Pre-hospital emergency anaesthesia in the United Kingdom: an observational cohort study

Haemodynamic response to pre-hospital emergency anaesthesia in trauma patients within an urban helicopter emergency medical service

PURPOSE

Pre-hospital emergency anaesthesia is routinely used in the care of severely injured patients by pre-hospital critical care services. Anaesthesia, intubation, and positive pressure ventilation may lead to haemodynamic instability. The aim of this study was to identify the frequency of new-onset haemodynamic instability after induction in trauma patients with a standardised drug regime.

METHODS

A retrospective database analysis was undertaken of all adult patients treated by a physician-led urban pre-hospital care service over a 6-year period. The primary outcome measure was the frequency of new haemodynamic instability following pre-hospital emergency anaesthesia. The association of patient characteristics and drug regimes with new haemodynamic instability was also analysed.

RESULTS

A total of 1624 patients were included. New haemodynamic instability occurred in 231 patients (17.4%). Patients where a full-dose regime was administered were less likely to experience new haemodynamic instability than those who received a modified dose regime (9.7% vs 24.8%, p < 0.001). The use of modified drug regimes became more common over the study period (p < 0.001) but there was no change in the rates of pre-existing (p = 0.22), peri-/post-anaesthetic (p = 0.36), or new haemodynamic instability (p = 0.32).

CONCLUSION

New haemodynamic instability within the first 30 min following pre-hospital emergency anaesthesia in trauma patients is common despite reduction of sedative drug doses to minimise their haemodynamic impact. It is important to identify non-drug factors that may improve cardiovascular stability in this group to optimise the care received by these patients.

Induction of pre-hospital emergency anaesthesia i-PHEA: a national survey of UK HEMS practice

BACKGROUND

Pre-hospital emergency anaesthesia is a critical intervention undertaken by helicopter emergency medical teams. Previous studies informed current practice for induction regimes, using a standardized approach of fentanyl, ketamine and rocuronium. There may be a trend towards post-induction hypotension attributed to the induction regime used. Several new combinations of fentanyl, ketamine and rocuronium are emerging in clinical practice. There is currently no consensus on what induction regimes should be used.

METHODS

A semi-structured survey was distributed to the medical leads of all UK air ambulance organisations between December 2022 and February 2023. Responses that were returned within the study period were included. Exclusions included missing data, declined participation and failure to return the survey within the data collection period. The survey sought to establish provision of pre-hospital emergency anaesthesia and current induction regimes for stable, unstable and post-cardiac arrest patients. Data was extracted from Microsoft Forms into Excel. Descriptive statistics were used to analyse survey response rate, provision of PHEA and induction regimes. The survey was endorsed by the National HEMS Research and Audit Forum.

RESULTS

19 air ambulance organisations responded (response rate 86%). The majority of organisations provide over 100 pre-hospital emergency anaesthetics per annum (79%, n = 15/19). A standard combination of fentanyl, ketamine and rocuronium is used as a primary induction regime in haemodynamically stable patients by 52% of services (n = 10/19). In haemodynamically compromised patients, fentanyl was omitted or pracititioner choice emphasized by 79% of services (n = 15/19). There was variability in the dose of rocuronium from 1 mg/kg to 2 mg/kg throughout services.

CONCLUSION

There is variability in the approach to pre-hospital emergency anaesthesia. There is a growing dataset that would enable development of a registry to better understand induction regimes and the impact on patient physiology. Organisations are increasingly adopting a patient centered, practitioner choice model towards induction of anaesthesia.

Advanced diagnostic and therapeutic techniques for anaesthetists in thoracic trauma: an evidence-based review

Anaesthetists play an important role in the evaluation and treatment of patients with signs of thoracic trauma. Anaesthesia involvement can provide valuable input using both advanced diagnostic and therapeutic interventions. Commonly performed interventions may be complicated in this setting including airway management, damage control resuscitation, and acute pain management. Anaesthetists must consider additional factors including airway injuries, vascular injuries, and coagulopathy when treating this population. This evidence-based review discusses traumatic thoracic injuries with a focus on new interventions and modern anaesthesia techniques. This review further serves to support the early involvement of anaesthetists in the emergency department and other areas where they can provide value to the trauma care pathway.

Protocol for a systematic review on effective patient positioning for rapid sequence intubation

INTRODUCTION

Rapid sequence intubation (RSI) is an advanced airway technique to perform endotracheal intubation in patients at high risk of aspiration. Although RSI is recognised as a life-saving technique and performed by many physicians in various settings (emergency departments, intensive care units), there is still a lack of consensus on various features of the procedure, most notably patient positioning. Previously, experts have commented on the unique drawbacks and benefits of various positions and studies have been published comparing patient positions and how it can affect endotracheal intubation in the context of RSI. The purpose of this systematic review is to compile the existing evidence to understand and compare how different patient positions can potentially affect the success of RSI.

METHODS AND ANALYSIS

We will use MEDLINE, EMBASE and the Cochrane Library to source studies from 1946 to 2021 that evaluate the impact of patient positioning on endotracheal intubation in the context of RSI. We will include randomised control trials, case-control studies, prospective/retrospective cohort studies and mannequin simulation studies for consideration in this systematic review. Subsequently, we will generate a Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagram to display how we selected our final studies for inclusion in the review. Two independent reviewers will complete the study screening, selection and extraction, with a third reviewer available to address any conflicts. The reviewers will extract this data in accordance with our outcomes of interest and display it in a table format to highlight patient-relevant outcomes and difficulty airway management outcomes. We will use the Risk of Bias tool and the Newcastle-Ottawa Scale to assess included studies for bias.

ETHICS AND DISSEMINATION

This systematic review does not require ethics approval, as all patient-centred data will be reported from published studies.

PROSPERO REGISTRATION NUMBER

CRD42022289773.

Pre-hospital emergency anaesthesia in trauma patients: An observational study from a state-wide Australian pre-hospital and retrieval service

OBJECTIVE

To assess the performance of an Australian pre-hospital and retrieval medicine (PHRM) service against the National Institute for Health and Care Excellence (NICE) standard which recommends that pre-hospital emergency anaesthesia (PHEA) in trauma patients should be conducted within 45-min of first contact with emergency services.

METHODS

Retrospective observational study of all adult trauma patients in which PHEA was conducted by the PHRM service covering a 5-year period from January 2015 to December 2019.

RESULTS

Over the 5-year study period, 1509 (22%) of the PHRM service workload comprised primary retrievals from scene. Most 1346 (89%) of these cases had a primary diagnosis of trauma. Of these we have complete data for 328 of the 337 cases requiring a PHEA and 121 (37%) patients received this within the recommended 45-min time frame. The service attended in rapid response vehicles (n = 160, 49%), rotary wing (n = 151, 46%) and fixed wing (n = 17, 5%) transport modalities. For a service covering 983 482 km² , the median distance travelled to patients was 35 (16-71) km and the median time to PHEA was 54 (38-80) min.

CONCLUSIONS

In a cohort of 337 patients treated by a dedicated PHRM service in South Australia, the median time to PHEA was 54 (38-80) min with only 37% of patients receiving PHEA within 45 min from the activation of the team. Despite differing patient demographics, the percentage of patients receiving PHEA within the recommended time frame was greater than a similar cohort from the UK. However, both data sets still fall short of recommended targets.

Rapid sequence induction: where did the consensus go?

Background

Rapid Sequence Induction (RSI) was introduced to minimise the risk of aspiration of gastric contents during emergency tracheal intubation. It consisted of induction with the use of thiopentone and suxamethonium with the application of cricoid pressure.

This narrative review describes how traditional RSI has been modified in the UK and elsewhere, aiming to deliver safe and effective emergency anaesthesia outside the operating room environment. Most of the key aspects of traditional RSI – training, technique, drugs and equipment have been challenged and often significantly changed since the procedure was first described. Alterations have been made to improve the safety and quality of the intervention while retaining the principles of rapidly securing a definitive airway and avoiding gastric aspiration. RSI is no longer achieved by an anaesthetist alone and can be delivered safely in a variety of settings, including in the pre-hospital environment.

Conclusion

The conduct of RSI in current emergency practice is far removed from the original descriptions of the procedure. Despite this, the principles – rapid delivery of a definitive airway and avoiding aspiration, are still highly relevant and the indications for RSI remain relatively unchanged.

Geo-temporal provision of pre-hospital emergency anaesthesia by UK Helicopter Emergency Medical Services: an observational cohort study

BACKGROUND

Pre-hospital emergency anaesthesia (PHEA) is frequently required for injured patients. National Institute for Health and Care Excellence (NICE) quality standards state that PHEA should be delivered within 45 min of an emergency call. We investigated whether there is geo-temporal variation in service provision to the UK population.

METHODS

We retrospectivly audited the time of day when PHEA is provided by UK Helicopter Emergency Medical Services (HEMS), by recording PHEA provision on a randomly selected week and weekend day in 2018. Pre-hospital emergency anaesthesia in the United Kingdom: an observational cohort study retrospectively assessed the time from emergency call to pre-hospital emergency anaesthesia delivery by HEMS during a 1 yr period from April 2017 to March 2018. The population coverage likely to receive pre-hospital emergency anaesthesia in accord with NICE guidelines was estimated by integrating population data with the median time to PHEA, hours of service provision, geographic location, and transport modality.

RESULTS

On a weekday 20 HEMS units (comprising from four to 31 enhanced care teams) were estimated to be able to meet NICE guidelines for delivery of PHEA to a poulation of 6.6-35.2 million individuals (at times of minimum and maximal staffing, respectively). At the weekend, 17 HEMS units (comprising from 5 to 28 enhanced care teams) were estimated to be able to meet NICE guidelines for PHEA deliveryto a population of 6.8-34.1 million individuals (minimum and maximal staffing, respectively).

CONCLUSIONS

There is marked geo-temporal variation in the ability of HEMS organisations to deliver pre-hospital emergency anaesthesia in the UK.