RT Journal Article SR Electronic T1 Hazards of performing chest compressions in collapsed patients with internal cardioverter defibrillators JF Emergency Medicine Journal JO Emerg Med J FD BMJ Publishing Group Ltd and the British Association for Accident & Emergency Medicine SP 379 OP 380 DO 10.1136/emj.20.4.379 VO 20 IS 4 A1 P A D Clements YR 2003 UL http://emj.bmj.com/content/20/4/379.abstract AB