Comparison of Neurological Outcome between Tracheal Intubation and Supraglottic Airway Device Insertion of Out-of-hospital Cardiac Arrest Patients: A Nationwide, Population-based, Observational Study

The Journal of Emergency Medicine: Volume 44, Issue 2 , Pages 389-397, February 2013

© Gary Wilson/ Pre-hospital Research Forum

The effect of prehospital use of supraglottic airway devices as an alternative to tracheal intubation on long-term outcomes of patients with out-of-hospital cardiac arrest is unclear.

The authors compared the neurological outcomes of patients who underwent supraglottic airway device insertion with those who underwent tracheal intubation.

They conducted a nationwide population-based observational study using a national database containing all out-of-hospital cardiac arrest cases in Japan over a 3-year period (2005–2007). The rates of neurologically favorable 1-month survival (primary outcome) and of 1-month survival and return of spontaneous circulation before hospital arrival (secondary outcomes) were examined. Multiple logistic regression analyses were performed to adjust for potential confounders. Advanced airway devices were used in 138,248 of 318,141 patients, including an endotracheal tube (ETT) in 16,054 patients (12%), a laryngeal mask airway (LMA) in 34,125 patients (25%), and an oesophageal obturator airway (EOA) in 88,069 patients (63%).

The overall rate of neurologically favorable 1-month survival was 1.03% (1426/137,880). The rates of neurologically favorable 1-month survival were 1.14% (183/16,028) in the ETT group, 0.98% (333/34,059) in the LMA group, and 1.04% (910/87,793) in the EOA group. Compared with the ETT group, the rates were significantly lower in the LMA group (adjusted odds ratio 0.77, 95% confidence interval [CI] 0.64–0.94) and EOA group (adjusted odds ratio 0.81, 95% CI 0.68–0.96).

The authors found that prehospital use of supraglottic airway devices was associated with slightly, but significantly, poorer neurological outcomes compared with tracheal intubation, but neurological outcomes remained poor overall.

http://www.jem-journal.com/article/S0736-4679(12)00247-8/abstract?elsca1=etoc&elsca2=email&elsca3=0736-4679_201302_44_2&elsca4=emergency_medicine

Prehospital Continuous Positive Airway Pressure for Acute Respiratory Failure: A Systematic Review and Meta-Analysis

Prehospital Emergency Care: Posted online on February 1, 2013.

Acute respiratory failure (ARF) is a common problem encountered by emergency medical services and is associated with significant morbidity, mortality, and health care costs. Continuous positive airway pressure (CPAP) is an integral part of the hospital treatment of acute ARF, predominantly because of congestive heart failure. Intuitively, better patient outcomes may be achieved when CPAP is applied early in the prehospital setting, but there are few outcome studies to validate its use in this setting.

© Gary Wilson/ Pre-hospital Research Forum

This systematic review and meta-analysis aimed to examine the effectiveness of CPAP in the prehospital setting for patients with ARF. A literature review of bibliographic databases and secondary sources was conducted and potential papers were assessed by two independent reviewers. Included studies were those that compared CPAP therapy (and usual care) with no CPAP for ARF in the prehospital setting. Studies of other methods of noninvasive ventilation were not included. Methodologic quality was assessed using guidelines from the Cochrane Collaboration. Outcomes included the number of intubations, mortality, physiologic parameters, and dyspnea score. Forrest plots were constructed to estimate the pooled effect of CPAP on outcomes.

Five studies (1,002 patients) met the selection criteria—three randomized controlled trials (RCTs), a nonrandomised comparative study, and a retrospective comparative study using chart review. Forty-seven percent of the patients were allocated to the CPAP group. Baseline characteristics were similar between groups. The pooled estimates demonstrated significantly fewer intubations (odds ratio [OR] 0.31) and lower mortality (OR 0.41) in the CPAP group.

According to the authors, the studies included in this review showed a reduction in the number of intubations and mortality in patients with ARF who received CPAP in the prehospital setting. Recognising that the results may not be applicable to other health care contexts because of the inherent differences in the organisation and staffing of the EMS systems, the authors believe information from large RCTs on the efficacy of CPAP initiated early in the prehospital setting is critical to establishing the evidence base underpinning this therapy before ambulance services incorporate CPAP as routine clinical practice.

http://informahealthcare.com/doi/abs/10.3109/10903127.2012.749967

Drowning related out-of-hospital cardiac arrests: Characteristics and outcomes

Resuscitation: Online 29 January 2013

There are few studies on drowning-related out-of-hospital cardiac arrest (OHCA) in which patients are followed from the scene through to hospital discharge. The aim of the study was to describe this population and their outcomes in the state of Victoria (Australia).

© Gary Wilson/ Pre-hospital Research Forum

The Victorian Ambulance Cardiac Arrest Registry was searched for all cases of OHCA with a precipitating event of drowning attended by emergency medical services (EMS) between October 1999 and December 2011.

EMS attended 336 drowning-related OHCA during the study period. Cases frequently occurred in summer (45%) and the majority of patients were male (70%) and adult (77%). EMS resuscitation was attempted on 154 (46%) patients. Of these patients, 41 (27%) survived to hospital arrival and 12 (8%) survived to hospital discharge (5 adults [6%] and 7 [12%] children). Few patients were found in a shockable rhythm (6%), with the majority presenting in asystole (79%) or pulse-less electrical activity (13%). An initial shockable rhythm was found to positively predict survival (AOR 48.70) while increased EMS response time (AOR 0.73) and salt water drowning (AOR 0.69) were found to negatively predict survival.

Rates of survival in OHCA caused by drowning were found to be comparable to other OHCA causes. The authors found that patients were more likely to survive if they did not drown in salt water, had a quick EMS response and they were found in a shockable rhythm. They believe the prevention efforts and reducing EMS response time are likely to improve survival of drowning patients.

http://www.sciencedirect.com/science/article/pii/S0300957213000518