Experimental Biology 2010: Prevention Of In Hospital Sudden Cardiac Death With The Use Of Automated External Defibrillators In High Risk Patients

Purpose of Study: The prognosis of in hospital resuscitation of cardiac arrest has not improved significantly over the years. The use of automated external defibrillators (AED) in high risk patients could reduce the chances of sudden cardiac death (SCD) and minimize the associated neurological injury.

Methods Used: Retrospective study done in patients who had SCD in MICU and telemetry units in a community hospital for a period of one year. Age, co-morbid factors admitting diagnosis and the EKG rhythm just before the SCD was reviewed. Hypertension, Diabetes, CAD, CHF, Strokes, Chronic renal failure , COPD, Asthma,, Malignancy, HIV, Hepatitis, Cirrhosis were some of the co-morbid factors considered. Majority of the admitting diagnosis were respiratory failure due to exacerbation of COPD, asthma, pneumonia or CHF; hypotension due to septic shock; diabetic ketoacidosis (DKA), alcohol intoxication, and metabolic abnormalities due to CRF, DKA or drug over dose. Patients who had acute myocardial infarction were excluded from the study.

Summary of Results: 105 patients had SCD with one patient surviving the initial resuscitation but died seven days later due to anoxic encephalopathy. The average age of the patients who had SCD was 69 years and 95% had more than four co-morbid factors. Out of the 105 patients 35 (33.3%) had either ventricular tachycardia or ventricular fibrillation before cardiac arrest and the rest had asystole at the time of cardiac arrest.

Conclusions: Patients who are critically ill, with several co-morbid factors, the likely hood of having SCD is very high. In hospital patients who are at high risk of SCD, placing an AED could reduce the incidence of sudden death by about 30-35%. Further prospective studies should be done in hospitals, which use AED routinely on high risk patients to see if it is cost effective in reducing sudden cardiac deaths.