Out of hospital cardiac arrest in Western Sydney-an analysis of outcomes and estimation of future eCPR eligibility

Background

Refractory out of hospital cardiac arrest (OHCA) is associated with extremely poor outcomes. However, in selected patients extracorporeal cardiopulmonary resuscitation (eCPR) may be an effective rescue therapy, allowing time treat reversible causes. The primary goal was to estimate the potential future caseload of eCPR at historically 'low-volume' extracorporeal membrane oxygenation (ECMO) centres.

Methods

A 3-year observational study of OHCA presenting to the Emergency Department (ED of an urban referral centre without historical protocolised use of eCPR. Demographics and standard Utstein outcomes are reported. Further, an a priori analysis of each case for potential eCPR eligibility was conducted. A current eCPR selection criteria (from the 2-CHEER study) was used to determine eligibly.

Results

In the study window 248 eligible cardiac arrest cases were included in the OHCA registry. 30-day survival was 23.4% (n = 58). The mean age of survivors was 55.4 years. 17 (6.8%) cases were deemed true refractory arrests and fulfilled the 2-CHEER eligibility criteria. The majority of these cases presented within “office hours” and no case obtained a return of spontaneous circulation standard advanced life support.

Conclusions

In this contemporary OHCA registry a significant number of refractory cases were deemed potential eCPR candidates reflecting a need for future interdisciplinary work to support delivery of this therapy.

The association between scene time interval and neurologic outcome following adult bystander witnessed out-of-hospital cardiac arrest

OBJECTIVE

To analyze the association between Emergency Medical Services (EMS) scene time interval (STI) and survival with functional neurologic recovery following adult out-of-hospital cardiac arrest (OHCA).

METHODS

A retrospective analysis of prospectively collected data from the national Cardiac Arrest Registry to Enhance Survival from January 2013 to December 2018. All adult non-traumatic, EMS-treated, bystander-witnessed OHCA with complete data were included. Patients with STI times >60 min, defined as the time from EMS arrival at the patient's side to the time the transport vehicle left the scene, unwitnessed OHCA, nursing home events, EMS-witnessed OHCA, or patients with termination of resuscitation in the field were excluded. The primary outcome was survival with functional recovery (Cerebral Performance Category [CPC] = 1 or 2). Multivariable logistic regression was used to quantify the association of STI with the primary.

OUTCOME

RESULTS

67,237 patients met inclusion criteria with 12,098 (18.0%) surviving with functional recovery. Mean STI (SD) for survivors with CPC 1 or 2 was 19 (8.4) and 22.8 (10.5) for those with poor outcomes (death or CPC 3-4; p < 0.001). For every 1-min increase in STI, the adjusted odds of a poor outcome increased by 3.5%; odds ratio = 1.035; 95% CI (1.027, 1.044); p < 0.001. Restricted cubic spline analysis showed increased risk of poor outcome after approximately 20 min.

CONCLUSION

Longer STI times are strongly associated with poor neurologic outcome in bystander-witnessed OHCA patients. After a STI duration of approximately 20 min, the associated risk of a poor neurologic outcome increased more rapidly.

Does care at a cardiac arrest centre improve outcome after out-of-hospital cardiac arrest? - A systematic review

AIM

To perform a systematic review to answer 'In adults with attempted resuscitation after non-traumatic cardiac arrest does care at a specialised cardiac arrest centre (CAC) compared to care in a healthcare facility not designated as a specialised cardiac arrest centre improve patient outcomes?'

METHODS

The PRISMA guidelines were followed. We searched bibliographic databases (Embase, MEDLINE and the Cochrane Library (CENTRAL)) from inception to 1st August 2018. Randomised controlled trials (RCTs) and non-randomised studies were eligible for inclusion. Two reviewers independently scrutinized studies for relevance, extracted data and assessed quality of studies. Risk of bias of studies and quality of evidence were assessed using ROBINS-I tool and GRADEpro respectively. Primary outcomes were survival to 30 days with favourable neurological outcomes and survival to hospital discharge with favourable neurological outcomes. Secondary outcomes were survival to 30 days, survival to hospital discharge and return of spontaneous circulation (ROSC) post-hospital arrival for patients with ongoing resuscitation. This systematic review was registered in PROSPERO (CRD 42018093369) RESULTS: We included data from 17 observational studies on out-of-hospital cardiac arrest (OHCA) patients in meta-analyses. Overall, the certainty of evidence was very low. Pooling data from only adjusted analyses, care at CAC was not associated with increased likelihood of survival to 30 days with favourable neurological outcome (OR 2.92, 95% CI 0.68-12.48) and survival to 30 days (OR 2.14, 95% CI 0.73-6.29) compared to care at other hospitals. Whereas patients cared for at CACs had improved survival to hospital discharge with favourable neurological outcomes (OR 2.22, 95% CI 1.74-2.84) and survival to hospital discharge (OR 1.85, 95% CI 1.46-2.34).

CONCLUSIONS

Very low certainty of evidence suggests that post-cardiac arrest care at CACs is associated with improved outcomes at hospital discharge. There remains a need for high quality data to fully elucidate the impact of CACs.

Refractory out-of-hospital cardiac arrest with ongoing cardiopulmonary resuscitation at hospital arrival - survival and neurological outcome without extracorporeal cardiopulmonary resuscitation

Background

The prognosis in refractory out-of-hospital cardiac arrest (OHCA) with ongoing cardiopulmonary resuscitation (CPR) at hospital arrival is often considered dismal. The use of extracorporeal cardiopulmonary resuscitation (eCPR) for perfusion enhancement during resuscitation has shown variable results. We aimed to investigate outcome in refractory OHCA patients managed conservatively without use of eCPR.

Methods

We included consecutive OHCA patients with refractory arrest or prehospital return of spontaneous circulation (ROSC) in the Copenhagen area in 2002–2011.

Results

A total of 3992 OHCA patients with resuscitation attempts were included; in 2599, treatment was terminated prehospital, and 1393 (35%) were brought to the hospital either with ROSC (n = 1285, 92%) or with refractory OHCA (n = 108, 8%). Of patients brought in with refractory OHCA, 56 (52%) achieved ROSC in the emergency department. There were no differences between patients with refractory OHCA or prehospital ROSC with regard to age, sex, comorbidities, or etiology of OHCA. Time to emergency medical services (EMS) arrival was similar, whereas time to ROSC (when ROSC was achieved) was longer in refractory OHCA patients (EMS, 6 (5–9] vs. 7 [5–10] min, p = 0.8; ROSC, 15 [9–22] vs. 27 [20–41] min, p < 0.001). Independent factors associated with transport with refractory OHCA instead of prehospital termination of therapy were OHCA in public (OR, 3.6 [95% CI, 2.2–5.8]; p < 0.001), witnessed OHCA (OR, 3.7 [2.0–7.1]; p < 0.001), shockable rhythm (OR, 3.0 [1.9–4.7]; p < 0.001), younger age (OR, 1.2 [1.1–1.2]; p < 0.001), and later calendar year (OR, 1.4 [1.2–1.6]; p < 0.001). Thirty-day survival was 20% in patients with refractory OHCA compared with 42% in patients with prehospital ROSC (p < 0.001). Four of 28 refractory OHCA patients with duration of resuscitation > 60 min achieved ROSC. No difference in favorable neurological outcome in patients surviving to discharge was found (prehospital ROSC 84% vs. refractory OHCA 86%; p = 0.7).

Conclusions

Survival after refractory OHCA with ongoing CPR at hospital arrival was significantly lower than among patients with prehospital ROSC. Despite a lower survival, the majority of survivors with both refractory OHCA and prehospital ROSC were discharged with a similar degree of favorable neurological outcome, indicating that continued efforts in spite of refractory OHCA are not in vain and may still lead to favorable outcome even without eCPR.

[Which patients benefit from transport with ongoing cardiopulmonary resuscitation? : Retrospective analysis of 70 patients with refractory preclinical cardiac arrest]

BACKGROUND

Mortality in patients with out-of-hospital cardiac arrest (OHCA) remains very high despite advances in resuscitation algorithms. Most of these patients die at the scene and do not reach hospital. It is currently the subject of discussion whether transport to hospital with ongoing cardiopulmonary resuscitation (CPR) improves survival and neurological outcome in patients with OHCA.

OBJECTIVE

The aim of this study was to identify predictors of survival and good neurological outcome in patients after OHCA who were transported to hospital with ongoing CPR.

PATIENTS AND METHODS

A total of 70 consecutive patients with refractory OHCA (mean age 54.7 ± 15 years) transported to hospital with ongoing CPR were retrospectively analyzed. Neurological outcome was assessed after 30 days based on the Glasgow-Pittsburgh cerebral performance category (CPC).

RESULTS

After 30 days 82.9% of the patients enrolled in the trial died (CPC score of 5), 8 patients (11.4%) showed a good neurological recovery with CPC scores of 1-2 and 4 patients (5.7%) had a poor neurological outcome with CPC scores of 3-4. Predictors of good neurological outcome were witnessed arrest, initial defibrillatable rhythm and serum lactate levels on admission. In all patients with good outcome, the index event for OHCA was from cardiac causes.

CONCLUSION

Selected patient collectives can benefit from transport to hospital with ongoing cardiopulmonary resuscitation (CPR).

Emergency medical service treated out-of-hospital cardiac arrest: Identification of weak links in the chain-of-survival through an epidemiological study

BACKGROUND

In-depth analysis of emergency medical services (EMSs) performances in out-of-hospital cardiac arrest (OHCA) promotes quality improvement.

AIMS

The purpose of this study was to identify the improvable factors of the EMS response to OHCA through the description and analysis of OHCA incidence, characteristics, management and outcome.

METHODS

This was a retrospective cohort study on all OHCA patients treated by the EMSs of the district of Trieste, Italy (236,556 inhabitants) in 2011.

RESULTS

A total of 678 OHCAs occurred and 142 (20.1%) underwent cardiopulmonary resuscitation (CPR), with a respective incidence of 287/100,000/year and 60/100,000/year. The incidence of shockable rhythms in the CPR group was 13/100,000. OHCAs occurred mainly during daytime, though the proportion of patients receiving CPR was significantly higher by night-time (p=0.01). Thirty-four CPR patients (23.9%) restored spontaneous circulation on scene; 12 (8.5%) survived to hospital discharge (11 with good neurological recovery). Survival was not correlated with age, while was significantly higher for patients with shockable rhythms (32.3%; p<0.001). Mean response time was 8 min. Direct intervention of physician-staffed units did not improve the outcome when compared with two-tiered activation. Patients immediately identified as OHCA by dispatch nurses and those undergoing therapeutic hypothermia showed a non-significant trend towards improved survival (p=0.09 and 0.07, respectively).

CONCLUSIONS

OHCA identification by dispatch nurses and reduction of response time were the factors most susceptible to improvement.

Transport with ongoing resuscitation: a comparison between manual and mechanical compression

AIM

In special circumstances it may be necessary to transport out-of-hospital cardiac arrest patients with ongoing resuscitation to the hospital. External mechanical chest compression devices could be an alternative for these resuscitations. The study compares manual chest compression with external mechanical devices and a semiautomatic device in transport conditions using a resuscitation manikin.

METHODS

Manual chest compressions were compared with LUCAS 2, AutoPulse and animax mono devices using the Ambu Man Wireless MegaCode manikin (10 series each). The measurements were performed in a standard ambulance vehicle during transport on a predefined track of 5.0 km.

RESULTS

Mean compression frequencies in the manual group (117 ± 18 min(-1)) and in the animax mono group (115 ± 10 min(-1)) were significantly higher than in the LUCAS 2 group (100 min(-1), p=0.02) and the AutoPulse group (80 min(-1), p<0.01). Both mechanical devices worked absolutely constantly. Only the animax mono group reached with 51.2 mm the recommended compression depth. The quality of manual compressions decreased considerably during braking or change manoeuvres while the mechanical devices continued to work constantly.

CONCLUSIONS

During a patient transport with ongoing resuscitation, external mechanical compression devices may be a good alternative to manual compression because they increase the safety of the rescuer and patient. Yet, in this study only animax mono reached the guideline specifications regarding chest compressions' frequency and depth. Concerning constancy, the mechanical devices work reliably and more independently from motion influences. Further studies are necessary to evaluate the effectiveness of these devices in patient transport.

Randomized crossover trial comparing physical strain on advanced life support providers during transportation using real-time automated feedback

BACKGROUND

Feedback devices provide verbal and visual real-time information on cardiopulmonary resuscitation (CPR) quality. Feedback devices can improve the quality of CPR during transportation. It remains unclear if feedback has an effect on the physical strain felt by providers during ongoing CPR.

OBJECTIVES

The objective was to assess the influence of real-time automated feedback on physical strain of rescuers during ongoing chest compressions in different means of transportation.

METHODS

The study was a randomized crossover trial comparing physical strain on advanced life support (ALS) providers during chest compressions using real-time automated feedback in different transport environments: 1) a moving ambulance and 2) a flying helicopter. The authors measured objective and subjective measures of physical strain and calculated the difference in the rate pressure product (RPP) after 8 minutes of external chest compressions.

RESULTS

There was no difference in the RPP (mean intraindividual difference = 21; 95% confidence interval [CI] = -1,438 to 1,480; p = 0.98) between using the feedback device versus no feedback. There was no significant interaction of vehicle type on the effect of feedback on the RPP. Feedback resulted in a significant mean perceived exertion reduction of a Borg scale score by 0.89 points (95% CI = 0.42 to 1.35; p < 0.001). For systolic and diastolic blood pressure, for serum lactate concentrations, and for the modified Nine Hole Peg Test (NHPT; measurement of fine motor skills), we found no statistically significant differences.

CONCLUSIONS

Feedback devices for CPR during transportation do not have an effect on objective components of physical strain, but decrease perceived exertion in experienced rescuers in an experimental setting.

Quality of cardiopulmonary resuscitation in out-of-hospital cardiac arrest is hampered by interruptions in chest compressions--a nationwide prospective feasibility study

AIM OF THE STUDY

Quality of cardiopulmonary resuscitation (CPR) is a critical determinant of outcome following out-of-hospital cardiac arrest. The aim of our study was to evaluate the quality of CPR provided by emergency medical service providers (Basic Life Support (BLS) capability) and emergency medical service providers assisted by paramedics, nurse anesthetists or physician-manned ambulances (Advanced Life Support (ALS) capability) in a nationwide, unselected cohort of out-of-hospital cardiac arrest cases.

METHODS

We conducted a prospective, observational study of out-of-hospital cardiac arrest with non-traumatic etiology (>18 years of age) occurring from the 1st to the 31st of January 2009 and treated by the primary Danish emergency medical service operator, covering approximately 85% of the population. One hundred and ninety-one cases were eligible for analysis. Follow-up was up to one year or death. Quality of CPR was evaluated using measurements of transthoracic impedance.

RESULTS

The majority of patients were treated by ambulances with ALS capability (54%). Interruptions in CPR related to loading of the patient into the emergency medical service vehicle were substantial, but independent of whether patients were managed by ALS or BLS capable units (222s versus 224s, P = 0.76) as were duration of interruptions during rhythm analysis alone (20s versus 22s, P = 0.33) and defibrillation (24s versus 26s, P = 0.07).

CONCLUSIONS

Nationwide, routine monitoring of transthoracic impedance is feasible. CPR is hampered by extended interruptions, particularly during loading of the patient into the emergency medical service vehicle, rhythm analysis and defibrillation.

The empirical basis for determinations of medical futility

BACKGROUND

Decisions to limit treatment in critically ill patients often rely on publications that make claims of futility based on outcome data. Our objective was to systematically review the criteria for futility and the strength of empirical evidence across clinical studies that purport to support or refute claims of futility.

METHODS

The MEDLINE database was searched for relevant articles published between 1980 and 2008. Selected studies reported original outcome data in critically ill or cardiac arrest patients and claimed that these data can support or refute decisions to limit treatment in comparable patients. Two authors independently abstracted data on patient characteristics, intervention, outcomes, cost, and design.

RESULTS

Forty seven studies supporting a claim of futility and 45 refuting it were reviewed. Median point estimate for adverse outcome in studies supporting claims of futility was 100% (range 75% to 100%); median lower 95% confidence limit was 91% (range 48% to 99%). Explicit thresholds for futility were missing in 88% of articles. The original criteria for quantitative futility were fulfilled by only 28% of data, and almost exclusively in studies of cardiopulmonary resuscitation (CPR) for cardiac arrest. Substantial statistical overlap was observed between data brought in support of futility claims and data brought to refute them.

CONCLUSIONS

Most studies that purport to guide determinations of futility are based on insufficient data to provide statistical confidence for clinical decision-making. They usually lack explicit a priori thresholds for determination of futility. Many studies draw disparate conclusions based on statistically similar data. In most circumstances these problems preclude confident determinations of futility.

The effect of transport on quality of cardiopulmonary resuscitation in out-of-hospital cardiac arrest

INTRODUCTION

Most manikin and clinical studies have found decreased quality of CPR during transport to hospital. We wanted to study quality of CPR before and during transport for out-of-hospital cardiac arrest patients and also whether quality of CPR before initiation of transport was different from the quality in patients only receiving CPR on scene.

MATERIALS AND METHODS

Quality of CPR was prospectively registered with a modified defibrillator for consecutive cases of out-of-hospital cardiac arrest in three ambulance services during 2002-2005. Ventilations were registered via changes in transthoracic impedance and chest compressions were measured with an extra chest compression pad placed on the patients' sternum. Paired t-tests were used to analyse quality of CPR before vs. during transport with ongoing CPR. Unpaired t-tests were used to compare CPR quality prior to transport to CPR quality in patients with CPR terminated on site.

RESULTS

Quality of CPR did not deteriorate during transport, but as previously reported overall quality of CPR was substandard. Quality of CPR performed on site was significantly better when transport was not initiated with ongoing CPR compared to episodes with initiation of transport during CPR: fraction of time without chest compressions was 0.45 and 0.53 (p<0.001), compression depth 37 mm and 34 mm (p=0.04), and number of chest compressions per minute 61 and 56 (p=0.01), respectively.

CONCLUSION

CPR quality was sub-standard both before and during transport. Early decision to transport might have negatively affected CPR quality from the early stages of resuscitation.