Epidemiologic study of in-hospital cardiopulmonary resuscitation in the elderly

Abstract

Background: It is unknown whether the rate of survival after in-hospital cardiopulmonary resuscitation (CPR) is improving and which characteristics of patients and hospitals predict survival.

Methods: We examined fee-for-service Medicare data from 1992 through 2005 to identify beneficiaries 65 years of age or older who underwent CPR in U.S. hospitals. We examined temporal trends in the incidence of CPR and the rate of survival after CPR, as well as patient- and hospital-level predictors of survival to discharge.

Results: We identified 433,985 patients who underwent in-hospital CPR; 18.3% of these patients (95% confidence interval [CI], 18.2 to 18.5) survived to discharge. The rate of survival did not change substantially during the period from 1992 through 2005. The overall incidence of CPR was 2.73 events per 1000 admissions; the incidence was higher among black and other nonwhite patients. The proportion of patients undergoing in-hospital CPR before death increased over time and was higher for nonwhite patients. The survival rate was lower among patients who were men, were older, had more coexisting illnesses, or were admitted from a skilled-nursing facility. The adjusted odds of survival for black patients were 23.6% lower than those for similar white patients (95% CI, 21.2 to 25.9). The association between race and survival was partially explained by hospital effects: black patients were more likely to undergo CPR in hospitals that have lower rates of post-CPR survival. Among patients surviving in-hospital CPR, the proportion of patients discharged home rather than to a health care facility decreased over time.

Conclusions: Survival after in-hospital CPR did not improve from 1992 through 2005. The proportion of in-hospital deaths preceded by CPR increased, whereas the proportion of survivors discharged home after undergoing CPR decreased. Black race was associated with higher rates of CPR but lower rates of survival after CPR.

Figure 1. Survival to Hospital Discharge Following In-Hospital CPR by Year and Race

Survival is poorer for non-white individuals. There is no significant trend in overall survival 1992-2005 (Likelihood ratio p=0.569).

Figure 2. Trends in CPR Utilization, by Race

A. Incidence of in-hospital CPR. The incidence of in-hospital CPR is higher for non-white individuals. There is a clinically insignificant but statistically significant positive linear trend in incidence when considering all patients 1992-2005 (p <0.001). B. Deaths following in-hospital CPR as a percentage of all hospital deaths. The percentage of dying patients receiving CPR prior to death is increasing, and is higher for non-white individuals. The linear trend, considering all patients, is highly statistically significant (p<0.001).

Figure 2. Trends in CPR Utilization, by Race

A. Incidence of in-hospital CPR. The incidence of in-hospital CPR is higher for non-white individuals. There is a clinically insignificant but statistically significant positive linear trend in incidence when considering all patients 1992-2005 (p <0.001). B. Deaths following in-hospital CPR as a percentage of all hospital deaths. The percentage of dying patients receiving CPR prior to death is increasing, and is higher for non-white individuals. The linear trend, considering all patients, is highly statistically significant (p<0.001).

Figure 3. Trends in Discharge Destination of Survivors of In-Hospital CPR

Patients discharged home with or without home health or home IV services were included in the “Home” group. Patients discharged to a skilled nursing facility under Medicare or Medicaid were included in the “Skilled Nursing Facility” group. Patients discharged to another acute care hospital, intermediate care facility, long-term care hospital, swing bed within the same hospital, or a rehabilitation hospital were included in the “Another Hospital” group. The “Hospice” group included those discharged to hospice at home or a medical facility, and was used for years 1997 and beyond. All trends were highly statistically significant (p<0.001).