Hazards of performing chest compressions in collapsed patients with internal cardioverter defibrillators.

CASE REPORT Paramedics were called to a collapsed 75 year old man. They found him in cardiac arrest. Cardiac monitoring demonstrated pulseless electrical activity (PEA) with regular pacing spikes. They identified a device inserted in the left pectoral region. An endotracheal tube was passed and cardiopulmonary resuscitation (CPR) was started. Adrenaline (epinephrine) and atropine were administered. External pacing was started and a palpable pulse was established before transfer to hospital. On arrival at hospital the cardiac output was lost. With the external pacing turned off, the patient was in asystole with the occasional pacing spike. CPR was restarted. After a few minutes the patient was witnessed to jolt during cardiac massage, this recurred a few minutes later. After the second episode it was suspected that the patient was fitted with an ICD and not a pacemaker. This was confirmed when literature on the device was produced by the paramedics. A second rescuer then took over the cardiac massage and after a few minutes the ICD discharged again shocking the rescuer. The rescuer had to rest for over half an hour before being able to resume work. The patient failed to respond to resuscitation attempts. After the resuscitation attempt, the paramedics reported that the patient had jolted twice while they were at the scene. The ICD delivered five shocks during the course of CPR. It was assumed that the cardiac massage mimicked a shockable rhythm that was recognised by the ICD causing it to charge. Four of these shocks had no effect on the two paramedics and first hospital rescuer doctor who were all wearing gloves. However, the fifth shock affected the rescuer who was not wearing gloves. When a representative of the company marketing the ICD attended the hospital to deactivate and remove the device, a print out of its final activity was produced. The timed discharges of the ICD corresponded to the times that the CPR was provided and confirmed that two shocks were delivered on scene and three in hospital. The ICD had begun to charge on a further four occasions but the charge had been dissipated when a “shockable” rhythm disappeared.