Rearrest after prehospital resuscitation

A retrospective, multi-agency 'target trial emulation' for the comparison of post-resuscitation epinephrine to norepinephrine

INTRODUCTION

Epinephrine and norepinephrine are the two most commonly used prehospital vasopressors in the United States. Prior studies have suggested that use of a post-ROSC epinephrine infusion may be associated with increased rearrest and mortality in comparison to use of norepinephrine. We used target trial emulation methodology to compare the rates of rearrest and mortality between the groups of OHCA patients receiving these vasopressors in the prehospital setting.

METHODS

Adult (18-80 years of age) non-traumatic OHCA patients in the 2018-2022 ESO Data Collaborative datasets with a documented post-ROSC norepinephrine or epinephrine infusion were included in this study. Logistic regression modeling was used to evaluate the association between vasopressor agent and outcome using two sets of covariables. The first set of covariables included standard Utstein factors, the dispatch to ROSC interval, the ROSC to vasopressor interval, and the follow-up interval. The second set added prehospital systolic blood pressure and SpO2 values. Kaplan-Meier time-to-event analysis was also conducted and the vasopressor groups were compared using a multivariable Cox regression model.

RESULTS

Overall, 1,893 patients treated by 309 EMS agencies were eligible for analysis. 1,010 (53.4%) received an epinephrine infusion and 883 (46.7%) received a norepinephrine infusion as their initial vasopressor. Adjusted analyses did not discover an association between vasopressor agent and rearrest (aOR: 0.93 [0.72, 1.21]) or mortality (aOR: 1.00 [0.59, 1.69]).

CONCLUSIONS

In this multi-agency target trial emulation, the use of a post-resuscitation epinephrine infusion was not associated with increased odds of rearrest in comparison to the use of a norepinephrine infusion.

The association of clinical, treatment, and demographic characteristics with rearrest in a national dataset

INTRODUCTION

Following initial resuscitation from out-of-hospital cardiac arrest, rearrest frequently occurs and has been associated with adverse outcomes. We aimed to identify clinical, treatment, and demographic characteristics associated with prehospital rearrest at the encounter and agency levels.

METHODS

Adult non-traumatic cardiac arrest patients who achieved ROSC following EMS resuscitation in the 2018-2021 ESO annual datasets were included in this study. Patients were excluded if they had a documented DNR/POLST or achieved ROSC after bystander CPR only. Rearrest was defined as post-ROSC CPR initiation, administration of ≥ 1 milligram of adrenaline, defibrillation, or a documented non-perfusing rhythm on arrival at the receiving hospital. Multivariable logistic regression modeling was used to evaluate the association between rearrest and case characteristics. Linear regression modeling was used to evaluate the association between agency-level factors (ROSC rate, scene time, and scene termination rate), and rearrest rate.

RESULTS

Among the 53,027 cases included, 16,116 (30.4%) experienced rearrest. Factors including longer response intervals, longer 'low-flow' intervals, unwitnessed OHCA, and a lack of bystander CPR were associated with rearrest. Among agencies that treated ≥ 30 patients with outcome data, the agency-level rate of rearrest was inversely associated with agency-level rate of survival to discharge to home (R2 = -0.393, p < 0.001).

CONCLUSIONS

This multiagency retrospective study found that factors associated with increased ischaemic burden following OHCA were associated with rearrest. Agency-level rearrest frequency was inversely associated with agency-level survival to home. Interventions that decrease the burden of ischemia sustained by OHCA patients may decrease the rate of rearrest and increase survival.

A novel predictor of unsustained return of spontaneous circulation in cardiac arrest patients through a combination of capnography and pulse oximetry: a multicenter observational study

BACKGROUND

Unsustained return of spontaneous circulation (ROSC) is a critical barrier to survival in cardiac arrest patients. This study examined whether end-tidal carbon dioxide (ETCO2) and pulse oximetry photoplethysmogram (POP) parameters can be used to identify unsustained ROSC.

METHODS

We conducted a multicenter observational prospective cohort study of consecutive patients with cardiac arrest from 2013 to 2014. Patients' general information, ETCO2, and POP parameters were collected and statistically analyzed.

RESULTS

The included 105 ROSC episodes (from 80 cardiac arrest patients) comprised 51 sustained ROSC episodes and 54 unsustained ROSC episodes. The 24-hour survival rate was significantly higher in the sustained ROSC group than in the unsustained ROSC group (29.2% vs. 9.4%, P<0.05). The logistic regression analysis showed that the difference between after and before ROSC in ETCO2 (ΔETCO2) and the difference between after and before ROCS in area under the curve of POP (ΔAUCp) were independently associated with sustained ROSC (odds ratio [OR]=0.931, 95% confidence interval [95% CI] 0.881-0.984, P=0.011 and OR=0.998, 95% CI 0.997-0.999, P<0.001). The area under the receiver operating characteristic curve of ΔETCO2, ΔAUCp, and the combination of both to predict unsustained ROSC were 0.752 (95% CI 0.660-0.844), 0.883 (95% CI 0.818-0.948), and 0.902 (95% CI 0.842-0.962), respectively.

CONCLUSION

Patients with unsustained ROSC have a poor prognosis. The combination of ΔETCO2 and ΔAUCp showed significant predictive value for unsustained ROSC.

How to predict the death risk after an in-hospital cardiac arrest (IHCA) in intensive care unit? A retrospective double-centre cohort study from a tertiary hospital in China

OBJECTIVES

Our objective is to develop a prediction tool to predict the death after in-hospital cardiac arrest (IHCA).

DESIGN

We conducted a retrospective double-centre observational study of IHCA patients from January 2015 to December 2021. Data including prearrest diagnosis, clinical features of the IHCA and laboratory results after admission were collected and analysed. Logistic regression analysis was used for multivariate analyses to identify the risk factors for death. A nomogram was formulated and internally evaluated by the boot validation and the area under the curve (AUC). Performance of the nomogram was further accessed by Kaplan-Meier survival curves for patients who survived the initial IHCA.

SETTING

Intensive care unit, Tongji Hospital, China.

PARTICIPANTS

Adult patients (≥18 years) with IHCA after admission. Pregnant women, patients with 'do not resuscitation' order and patients treated with extracorporeal membrane oxygenation were excluded.

INTERVENTIONS

None.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was the death after IHCA.

RESULTS

Patients (n=561) were divided into two groups: non-sustained return of spontaneous circulation (ROSC) group (n=241) and sustained ROSC group (n=320). Significant differences were found in sex (p=0.006), cardiopulmonary resuscitation (CPR) duration (p<0.001), total duration of CPR (p=0.014), rearrest (p<0.001) and length of stay (p=0.004) between two groups. Multivariate analysis identified that rearrest, duration of CPR and length of stay were independently associated with death. The nomogram including these three factors was well validated using boot calibration plot and exhibited excellent discriminative ability (AUC 0.88, 95% CI 0.83 to 0.93). The tertiles of patients in sustained ROSC group stratified by anticipated probability of death revealed significantly different survival rate (p<0.001).

CONCLUSIONS

Our proposed nomogram based on these three factors is a simple, robust prediction model to accurately predict the death after IHCA.

The association of the post-resuscitation on-scene interval and patient outcomes after out-of-hospital cardiac arrest

BACKGROUND

After resuscitation from out-of-hospital cardiac arrest (OHCA) by Emergency Medical Services (EMS), the amount of time that should be dedicated to pre-transport stabilization is unclear. We examined whether the time spent on-scene after return of spontaneous circulation (ROSC) was associated with patient outcomes.

METHODS

We examined consecutive adult EMS-treated OHCAs from the British Columbia Cardiac Arrest registry (January 1/2019-June 1/2021) that had on-scene ROSC (sustained to scene departure). The primary outcome was favourable neurological outcome (Cerebral Performance Category ≤ 2) at hospital discharge; secondary outcomes were re-arrest during transport and hospital-discharge survival. Using adjusted logistic regression models, we estimated the association between the post-resuscitation on-scene interval (divided into quartiles) and outcomes.

RESULTS

Of 1653 cases, 611 (37%) survived to hospital discharge, and 523 (32%) had favourable neurological outcomes. The median post-resuscitation on-scene interval was 18.8 minutes (IQR:13.0-25.5). Compared to the first post-resuscitation on-scene interval quartile, neither the second (adjusted odds ratio [AOR] 1.19; 95% CI 0.72-1.98), third (AOR 1.10; 95% CI 0.67-1.81), nor fourth (AOR 1.54; 95% CI 0.93-2.56) quartiles were associated with favourable neurological outcomes; however, the fourth quartile was associated with a greater odds of hospital-discharge survival (AOR 1.73; 95% CI 1.05-2.85), and both the third (AOR 0.40; 95% CI 0.22-0.72) and fourth (AOR 0.44;95% CI 0.24-0.81) quartiles were associated with a lower odds of intra-transport re-arrest.

CONCLUSION

Among resuscitated OHCAs, increased post-resuscitation on-scene time was not associated with improved neurological outcomes, but was associated with improved survival to hospital discharge and decreased intra-transport re-arrest.

Association between a Post-Resuscitation Care Bundle and the Odds of Field Rearrest after Successful Resuscitation from Out-of-Hospital Cardiac Arrest: A Pre/Post Study

OBJECTIVES

Rearrest after successful resuscitation from out-of-hospital cardiac arrest (OHCA) is common and is associated with worse patient outcomes. However, little is known about the effect of interventions designed to prevent rearrest. We assessed the association between a prehospital care protocol for immediate management after return of spontaneous circulation (ROSC) and rates of field rearrest and survival to discharge in patients with prehospital ROSC.

METHODS

This was a retrospective study of adult patients with OHCA and field ROSC within a large EMS system before (April 2017-August 2018) and after (April 2019-February 2020) implementation of a structured prehospital post-ROSC care protocol. The protocol was introduced in September 2018 and provided on-scene stabilization direction including guidance on ventilation and blood pressure support. Field data and hospital outcomes were used to compare the frequency of field rearrest, hospital survival, and survival with good neurologic outcome before and after protocol implementation. Logistic regression was used to assess the association between the post-implementation period and these outcomes, and odds ratios were reported. The association between individual interventions on these outcomes was also explored.

RESULTS

There were 2,706 patients with ROSC after OHCA in the pre-implementation period and 1,780 patients in the post-implementation period. The rate of prehospital rearrest was 43% pre-implementation vs 45% post-implementation (RD 2%, 95% CI -1, 4%). In the adjusted analysis, introduction of the protocol was not associated with decreased odds of rearrest (OR 0.87, 95% CI 0.73, 1.04), survival to hospital discharge (OR 1.01, 95% CI 0.81, 1.24), or survival with good neurologic outcome (OR 0.81, 95% CI 0.61, 1.06). Post-implementation, post-ROSC administration of saline and push-dose epinephrine increased from 11% to 25% (RD 14%, 95% CI 11, 17%) and from 3% to 12% (RD 9% 95% CI 7, 11%), respectively. In an exploratory analysis, push-dose epinephrine was associated with a decreased odds of rearrest (OR 0.68, 95% CI 0.50, 0.94).

CONCLUSIONS

Introduction of a post-ROSC care protocol for patients with prehospital ROSC after OHCA was not associated with reduced odds of field rearrest. When elements of the care bundle were considered individually, push-dose epinephrine was associated with decreased odds of rearrest.

Automated aortic endovascular balloon volume titration prevents re-arrest immediately after return of spontaneous circulation in a swine model of nontraumatic cardiac arrest

Objectives

Endovascular aortic occlusion as an adjunct to cardiopulmonary resuscitation (CPR) for non-traumatic cardiac arrest is gaining interest. In a recent clinical trial, return of spontaneous circulation (ROSC) was achieved despite prolonged no-flow times. However, 66% of patients re-arrested upon balloon deflation. We aimed to determine if automated titration of endovascular balloon volume following ROSC can augment diastolic blood pressure (DBP) to prevent re-arrest.

Methods

Twenty swine were anesthetized and placed into ventricular fibrillation (VF). Following 7 minutes of no-flow VF and 5 minutes of mechanical CPR, animals were subjected to complete aortic occlusion to adjunct CPR. Upon ROSC, the balloon was either deflated steadily over 5 minutes (control) or underwent automated, dynamic adjustments to maintain a DBP of 60 mmHg (Endovascular Variable Aortic Control, EVAC).

Results

ROSC was obtained in ten animals (5 EVAC, 5 REBOA). Sixty percent (3/5) of control animals rearrested while none of the EVAC animals rearrested (p = 0.038). Animals in the EVAC group spent a significantly higher proportion of the post-ROSC period with a DBP > 60 mmHg [median (IQR)] [control 79.7 (72.5–86.0)%; EVAC 97.7 (90.8–99.7)%, p = 0.047]. The EVAC group had a statistically significant reduction in arterial lactate concentration [7.98 (7.4–8.16) mmol/L] compared to control [9.93 (8.86–10.45) mmol/L, p = 0.047]. There were no statistical differences between the two groups in the amount of adrenaline (epinephrine) required.

Conclusion

In our swine model of cardiac arrest, automated aortic endovascular balloon titration improved DBP and prevented re-arrest in the first 20 minutes after ROSC.

Rearrest during hospitalisation in adult comatose out-of-hospital cardiac arrest patients: Risk factors and prognostic impact, and predictors of favourable long-term outcomes

BACKGROUND

Rearrest occurs commonly after initial resuscitation following out-of-hospital cardiac arrest (OHCA). We determined (1) the predictors of rearrest during hospitalisation that can be identified in the hours immediately after OHCA, (2) the association between rearrest and favourable long-term outcomes, and (3) the predictors of favourable long-term outcomes in rearrest patients.

METHODS

Conditional multivariable logistic regression analyses were performed using the Korean Hypothermia Network prospective registry data, which included details of adult OHCA patients treated with targeted temperature management at 22 teaching hospitals in South Korea.

RESULTS

Among the 1,233 patients, 260 (21.1%) experienced rearrest. Of the 192 patients resuscitated from first rearrest, 33 (17.2%) achieved 6-month favourable outcomes. Arrhythmia, heart failure, ST-segment elevation, lower initial Glasgow coma scale (GCS) motor score, higher initial lactate level, and antiarrhythmic drug use within 1 h were independently associated with rearrest. Higher lactate level and antiarrhythmic drug use were associated with shockable first rearrest, while arrhythmia, heart failure, ST-segment elevation, and lower GCS motor score were associated with non-shockable first rearrest. Rearrest was independently associated with a lower likelihood of 6-month favourable outcomes (P = 0.003). Initial shockable rhythm after OHCA, absence of diabetes, shorter cumulative time to restoration of spontaneous circulation, coronary angiography, and hypophosphataemia within 7 d were independently associated with 6-month favourable outcomes in the patients resuscitated from first rearrest.

CONCLUSIONS

Rearrest during hospitalisation after OHCA was inversely associated with 6-month favourable outcomes. We identified several risk factors for rearrest and prognostic factors for patients resuscitated from first rearrest.

Can We Predict Good Survival Outcomes by Classifying Initial and Re-Arrest Rhythm Change Patterns in Out-of-Hospital Cardiac Arrest Settings?

Objective

The purpose of this study was to investigate whether a change in prehospital arrest rhythms could allow medical personnel to predict survival outcomes in patients who achieved a return of spontaneous circulation (ROSC) in the setting of out-of-hospital cardiac arrest (OHCA).

Methods

The design of this study was retrospective, multi-regional, observational, and cross-sectional with a determining period between August 2015 and July 2016. Cardiac arrest rhythms were defined as a shockable rhythm (S), which refers to ventricular fibrillation (VF) or pulseless ventricular tachycardia (pVT), and non-shockable rhythm (NS), which refers to pulseless electrical activity or asystole. Survival to admission, survival to discharge, and good cerebral performance category (CPC) (CPC 1 or 2) were defined as good survival outcomes.

Results

A total of 163 subjects were classified into four groups according to the rhythm change pattern: NS→NS (98), S→S (27), S→NS (23), and NS→S (15). NS→NS pattern was used as the reference in logistic regression analysis. In the case of survival to hospital admission, the odds ratio (OR) (95% CI) of the S→S pattern was the highest [12.63 (3.56-44.85), p: <0.001 by no correction] and [7.29 (1.96-27.10), p = 0.003 with adjusting]. In the case of survival to hospital discharge, the OR (95% CI) of the S→S pattern was the highest [37.14 (11.71-117.78), p: <0.001 by no correction] and [13.85 (3.69-51.97), p: <0.001 with adjusting]. In the case of good CPC (CPC 1 or 2) at discharge, the OR (95% CI) of the S→S pattern was the highest [96 (19.14-481.60), p: <0.001 by no correction] and [149.69 (19.51-1148.48), p: <0.001 with adjusting].

Conclusions

The S→S group showed the highest correlation with survival to hospital admission, survival to hospital discharge, and good CPC (CPC 1 or 2) at discharge compared to the NS→NS group. Verifying changes in initial cardiac arrest rhythm and prehospital re-arrest (RA) rhythm patterns after prehospital ROSC can help us predict good survival outcomes in the OHCA setting.

Towards the Prediction of Rearrest during Out-of-Hospital Cardiac Arrest

A secondary arrest is frequent in patients that recover spontaneous circulation after an out-of-hospital cardiac arrest (OHCA). Rearrest events are associated to worse patient outcomes, but little is known on the heart dynamics that lead to rearrest. The prediction of rearrest could help improve OHCA patient outcomes. The aim of this study was to develop a machine learning model to predict rearrest. A random forest classifier based on 21 heart rate variability (HRV) and electrocardiogram (ECG) features was designed. An analysis interval of 2 min after recovery of spontaneous circulation was used to compute the features. The model was trained and tested using a repeated cross-validation procedure, on a cohort of 162 OHCA patients (55 with rearrest). The median (interquartile range) sensitivity (rearrest) and specificity (no-rearrest) of the model were 67.3% (9.1%) and 67.3% (10.3%), respectively, with median areas under the receiver operating characteristics and the precision–recall curves of 0.69 and 0.53, respectively. This is the first machine learning model to predict rearrest, and would provide clinically valuable information to the clinician in an automated way.

Survival and Rearrest in out-of-Hospital Cardiac Arrest Patients with Prehospital Return of Spontaneous Circulation: A Prospective Multi-Regional Observational Study

OBJECTIVE

We aimed to determine the factors associated with rearrest after prehospital return of spontaneous circulation (ROSC) and examine the factors associated with survival despite rearrest.

METHODS

We conducted a prospective multi-regional observational study of out-of-hospital cardiac arrest (OHCA) patients between August 2015 and July 2016. Patients received prehospital advanced cardiovascular life support performed by emergency medical technicians (EMTs). EMTs were directly supervised by medical directors (physicians) via real-time smartphone video calls [Smart Advanced Life Support (SALS)]. The study participants were categorized into rearrest (+) and rearrest (-) groups depending on whether rearrest occurred after prehospital ROSC. After rearrest, patients were further classified as survivors or non-survivors at discharge.

RESULTS

SALS was performed in 1,711 OHCA patients. Prehospital ROSC occurred in 345 patients (20.2%); of these patients, 189 (54.8%) experienced rearrest [rearrest (+) group] and 156 did not experience rearrest [rearrest (-) group]. Multivariate analysis showed that a longer interval from collapse to first prehospital ROSC was independently associated with rearrest [odds ratio (OR) 1.081; 95% confidence interval (CI) 1.050-1.114]. The presence of an initial shockable rhythm was independently associated with survival after rearrest (OR 6.920; 95% CI 2.749-17.422). As a predictor of rearrest, the interval from collapse to first prehospital ROSC (cut-off: 24 min) had a sensitivity of 77% and a specificity of 54% (AUC = 0.715 [95% CI 0.661-0.769]).

CONCLUSIONS

A longer interval from collapse to first prehospital ROSC was associated with rearrest, and an initial shockable rhythm was associated with survival despite the occurrence of rearrest. Emergency medical service providers and physicians should be prepared to deal with rearrest when pulses are obtained late in the resuscitation.

Prehospital Epinephrine as a Potential Factor Associated with Prehospital Rearrest

Objective: To investigate the impact of epinephrine on prehospital rearrest and re-attainment of prehospital return of spontaneous circulation (ROSC). Methods: Data for 9,292 (≥ 8 years) out-of-hospital cardiac arrest (OHCA) patients transported to hospitals by emergency medical services were collected in Ishikawa Prefecture, Japan during 2010-2018. Univariate and multivariable analyses were retrospectively performed for 1,163 patients with prehospital ROSC. Results: Of 1,163 patients, rearrest occurred in 272 (23.4%) but not in 891 (76.6%). Both single and multiple doses of epinephrine administered before prehospital ROSC (adjusted odds ratio (OR): 3.62, 95% confidence interval (CI): 2.42-5.46 for 1 mg, and 4.27, 2.58-6.79 for ≥ 2 mg) were main factors associated with rearrest. The association between initial and rearrest rhythms was significantly associated with epinephrine administration (p = 0.02). However, the rearrest rhythm was primarily associated with the initial rhythm (p < 0.01). The majority of patients with the non-shockable initial rhythm had pulseless electrical activity (PEA) as the rearrest rhythm, regardless of epinephrine administration (80.4% for administration, 81.6% for no administration). When the initial rhythm was shockable, the primary rearrest rhythms in patients with and without epinephrine administration before prehospital ROSC were PEA (52.2%) and ventricular fibrillation/pulseless ventricular tachycardia (56.8%), respectively. Only epinephrine administration after rearrest was associated with prehospital re-attainment of ROSC (adjusted OR: 2.49, 95% CI: 1.20-5.19). Stepwise multivariable logistic regression analyses revealed that neurologically favorable outcome was poorer in patients with rearrest than those without rearrest (9.9% vs. 25.0%, adjusted OR: 0.42, 95% CI: 0.23-0.73). The total prehospital doses of epinephrine were associated with poorer neurological outcome in a dose-dependent manner (adjusted OR: 0.22, 95% CI: 0.13-0.36 for 1 mg; 0.09, 0.04-0.19 for 2 mg; 0.03, 0.01-0.09 for ≥ 3 mg, no epinephrine as a reference). Transportation to hospitals with a unit for post-resuscitation care was associated with better neurological outcome (adjusted OR: 1.53, 95% CI: 1.02-2.32). Conclusions: The requirement for epinephrine administration before prehospital ROSC was associated with subsequent rearrest. Routine epinephrine administrations and rearrest were associated with poorer neurological outcome of OHCA patients with prehospital ROSC.

Prognostic Factors for Re-Arrest with Shockable Rhythm during Target Temperature Management in Out-Of-Hospital Shockable Cardiac Arrest Patients

Re-arrest during post-cardiac arrest care after the return of spontaneous circulation is not uncommon. However, little is known about the risk factors associated with re-arrest. A previous study failed to show a benefit of prophylactic antiarrhythmic drug infusion in all kinds of out-of-hospital cardiac arrest (OHCA) survivors. This study evaluated high-risk OHCA survivors who may have re-arrest with shockable rhythm during targeted temperature management (TTM). Medical records of consecutive OHCA survivors treated with TTM at four tertiary referral university hospitals in the Republic of Korea between January 2010 and December 2016 were retrospectively reviewed. Patients who did not have any shockable rhythm during cardiopulmonary resuscitation (CPR) or unknown initial rhythm were excluded. The primary outcome of interest was the recurrence of shockable cardiac arrest during TTM. There were 289 cases of initial shockable arrest rhythm and 132 cases of shockable rhythm during CPR. Of the 421 included patients, 11.4% of patients had a shockable re-arrest during TTM. Survival to discharge and good neurologic outcomes did not differ between non-shockable and shockable re-arrest patients (78.3% vs. 72.9%, p = 0.401; 53.1% vs. 54.2% p = 0.887). Initial serum magnesium level, ST segment depression or ventricular premature complex (VPC) in initial electrocardiography (ECG), prophylactic amiodarone infusion, and dopamine and norepinephrine infusion during TTM were significantly higher and more frequent in the shockable re-arrest group (all p values < 0.05). Normal ST and T wave in initial ECG was common in the non-shockable re-arrest group (p = 0.038). However, in multivariate logistic regression analysis, only VPC was an independent prognostic factor for shockable re-arrest (OR 2.806 (95% CI 1.276-6.171), p = 0.010). Initial VPC may be a prognostic risk factor for shockable re-arrest in OHCA survivors with shockable rhythm.

The effect of extracorporeal cardiopulmonary resuscitation in re-arrest after survival event: a retrospective analysis

BACKGROUND

The objectives of this study were to 1) identify the risk factors for predicting re-arrest and 2) determine whether extracorporeal cardiopulmonary resuscitation results in better outcomes than conventional cardiopulmonary resuscitation for managing re-arrest in out-of-hospital cardiac arrest patients.

METHODS

This retrospective analysis was based on a prospective cohort. We included adult patients with non-traumatic out-of-hospital cardiac arrest who achieved a survival event. The primary measurement was re-arrest, defined as recurrent cardiac arrest within 24 hours after survival event. Multiple logistic regression analysis was used to predict re-arrest. Subgroup analysis was performed to evaluate the effect of extracorporeal cardiopulmonary resuscitation on the survival to discharge in out-of-hospital cardiac arrest patients who experienced re-arrest.

RESULTS

Of 534 patients suitable for inclusion, 203 (38.0%) were enrolled in the re-arrest group. Old age, prolonged advanced cardiac life support duration and the presence of hypotension at 0 hours after survival event were independent variables predicting re-arrest. In the re-arrest group, the extracorporeal cardiopulmonary resuscitation group (n = 25) showed better outcomes than the conventional cardiopulmonary resuscitation group. However, multiple logistic regression for predicting survival to discharge revealed that extracorporeal cardiopulmonary resuscitation was not an independent factor. Multiple logistic regression revealed that a hypotensive state at re-arrest was an independent risk factor for survival.

CONCLUSION

Alternative methods that reduce the advanced cardiac life support duration should be considered to prevent re-arrest and attain good outcomes in out-of-hospital cardiac arrest patients. Extracorporeal cardiopulmonary resuscitation for re-arrest tended to show a good outcome compared to conventional cardiopulmonary resuscitation for re-arrest. Avoiding or immediately correcting hypotension may prevent re-arrest and improve the outcome of re-arrested patients.

Death after awakening from post-anoxic coma: the "Best CPC" project

BACKGROUND

In patients who recover consciousness after cardiac arrest (CA), a subsequent death from non-neurological causes may confound the assessment of long-term neurological outcome. We investigated the prevalence and causes of death after awakening (DAA) in a multicenter cohort of CA patients.

METHODS

Observational multicenter cohort study on patients resuscitated from CA in eight European intensive care units (ICUs) from January 2007 to December 2014. DAA during the hospital stay was extracted retrospectively from patient medical records. Demographics, comorbidities, initial CA characteristics, concomitant therapies, prognostic tests (clinical examination, electroencephalography (EEG), somatosensory evoked potentials (SSEPs)), and cause of death were identified.

RESULTS

From a total 4646 CA patients, 2478 (53%) died in-hospital, of whom 196 (4.2%; ranges 0.6-13.0%) had DAA. DAA was less frequent among out-of-hospital than in-hospital CA (82/2997 [2.7%] vs. 114/1649 [6.9%]; p < 0.001). Median times from CA to awakening and from awakening to death were 2 [1-5] and 9 [3-18] days, respectively. The main causes of DAA were multiple organ failure (n = 61), cardiogenic shock (n = 61), and re-arrest (n = 26). At day 3 from admission, results from EEG (n = 56) and SSEPs (n = 60) did not indicate poor outcome.

CONCLUSIONS

In this large multicenter cohort, DAA was observed in 4.2% of non-survivors. Information on DAA is crucial since it may influence epidemiology and the design of future CA studies evaluating neuroprognostication and neuroprotection.

Effects of intra-resuscitation antiarrhythmic administration on rearrest occurrence and intra-resuscitation ECG characteristics in the ROC ALPS trial

BACKGROUND

Intra-resuscitation antiarrhythmic drugs may improve resuscitation outcomes, in part by avoiding rearrest, a condition associated with poor out-of-hospital cardiac arrest (OHCA) outcomes. However, antiarrhythmics may also alter defibrillation threshold. The objective of this study was to investigate the relationship between rearrest and intra-resuscitation antiarrhythmic drugs in the context of the Resuscitation Outcomes Consortium (ROC) amiodarone, lidocaine, and placebo (ALPS) trial.

HYPOTHESIS

Rearrest rates would be lower in cases treated with amiodarone or lidocaine, versus saline placebo, prior to first return of spontaneous circulation (ROSC). We also hypothesized antiarrhythmic effects would be quantifiable through analysis of the prehospital electrocardiogram.

METHODS

We conducted a secondary analysis of the ROC ALPS trial. Cases that first achieved prehospital ROSC after randomized administration of study drug were included in the analysis. Rearrest, defined as loss of pulses following ROSC, was ascertained from emergency medical services records. Rearrest rate was calculated overall, as well as by ALPS treatment group. Multivariable logistic regression models were constructed to assess the association between treatment group and rearrest, as well as rearrest and both survival to hospital discharge and survival with neurologic function. Amplitude spectrum area, median slope, and centroid frequency of the ventricular fibrillation (VF) ECG were calculated and compared across treatment groups.

RESULTS

A total of 1144 (40.4%) cases with study drug prior to first ROSC were included. Rearrest rate was 44.0% overall; 42.9% for placebo, 45.7% for lidocaine, and 43.0% for amiodarone. In multivariable logistic regression models, ALPS treatment group was not associated with rearrest, though rearrest was associated with poor survival and neurologic outcomes. AMSA and median slope measures of the first available VF were associated with rearrest case status, while median slope and centroid frequency were associated with ALPS treatment group.

CONCLUSION

Rearrest rates did not differ between antiarrhythmic and placebo treatment groups. ECG waveform characteristics were correlated with treatment group and rearrest. Rearrest was inversely associated with survival and neurologic outcomes.

Compression-to-ventilation ratio and incidence of rearrest-A secondary analysis of the ROC CCC trial

BACKGROUND

Previous work has demonstrated that when out-of-hospital cardiac arrest (OHCA) patients achieve return of spontaneous circulation (ROSC), but subsequently have another cardiac arrest prior to hospital arrival (rearrest), the probability of survival to hospital discharge is significantly decreased. Additionally, few modifiable factors for rearrest are known. We sought to examine the association between rearrest and compression-to-ventilation ratio during cardiopulmonary resuscitation (CPR) and to confirm the association between rearrest and outcomes.

HYPOTHESIS

Rearrest incidence would be similar between cases treated with 30:2 or continuous chest compression (CCC) CPR, but inversely related to survival and good neurological outcome.

METHODS

We conducted a secondary analysis of a large randomized-controlled trial of CCC versus 30:2 CPR for the treatment of OHCA between 2011 and 2015 among 8 sites of the Resuscitation OUTCOMES: Consortium (ROC). Patients were randomized through an emergency medical services (EMS) agency-level cluster randomization design to receive either 30:2 or CCC CPR. Case data were derived from prehospital patient care reports, digital defibrillator files, and hospital records. The primary analysis was an as-treated comparison of the proportion of patients with a rearrest for patients who received 30:2 versus those who received CCC. In addition, we assessed the association between rearrest and both survival to hospital discharge and favorable neurological outcome (Modified Rankin Score≤3) in patients with and without ROSC upon ED arrival using multivariable logistic regression adjusting for age, sex, initial rhythm and measures of CPR quality.

RESULTS

There were 14,109 analyzable cases that were determined to have definitively received either CCC or 30:2 CPR. Of these, 4713 had prehospital ROSC and 2040 (43.2%) had at least one rearrest. Incidence of rearrest was not significantly different between patients receiving CCC and 30:2 (44.1% vs 41.8%; adjusted OR: 1.01; 95% CI: 0.88, 1.16). Rearrest was significantly associated with lower survival (23.3% vs 36.9%; adjusted OR: 0.46; 95%CI: 0.36-0.51) and worse neurological outcome (19.4% vs 30.2%; adjusted OR: 0.46; 95%CI: 0.38, 0.55).

CONCLUSION

Rearrest occurrence was not significantly different between patients receiving CCC and 30:2, and was inversely associated with survival to hospital discharge and MRS.

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.

Perishock Pause Intervals and Rearrest after Out-of-Hospital Cardiac Arrest

BACKGROUND

The loss of pulses after successful return of spontaneous circulation (ROSC) in out-of-hospital cardiac arrest (OHCA) is known as rearrest (RA). The causes of RA are not well understood.

OBJECTIVES

To investigate the association between shock pause intervals and RA.

METHODS

Data from treated OHCA with ROSC and one or more defibrillation attempts were obtained from one site of the Resuscitation Outcomes Consortium. All analyses were conducted internally. Data available for analysis included cases spanning 2006-2008 and 2010-2011. Defibrillator tracings were used to calculate both components of the perishock pause (PSP) interval: the pre- (preSP) and the postshock pauses (postSP). RA and no-RA shock pauses were compared and independent associations between shock pause intervals, patient characteristics, and RA were assessed with the appropriate statistical tests.

RESULTS

Analysis included 241 shocks from 101 cases. Forty-one cases (41%) had RA. RA vs. no-RA median (interquartile range) shock pauses in seconds were: preSP 13.5 (6.0-18.0) vs. 15.0 (10.9-21.5) (p = 0.121); postSP 6.0 (3.5-8.2) vs. 8.7 (4.5-13.9) (p = 0.053); and PSP 18.0 (12.3-24.0) vs. 24.0 (16.7-30.2) (p = 0.022). Considering all possible shock pause durations, shock pause lengths and various patient characteristics were not associated with RA. If 30 s or shorter, the preSP (odds ratio [OR] 0.90, 955 confidence interval [CI] 0.82-0.98) and postSP (OR 0.89, 95% CI 0.79-0.99) were related to RA.

CONCLUSION

Shock pause length was inversely associated with RA when shock pause intervals were limited to 30 s or less. Shock pauses and RA were not associated when all durations of shock pauses were considered.

Incidence and outcomes of rearrest following out-of-hospital cardiac arrest

INTRODUCTION

Rearrest occurs when a patient experiences cardiac arrest after successful resuscitation. The incidence and outcomes of rearrest following out-of-hospital cardiac arrest have been estimated in limited local studies. We sought provide a large-scale estimate of rearrest incidence and its effect on survival.

METHODS

We obtained case data from emergency medical services-treated, out-of-hospital cardiac arrest from the Resuscitation Outcomes Consortium, a multi-site clinical research network with clinical centers in 11 regions in the US and Canada. The cohort comprised all cases captured between 2006 and 2008 at 10 of 11 regions with prehospital return of spontaneous circulation. We used three methods to ascertain rearrest via direct signal analysis, indirect signal analysis, and emergency department arrival vital status. Rearrest incidence was estimated as the proportion of cases with return of spontaneous circulation that experience rearrest. Regional rearrest incidence estimates were compared with the χ(2)-squared test. Multivariable logistic regression was used to assess the relationship between rearrest and survival to hospital discharge.

RESULTS

Out of 18,937 emergency medical services-assessed cases captured between 2006 and 2008, 11,456 (60.5%) cases were treated by emergency medical services and 4396 (38.4%) had prehospital return of spontaneous circulation. Of these, rearrest ascertainment data was available in 3253 cases, with 568 (17.5%) experiencing rearrest. Rearrest differed by region (10.2% to 21.2%, p < 0.001). Rearrest was inversely associated with survival (OR: 0.19, 95% CI: 0.14-0.26).

CONCLUSIONS

Rearrest was found to occur frequently after resuscitation and was inversely related to survival.

Inaccuracy of patient care reports for identification of critical resuscitation events during out-of-hospital cardiac arrest

OBJECTIVE

Out-of-hospital cardiac arrest (OHCA) is a leading cause of mortality in the United States. We sought to evaluate the accuracy of the patient care report (PCR) for detection of 2 clinically important events: return of spontaneous circulation (ROSC) and rearrest (RA).

METHODS

We used defibrillator recordings and PCRs for Emergency Medical Services-treated OHCA collected by the Resuscitation Outcomes Consortium's Pittsburgh site from 2006 to 2008 and 2011 to 2012. Defibrillator data included electrocardiogram rhythm tracing, chest compression measurement, and audio voice recording. Sensitivity analysis was performed by comparing the accuracy of the PCR to detect the presence and number of ROSC and RA events to integrated defibrillator data.

RESULTS

In the 158 OHCA cases, there were 163 ROSC events and 53 RA events. The sensitivity of PCRs to identify all ROSC events was 85% (confidence interval [CI], .795-.905); to identify primary ROSC events, it was 85% (CI, .793-.907); and to identify secondary ROSC events, it was 78% (CI, .565-.995). The sensitivity of PCRs to identify the presence of all RA events was .60 (CI, .469-.731); to identify primary RA events, it was 71% (CI, .578-.842); and to identify secondary RA events, it was 0. Of the 32 RA incidents captured by the PCR, only 15 (47%) correctly identified the correct lethal arrhythmia.

CONCLUSIONS

We found that PCRs are not a reliable source of information for assessing the presence of ROSC and post-RA electrocardiogram rhythm. For quality control and research purposes, medical providers should consider augmenting data collection with continuous defibrillator recordings before making any conclusions about the occurrence of critical resuscitation events.

Potential utility of near-infrared spectroscopy in out-of-hospital cardiac arrest: an illustrative case series

OBJECTIVE

We evaluated the measurement of tissue oxygen content (StO(2)) by continuous near-infrared spectroscopy (NIRS) during and following cardiopulmonary resuscitation (CPR) and compared the changes in StO(2) and end-tidal carbon dioxide (ETCO(2)) as a measure of return of spontaneous circulation (ROSC) or rearrest.

METHODS

This was a case series of five patients who experienced out-of hospital cardiac arrest. Patients included those who had already experienced ROSC, who were being transported to the hospital, or who were likely to have a reasonable amount of time remaining in the resuscitation efforts. Patients were continuously monitored from the scene using continuous ETCO(2) monitoring and a NIRS StO(2) monitor until they reached the hospital. The ETCO(2) and StO(2) values were continuously recorded and analyzed for comparison of the time points when patients were clinically identified to have ROSC or rearrest.

RESULTS

Four of five patients had StO(2) and EtCO(2) recorded during an episode of CPR and all were monitored during the postarrest period. Three patients experienced rearrest en route to the hospital. Downward trends were noted in StO(2) prior to each rearrest, and rapid increases were noted after ROSC. The StO(2) data showed less variance than the ETCO(2) data in the periarrest period.

CONCLUSIONS

This preliminary study in humans demonstrates that StO(2) dynamically changes during periods of hemodynamic instability in postarrest patients. These data suggest that a decline in StO(2) level may correlate with rearrest and may be useful as a tool to predict rearrest in post-cardiac arrest patients. A rapid increase in StO(2) was also seen upon ROSC and may be a better method of identifying ROSC during CPR than pauses for pulse checks or ETCO(2) monitoring.