Paul S. Chan

Rapid Response Teams: A Systematic Review and Meta-analysis

BACKGROUND Although rapid response teams (RRTs) increasingly have been adopted by hospitals, their effectiveness in reducing hospital mortality remains uncertain. We conducted a meta-analysis to assess the effect of RRTs on reducing cardiopulmonary arrest and hospital mortality rates. METHODS We conducted a systematic review of studies published from January 1, 1950, through November 31, 2008, using PubMed, EMBASE, Web of Knowledge, CINAHL, and all Evidence-Based Medicine Reviews. Randomized clinical trials and prospective studies of RRTs that reported data on changes in the primary outcome of hospital mortality or the secondary outcome of cardiopulmonary arrest cases were included. RESULTS Eighteen studies from 17 publications (with 1 treated as 2 separate studies) were identified, involving nearly 1.3 million hospital admissions. Implementation of an RRT in adults was associated with a 33.8% reduction in rates of cardiopulmonary arrest outside the intensive care unit (ICU) (relative risk [RR], 0.66; 95% confidence interval [CI], 0.54-0.80) but was not associated with lower hospital mortality rates (RR, 0.96; 95% CI, 0.84-1.09). In children, implementation of an RRT was associated with a 37.7% reduction in rates of cardiopulmonary arrest outside the ICU (RR, 0.62; 95% CI, 0.46-0.84) and a 21.4% reduction in hospital mortality rates (RR, 0.79; 95% CI, 0.63-0.98). The pooled mortality estimate in children, however, was not robust to sensitivity analyses. Moreover, studies frequently found evidence that deaths were prevented out of proportion to reductions in cases of cardiopulmonary arrest, raising questions about mechanisms of improvement. CONCLUSION Although RRTs have broad appeal, robust evidence to support their effectiveness in reducing hospital mortality is lacking.

Delayed time to defibrillation after in-hospital cardiac arrest

BACKGROUND Expert guidelines advocate defibrillation within 2 minutes after an in-hospital cardiac arrest caused by ventricular arrhythmia. However, empirical data on the prevalence of delayed defibrillation in the United States and its effect on survival are limited. METHODS We identified 6789 patients who had cardiac arrest due to ventricular fibrillation or pulseless ventricular tachycardia at 369 hospitals participating in the National Registry of Cardiopulmonary Resuscitation. Using multivariable logistic regression, we identified characteristics associated with delayed defibrillation. We then examined the association between delayed defibrillation (more than 2 minutes) and survival to discharge after adjusting for differences in patient and hospital characteristics. RESULTS The overall median time to defibrillation was 1 minute (interquartile range, <1 to 3 minutes); delayed defibrillation occurred in 2045 patients (30.1%). Characteristics associated with delayed defibrillation included black race, noncardiac admitting diagnosis, and occurrence of cardiac arrest at a hospital with fewer than 250 beds, in an unmonitored hospital unit, and during after-hours periods (5 p.m. to 8 a.m. or weekends). Delayed defibrillation was associated with a significantly lower probability of surviving to hospital discharge (22.2%, vs. 39.3% when defibrillation was not delayed; adjusted odds ratio, 0.48; 95% confidence interval, 0.42 to 0.54; P<0.001). In addition, a graded association was seen between increasing time to defibrillation and lower rates of survival to hospital discharge for each minute of delay (P for trend <0.001). CONCLUSIONS Delayed defibrillation is common and is associated with lower rates of survival after in-hospital cardiac arrest.

Trends in Survival after In-Hospital Cardiac Arrest

BACKGROUND Despite advances in resuscitation care in recent years, it is not clear whether survival and neurologic function after in-hospital cardiac arrest have improved over time. METHODS We identified all adults who had an in-hospital cardiac arrest at 374 hospitals in the Get with the Guidelines-Resuscitation registry between 2000 and 2009. Using multivariable regression, we examined temporal trends in risk-adjusted rates of survival to discharge. Additional analyses explored whether trends were due to improved survival during acute resuscitation or postresuscitation care and whether they occurred at the expense of greater neurologic disability in survivors. RESULTS Among 84,625 hospitalized patients with cardiac arrest, 79.3% had an initial rhythm of asystole or pulseless electrical activity, and 20.7% had ventricular fibrillation or pulseless ventricular tachycardia. The proportion of cardiac arrests due to asystole or pulseless electrical activity increased over time (P<0.001 for trend). Risk-adjusted rates of survival to discharge increased from 13.7% in 2000 to 22.3% in 2009 (adjusted rate ratio per year, 1.04; 95% confidence interval [CI], 1.03 to 1.06; P<0.001 for trend). Survival improvement was similar in the two rhythm groups and was due to improvement in both acute resuscitation survival and postresuscitation survival. Rates of clinically significant neurologic disability among survivors decreased over time, with a risk-adjusted rate of 32.9% in 2000 and 28.1% in 2009 (adjusted rate ratio per year, 0.98; 95% CI, 0.97 to 1.00; P=0.02 for trend). CONCLUSIONS Both survival and neurologic outcomes after in-hospital cardiac arrest have improved during the past decade at hospitals participating in a large national quality-improvement registry. (Funded by the American Heart Association.).

Appropriateness of Percutaneous Coronary Intervention

CONTEXT Despite the widespread use of percutaneous coronary intervention (PCI), the appropriateness of these procedures in contemporary practice is unknown. OBJECTIVE To assess the appropriateness of PCI in the United States. DESIGN, SETTING, AND PATIENTS Multicenter, prospective study of patients within the National Cardiovascular Data Registry undergoing PCI between July 1, 2009, and September 30, 2010, at 1091 US hospitals. The appropriateness of PCI was adjudicated using the appropriate use criteria for coronary revascularization. Results were stratified by whether the procedure was performed for an acute (ST-segment elevation myocardial infarction, non-ST-segment elevation myocardial infarction, or unstable angina with high-risk features) or nonacute indication. MAIN OUTCOME MEASURES Proportion of acute and nonacute PCIs classified as appropriate, uncertain, or inappropriate; extent of hospital-level variation in inappropriate procedures. RESULTS Of 500,154 PCIs, 355,417 (71.1%) were for acute indications (ST-segment elevation myocardial infarction, 103,245 [20.6%]; non-ST-segment elevation myocardial infarction, 105,708 [21.1%]; high-risk unstable angina, 146,464 [29.3%]), and 144,737 (28.9%) for nonacute indications. For acute indications, 350,469 PCIs (98.6%) were classified as appropriate, 1055 (0.3%) as uncertain, and 3893 (1.1%) as inappropriate. For nonacute indications, 72,911 PCIs (50.4%) were classified as appropriate, 54,988 (38.0%) as uncertain, and 16,838 (11.6%) as inappropriate. The majority of inappropriate PCIs for nonacute indications were performed in patients with no angina (53.8%), low-risk ischemia on noninvasive stress testing (71.6%), or suboptimal (≤1 medication) antianginal therapy (95.8%). Furthermore, although variation in the proportion of inappropriate PCI across hospitals was minimal for acute procedures, there was substantial hospital variation for nonacute procedures (median hospital rate for inappropriate PCI, 10.8%; interquartile range, 6.0%-16.7%). CONCLUSIONS In this large contemporary US cohort, nearly all acute PCIs were classified as appropriate. For nonacute indications, however, 12% were classified as inappropriate, with substantial variation across hospitals.

Health Literacy and Outcomes Among Patients With Heart Failure

CONTEXT Little is known about the effects of low health literacy among patients with heart failure, a condition that requires self-management and frequent interactions with the health care system. OBJECTIVE To evaluate the association between low health literacy and all-cause mortality and hospitalization among outpatients with heart failure. DESIGN, SETTING, AND PATIENTS Retrospective cohort study conducted at Kaiser Permanente Colorado, an integrated managed care organization. Outpatients with heart failure were identified between January 2001 and May 2008, were surveyed by mail, and underwent follow-up for a median of 1.2 years. Health literacy was assessed using 3 established screening questions and categorized as adequate or low. Responders were excluded if they did not complete at least 1 health literacy question or if they did not have at least 1 year of enrollment prior to the survey date. MAIN OUTCOME MEASURES All-cause mortality and all-cause hospitalization. RESULTS Of the 2156 patients surveyed, 1547 responded (72% response rate). Of 1494 included responders, 262 (17.5%) had low health literacy. Patients with low health literacy were older, of lower socioeconomic status, less likely to have at least a high school education, and had higher rates of coexisting illnesses. In multivariable Cox regression, low health literacy was independently associated with higher mortality (unadjusted rate, 17.6% vs 6.3%; adjusted hazard ratio, 1.97 [95% confidence interval, 1.3-2.97]; P = .001) but not hospitalization (unadjusted rate, 30.5% vs 23.2%; adjusted hazard ratio, 1.05 [95% confidence interval, 0.8-1.37]; P = .73). CONCLUSION Among patients with heart failure in an integrated managed care organization, low health literacy was significantly associated with higher all-cause mortality.

Association between Stroke Center Hospitalization for Acute Ischemic Stroke and Mortality

CONTEXT Although stroke centers are widely accepted and supported, little is known about their effect on patient outcomes. OBJECTIVE To examine the association between admission to stroke centers for acute ischemic stroke and mortality. DESIGN, SETTING, AND PARTICIPANTS Observational study using data from the New York Statewide Planning and Research Cooperative System. We compared mortality for patients admitted with acute ischemic stroke (n = 30,947) between 2005 and 2006 at designated stroke centers and nondesignated hospitals using differential distance to hospitals as an instrumental variable to adjust for potential prehospital selection bias. Patients were followed up for mortality for 1 year after the index hospitalization through 2007. To assess whether our findings were specific to stroke, we also compared mortality for patients admitted with gastrointestinal hemorrhage (n = 39,409) or acute myocardial infarction (n = 40,024) at designated stroke centers and nondesignated hospitals. MAIN OUTCOME MEASURE Thirty-day all-cause mortality. RESULTS Among 30,947 patients with acute ischemic stroke, 15,297 (49.4%) were admitted to designated stroke centers. Using the instrumental variable analysis, admission to designated stroke centers was associated with lower 30-day all-cause mortality (10.1% vs 12.5%; adjusted mortality difference, -2.5%; 95% confidence interval [CI], -3.6% to -1.4%; P < .001) and greater use of thrombolytic therapy (4.8% vs 1.7%; adjusted difference, 2.2%; 95% CI, 1.6% to 2.8%; P < .001). Differences in mortality also were observed at 1-day, 7-day, and 1-year follow-up. The outcome differences were specific for stroke, as stroke centers and nondesignated hospitals had similar 30-day all-cause mortality rates among those with gastrointestinal hemorrhage (5.0% vs 5.8%; adjusted mortality difference, +0.3%; 95% CI, -0.5% to 1.0%; P = .50) or acute myocardial infarction (10.5% vs 12.7%; adjusted mortality difference, +0.1%; 95% CI, -0.9% to 1.1%; P = .83). CONCLUSION Among patients with acute ischemic stroke, admission to a designated stroke center was associated with modestly lower mortality and more frequent use of thrombolytic therapy.

Duration of resuscitation efforts and survival after in-hospital cardiac arrest: an observational study

BACKGROUND During in-hospital cardiac arrests, how long resuscitation attempts should be continued before termination of efforts is unknown. We investigated whether duration of resuscitation attempts varies between hospitals and whether patients at hospitals that attempt resuscitation for longer have higher survival rates than do those at hospitals with shorter durations of resuscitation efforts. METHODS Between 2000 and 2008, we identified 64,339 patients with cardiac arrests at 435 US hospitals within the Get With The Guidelines—Resuscitation registry. For each hospital, we calculated the median duration of resuscitation before termination of efforts in non-survivors as a measure of the hospitals overall tendency for longer attempts. We used multilevel regression models to assess the association between the length of resuscitation attempts and risk-adjusted survival. Our primary endpoints were immediate survival with return of spontaneous circulation during cardiac arrest and survival to hospital discharge. FINDINGS 31,198 of 64,339 (48·5%) patients achieved return of spontaneous circulation and 9912 (15·4%) survived to discharge. For patients achieving return of spontaneous circulation, the median duration of resuscitation was 12 min (IQR 6-21) compared with 20 min (14-30) for non-survivors. Compared with patients at hospitals in the quartile with the shortest median resuscitation attempts in non-survivors (16 min [IQR 15-17]), those at hospitals in the quartile with the longest attempts (25 min [25-28]) had a higher likelihood of return of spontaneous circulation (adjusted risk ratio 1·12, 95% CI 1·06-1·18; p<0·0001) and survival to discharge (1·12, 1·02-1·23; 0·021). INTERPRETATION Duration of resuscitation attempts varies between hospitals. Although we cannot define an optimum duration for resuscitation attempts on the basis of these observational data, our findings suggest that efforts to systematically increase the duration of resuscitation could improve survival in this high-risk population. FUNDING American Heart Association, Robert Wood Johnson Foundation Clinical Scholars Program, and the National Institutes of Health.

Recent Trends in Survival From Out-of-Hospital Cardiac Arrest in the United States

Background— Despite intensive efforts over many years, the United States has made limited progress in improving rates of survival from out-of-hospital cardiac arrest. Recently, national organizations, such as the American Heart Association, have focused on promoting bystander cardiopulmonary resuscitation, use of automated external defibrillators, and other performance improvement efforts. Methods and Results— Using the Cardiac Arrest Registry to Enhance Survival (CARES), a prospective clinical registry, we identified 70 027 U.S. patients who experienced an out-of-hospital cardiac arrest between October 2005 and December 2012. Using multilevel Poisson regression, we examined temporal trends in risk-adjusted survival. After adjusting for patient and cardiac arrest characteristics, risk-adjusted rates of out-of-hospital cardiac arrest survival increased from 5.7% in the reference period of 2005 to 2006 to 7.2% in 2008 (adjusted risk ratio, 1.27; 95% confidence interval, 1.12–1.43; P<0.001). Survival improved more modestly to 8.3% in 2012 (adjusted risk ratio, 1.47; 95% confidence interval, 1.26–1.70; P<0.001). This improvement in survival occurred in both shockable and nonshockable arrest rhythms (P for interaction=0.22) and was also accompanied by better neurological outcomes among survivors (P for trend=0.01). Improved survival was attributable to both higher rates of prehospital survival, where risk-adjusted rates increased from 14.3% in 2005 to 2006 to 20.8% in 2012 (P for trend<0.001), and in-hospital survival (P for trend=0.015). Rates of bystander cardiopulmonary resuscitation and automated external defibrillator use modestly increased during the study period and partly accounted for prehospital survival trends. Conclusions— Data drawn from a large subset of U.S communities suggest that rates of survival from out-of-hospital cardiac arrest have improved among sites participating in a performance improvement registry.

The Association of Cognitive and Somatic Depressive Symptoms With Depression Recognition and Outcomes After Myocardial Infarction

Background—Among patients with acute myocardial infarction (AMI), depression is both common and underrecognized. The association of different manifestations of depression, somatic and cognitive, with depression recognition and long-term prognosis is poorly understood. Methods and Results—Depression was confirmed in 481 AMI patients enrolled from 21 sites during their index hospitalization with a Patient Health Questionnaire (PHQ-9) score ≥10. Within the PHQ-9, separate somatic and cognitive symptom scores were derived, and the independent association between these domains and the clinical recognition of depression, as documented in the medical records, was evaluated. In a separate multisite AMI registry of 2347 patients, the association between somatic and cognitive depressive symptoms and 4-year all-cause mortality and 1-year all-cause rehospitalization was evaluated. Depression was clinically recognized in 29% (n=140) of patients. Cognitive depressive symptoms (relative risk per SD increase, 1.14; 95% CI, 1.03 to 1.26; P=0.01) were independently associated with depression recognition, whereas the association for somatic symptoms and recognition (relative risk, 1.04; 95% CI, 0.87 to 1.26; P=0.66) was not significant. However, unadjusted Cox regression analyses found that only somatic depressive symptoms were associated with 4-year mortality (hazard ratio [HR] per SD increase, 1.22; 95% CI, 1.08 to 1.39) or 1-year rehospitalization (HR, 1.22; 95% CI, 1.11 to 1.33), whereas cognitive manifestations were not (HR for mortality, 1.01; 95% CI, 0.89 to 1.14; HR for rehospitalization, 1.01; 95% CI, 0.93 to 1.11). After multivariable adjustment, the association between somatic symptoms and rehospitalization persisted (HR, 1.16; 95% CI, 1.06 to 1.27; P=0.01) but was attenuated for mortality (HR, 1.07; 95% CI, 0.94 to 1.21; P=0.30). Conclusions—Depression after AMI was recognized in fewer than 1 in 3 patients. Although cognitive symptoms were associated with recognition of depression, somatic symptoms were associated with long-term outcomes. Comprehensive screening and treatment of both somatic and cognitive symptoms may be necessary to optimize depression recognition and treatment in AMI patients.

Survival Trends in Pediatric In-Hospital Cardiac Arrests: An Analysis From Get With The Guidelines–Resuscitation

Background— Despite ongoing efforts to improve the quality of pediatric resuscitation, it remains unknown whether survival in children with in-hospital cardiac arrest has improved. Methods and Results— Between 2000 and 2009, we identified children (<18 years of age) with an in-hospital cardiac arrest at hospitals with >3 years of participation and >5 cases annually within the national Get With The Guidelines–Resuscitation registry. Multivariable logistic regression was used to examine temporal trends in survival to discharge. We also explored whether trends in survival were attributable to improvement in acute resuscitation or postresuscitation care and examined trends in neurological disability among survivors. Among 1031 children at 12 hospitals, the initial cardiac arrest rhythm was asystole and pulseless electrical activity in 874 children (84.8%) and ventricular fibrillation and pulseless ventricular tachycardia in 157 children (15.2%), with an increase in cardiac arrests due to pulseless electrical activity over time (P for trend <0.001). Risk-adjusted rates of survival to discharge increased from 14.3% in 2000 to 43.4% in 2009 (adjusted rate ratio per year, 1.08; 95% confidence interval, 1.01–1.16; P for trend=0.02). Improvement in survival was driven largely by an improvement in acute resuscitation survival (risk-adjusted rates: 42.9% in 2000, 81.2% in 2009; adjusted rate ratio per year: 1.04; 95% confidence interval, 1.01–1.08; P for trend=0.006). Moreover, survival trends were not accompanied by higher rates of neurological disability among survivors over time (unadjusted P for trend=0.32), suggesting an overall increase in the number of survivors without neurological disability over time. Conclusions— Rates of survival to hospital discharge in children with in-hospital cardiac arrests have improved over the past decade without higher rates of neurological disability among survivors.