Background: Percutaneous nephrolithotomy (PCNL) is traditionally performed under general anesthesia, with the patient in the prone position. However, various concerns have been raised regarding the prone position, especially in morbidly obese patients with compromised cardiopulmonary status and comorbidity issues. Our aim was to demonstrate our experience with supine miniaturized PCNL performed under spinal anesthesia in a high-risk patient.

Case Report: A 76-year-old Thai woman with obesity and severe hyperglycemia presented with two large right kidney stones. She was scheduled for prone PCNL. During admission, she was in a severe hyperglycemic state, with a blood glucose level of 537 mg/dL. She required an intravenous insulin infusion and was monitored until stable. Because she had significant potential risk for general anesthesia, we decided to remove the stone by supine miniaturized PCNL under spinal anesthesia. She was placed in the Galdakaomodified supine Valdivia position. Cystoscopy was performed and a ureteric catheter was inserted into right ureteric orifice. The lower pole access was carefully punctured under ultrasonographic guidance. The tract was dilated with a metallic one-step dilator and a 12 Fr nephroscope was used. Lithotripsy was undertaken using a holmium laser through a 550 micron laser fiber. The procedure was completed with no deterioration of the patient.

Conclusion: A patient with kidney stones, obesity, and poor glycemic control has an increased risk of perioperative complications. We report the first case of supine miniaturized PCNL performed under spinal anesthesia in Thailand. It is a safe and feasible method that provides satisfactory positive clinical outcomes.

Keywords: Supine; Miniaturized percutaneous nephrolithotomy; Regional anesthesia