Renal hematoma after shockwave extracorporeal lithotripsy

OBJECTIVE: Renal haematomas after shock wave extracorporeal lithotripsy (SWEL) represent a potentially serious complication. This paper examines those cases of post-SWEL renal haematoma seen in our Centre, analyzing the likely risk factors. PATIENTS AND METHODS: Between May 1988 and June 1996, 12,800 patients were treated with 15100 lithiasis at some level of the urinary tract requiring 16,000 SWEL sessions. All treatments were done with a Dornier HM-4 lithotripter. Voltage applied ranged from 18 to 26 Kv, averaging 2500 waves/session. Complementary testing (ultrasound/computerised tomography) was requested immediately after treatment if clinical complications were suspected. RESULTS: A total of 10 renal haematomas (0.078%) were diagnosed. Six cases were mild, but 4 presented extensive haematoma with significant haemodynamic consequence. Although in one case nephrectomy was undertaken to control haemorrhage, death finally occurred by disseminated intravascular coagulation. Four patients who developed haematoma were hypertensive and 3 had a previously corrected haemostasis alteration. CONCLUSIONS: The possibility of renal haematoma should be taken into account in the face of persistent and unjustified pain after SWEL treatment. Normalization of blood pressure values, correction of urinary infection as well as adequate correction of haemostatic disorders is advisable.