Patient Safety Advisory Reprinted from the PA-PSRS Patient Safety Advisory—Vol. 2, No. 1 (March 2005) Produced by ECRI & ISMP under contract to the Pennsylvania Patient Safety Authority Risk of Arrhythmia During Activation of Electrohydraulic Lithotripter P A-PSRS has received a report of a patient ex- periencing premature ventricular contractions (PVCs) during a procedure involving an intracorporeal In 1982, ECRI published a Hazard Report concerning anesthetists receiving electrical shocks during EHL bladder stone removal procedures.1 Based on the electrohydraulic lithotripter (EHL). According to the hospital reports, ECRI conducted experiments with hospital, a PVC occurred each time the EHL was acti- several EHL device models. They determined that the vated. magnitude of the electric current was sufficient to be perceived by a locally anesthetized patient or a clini- The lithotripter electrode is inserted through the ure- cian who becomes part of the current’s path to thra using a cystoscope to remove stones from the ground. The 1982 reports also described the possible bladder or nephroscope to remove stones from the occurrence of an electrical path to ground for stray kidney. With saline used for irrigation and the elec- lithotripter current from an intracardiac catheter or trode placed near the bladder or kidney stone, the electrode. ECRI stated that the occurrence was rare, lithotripter is activated, generating a series of high- but potentially hazardous. With the use of an intracar- voltage sparks at the electrode tip. Sparks in the liq- diac or pacemaker catheter, the electrical pathway for uid medium generate a series of hydraulic shock current would be directed through cardiac tissue, pos- waves, causing the stone to fracture. sibly resulting in cardiac arrhythmias. Cardiac arrhythmias, though rare, can occur during Methods that can help to mitigate the problem of elec- EHL procedures. A review of FDA’s Manufacturer and trical shocks or arrhythmias include: User Facility Device Experience (MAUDE) database, from 1992 to the present, revealed three reports of • Informing surgical staff of the possibility of shocks patients’ experiencing abnormal cardiac rhythms dur- or cardiac arrhythmias occurring during EHL pro- ing activation of the EHL generator. In two reports, cedures. patients experienced asystole. The rhythm returned to normal sinus rhythm when the EHL device was turned • Avoiding physical contact as much as possible off. In the third report, the patient’s heart rate de- between surgical staff and patients during activa- creased, and the procedure was aborted with no re- tion of the EHL device. ported injury to the patient. • Minimizing patient contact with grounded metal Respective EHL device manufacturers’ responses in surfaces during procedures. the MAUDE reports did not include definitive causes, but did suggest possible causes for the abnormalities • Avoiding EHL device use on patients who have in two of the three reports. One report in which the externally connected intracardiac catheters. patient experienced asystole included a potential cause: that the patient was electrically grounded Notes through the anesthesiologist, who may have been in 1. ECRI. Electrohydraulic Lithotripters [Hazard Report]. Health Devices 1982 Dec;12(2):46-7. physical contact with the patient during activation of the device. In the report concerning the patient’s de- creased heart rate, the suggested cause was that the patient may have been electrically grounded through the patient electrodes and lead wires to the physiol- This article is reprinted from the PA-PSRS Patient Safety Advisory, Vol. 2, No. ogic monitoring system used to monitor the patient’s 1—March 2005. The Advisory is a publication of the Pennsylvania Patient vital signs during the procedure. Safety Authority, produced by ECRI & ISMP under contract to the Authority as part of the Pennsylvania Patient Safety Reporting System (PA-PSRS). A review of MAUDE, also from 1992 to the present, revealed approximately 25 reports of electrical shocks Copyright 2005 by the Patient Safety Authority. This publication may be re- printed and distributed without restriction, provided it is printed or distributed in experienced by the patient, anesthesiologist, surgeon, its entirety and without alteration. Individual articles may be reprinted in their or a combination of individuals during EHL device entirety and without alteration provided the source is clearly attributed. activation. To see other articles or issues of the Advisory, visit our web site at www.psa.state.pa.us. Click on “Advisories” in the left-hand menu bar. ©2005 Pennsylvania Patient Safety Authority Page 1 Reprinted from the PA-PSRS Patient Safety Advisory—Vol. 2, No. 1 (March 2005) An Independent Agency of the Commonwealth of Pennsylvania The Patient Safety Authority is an independent state agency created by Act 13 of 2002, the Medical Care Availability and Reduction of Error (“Mcare”) Act. Consistent with Act 13, ECRI, as contractor for the PA-PSRS program, is issuing this newsletter to advise medical facilities of immediate changes that can be instituted to reduce serious events and incidents. For more information about the PA- PSRS program or the Patient Safety Authority, see the Authority’s website at www.psa.state.pa.us. ECRI is an independent, nonprofit health services research agency dedicated to improving the safety, efficacy and cost-effectiveness of healthcare. ECRI’s focus is healthcare technology, healthcare risk and quality management and healthcare environmental management. ECRI provides information services and technical assistance to more than 5,000 hospitals, healthcare organizations, ministries of health, government and planning agencies, and other organizations worldwide. The Institute for Safe Medication Practices (ISMP) is an independent, nonprofit organization dedicated solely to medication error prevention and safe medication use. ISMP provides recommendations for the safe use of medications to the healthcare community including healthcare professionals, government agencies, accrediting organizations, and consumers. ISMP's efforts are built on a non-punitive approach and systems-based solutions. Page 2 ©2005 Pennsylvania Patient Safety Authority