Out-of-hospital cardiac arrest in the elderly

Background: To investigate the characteristics of out-of-hospital cardiac arrest (OHCA) in the elderly, we retrospectively studied a 6-month series of cases in an emergency department (ED) of a medical center in northern Taiwan. Methods: There were 145 CHCA cases sent to our ED from January 1, 2007 to June 30, 2007. Of these, 28 trauma-related and five pediatric cases were excluded, and 112 cases were eventually enrolled into our study. The 112 cases were divided into an elderly group (>= 65 years) of 81 cases and a non-elderly group of 31 cases. There were 64 males and 48 females (male/female ratio, 1.33:1) aged 24-99 years. We collected the laboratory data and made comparisons between the elderly and non-elderly group in arterial blood gas, hemoglobin, potassium, glucose, and troponin I. We used the statistical software SPSS version 11.5.0 (SPSS Inc., Chicago, IL, USA) with t test analysis. The clinical significance was set at p < 0.05. Results: Return of spontaneous circulation (ROSC) occurred in 46 cases (41%) after standard resuscitation by advanced cardiac life support. The elderly group had a higher ROSC rate than the non-elderly group, but this was not significant (44% vs. 32%; p=0.335). The elderly group had less acidosis, less hypercapnia, less hyperkalemia, less hyperglycemia and a higher rate of elevated troponin I than the non-elderly group, but the differences were not significant. The elderly group had significantly lower hemoglobin levels than the non-elderly group (10.52 +/- 3.04 vs. 12.6 +/- 3.32 g/dL; p = 0.003). The glucose levels of the ROSC group were significantly higher than the non-ROSC group in the elderly (230.14 +/- 130.4 vs. 195.1 +/- 147.7 mg/dL; p=0.049). In the group of acute coronary syndrome (ACS)-related OHCA, the ROSC rate in the elderly group was significantly higher than that of the non-elderly (54.2% vs. 40%; p=0.014). The elderly group had a slightly lower rate of survival than the non-elderly group (7.4% vs. 9.7%; p=0.159). Conclusion: The elderly OHCA cases had an anemic status. The elderly had a higher ROSC rate in cases with relative hyperglycemia and ACS-related OHCA. I his finding provides us with the theory of trialing administration of glucose water during resuscitation in OHCA cases.