Factors associated with re-arrest following initial resuscitation from cardiac arrest.

BACKGROUND: To examine patient- and arrest-level factors associated with the incidence of re-arrest in the hospital setting, and to measure the association between re-arrest and survival to discharge. METHODS: This work represents a retrospective cohort study of adult patients who were successfully resuscitated from an initial out-of-hospital cardiac arrest (OHCA) or in-hospital cardiac arrest (ICHA) of non-traumatic origin at two urban academic medical centers. In this study, re-arrest was defined as loss of a pulse following 20min of sustained return of spontaneous circulation (ROSC). RESULTS: Between 01/2005 and 04/2016, 1961 patients achieved ROSC following non-traumatic cardiac arrest. Of those, 471 (24%) experienced at least one re-arrest. In re-arrest patients, the median time from initial ROSC to first re-arrest was 5.4h (IQR: 1.1, 61.8). The distribution of initial rhythms between single- and re-arrest patients did not vary, nor did the median duration of initial arrest. Among 108 re-arrest patients with an initial shockable rhythm, 60 (56%) experienced a shockable re-arrest rhythm. Among 273 with an initial nonshockable rhythm, 31 (11%) experienced a shockable re-arrest rhythm. After adjusting for significant covariates, the incidence of re-arrest was associated with a lower likelihood of survival to discharge (OR: 0.32; 95% CI: 0.24-0.43; p<0.001). CONCLUSIONS: Re-arrest is a common complication experienced by cardiac arrest patients that achieve ROSC, and occurs early in the course of their post-arrest care. Moreover, re-arrest is associated with a decreased likelihood of survival to discharge, even after adjustments for relevant covariates.

Inter-rater reliability of post-arrest cerebral performance category (CPC) scores.

PURPOSE: Cerebral Performance Category (CPC) scores are often an outcome measure for post-arrest neurologic function, collected worldwide to compare performance, evaluate therapies, and formulate recommendations. At most institutions, no formal training is offered in their determination, potentially leading to misclassification. MATERIALS AND METHODS: We identified 171 patients at 2 hospitals between 5/10/2005 and 8/31/2012 with two CPC scores at hospital discharge recorded independently - in an in-house quality improvement database and as part of a national registry. Scores were abstracted retrospectively from the same electronic medical record by two separate non-clinical researchers. These scores were compared to assess inter-rater reliability and stratified based on whether the score was concordant or discordant among reviewers to determine factors related to discordance. RESULTS: Thirty-nine CPC scores (22.8%) were discordant (kappa: 0.66), indicating substantial agreement. When dichotomized into "favorable" neurologic outcome (CPC 1-2)/"unfavorable" neurologic outcome (CPC 3-5), 20 (11.7%) scores were discordant (kappa: 0.70), also indicating substantial agreement. Patients discharged home (as opposed to nursing/other care facility) and patients with suspected cardiac etiology of arrest were statistically more likely to have concordant scores. For the quality improvement database, patients with discordant scores had a statistically higher median CPC score than those with concordant scores. The registry had statistically lower median CPC score (CPC 1) than the quality improvement database (CPC 2); p<0.01 for statistical significance. CONCLUSIONS: CPC scores have substantial inter-rater reliability, which is reduced in patients who have worse outcomes, have a non-cardiac etiology of arrest, and are discharged to a location other than home.

Quantitative relationship between end-tidal carbon dioxide and CPR quality during both in-hospital and out-of-hospital cardiac arrest.

OBJECTIVE: Cardiopulmonary resuscitation (CPR) guidelines recommend the administration of chest compressions (CC) at a standardized rate and depth without guidance from patient physiologic output. The relationship between CC performance and actual CPR-generated blood flow is poorly understood, limiting the ability to define "optimal" CPR delivery. End-tidal carbon dioxide (ETCO2) has been proposed as a surrogate measure of blood flow during CPR, and has been suggested as a tool to guide CPR despite a paucity of clinical data. We sought to quantify the relationship between ETCO2 and CPR characteristics during clinical resuscitation care. METHODS: Multicenter cohort study of 583 in- and out-of-hospital cardiac arrests with time-synchronized ETCO2 and CPR performance data captured between 4/2006 and 5/2013. ETCO2, ventilation rate, CC rate and depth were averaged over 15-s epochs. A total of 29,028 epochs were processed for analysis using mixed-effects regression techniques. RESULTS: CC depth was a significant predictor of increased ETCO2. For every 10mm increase in depth, ETCO2 was elevated by 1.4mmHg (p<.001). For every 10 breaths/min increase in ventilation rate, ETCO2 was lowered by 3.0mmHg (p<.001). CC rate was not a predictor of ETCO2 over the dynamic range of actual CC delivery. Case-averaged ETCO2 values in patients with return of spontaneous circulation were higher compared to those who did not have a pulse restored (34.5±4.5 vs 23.1±12.9mmHg, p<.001). CONCLUSIONS: ETCO2 values generated during CPR were statistically associated with CC depth and ventilation rate. Further studies are needed to assess ETCO2 as a potential tool to guide care.

Cerebral performance category at hospital discharge predicts long-term survival of cardiac arrest survivors receiving targeted temperature management*.

OBJECTIVE: Despite recent advancements in post-cardiac arrest resuscitation, the optimal measurement of postarrest outcome remains unclear. We hypothesized that Cerebral Performance Category score can predict the long-term outcome of postarrest survivors who received targeted temperature management during their postarrest hospital care. DESIGN: Retrospective chart review. SETTING: Two academic medical centers from May 2005 to December 2012. PATIENTS: The medical records of 2,417 out-of-hospital and in-hospital patients post cardiac arrest were reviewed to identify 140 of 582 survivors who received targeted temperature management. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The Cerebral Performance Category scores at hospital discharge were determined by three independent abstractors. The 1-month, 6-month, and 12-month survival of these patients was determined by reviewing hospital records and querying the Social Security Death Index and by follow-up telephone calls. The association of unadjusted long-term survival and adjusted survival with Cerebral Performance Category was calculated. Of the 2,417 patients who were identified to have undergone cardiac arrest, 24.1% (582/2,417) were successfully resuscitated, of whom 24.1% (140/582) received postarrest targeted temperature management. Overall, 42.9% of patients (60/140) were discharged with Cerebral Performance Category 1, 27.1% (38/140) with Cerebral Performance Category 2, 18.6% (26/140) with Cerebral Performance Category 3, and 11.4% (16/140) with Cerebral Performance Category 4. Cerebral Performance Category 1 survivors had the highest long-term survival followed by Cerebral Performance Categories 2 and 3, with Cerebral Performance Category 4 having the lowest long-term survival (p < 0.001, log-rank test). We found that Cerebral Performance Category 3 (hazard ratio = 3.62, p < 0.05) and Cerebral Performance Category 4 (hazard ratio = 12.73, p < 0.001) remained associated with worse survival after adjusting for age, gender, race, shockable rhythm, time to targeted temperature management initiation, total duration of resuscitation, withdrawal of care, and location of arrest. CONCLUSION: Patients with different Cerebral Performance Category scores at discharge have significantly different survival trajectories. Favorable Cerebral Performance Category at hospital discharge predicts better long-term outcomes of survivors of cardiac arrest who received targeted temperature management than those with less favorable Cerebral Performance Category scores.