Influence of EMS-physician presence on survival after out-of-hospital cardiopulmonary resuscitation: systematic review and meta-analysis

Analysis of out-of-hospital cardiac arrest in Croatia - survival, bystander cardiopulmonary resuscitation, and impact of physician's experience on cardiac arrest management: a single center observational study

AIM

To analyze the initial rhythm, bystander cardiopulmonary resuscitation (CPR) rate, and survival after out-of-hospital cardiac arrests (OHCA) in Varaľdin County (Croatia), and to investigate whether physician's inexperience in emergency medical services (EMS) has an impact on resuscitation management.

METHODS

We reviewed clinical records and Revised Utstein cardiac arrest forms of all out-of-hospital resuscitations performed by EMS Varaľdin (EMSVz), Croatia, from 2007-2013. To analyze the impact of physician's inexperience in EMS (<1 year in EMS) on resuscitation management, we assessed physician's turnover in EMSVz, as well as OHCA survival, airway management, and adherence to resuscitation guidelines in regard to physician's EMS experience.

RESULTS

Of 276 patients (median age 68 years, interquartile range [IQR] 16; 198 male; 37% ventricular fibrillation/ventricular tachycardia, bystander CPR rate 25%), 80 were transferred to hospital and 39 were discharged (median survival after discharge 23 months, IQR 46 months). During the 7-year study period, 29 newly graduated physicians inexperienced in EMS started to work in EMSVz (performing 77 resuscitations), while 48% of them stayed for less than one year. Airway management depended on physician's EMS experience (P=0.018): inexperienced physicians performed bag-valve-mask ventilation (BMV) more than the experienced, with no impact on survival rate. Physician's EMS experience did not influence adherence to resuscitation guidelines (P=0.668), survival to hospital discharge (P=0.791), or survival time (P=0.405).

CONCLUSION

OHCA survival rate of EMSVz resuscitations was higher than in Europe, but bystander CPR needs to be improved. Compared to experienced physicians, inexperienced physicians preferred BMV over intubation, but with similar adherence to resuscitation guidelines and survival after OHCA.

Systematic review of the effectiveness of prehospital critical care following out-of-hospital cardiac arrest

BACKGROUND

Improving survival after out-of-hospital cardiac arrest (OHCA) is a priority for modern emergency medical services (EMS) and prehospital research. Advanced life support (ALS) is now the standard of care in most EMS. In some EMS, prehospital critical care providers are also dispatched to attend OHCA. This systematic review presents the evidence for prehospital critical care for OHCA, when compared to standard ALS care.

METHODS

We searched the following electronic databases: PubMed, EmBASE, CINAHL Plus and AMED (via EBSCO), Cochrane Database of Systematic Reviews, DARE, Cochrane Central Register of Controlled Trials, NHS Economic Evaluation Database, NIHR Health Technology Assessment Database, Google Scholar and ClinicalTrials.gov. Search terms related to cardiac arrest and prehospital critical care. All studies that compared patient-centred outcomes between prehospital critical care and ALS for OHCA were included.

RESULTS

The review identified six full text publications that matched the inclusion criteria, all of which are observational studies. Three studies showed no benefit from prehospital critical care but were underpowered with sample sizes of 1028-1851. The other three publications showed benefit from prehospital critical care delivered by physicians. However, an imbalance of prognostic factors and hospital treatment in these studies systematically favoured the prehospital critical care group.

CONCLUSION

Current evidence to support prehospital critical care for OHCA is limited by the logistic difficulties of undertaking high quality research in this area. Further research needs an appropriate sample size with adjustments for confounding factors in observational research design.

Characteristics and prognoses of patients treated by an anaesthesiologist-manned prehospital emergency care unit. A retrospective cohort study

OBJECTIVE

When planning and dimensioning an emergency medical system, knowledge of the population serviced is vital. The amount of literature concerning the prehospital population is sparse. In order to add to the current body of literature regarding prehospital treatment, thus aiding future public health planning, we describe the workload of a prehospital anaesthesiologist-manned mobile emergency care unit (MECU) and the total population it services in terms of factors associated with mortality.

PARTICIPANTS

The study is a register-based study investigating all missions carried out by a MECU operating in a mixed urban/rural area in Denmark from 1 May 2006 to 31 December 2014. Information on missions was extracted from the local MECU registry and linked at the individual level to the Danish population-based databases, the National Patient Registry and the Civil Registration System.

PRIMARY AND SECONDARY OUTCOME MEASURES

Primary outcome measures were number of missions and number of patient contacts. Secondary patient variables were mortality and association between mortality and age, sex, comorbidity, prior admission to hospital and response time.

RESULTS

The MECU completed 41 513 missions (mean 13.1 missions/day) having 32 873 patient contacts, corresponding to 19.2 missions and 15.2 patient encounters per 1000 patient years. Patient variables: the median age was 57 years (range 0-108 years), 42.8% (42.3% to 43.4%) were women. For patients admitted to hospital alive, 30-day mortality was 5.7% (5.4% to 6.0%); 90-day mortality was 8.1% (7.8% to 8.5%) while 2-year mortality was 16.4% (16.0% to 16.8%). Increasing age, male sex, comorbidity and prior admission to hospital but not response time were associated with mortality.

CONCLUSIONS

Mortality following an incident requiring the assistance of a MECU was high in the first 2 years following the incident. MECU response time assessed as a continuous parameter was not associated with patient outcome.

Extracorporeal cardiopulmonary resuscitation after out-of-hospital cardiac arrest in a Danish health region

BACKGROUND

Extracorporeal Cardiopulmonary Resuscitation (ECPR) has emerged as a feasible rescue therapy for refractory, normothermic out-of-hospital cardiac arrest (OHCA). Reported survival rates vary and comparison between studies is hampered by heterogeneous study populations, differences in bystander intervention and in pre-hospital emergency service organisation. We aimed to describe the first experiences, treatment details, complications and outcome with ECPR for OHCA in a Danish health region.

METHODS

Retrospective study of adult patients admitted at Aarhus University Hospital, Denmark between 1 January 2011 and 1 July 2015 with witnessed, refractory, normothermic OHCA treated with ECPR. OHCA was managed with pre-hospital advanced airway management and mechanical chest compression during transport. Relevant pre-hospital and in-hospital data were collected with special focus on low-flow time and ECPR duration. Survival to hospital discharge with Cerebral Performance Category (CPC) of 1 and 2 at hospital discharge was the primary endpoint.

RESULTS

Twenty-one patients were included. Median pre-hospital low-flow time was 54 min [range 5-100] and median total low-flow time was 121 min [range 55-192]. Seven patients survived (33%). Survivors had a CPC score of 1 or 2 at hospital discharge. Five survivors had a shockable initial rhythm. In all survivors coronary occlusion was the presumed cause of cardiac arrest.

CONCLUSION

Extracorporeal cardiopulmonary resuscitation is feasible as a rescue therapy in normothermic refractory OHCA in highly selected patients. Low-flow time was longer than previously reported. Survival with favourable neurological outcome is possible despite prolonged low-flow duration.