Flexible ureteroscopic lithotripsy: first-line therapy for proximal ureteral and renal calculi in the morbidly obese and superobese patient.

Abstract

The surgical treatment of kidney and proximal ureteral stones in morbidly obese patients (>14 kg/m2) remains difficult because shockwave lithotripsy is precluded by weight limitations and percutaneous nephrolithotomy is associated with difficult access and a high (9%) rate of transfusion. We review our experience with retrograde ureteroscopic lithotripsy in morbidly obese patients with renal and proximal ureteral stones. Between December 1992 and April 2000, five women and three men with a mean age of 46.5 years (range 33-68 years) and a mean body mass index of 54 (range 45-65.2) underwent 10 independent ureteroscopic procedures for urolithiasis. The average stone size was 11.1 mm (range 5-25 mm). Lithotripsy was performed with the holmium laser in eight patients (60%) the electrohydraulic lithotripter in four (30%), and the tunable-dye laser in the remaining patient. Stone-free status was defined as no stones visible on a plain film with nephrotomograms or CT scan at 3 months. The mean operation time was 101 minutes (range 45-160 minutes), and 60% of the procedures were done on an outpatient basis. After the initial procedure, the stone-free rate was 70%. Two patients had fragments <4 mm, and no further therapy was undertaken. There was one complication: transient renal insufficiency (serum creatinine concentration 3.7 mg/dL) secondary to aminoglycoside toxicity. No transfusions were needed. In the morbidly obese patient with symptomatic stones <1.5 cm, ureteroscopic lithotripsy is safe, successful, and efficient.