PURPOSE: Following the introduction of automated external defibrillators [AED] to the “chain of survival” and evidence of their benefit in the pre-hospital setting, many hospitals introduced AEDs. This study reports the findings of an audit conducted to assess the first 3 years of use of AEDs in a large teaching hospital.
METHODS: A retrospective chart review was conducted for the period following the installations of AEDs on Oct 1, 2006 until December 31, 2009. Patients for inclusion in the audit were identified from the log of code blues maintained by locating. Chart abstraction was conducted by a trained research assistant (GC) with quality checks performed (MC). Data was entered into an Excel spreadsheet and analyzed with STATA.
RESULTS: During the study period there were 298 code blues, medical records could be located for 292 patients. Code documentation was poor with only 17.6% of code records fully complete. However, data regarding AED use could be determined on the majority of charts. Overall 82.6% of the documented codes were witnessed, 39.2% of patients were in cardiac arrest when the code team arrived, and overall 76.2% of patients were alive at the end of the code but only 50% of those initially found pulseless. The overall AED rate of use in unresponsive or pulseless patients was 35.9% and ranged between 29.4% to 44% over the study period. Survival rates at the end of the code were higher when AEDs were not used, or not documented to have been used, compared to when AEDs were used; overall (84.5% vs 56.1%, p <0.0001), when patients were unconscious or pulseless (76.1% vs 47.7%, p = 0.0002), when pulseless (61.8% vs 40.9%, p = 0.0449), and when the first documented rhythm was VF or VT (90.0% vs 62.5%, p = 0.2745).
CONCLUSIONS: This study revealed that although AED use was low, it was associated with lower rates of survival. The findings may be contrary to results from pre-hospital AED studies due to differences in the populations. Additionally, the application of an AED within the hospital setting may a surrogate measure for a delay in the arrival of the code blue team. Unfortunately due to poor documentation it is not possible to fully investigate possible explanations for the findings within this study
CLINICAL IMPLICATIONS: The role of AED in the in-hospital chain of survival must be further investigated to determine if evidence exists to support their ongoing inclusion.
DISCLOSURE: The following authors have nothing to disclose: Gary Carbell, Michael Christian
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