Herts Air Ambulance Research Articles

Cardiorespiratory consequences of attenuated fentanyl and augmented rocuronium dosing during protocolised prehospital emergency anaesthesia at a regional air ambulance service: a retrospective study

BackgroundPre-Hospital Emergency Anaesthesia (PHEA) has undergone significant developments since its inception. However, optimal drug dosing remains a challenge for both medical and trauma patients. Many prehospital teams have adopted a drug regimen of 3 mcg/kg fentanyl, 2 mg/kg ketamine and 1 mg/kg rocuronium (‘3:2:1’). At Essex and Herts Air Ambulance Trust (EHAAT) a new standard dosing regimen was introduced in August 2021: 1 mcg/kg fentanyl, 2 mg/kg ketamine and 2 mg/kg rocuronium (up to a maximum dose of 150 mg) (‘1:2:2’). The aim of this study was to evaluate the cardiorespiratory consequences of a new attenuated fentanyl and augmented rocuronium dosing regimen.MethodsA retrospective study was conducted at EHAAT as a service evaluation. Anonymized records were reviewed from an electronic database to compare the original (‘3:2:1’) drug dosing regimen (December 2019-July 2021) and the new (‘1:2:2’) dosing regimen (September 2021-May 2023). The primary outcome was the incidence of absolute hypotension within ten minutes of induction. Secondary outcomes included immediate hypertension, immediate hypoxia and first pass success (FPS) rates.ResultsFollowing exclusions (n = 121), 720 PHEA cases were analysed (360 new vs. 360 original, no statistically significant difference in demographics). There was no difference in the rate of absolute hypotension (24.4% ‘1:2:2’ v 23.8% ‘3:2:1’, p = 0.93). In trauma patients, there was an increased first pass success (FPS) rate with the new regimen (95.1% v 86.5%, p = 0.01) and a reduced incidence of immediate hypoxia (7.9% v 14.8%, p = 0.05). There was no increase in immediate hypertensive episodes (22.7% vs. 24.2%, p = 0.73). No safety concerns were identified.ConclusionAn attenuated fentanyl and augmented rocuronium dosing regimen showed no difference in absolute hypotensive episodes in a mixed cohort of medical and trauma patients. In trauma patients, the new regimen was associated with an increased FPS rate and reduced episodes of immediate hypoxia. Further research is required to understand the impact of such drug dosing in the most critically ill and injured subpopulation.

A Psychological Resilience Briefing Intervention for Helicopter Emergency Medical Service Observers

ObjectiveHelicopter emergency medical services (HEMS) observers may be at risk of negative psychological effects associated with exposure to traumatic events during shifts. This article describes a quality improvement project for HEMS observers at Essex & Herts Air Ambulance. MethodsA psychological resilience briefing intervention (PRBi) was developed and delivered during induction training with 60 HEMS observers. The PRBi aimed to raise awareness of traumatic events that observers may experience and provided basic education on 5 domains, including likely forms of trauma exposure, possible psychological reactions, advice on coping strategies and supporting colleagues, and resources that they could use if required. The intervention was intended to bolster resilience and reduce posttraumatic stress disorder symptoms, and to encourage adaptive coping styles in observers. ResultsObservers learned from and valued the PRBi; statistically significant increases were observed in awareness of the 5 domains from pre- to post-delivery, and free-text responses cited a variety of benefits to the observers. There was no indication that the PRBi caused harm. ConclusionThe PRBi has now been included in the routine induction of observers at Essex & Herts Air Ambulance and has the potential to be repurposed for use in other settings, including medical schools.

Cardiovascular complications of prehospital emergency anaesthesia in patients with return of spontaneous circulation following medical cardiac arrest: a retrospective comparison of ketamine-based and midazolam-based induction protocols

BackgroundHypotension following intubation and return of spontaneous circulation (ROSC) after cardiac arrest is associated with poorer patient outcomes. In patients with a sustained ROSC requiring emergency anaesthesia, there is limited...

Helicopter Emergency Medical Services Out-of-Hospital Cardiac Arrests During the Initial COVID-19 Lockdown Versus Nonpandemic: A Comparison

ObjectiveCOVID-19 may have contributed to an excess of out-of-hospital cardiac arrests (OOHCAs). This observational study identified changes in OOHCA epidemiology pre– and post–COVID-19 lockdown in a single UK helicopter emergency medical service (HEMS). MethodsA retrospective, single-center (Essex & Herts Air Ambulance), observational study was undertaken with anonymized OOHCA data (demographics, etiology, and outcomes) from March 23, 2020, to June 23, 2020, and comparative data from March 23, 2019, to June 23, 2019. Supplementary data (total OOHCAs and patient outcomes) were provided by the East of England Ambulance Service National Health Service Trust. Data were analyzed using the Mann-Whitney U test and chi-square test; P < .05 was statistically significant.Results: Of the HEMS activations during national lockdown, 33.6% were for OOHCAs compared with 25.8% during the reference time frame. The frequency of young and female OOHCAs demonstrated a statistically significant increase. Statistically significant variations in medical etiology and initial cardiac rhythm were identified. ConclusionDuring the initial UK-wide lockdown, the OOHCA characteristics attended by 1 HEMS team were altered. The changes seen may be due to the pathophysiology of COVID-19 or an alteration in dispatch due to the demand placed on the wider ambulance service; this may require further consideration for any future lockdowns or pandemics.

Consensus on research priorities for Essex & Herts Air Ambulance: a Delphi study

BackgroundConsensus methods such as the Delphi technique have been used widely for research priority setting in health care. Within pre-hospital emergency medicine, such approaches have helped to establish national and international research priorities. However, in a dynamic field such as pre-hospital critical care, it is necessary to regularly review the continued relevance of findings. Further, considering the variability between pre-hospital critical care providers, it is also important to determine priorities at the local level. Essex & Herts Air Ambulance (EHAAT) sought to develop a five-year research strategy that aligns with their clinical work streams and organisational priorities.MethodsAll staff and Trustees were invited to participate in an online Delphi study with three Rounds. The Delphi was administered via email and Online Surveys software. The first Round invited participants to submit up to five research questions that they felt were of greatest importance to EHAAT to advance the care provided to patients. In Round 2, participants were asked to rate the importance of questions from Round 1, while Round 3 required participants to rank questions that were prioritised in Round 2 in order of importance.Results22 participants submitted a total of 86 research questions in Round 1, which were reduced to 69 questions following deduplication and refinement. 11 participants rated the importance of the questions in Round 2, resulting in 14 questions being taken forward to Round 3. Following the ranking exercise in Round 3, completed by 12 participants, a top five research priorities were identified. The question deemed most important was “How does a pre-hospital doctor-paramedic team affect the outcome of patients with severe head injuries?”.ConclusionsThe top five research priorities identified through the Delphi process will inform EHAAT’s research strategy. Findings suggest that there is still work to be done in addressing research priorities described in previous literature.

Scoping the Demand for Night Operation of Essex & Herts Air Ambulance: A Prospective Observational Study

ObjectiveHelicopter emergency medical services play an important role in the prehospital care of critically ill and injured patients, providing enhanced interventions and direct transfer to specialist centers. Essex & Herts Air Ambulance (EHAAT) delivers prehospital critical care to patients in Essex, Hertfordshire, and the surrounding areas. Historically, EHAAT's resources have not operated during the night. This study aimed to ascertain demand for prehospital critical care in Essex and Hertfordshire during night hours. MethodsA prospective observational design was used. Data were collected by 11 critical care paramedics during night shifts on a critical care desk using an online survey. Details were recorded for incidents in Essex and Hertfordshire between 21:00 and 07:00 deemed appropriate for a prehospital critical care response. ResultsA total of 108 incidents were recorded across 52 nights, equating to an average of 2.08 incidents per night. For 52 incidents, there was no critical care resource available to attend. The majority of incidents fell in closer proximity to EHAAT's North Weald base than its Earls Colne base. ConclusionThe findings suggest a potential need for prehospital critical care during night hours in Essex and Hertfordshire and support the operation of a resource from EHAAT's North Weald base.

Four years of pre-hospital simple thoracostomy performed by a physician-paramedic helicopter emergency medical service team: A description and review of practice

Background Essex and Herts Air Ambulance Trust operate doctor-paramedic pre-hospital care teams. Simple thoracostomy is performed if an intubated patient requires pleural decompression. Reports of the use of this technique are uncommon in the literature. This study describes the use of pre-hospital thoracostomy over four years. Pre-hospital complications and effect on oxygen saturations were also noted. Methods A retrospective database review of all missions that occurred between 1 April 2010 and 31 March 2014. All patients undergoing this procedure were included. Results A total of 126 patients were identified. In 110 (87%) of the total number of patients, the procedure was bilateral making the total number of thoracostomies performed 236. The mechanism of injury was blunt trauma in 115 (91%) and penetrating trauma in 11 patients (9%). The primary indication was traumatic cardiac arrest or peri-arrest in 51 patients (40%), high risk of pneumothorax in a ventilated patient in 45 patients (36%), pneumothorax diagnosed prior to delivery of anaesthesia in 17 patients (13%), and unexplained hypoxia in a ventilated patient in 13 patients (10%). The mean pulse oximetry measurement at the time of arrival was 91.8% and 97.2% at the time of handover ( p=0.003). No immediate complications were recorded on the database. Conclusion We have described the regular use of the technique of simple thoracostomy in trauma patients attended by our air ambulance service. It is the largest case series to date of simple thoracostomy being used in the context of pre-hospital chest trauma.

Ketamine for procedural sedation by a doctor-paramedic prehospital care team

Ketamine is a widely used drug that, depending on the dose administered, may be used as an analgesic or as a sedative or anaesthetic agent. A number of features make it attractive for prehospital use. At Essex and Herts Air Ambulance Trust, as with other services and under the guidance of a standard operating procedure, ketamine is used for both procedural sedation and as an anaesthetic agent for rapid sequence intubation. Guidelines exist that define levels of sedation and detail minimum standards of monitoring and personnel required for each level. We conducted a retrospective review from 4 years of our mission database for patients who had received ketamine for procedural sedation from the doctor-paramedic helicopter emergency medical service team. Other data relevant to the patient or the mission were also collected. A total of 212 cases of ketamine used for procedural sedation were identified. In all, 111 (52.4%) were for fracture manipulations and 52 (24.5%) were to facilitate extrication. An overall 12.7% of patients were paediatric (less than 18 years) and 160 (75.5%) were male. The helicopter emergency medical service team was with the patient for a mean of 24.4 min after the 999 call and spent a mean of 44.6 min on scene before departing for the hospital, which, in 75% of cases, was by means of a helicopter. A full set of monitoring was documented as having been used in 59 (27.8%) cases. We describe the use of ketamine over a 4-year period for prehospital procedural sedation. Minimum standards for patient monitoring were documented in only around a quarter of cases.

Essex and Herts Air Ambulance: a focused case series for pre-hospital practice

Due to the relative infrequency of major trauma in the paediatric population, along with the presence of family members during the resuscitation, management of trauma in this age group can be both emotive and highly challenging. Through comprehensive assessment, targeted resuscitation and considered triage to an appropriate paediatric trauma facility, pre-hospital care clinicians can help to improve outcomes in the paediatric trauma patient ( Simpson et al, 2012 ; Nystrup et al, 2015 ). This article aims to provide a structured, evidence-based approach to the assessment and management of the injured child in the pre-hospital setting. We report the case of a 10-year old female involved in a pedestrian versus van road traffic collision (RTC). The principles of systematic assessment and holistic management of the paediatric trauma patient are discussed. We also discuss where an extended care service such as a Helicopter Emergency Medical Service may be of assistance.

Survival to Discharge After Cardiac Arrest Attended by a Doctor–Paramedic Helicopter Emergency Medical Service: An Utstein-style Multiservice Review of 1085 Activations

BackgroundThe presentation of outcomes after cardiac arrest presented by emergency medical service and in-hospital teams in the Utstein style allows for comparative analysis of populations and systems. Essex and Herts Air Ambulance Trust (EHAAT) and the East Anglian Air Ambulance (EAAA) are doctor-plus-paramedic prehospital care teams that respond to a large number of medical cardiac arrests. ObjectiveTo report the outcomes of medical cardiac arrests according to the Utstein style. MethodsRetrospective database analysis and hospital follow-up of all cardiac arrests attended by either service over a 31-month period. Traumatic cardiac arrests were excluded. Primary outcome: survival and cerebral performance category at discharge from the hospital. ResultsThere were 429 patients attended by the two services; 193 patients achieved return of spontaneous circulation, which was sustained at the time of handover to the hospital team. Of 140 patients for whom complete follow-up was available, the overall survival rate was 50.7%, 86% of whom had a Cerebral Performance Category of 1 or 2. The overall survival-to-discharge rate for all patients attended was 11.7%. ConclusionBenchmarking of performance is essential to understand reasons for variability, and to allow individual systems to reflect on their own practices. We have described 31 months of data that pertain to medical cardiac arrest cases attended by our services and demonstrated a comparable survival rate to discharge with good neurological outcome.

Essex and Herts Air Ambulance: a focused case series for pre-hospital practice

Pelvic fractures cause significant mortality and morbidity in major trauma patients and contribute to early deaths both pre-hospital and in-hospital. Traditional teaching that few pre-hospital interventions benefit patients with major pelvic fractures has been challenged in recent years and a number of key early interventions are now seeing many such patients survive to reach a surgeon or interventional radiologist for definitive care. We outline the case of a 38-year-old male who sustained a crush injury resulting in a severe lateral compression fracture of his pelvis with associated haemodynamic instability. Fundamental principles of pre-hospital pelvic fracture management are explained including core techniques of patient handling, splinting and packaging along with analgesic strategies and triage principles. Novel theories and interventions for haemostasis are described. The additional care that can be provided by an enhanced care team is also discussed.

Essex and Herts Air Ambulance: a focused case series for pre-hospital practice Case 3: a femoral shaft fracture

The femur is the longest bone in the human body and is surrounded by a dense and vascular cylindrical sheath of soft tissue. Femoral fractures are often the result of high-energy traumatic injuries and result in pain, blood loss and immobility of the affected leg. General principles of acute management include analgesia, assessment of the patient for associated injuries and restoration of anatomical alignment of the leg. Assessment and documentation of the neurovascular function in the foot distal to the fracture is essential. Haemorrhage from a femoral fracture can be extensive, even more so if the fracture is open. Control of further blood loss and attention to the patient's cardiovascular status is mandatory. We report the case of a 23-year-old woman who was involved in a pedestrian-versus-car incident and sustained an isolated right femoral fracture. Scene and patient assessment are discussed along with early management principles including analgesia and traction. We also discuss where an extended care service such as a Helicopter Emergency Medical Service (HEMS) may be of assistance

Essex and Herts Air Ambulance: a focused case series for pre-hospital practice Case 2: tension pneumothorax

A tension pneumothorax is an important reversible cause of deterioration in the multiply-injured patient, but it is not always easy to make the diagnosis. Features that indicate the development of a tension pneumothorax can be subtle in the spontaneously breathing patient. The ‘classical’ features may not all be present and in addition, the clinical signs of tension may develop over time with increasing patient compromise. This is a life-threatening situation, which requires relief in order to save the patient's life. A tension pneumothorax can be managed in one of three ways: needle decompression, insertion of an intercostal chest drain or by open thoracostomy. Needle decompression can be performed quickly and safely by paramedic crews using well-established techniques in both the conscious and unconscious patient. We describe a case of a 55-year-old male who was ejected from his motorcycle at high speed. He was conscious with a Glasgow Coma Score (GCS) of 15 and complaining of difficulty breathing. In contrast to the often quoted classical features of a tension pneumothorax, we review the more common clinical findings in tension pneumothoraces as illustrated in this case study. We aim to show that the diagnosis can be reached by careful history taking, examination, and attention to patient physiology. The case study also shows that a tension pneumothorax can be a dynamic developing situation in which patient compromise develops over time. We highlight that much can be done in the pre-hospital phase to treat such a patient while expediting transfer to hospital. We review the pre-hospital management of a tension pneumothorax and also describe our procedure for pre-hospital chest drain insertion in the context of effective teamwork between a paramedic road crew and an attending helicopter emergency medical service (HEMS).

Essex and Herts Air Ambulance: a focused case series for pre-hospital practice

Burns and scalds are relatively common in children and can be distressing for all involved. General principles of early management are to limit the progression of the burn through cooling, and to manage pain in order to perform a thorough assessment and improve the patient's experience. Assessment of burns includes an estimation of body surface area involved, an appreciation of the depth of burn, and the consideration of ‘special areas’ affected. A number of tools and guides exist that help standardise this assessment. However, it is impossible to truly know the size and extent of the burn during the first contact meeting in the pre-hospital environment as a burn matures and develops over the course of 72 hours. Treatment regimes are focused upon improving blood flow to the area of stasis, a fragile circumferential area between the zone of coagulation, in which the tissue is already unsalvageable, and the zone of hyperaemia, where blood flow to the surrounding tissues in increased. We report the case of a 2-year-old boy who sustained a scald to the abdomen after pulling over a freshly made cup of tea. We describe an approach to burns in children, in collaboration with parents. This case highlights the need for early adequate analgesia, thorough assessment, and triage to the correct hospital where the patient's injury can be appropriately managed. We also highlight areas in which an extended care service such as a helicopter emergency medical service (HEMS) team can help, particularly in terms of supplementary analgesia and transfer to specialist units.