Survival in out-of-hospital cardiac arrests with initial asystole or pulseless electrical activity and subsequent shockable rhythms

Background

Non-shockable arrest rhythms (pulseless electrical activity and asystole) represent an increasing proportion of reported cases of out-of-hospital cardiac arrest (OHCA). The prognostic significance of conversion from non-shockable to shockable rhythms during the course of resuscitation remains unclear.

Objective

To evaluate whether out-of-hospital cardiac arrest survival with initially non-shockable arrest rhythms is improved with subsequent conversion to shockable rhythms.

Methods

Secondary analysis of data in Epistry – Cardiac Arrest, an epidemiologic registry maintained by the Resuscitation Outcomes Consortium (ROC). This analysis includes OHCA events from December 1, 2005 through May 31, 2007 contributed by six US and two Canadian sites. For all EMS-treated adult (18 and older) cardiac arrest patients who presented with non-shockable cardiac arrest, we compared survival to hospital discharge between patients who did develop a shockable rhythm and those who did not based on receipt of subsequent defibrillation. Missing data were handled using multiple imputation. Multivariable logistic regression was used to adjust for potentially confounding variables.

Results

A total of 6556 EMS treated adult cardiac arrest cases presented in non-shockable rhythms. Survival to discharge in patients who converted to a shockable rhythm was 2.77% while survival in those who did not was 2.72% (p = 0.92). After adjusting for confounders, conversion to a shockable rhythm was not associated with improved survival (OR 0.88, 95% CI: 0.60–1.30).

Conclusion

For OHCA patients presenting in PEA/asystole, survival to hospital discharge was not associated with conversion to a shockable rhythm during EMS resuscitation efforts.     

Use of automated external defibrillators in patients with traumatic out-of-hospital cardiac arrest

Background

Because out-of-hospital cardiac arrests (OHCAs) due to a major trauma rarely present with shockable rhythms, the potential benefits of using automated external defibrillators (AEDs) at the scene of traumatic OHCAs have not been examined.

Methods

We conducted an observational, retrospective cohort study using an Utstein-style analysis in Tainan city, Taiwan. The enrollees were adult patients with traumatic OHCAs accessed by emergency medical technicians (EMTs) from January 1, 2004 to December 31, 2010. The exposure was the use or non-use of AEDs at the scene, as determined by the clinical judgment of the EMTs. The primary outcome evaluated was a sustained (≥2 h) return of spontaneous circulation (ROSC), and the secondary outcomes were prehospital ROSC, overall ROSC, survival to hospital admission, survival at one month and favorable neurologic status at one month.

Results

A total of 424 patients (313 males) were enrolled, of whom 280 had AEDs applied, and 144 did not. Only 25 (5.9%) patients had received bystander cardiopulmonary resuscitation (CPR), and merely 21 (7.5%) patients in the AED group presented with shockable rhythms. Compared to the non-AED group, the primary and secondary outcomes of the AED group were not significantly different, except for a significantly lower prehospital ROSC rate (1.1% vs 4.9%, p < 0.05). Multivariate analysis showed no significant interactions between the use of AEDs and other key variables. Use of the AED was not associated with sustained ROSC (OR 1.33; 95% CI 0.75–2.38, p = 0.33).

Conclusions

In a community with a low prevalence of shockable rhythms and administration of bystander CPR in patients with traumatic OHCA, we found no significant differences in the sustained ROSC between the AED and the non-AED groups. Considering scene safety and the possible interruption of CPR, we do not encourage the routine use of AEDs at the scene of traumatic OHCAs.     

C-reactive protein levels after cardiac arrest in patients treated with therapeutic hypothermia

Aim

Prognostication of outcome after cardiac arrest (CA) is challenging. We assessed the prognostic value of daily blood levels of C-reactive protein (CRP), a cheap and widely available inflammatory biomarker, after CA.

Methods

We reviewed the data of all patients admitted to our intensive care unit (ICU) after CA between January 2009 and December 2011 and who survived for at least 24 h. We collected demographic data, CA characteristics (initial rhythm; location of arrest; time to return of spontaneous circulation [ROSC]), occurrence of infection, ICU survival and neurological outcome at three months (good = cerebral performance category [CPC] 1–2; poor = CPC 3–5). CRP levels were measured daily from admission to day 3.

Results

A total of 130 patients were admitted after successful resuscitation from CA and survived more than 24 h; 76 patients (58%) developed an infection and overall mortality was 56%. CRP levels increased from admission to day 3. CRP levels were higher in in-hospital than in out-of-hospital CA, especially on admission and day 1 (44.1 vs. 2.1 mg L⁻¹ and 74.5 vs. 29.5 mg L⁻¹, respectively; p < 0.001), and in patients with non-shockable than in those with shockable rhythms. In a logistic regression model, high CRP levels on admission were independently associated with poor neurological outcome at 3 months.

Conclusion

CRP levels increase in the days following successful resuscitation of CA. Higher CRP levels in patients with in-hospital CA, non-shockable rhythms and infection, suggest a greater inflammatory response in these patients. High CRP levels on admission may identify patients at high-risk of poor outcome and could be a target for future therapies.     

A pilot study examining the role of regional cerebral oxygen saturation monitoring as a marker of return of spontaneous circulation in shockable (VF/VT) and non-shockable (PEA/Asystole) causes of cardiac arrest

Background

Non-invasive monitoring of cerebral perfusion and oxygen delivery during cardiac arrest is not routinely utilized during cardiac arrest resuscitation. The objective of this study was to investigate the feasibility of using cerebral oximetry during cardiac arrest and to determine the relationship between regional cerebral oxygen saturation (rSO2) with return of spontaneous circulation (ROSC) in shockable (VF/VT) and non-shockable (PEA/asystole) types of cardiac arrest.

Methods

Cerebral oximetry was applied to 50 in-hospital and out-of-hospital cardiac arrest patients.

Results

Overall, 52% (n = 26) achieved ROSC and 48% (n = 24) did not achieve ROSC. There was a significant difference in mean ± SD rSO2% in patients who achieved ROSC compared to those who did not (47.2 ± 10.7% vs. 31.7 ± 12.8%, p < 0.0001). This difference was observed during asystole (median rSO2 (IQR) ROSC versus no ROSC: 45.0% (35.1–48.8) vs. 24.9% (20.5–32.9), p < 0.002) and PEA (50.6% (46.7–57.5) vs. 31.6% (18.8–43.3), p = 0.02), but not in the VF/VT subgroup (43.7% (41.1–54.7) vs. 42.8% (34.9–45.0), p = 0.63). Furthermore, it was noted that no subjects with a mean rSO2 < 30% achieved ROSC.

Conclusions

Cerebral oximetry may have a role as a real-time, non-invasive predictor of ROSC during cardiac arrest. The main utility of rSO2 in determining ROSC appears to apply to asystole and PEA subgroups of cardiac arrest, rather than VF/VT. This observation may reflect the different physiological factors involved in recovery from PEA/asytole compared to VF/VT. Whereas in VF/VT, successful defibrillation is of prime importance, however in PEA and asytole achieving ROSC is more likely to be related to the quality of oxygen delivery. Furthermore, a persistently low rSO2 <30% in spite of optimal resuscitation methods may indicate futility of resuscitation efforts.     

Cardiac arrest due to drowning—Changes over time and factors of importance for survival

Aim

To evaluate changes in characteristics and survival over time in out-of-hospital cardiac arrest (OHCA) due to drowning and describe factors of importance for survival.

Method

Retrospectively reported and treated drowning cases reported to the Swedish OHCA registry between 1990 and 2012, n = 529. The data were clustered into three seven-year intervals for comparisons of changes over time.

Results

There were no changes in age, gender, witnessed status, shockable rhythm or place of OHCA during the time periods. Bystander CPR increased over time, 59% in interval 1992–1998, versus 74% in interval 2006–2012 (p = 0.005). There was a decrease in delay between OHCA and calling for the Emergency Medical Service (EMS) over the years, while calling for the EMS to arrival increased in terms of time. Survival to hospital admission appears to have increased over the years (p = 0.009), whereas survival to one month did not change significantly over time. In a multivariate analysis, witnessed status, female gender, bystander CPR, place–home and EMS response time were associated with survival to hospital admission. For survival to one month, place, age, shockable rhythm and logarithmised delay from calling for an ambulance to arrival were of significance for survival.

Conclusion

In OHCA due to drowning, over a period of 20 years, bystanders have called for help at an earlier stage and administered CPR more frequently in the past few years. Survival to hospital admission has increased, while shockable rhythm and early arrival of the EMS appear to be the most important factors for survival to one month.     

Prophylactic lidocaine for post resuscitation care of patients with out-of-hospital ventricular fibrillation cardiac arrest

Background

Antiarrhythmic drugs like lidocaine are usually given to promote return of spontaneous circulation (ROSC) during ongoing out-of-hospital cardiac arrest (OHCA) from ventricular fibrillation/tachycardia (VF/VT). Whether administering such drugs prophylactically for post-resuscitation care after ROSC prevents re-arrest and improves outcome is unstudied.

Methods

We evaluated a cohort of 1721 patients with witnessed VF/VT OHCA who did (1296) or did not receive prophylactic lidocaine (425) at first ROSC. Study endpoints included re-arrest, hospital admission and survival.

Results

Prophylacic lidocaine recipients and non-recipients were comparable, except for shorter time to first ROSC and higher systolic blood pressure at ROSC in those receiving lidocaine. After initial ROSC, arrest from VF/VT recurred in 16.7% and from non-shockable arrhythmias in 3.2% of prophylactic lidocaine recipients, 93.5% of whom were admitted to hospital and 62.4% discharged alive, as compared with 37.4%, 7.8%, 84.9% and 44.5%, of corresponding non-recipients (all p < 0.0001). Adjusted for pertinent covariates, prophylactic lidocaine was independently associated with reduced odds of re-arrest from VF/VT, odds ratio, (95% confidence interval) 0.34 (0.26–0.44) and from nonshockable arrhythmias (0.47 (0.29–0.78)); a higher hospital admission rate (1.88, (1.28–2.76)) and improved survival to discharge (1.49 (1.15–1.95)). However in a propensity score-matched sensitivity analysis, lidocaine's only beneficial association with outcome was in a lower incidence of recurrent VF/VT arrest.

Conclusions

Administration of prophylactic lidocaine upon ROSC after OHCA was consistently associated with less recurrent VF/VT arrest, and therapeutic equipoise for other measures. The prospect of a promising association between lidocaine prophylaxis and outcome, without evidence of harm, warrants further investigation.     

Factors associated with sustained return of spontaneous circulation in children after out-of-hospital cardiac arrest of noncardiac origin

Purpose

The study aimed to determine the factors predictive of sustained return of spontaneous circulation (ROSC) in children with out-of-hospital cardiac arrest (OHCA) of noncardiac origin.

Methods

Eighty children were included in this retrospective study. The variables that lead to sustained ROSC and those that do not lead to sustained ROSC were analyzed. Survival analyses, including chance of achieving sustained ROSC and sum duration of ROSC, were conducted according to the duration of in-hospital cardiopulmonary resuscitation (CPR).

Results

Etiologies of noncardiac OHCA differed significantly across different age groups (P < .001). Only 8.8% of children had initial arrest rhythms that were shockable. Predictors of sustained ROSC included the initial cardiac rhythm (P = .002), a shorter period between collapse and the first chest compression (P = .002), a shorter in-hospital CPR duration (P = .004), and prehospital CPR (P = .007). In children where ROSC was initially sustained, those with in-hospital CPR of more than 20 minutes, ROSC was sustained for less time (P < .001).

Conclusions

Few children with noncardiac OHCA present with shockable cardiac rhythms. Furthermore, long-term ROSC is difficult to maintain in children who receive in-hospital CPR for more than 20 minutes.     

Outcomes following out-of-hospital cardiac arrest with an initial cardiac rhythm of asystole or pulseless electrical activity in Victoria,Australia

Background

While internationally reported survival from out-of-hospital cardiac arrest (OHCA) is improving, much of the increase is being observed in patients presenting to emergency medical services (EMS) in shockable rhythms. The purpose of this study was to assess survival and 12-month functional recovery in patients presenting to EMS in asystole or pulseless electrical activity (PEA).

Methods

The Victorian Ambulance Cardiac Arrest Registry was searched for adult OHCA patients presenting in non-shockable rhythms in Victoria, Australia between 1st July 2003 and 30th June 2013. We excluded patients defibrillated prior to EMS arrival and arrests witnessed by EMS. Twelve-month quality-of-life interviews were conducted on survivors who arrested between 1st January 2010 and 31st December 2012. The main outcome measures were survival to hospital discharge and 12-month functional recovery measured by the Extended Glasgow Outcome Scale (GOSE).

Results

A total of 38,378 non-shockable OHCA attended by EMS were included, of which 88.0% were asystole and 11.6% were PEA. Of the patients receiving resuscitation, survival to hospital discharge was 1.1% for asystole and 5.9% for PEA (p < 0.001), with no significant improvement observed over the 10 year study period. In survivors with 12-month follow-up data, the combined rate of death, vegetative state or lower severe disability was 66.7% (95% CI 41.0–80.0%) for asystole and 44.7% (95% CI 30.2–59.9%) for PEA.

Conclusion

Survival outcomes following OHCA with initial rhythms of asystole or PEA did not improve over the 10-year study period. Our findings indicate high rates of death within 12 months, and unfavourable functional recovery for survivors.     

The impact of severe acidemia on neurologic outcome of cardiac arrest survivors undergoing therapeutic hypothermia

Introduction

Therapeutic Hypothermia (TH) has become a standard of care in improving neurological outcomes in cardiac arrest (CA) survivors. Previous studies have defined severe acidemia as plasma pH < 7.20. We investigated the influence of severe acidemia at the time of initiation of TH on neurological outcome in CA survivors.

Methods

A retrospective analysis was performed on 196 consecutive CA survivors (out-of-hospital CA and in-hospital CA) who underwent TH with endovascular cooling between January 2007 and October 2012. Arterial blood gas drawn prior to initiation of TH was utilized to measure pH in all patients. Shockable and non-shockable CA patients were divided into two sub-groups based on pH (pH < 7.2 and pH ≥ 7.2). The primary end-point was measured using the Pittsburgh Cerebral Performance Category (CPC) scale prior to discharge from the hospital: good (CPC 1 and 2) and poor (CPC 3 to 5) neurologic outcome.

Results

Sixty-two percent of shockable CA patients with pH ≥ 7.20 had good neurological outcome as compared to 34% patients with pH < 7.20. Shockable CA patients with pH ≥ 7.20 were 3.3 times more likely to have better neurological outcome when compared to those with pH <7.20 [p = 0.013, OR 3.3, 95% CI (1.28–8.45)]. In comparison, non-shockable CA patients with p ≥ 7.20 did not have a significantly different neurological outcome as compared to those with pH < 7.20 [p = 0.97, OR 1.02, 95% CI (0.31–3.3)].

Conclusion

Presence of severe acidemia at initiation of TH in shockable CA survivors is significantly associated with poor neurological outcomes. This effect was not observed in the non-shockable CA survivors.     

A randomized trial of compression first or analyze first strategies in patients with out-of-hospital cardiac arrest: results from an Asian community

Background

It is still under debate whether a period of cardiopulmonary resuscitation should be performed prior to rhythm analysis for defibrillation for out of hospital cardiac arrests (OHCA). This study compared outcomes of OHCA treated by “compression first” (CF) versus “analyze first” (AF) strategies in an Asian community with low rates of shockable rhythms.

Methods

This randomized trial was conducted in Taipei City between February 2008 and December 2009. Dispatches of suspected OHCA that activated advanced life support teams were randomized into the CF and AF strategies. Patients assigned to CF strategy received 10 cycles of CPR prior to analysis by automatic external defibrillator. The primary outcome was sustained (>2 h) return of spontaneous circulation (ROSC) and secondary outcome was survival to hospital discharge.

Results

We included 289 cases in the final analysis after exclusion by pre-specified criteria, 141 were allocated to CF strategy and 148 to AF strategy. Baseline characteristics were similar. Thirty-seven (26.2%) of those receiving CF strategy and 49 (33.1%) of the AF strategy achieved sustained ROSC (p = 0.25). In a post-hoc analysis of patients who achieved ROSC, those that received CF strategy were more likely to be discharged alive from the hospital (16/37 = 43.2% vs. 11/49 = 22.4%, p = 0.02).

Conclusion

In this study population of low rates of shockable rhythms, there was no difference in ROSC for CF or AF strategies. Considering the EMS operation situations, a period of paramedic-administered CPR for up to 10 cycles prior to rhythm analysis could be a feasible strategy in this community.     

Erythropoietin facilitates the return of spontaneous circulation and survival in victims of out-of-hospital cardiac arrest

Background

Erythropoietin activates potent protective mechanisms in non-hematopoietic tissues including the myocardium. In a rat model of ventricular fibrillation, erythropoietin preserved myocardial compliance enabling hemodynamically more effective CPR.

Objective

To investigate whether intravenous erythropoietin given within 2 min of physician-led CPR improves outcome from out-of-hospital cardiac arrest.

Methods

Erythropoietin (90,000 IU of beta-epoetin, n = 24) was compared prospectively with 0.9% NaCl (concurrent controls = 30) and retrospectively with a preceding group treated with similar protocol (matched controls = 48).

Results

Compared with concurrent controls, the erythropoietin group had higher rates of ICU admission (92% vs 50%, p = 0.004), return of spontaneous circulation (ROSC) (92% vs 53%, p = 0.006), 24-h survival (83% vs 47%, p = 0.008), and hospital survival (54% vs 20%, p = 0.011). However, after adjusting for pretreatment covariates only ICU admission and ROSC remained statistically significant. Compared with matched controls, the erythropoietin group had higher rates of ICU admission (92% vs 65%, p = 0.024) and 24-h survival (83% vs 52%, p = 0.014) with statistically insignificant higher ROSC (92% vs 71%, p = 0.060) and hospital survival (54% vs 31%, p = 0.063). However, after adjusting for pretreatment covariates all four outcomes were statistically significant. End-tidal PCO₂ (an estimate of blood flow during chest compression) was higher in the erythropoietin group.

Conclusions

Erythropoietin given during CPR facilitates ROSC, ICU admission, 24-h survival, and hospital survival. This effect was consistent with myocardial protection leading to hemodynamically more effective CPR (Trial registration: http://isrctn.org. Identifier: ISRCTN67856342).     

Neurological prognostication by gender in out-of-hospital cardiac arrest patients receiving hypothermia treatment

Objectives

This study examined whether the extent to which out-of-hospital cardiac arrest (OHCA) patients recover neurological function after therapeutic hypothermia (TH) is augmented in specific gender, age, and primary ECG group.

Methods

A cross-sectional analysis was conducted using a nationwide database of OHCAs in Korea which was constructed from emergency medical services (EMS) run sheet and hospital medical record review between 2008 and 2012. Patients survived to admission were enrolled. Study endpoint was survival with neurological recovery (cerebral performance category 1 and 2). Main exposure was hypothermia. Gender, age group (<45, 45–65, and >65 years old) and primary ECG rhythm were considered as potential effect modifiers. Potential factors were accounted for adjustment using multivariable logistic regression.

Results

Survival with good neurological recovery was 14.6% (9.3% in men and 17.2% in women). TH was performed in 15.5% (n = 1140). Strata-specific crude analysis showed enhanced neurological recovery for women of childbearing ages compared to men counterparts (OR = 4.38 (1.39, 13.74) vs. OR = 1.73 (0.97, 3.10)). After adjusted for effect modifiers and covariates, the strongest effect of TH on neurological recovery was observed in men younger than 45 years of age with shockable rhythm (OR = 2.00 (1.26, 3.19)), whereby no statistically significant associations were found in all women. In both genders, the magnitude of association decreased with age and having non-shockable cardiac rhythm.

Conclusion

TH was the strongest indicator for good neurological recovery in <45-year old men with shockable cardiac rhythm. Across all age groups, women were less likely to benefit from TH than men.     

Survival rates in out-of-hospital cardiac arrest patients transported without prehospital return of spontaneous circulation: An observational cohort study

Background

Some Emergency Medical Services currently use just one component of the Universal Termination of Resuscitation (TOR) Guideline, the absence of prehospital return of spontaneous circulation (ROSC), as the single criteria to terminate resuscitation, which may deny transport to potential survivors.

Objective

This study aimed to report the survival to hospital discharge rate in non-traumatic, adult out-of-hospital cardiac arrest (OHCA) patients transported to hospital without a prehospital ROSC.

Methods

An observational study of OHCA patients without a prehospital ROSC who met the Universal TOR Guideline for transport to hospital with ongoing resuscitation. Multivariable logistic regression was used to determine the association of each variable with survival to hospital discharge.

Results

Of 20,207 OHCA treated by EMS, 3374 (16.4%) did not have a prehospital ROSC but met the Universal TOR guideline for transport to hospital with ongoing resuscitation. Of these patients, 122 (3.6%) survived to hospital discharge. Survival to discharge was associated with initial shockable VF/VT rhythms (OR 5.07; 95% CI 2.77–9.30), EMS-witnessed arrests (OR 3.51; 95% CI 1.73–7.15), bystander-witnessed arrests (OR 2.11; 95% CI 1.18–3.77), and public locations (OR 1.57; 95% CI 1.02–2.40).

Conclusion

In OHCA patients without a prehospital ROSC who met the Universal TOR Guideline for transport with ongoing resuscitation survival rates were above the 1% futility rate. Employing only the lack of ROSC as criteria for termination of resuscitation may miss survivors after OHCA.     

Systematic downloading and analysis of data from automated external defibrillators used in out-of-hospital cardiac arrest

Background

Valuable information can be retrieved from automated external defibrillators (AEDs) used in victims of out-of-hospital cardiac arrest (OHCA). We describe our experience with systematic downloading of data from deployed AEDs. The primary aim was to compare the proportion of shockable rhythm from AEDs used by laypersons with the corresponding proportion recorded by the Emergency Medical Services (EMS) on arrival.

Methods

In a 20-month study, we collected data on OHCAs in the Capital Region of Denmark where an AED was deployed prior to arrival of EMS. The AEDs were brought to the emergency medical dispatch centre for data downloading and rhythm analysis. Patient data were retrieved from the medical records from the admitting hospital, whereas data on EMS rhythm analyses were obtained from the Danish Cardiac Arrest Register between 2001 and 2010.

Results

A total of 121 AEDs were deployed, of which 91 cases were OHCAs with presumed cardiac origin. The prevalence of initial shockable rhythm was 55.0% (95% CI [44.7–64.8%]). This was significantly greater than the proportion recorded by the EMS (27.6%, 95% CI [27.0–28.3%], p < 0.0001). Shockable arrests were significantly more likely to be witnessed (92% vs. 34%, p < 0.0001) and the bystander CPR rate was higher (98% vs. 85%, p = 0.04). More patients with initial shockable rhythm achieved return of spontaneous circulation upon hospital arrival (88% vs. 7%, p < 0.0001) and had higher 30-day survival rate (72% vs. 5%, p < 0.0001).

Conclusion

AEDs used by laypersons revealed a higher proportion of shockable rhythms compared to the EMS rhythm analyses.     

Reduced effectiveness of vasopressin in repeated doses for patients undergoing prolonged cardiopulmonary resuscitation

Introduction

The efficacy of repeated administration of vasopressin alone during prolonged cardiopulmonary resuscitation (CPR) remains unconfirmed. This study was conducted to estimate the effectiveness of the repeated administration of vasopressin vs. epinephrine for cardiopulmonary arrest (CPA) patients receiving prolonged CPR.

Methods

We conducted a prospective randomized controlled study on patients who experienced out-of-hospital CPA. The patients were randomly assigned to receive a maximum of four injections of either 40 IU of vasopressin (vasopressin group) or 1 mg of epinephrine (epinephrine group) immediately after emergency room (ER) admission. Patients who received vasopressors before ER admission or suffered non-cardiogenic CPA were excluded after randomization.

Results

In total, 336 patients were enrolled (vasopressin group, n = 137; epinephrine group, n = 118). No differences were found between these groups (vasopressin group vs. epinephrine group) in the rates of return of spontaneous circulation (ROSC) (28.7% vs. 26.6%), 24-h survival (16.9% vs. 20.3%), or survival to hospital discharge (5.6% vs. 3.8%). In a subgroup analysis by the Fisher's exact test, the rate of ROSC was higher in the vasopressin group than in the epinephrine group, among the patients whose arrests were witnessed (48.1% vs. 27.8%, p = 0.010) or who received bystander CPR (68.0% vs. 38.5%, p = 0.033). When the independent predictors of ROSC were calculated in the subgroup analysis, however, vasopressin administration (Odds ratio: 0.87–0.28) did not affect the outcome.

Conclusions

This is the first report of a possible vasopressin-alone resuscitation without additional epinephrine. However, repeated injections of either vasopressin or epinephrine during prolonged advanced cardiac life support resulted in comparable survival.     

Evaluation of pre-arrest morbidity score and prognosis after resuscitation score and other clinical variables associated with in-hospital cardiac arrest in southern Sweden

Objective

To evaluate pre-arrest morbidity score (PAM), prognosis after resuscitation score (PAR) and to identify additional clinical variables associated with survival after in-hospital cardiac arrest (IHCA) treated with cardiopulmonary resuscitation (CPR).

Methods

A retrospective observational study involving all cases of IHCA at Skåne University Hospital Malmö 2007–2010.

Results

Two-hundred-eighty-seven cases of IHCA were identified (61.3% male; mean age 70 years) of whom 20.2% survived until discharge. The odds ratio (95% confidence interval) for death prior to discharge was 6.49 (1.50–28.19) (p = 0.013) for PAM > 6 and 3.88 (1.95–7.73) (p < 0.001) for PAR > 4. At PAM- and PAR-scores >5, specificity exceeded 90%, while sensitivity was only 20–30%. The odds ratio for in-hospital mortality was 0.38 (0.20–0.72) (p = 0.003) for patients with cardiac monitoring, 9.86 (5.08–19.12) (p < 0.001) for non-shockable vs shockable rhythm, 0.32 (0.15–0.69) (p = 0.004) for presence of ST-elevation myocardial infarction (STEMI), 0.27 (0.09–0.78) (p = 0.016) for patients with independent Activities of Daily Life (ADL) and 13.86 (1.86–103.46) (p = 0.010) for patients with malignancies. Heart rate (HR) on admission (per bpm) [1.024 (1.009–1.040) (p = 0.002)] and sodium plasma concentration on admission (per mmol l⁻¹) [0.92 (0.85–0.99) (p = 0.023)] were significantly associated with in-hospital mortality.

Conclusion

PAM- and PAR-scores do not sufficiently discriminate between in-hospital death and survival after IHCA to be used as clinical tools guiding CPR decisions. We confirm that malignancy is associated with increased in-hospital mortality, and cardiac monitoring, shockable rhythm, STEMI and independent ADL, with decreased in-hospital mortality. Interestingly, our results suggest that HR and plasma sodium concentration upon admission may represent new tools for risk stratification.     

The effect of time to defibrillation and targeted temperature management on functional survival after out-of-hospital cardiac arrest

Background

Cardiac arrest physiology has been proposed to occur in three distinct phases: electrical, circulatory and metabolic. There is limited research evaluating the relationship of the 3-phase model of cardiac arrest to functional survival at hospital discharge. Furthermore, the effect of post-cardiac arrest targeted temperature management (TTM) on functional survival during each phase is unknown.

Objective

To determine the effect of TTM on the relationship between the time of initial defibrillation during each phase of cardiac arrest and functional survival at hospital discharge.

Methods

This was a retrospective observational study of consecutive adult (≥18 years) out-of-hospital cardiac arrest (OHCA) patients with initial shockable rhythms. Included patients obtained a return of spontaneous circulation (ROSC) and were eligible for TTM. Multivariable logistic regression was used to determine predictors of functional survival at hospital discharge.

Results

There were 20,165 OHCA treated by EMS and 871 patients were eligible for TTM. Of these patients, 622 (71.4%) survived to hospital discharge and 487 (55.9%) had good functional survival. Good functional survival was associated with younger age (OR 0.94; 95% CI 0.93–0.95), shorter times from collapse to initial defibrillation (OR 0.73; 95% CI 0.65–0.82), and use of post-cardiac arrest TTM (OR 1.49; 95% CI 1.07–2.30). Functional survival decreased during each phase of the model (65.3% vs. 61.7% vs. 50.2%, P < 0.001).

Conclusion

Functional survival at hospital discharge was associated with shorter times to initial defibrillation and was decreased during each successive phase of the 3-phase model. Post-cardiac arrest TTM was associated with improved functional survival.     

Adrenaline for out-of-hospital cardiac arrest resuscitation: A systematic review and meta-analysis of randomized controlled trials

Introduction

The evidence for adrenaline in out-of-hospital cardiac arrest (OHCA) resuscitation is inconclusive. We systematically reviewed the efficacy of adrenaline for adult OHCA.

Methods

We searched in MEDLINE, EMBASE, and Cochrane Library from inception to July 2013 for randomized controlled trials (RCTs) evaluating standard dose adrenaline (SDA) to placebo, high dose adrenaline (HDA), or vasopressin (alone or combination) in adult OHCA patients. Meta-analyses were performed using random effects modeling. Subgroup analyses were performed stratified by cardiac rhythm and by number of drug doses. The primary outcome was survival to discharge and the secondary outcomes were return of spontaneous circulation (ROSC), survival to admission, and neurological outcome.

Results

Fourteen RCTs (n = 12,246) met inclusion criteria: one compared SDA to placebo (n = 534), six compared SDA to HDA (n = 6174), six compared SDA to an adrenaline/vasopressin combination (n = 5202), and one compared SDA to vasopressin alone (n = 336). There was no survival to discharge or neurological outcome differences in any comparison group, including subgroup analyses. SDA showed improved ROSC (RR 2.80, 95%CI 1.78–4.41, p < 0.001) and survival to admission (RR 1.95, 95%CI 1.34–2.84, p < 0.001) compared to placebo. SDA showed decreased ROSC (RR 0.85, 95%CI 0.75–0.97, p = 0.02; I² = 48%) and survival to admission (RR 0.87, 95%CI 0.76–1.00, p = 0.049; I² = 34%) compared to HDA. There were no differences in outcomes between SDA and vasopressin alone or in combination with adrenaline.

Conclusions

There was no benefit of adrenaline in survival to discharge or neurological outcomes. There were improved rates of survival to admission and ROSC with SDA over placebo and HDA over SDA.     

The effect of adherence to ACLS protocols on survival of event in the setting of in-hospital cardiac arrest

Aim

Advanced Cardiac Life Support (ACLS) algorithms are the default standard of care for in-hospital cardiac arrest (IHCA) management. However, adherence to published guidelines is relatively poor. The records of 149 patients who experienced IHCA were examined to begin to understand the association between overall adherence to ACLS protocols and successful return of spontaneous circulation (ROSC).

Methods

A retrospective chart review of medical records and code team worksheets was conducted for 75 patients who had ROSC after an IHCA event (SE group) and 74 who did not survive an IHCA event (DNS group). Protocol adherence was assessed using a detailed checklist based on the 2005 ACLS Update protocols. Several additional patient characteristics and circumstances were also examined as potential predictors of ROSC.

Results

In unadjusted analyses, the percentage of correct steps performed was positively correlated with ROSC from an IHCA (p < 0.01), and the number of errors of commission and omission were both negatively correlated with ROSC from an IHCA (p < 0.01). In multivariable models, the percentage of correct steps performed and the number of errors of commission and omission remained significantly predictive of ROSC (p < 0.01 and p < 0.0001, respectively) even after accounting for confounders such as the difference in age and location of the IHCAs.

Conclusions

Our results show that adherence to ACLS protocols throughout an event is correlated with increased ROSC in the setting of cardiac arrest. Furthermore, the results suggest that, in addition to correct actions, both wrong actions and omissions of indicated actions lead to decreased ROSC after IHCA.     

Resuscitation of patients suffering from sudden cardiac arrests in nursing homes is not futile

Background

Survival after out-of-hospital cardiac arrest (OHCA) has increased in recent years, and new data are therefore needed to avoid unsubstantiated statements when debating futility of resuscitation attempts following OHCA in nursing home (NH)-residents. We aimed to investigate the outcome and prognosis after OHCA in NH.

Methods

Consecutive Emergency Medical Service (EMS) attended OHCA-patients in Copenhagen during 2007–2011 were included. Utstein-criteria for pre-hospital data and review of individual patient charts for in-hospital post-resuscitation care were collected.

Results

A total of 2541 consecutive OHCA-patients were recorded, 245 (10%) of who were current NH-residents. NH-patients were older, more frequently female, had more witnessed arrests, fewer shockable primary rhythm and assumed cardiac aetiology, but shorter time to the return of spontaneous circulation (ROSC) compared to OHCA in non-nursing homes (non-NH). Overall 30-day survival rate was 9% in NH and 18% in non-NH, p < 0.001. Of the 245 NH-arrests 79 (32%) patients were admitted to hospital compared to 937 (41%) from non-NH (p < 0.001). Thirty-day survival rate in patients admitted to hospital were 27% for NH- and 42% for non-NH-patients, p < 0.001. OHCA in NH was, however, not associated with a significantly worse prognosis (HR = 0.88 (0.64–1.21), p = 0.4) after adjustment for known prognostic factors including co-morbidity.

Conclusions

Nursing home residents resuscitated from OHCA and admitted to hospital have similar survival rates as non-NH-patients when adjusting for known prognostic factors and pre-existing co-morbidity. A policy of not attempting resuscitation in nursing homes at all may therefore not be justified.