[Renal hematomas after extracorporeal lithotripsy with the lithotriptor "lithostar multiline de Siemens"]

Renal haematomas after extracorporeal shockwave lithotrity are an immediate and potentially serious complication. The incidence of post-ESWL renal haematoma with the new Siemens' Lithostar Multiline lithotripter is analyzed in an attempt to know its occurrence, predisposing factors and presentations signs and symptoms.

Between January and December 1998, a total of 1313 extracorporeal shockwave lithotrity sessions were performed on lithiasis located at any level of the urinary tract in 686 patients. Treatment were performed with a Lithostar Multiline lithotripter (electromagnetic generator). The power used ranged from 4 to 9 units, which are power steps based on load tension in Kv, pressure peaks in bars and energy flow density in mJ/mm2, with an average of 3800 pulses/session. A radiological study (ultrasound-tomography) was conducted when faced with clinical suspicion of complications.

A total of 7 clinical renal haematomas (1.02%) were diagnosed. A conservative attitude was taken in most cases. One patient presented hemodynamic instability and required surgery to empty the haematoma and haemostasia of the renal unit, though no nephrectomy was finally required. As predisposing factors: presence of HBP, prior ESWL and hypercholesterolemia are all emphasized. In rare cases several factors concurred simultaneously in the same patient.

Renal haematoma should be suspected in the presence of continuous or unjustified pain after ESWL treatment. Any likely coagulation disorder should be corrected, urinary infections ruled out and pressure figures controlled.