Prehospital endotracheal intubation: the controversy continues

Does prehospital management by doctors affect outcome in major trauma? A systematic review

BACKGROUND

There is substantial variation worldwide in prehospital management of trauma and the role of doctors is controversial. The objective of this review was to determine whether prehospital management by doctors affects outcomes in major trauma, including the prespecified subgroup of severe traumatic brain injuries when compared with management by other advanced life support providers.

METHODS

EMBASE, MEDLINE(R), PubMed, SciELO, Trip, Web of Science, and Zetoc were searched for published articles. HSRProj, OpenGrey, and the World Health Organization International Clinical Trials Registry Platform were searched for unpublished data. Relevant reference lists were hand-searched. There were no limits on publication year, but articles were limited to the English language. Authors were contacted for further information as required. Quality was assessed using the Downs and Black criteria. Mortality was the primary outcome, and disability was the secondary outcome of interest. Studies were subjected to a descriptive analysis alone without a meta-analysis due to significant study heterogeneity. All searches, quality assessment, data abstraction, and data analysis was performed by two reviewers independently.

RESULTS

Two thousand thirty-seven articles were identified, 49 full-text articles assessed and eight studies included. The included studies consisted of one randomized controlled trial with 375 participants and seven observational studies with over 4,451 participants. All included studies were at a moderate to high risk of bias. Six of the eight included studies showed an improved outcome with prehospital management by doctors, five in terms of mortality and one in terms of disability. Two studies found no significant difference.

CONCLUSION

There appears to be an association between prehospital management by doctors and improved survival in major trauma. There may also be an association with improved survival and better functional outcomes in severe traumatic brain injury. Further high-quality evidence is needed to confirm these findings.

LEVEL OF EVIDENCE

Systematic review, level III.

Prehospital endotracheal intubation: elemental or detrimental?

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2015 and co-published as a series in Critical Care. Other articles in the series can be found online at http://ccforum.com/series/annualupdate2015. Further information about the Annual Update in Intensive Care and Emergency Medicine is available from http://www.springer.com/series/8901.

The process of prehospital airway management: challenges and solutions during paramedic endotracheal intubation

OBJECTIVES

Endotracheal intubation success rates in the prehospital setting are variable. Our objective was to describe the challenges encountered and corrective actions taken during the process of endotracheal intubation by paramedics.

DESIGN

Analysis of prehospital airway management using a prospective registry that was linked to an emergency medical services administrative database.

SETTING

Emergency medical services system serving King County, Washington, 2006-2011. Paramedics in this system have the capability to administer neuromuscular blocking agents to facilitate intubation (i.e., rapid sequence intubation).

PATIENTS

A total of 7,523 patients more than 12 years old in whom paramedics attempted prehospital endotracheal intubation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

An intubation attempt was defined as the introduction of the laryngoscope into the patient's mouth, and the attempt concluded when the laryngoscope was removed from the mouth. Endotracheal intubation was successful on the first attempt in 77% and ultimately successful in 99% of patients (7,433 of 7,523). Paramedics used a rapid sequence intubation strategy on 54% of first attempts. Among the subset with a failed first attempt (n = 1,715), bodily fluids obstructing the laryngeal view (50%), obesity (28%), patient positioning (17%), and facial or spinal trauma (6%) were identified as challenges to intubation. A variety of adjustments were made to achieve intubation success, including upper airway suctioning (used in 43% of attempts resulting in success), patient repositioning (38%), rescue bougie use (19%), operator change (16%), and rescue rapid sequence intubation (6%). Surgical cricothyrotomy (0.4%, n = 27) and bag-valve-mask ventilation (0.8%, n = 60) were rarely performed by paramedics as final rescue airway strategies.

CONCLUSIONS

Airway management in the prehospital setting has substantial challenges. Success can require a collection of adjustments that involve equipment, personnel, and medication often in a simultaneous fashion.

Airways in out-of-hospital cardiac arrest: systematic review and meta-analysis

OBJECTIVE

To determine the differences in survival for out-of-hospital advanced airway intervention (AAI) compared with basic airway intervention (BAI) in cardiac arrest.

BACKGROUND

AAI is commonly utilized in cardiac arrest in the out-of-hospital setting as a means to secure the airway. Observational studies and clinical trials of AAI suggest that AAI is associated with worse outcomes in terms of survival. No controlled trials exist that compares AAI to BAI.

METHODS

We conducted a bias-adjusted meta-analysis on 17 observational studies. The outcomes were survival, short-term (return of spontaneous circulation and to hospital admission), and longer-term (to discharge, to one month survival). We undertook sensitivity analyses by analyzing patients separately: those who were 16 years and older, nontrauma only, and attempted versus successful AAI.

RESULTS

This meta-analysis included 388,878 patients. The short-term survival for AAI compared to BAI were overall OR 0.84(95% CI 0.62 to 1.13), for endotracheal intubation (ETI) OR 0.79 (95% CI 0.54 to 1.16), and for supraglottic airways (SGA) OR 0.59 (95% CI 0.39 to 0.89). Long-term survival for AAI were overall OR 0.49 (95% CI 0.37 to 0.65), for ETI OR 0.48 (95% CI 0.36 to 0.64), and for SGA OR 0.35 (95% CI 0.28 to 0.44). Sensitivity analyses shows that limiting analyses to adults, non-trauma victims, and instances where AAI was both attempted and successful did not alter results meaningfully. A third of all studies did not adjust for any other confounding factors that could impact on survival.

CONCLUSIONS

This meta-analysis shows decreased survival for AAIs used out-of-hospital in cardiac arrest, but are likely biased due to confounding, especially confounding by indication. A properly conducted prospective study or a controlled trial is urgently needed and are possible to do.

Prehospital emergency trauma care and management

Prehospital care of the trauma patient is continuing to evolve; however, the principles of airway maintenance, hemorrhage control, and appropriate resuscitative maneuvers remain central to the role of the emergency medical care provider. Recent changes in the regulations for research in emergency settings will allow randomized trials to proceed to test new devices, drugs, and resuscitative strategies in the prehospital environment. The creation of prehospital research networks will provide the appropriate infrastructure to greatly facilitate the development of new protocols and the execution of large-scale randomized trials with the potential to change current prehospital practice.

The incidence and significance of accidental hypothermia in major trauma--a prospective observational study

BACKGROUND

Serious sequelae have been associated with injured patients who are hypothermic (<35°C) including coagulopathy, acidosis, decreased myocardial contractility and risk of mortality.

AIM

Establish the incidence of accidental hypothermia in major trauma patients and identify causative factors.

METHOD

Prospective identification and subsequent review of 732 medical records of major trauma patients presenting to an Adult Major Trauma Centre was undertaken between January and December 2008. Multivariate analysis was performed using logistic regression. Significant and clinically relevant variables from univariate analysis were entered into multivariate models to evaluate determinants for hypothermia and for death. Goodness of fit was determined with the use of the Hosmer-Lemeshow statistic.

MAIN RESULTS

Overall mortality was 9.15%. The incidence of hypothermia was 13.25%. The mortality of patients with hypothermia was 29.9% with a threefold independent risk of death: OR (CI 95%) 3.44 (1.48-7.99), P = 0.04. Independent determinants for hypothermia were pre-hospital intubation: OR (CI 95%) 5.18 (2.77-9.71), P < 0.001, Injury Severity Score (ISS): 1.04 (1.01-1.06), P = 0.01, Arrival Systolic Blood Pressure (ASBP) < 100 mm Hg: 3.04 (1.24-7.44), P = 0.02, and winter time: 1.84 (1.06-3.21), P = 0.03. Of the 87 hypothermic patients who had repeat temperatures recorded in the Emergency Department, 77 (88.51%) patients had a temperature greater than the recorded arrival temperature. There was no change in recorded temperature for four (4.60%) patients, whereas six (6.90%) patients were colder at Emergency Department discharge.

CONCLUSION

Seriously injured patients with accidental hypothermia have a higher mortality independent of measured risk factors. For patients with multiple injuries a coordinated effort by paramedics, nurses and doctors is required to focus efforts toward early resolution of hypothermia aiming to achieve a temperature >35 °C.