Advanced cardiac life support (ACLS) guidelines from the American Heart Association (AHA) now recommend not checking for a pulse between the initial three defibrillations for pulseless patients in ventricular tachycardia or fibrillation. The AHA asserts that checking for a pulse needlessly delays defibrillation. This study was undertaken to determine if pulse checks delay defibrillation by EMT-Defibrillators (EMT-Ds) using a semiautomatic defibrillator (SAED). Twenty-seven EMT-Ds demonstrated delivery of three successive defibrillations during two test scenarios: once with and once without pulse checks after the first and second defibrillations. The time from the first to third defibrillation was recorded. The mean time to deliver the defibrillations was 60.2 +/- 6.2 seconds with pulse checks and 57.5 +/- 4.6 seconds without pulse checks. The difference, 2.7 +/- 5.9 seconds, was statistically significant (P = 0.026). Pulse checks by EMT-Ds do delay administration of defibrillations, but consideration should be given to reinstating pulse checks as a part of the AHA guidelines, since this delay is of questionable clinical significance.