LITHOTRIPSY CAUSES SEVERE BURN

Case Overview:
Pt is a 50 y/o woman with a history of hypertension, smoker, stroke, melanoma, cellulitis.  She presented to her surgeon for cellulitis and they did a work-up for recurrent cancer which revealed a large kidney stone causing obstruction.  On 3/18/12 she was admitted to Hospital for extracorporeal shock wave lithotripsy (ESWL) which was complicated by a left flank burn and non- fracturing of the left stone. She claims the doctor left the room during the procedure and the tech continued the procedure. Later the doctor informed her that the machine malfunctioned, stating that the heat sensors were faulty.

I have just reviewed the UofL records and added them to casemap with updated summary attached. The OR report for the ESWL procedure states that approximately 3,000 shocks were applied to the stone without incident. Once they removed the Lithotripter, they noted a large raised burned area. It was treated immediately in the OR by Dr. Ankem, and then referred to the surgical team and burn specialists for treatment. The kidney foundation website states that 1-2 thousand shock waves are typically needed to crush a stone while other sources reference 2500 to 4000 being the upward limit.

During her stay, she was seen by the director of risk management who told her that a report would be made to the FDA under the Safe Medical Devices Act and that Lithotripsy LLC was notified.

She suffered from 1st and 2nd degree burns to 4% of her total body surface in the flank area. Doctors recommended surgical debridement but she was hesitant to undergo more surgery and opted for wound dressings and burn physical therapy. She suffered considerable pain during the six months of treatment.

I’ve only been able to find one source of a similar incident documented in the attached 2/2012 article from the British Journal of Urology. The author states that to his knowledge this case is the first documenting second degree burns after ESWL. He noted that the amount of shocks used might be considered marginally high. In addition, he noted that conventional ultrasound gel was used in lieu of standard coupling gel approved for use with the Medispec lithotripter. The higher viscosity of the gel used might have caused further attenuation of the energy transmission to the patient. Supposedly in this case the lithotripter was inspected by the manufacturer and no defects were found.

Issue:
Need to determine whether the machine was at fault. Pt had significant burn area, we have photos that we can forward if that would help.

MEDQUEST EXPERT RESPONSES:
Very unusual complication, but negligence lies somewhere. 3000 shocks not unusual, but at what power settings? Case worthy of review. DR JP – Urologist

Sounds like a good case I am on the allied litho board of directors for trip state region.  I never came across this either could be the gel more than the shock number.  Doc leaving rm not causative Dr MB – Urologist