free rates compared to the supine position

16. Conclusion: This technique is a faster way to perform PCNL with the same outcomes.

17. Thank you