Clinical Interventions Account for Scene Time in a Helicopter Emergency Medical Service in South Africa

A Retrospective Geospatial Simulation Study of Helicopter Emergency Medical Services' Potential Time Benefit Over Ground Ambulance Transport in Northern South Africa

OBJECTIVE

One of the most important benefits of helicopter emergency medical services (HEMS) is a time benefit, either through expedited access to the casualty or a reduction in the transport time to definitive care. However, HEMS utilization does not come without risk to the public and crew or at an insignificant cost. Cost is an essential consideration for health policy decisions, especially in low- to middle-income countries, such as South Africa. The aim of this study was to determine whether there is a time benefit of HEMS dispatch in South Africa compared with simulated driving time. A secondary aim was to determine the distance from the incident site to the hospital at which a time benefit can be guaranteed.

METHODS

A retrospective study was undertaken by comparing the prehospital times of patients who underwent HEMS transportation with simulated ground emergency medical services (GEMS) transportation times. Handwritten patient records of actual flights were reviewed and analyzed. The actual flight times recorded were used to calculate the helicopter transport time, activation to scene time, scene time, and scene to hospital time. Times were assigned based on a nonsimultaneous dispatch model, as is used in South Africa. For each helicopter mission, Google Maps (Google Inc, Mountain View, CA) was used to simulate the fastest ground route from the same location of the incident to the same receiving hospital corrected for typical traffic trends. The actual HEMS and simulated GEMS times were compared using the paired t-test. Linear regression analysis was performed to determine a minimum driving distance at which HEMS provides a time benefit.

RESULTS

A total of 118 HEMS transports were analyzed, the majority of which were trauma related (n = 115, 97%). HEMS transport resulted in a mean time deficit of -15 minutes (95% confidence interval, -18 to -11; P < .05) compared with simulated GEMS drive times. After regression, HEMS transport provides a time benefit at a driving distance greater than 119 km.

CONCLUSION

The current study demonstrated that there was rarely a time benefit for actual primary emergency responses when HEMS was used compared with simulated driving time of GEMS transport. Using a nonsimultaneous dispatch model, a time benefit only occurs when the driving distance from the incident site to the hospital is greater than 119 km. There is an urgent need to critically evaluate HEMS utilization in the South African context.

The Effect of Prehospital Clinical Trial-Related Procedures on Scene Interval, Cognitive Load, and Error: A Randomized Simulation Study

INTRODUCTION

Globally, very few settings have undertaken prehospital randomized controlled trials. Given this lack of experience, there is a risk that such trials in these settings may result in protocol deviations, increased prehospital intervals, and increased cognitive load, leading to error. Ultimately, this may affect patient safety and mortality. The aim of this study was to assess the effect of trial-related procedures on simulated scene interval, self-reported cognitive load, medical errors, and time to action.

METHODS

This was a prospective simulation study. Using a cross-over design, ten teams of prehospital clinicians were allocated to three separate simulation arms in a random order. Simulations were: (1) Eligibility assessment and administration of freeze-dried plasma (FDP) and a hemoglobin-based oxygen carrier (HBOC), (2) Eligibility assessment and administration of HBOC, (3) Eligibility assessment and standard care. All simulations also required clinical management of hemorrhagic shock. Simulated scene interval, error rates, cognitive load (measured by NASA Task Load Index), and competency in clinical care (assessed using the Simulation Assessment Tool Limiting Assessment Bias (SATLAB)) were measured. Mean differences between simulations with and without trial-related procedures were sought using one-way ANOVA or Kruskal-Wallis test. A p-value of <0.05 within the 95% confidence interval was considered significant.

RESULTS

Thirty simulations were undertaken, representing our powered sample size. The mean scene intervals were 00:16:56 for Simulation 1 (FDP and HBOC), 00:17:22 for Simulation 2 (HBOC only), and 00:14:24 for Simulation 3 (standard care). Scene interval did not differ between the groups (p = 0.27). There were also no significant differences in error rates (p = 0.28) or cognitive load (p = 0.67) between the simulation groups. There was no correlation between cognitive load and error rates (r = 0.15, p = 0.42). Competency was achieved in all the assessment criteria for all simulation groups.

CONCLUSION

In a simulated environment, eligibility screening, performance of trial-related procedures, and clinical management of patients with hemorrhagic shock can be completed competently by prehospital advanced life support clinicians without delaying transport or emergency care. Future prehospital clinical trials may use a similar approach to help ensure graded and cautious implementation of clinical trial procedures into prehospital emergency care systems.

A 12-month retrospective descriptive analysis of a single helicopter emergency medical service operator in four South African provinces

Introduction

Helicopter Emergency Medical Services (HEMS) is integrated into modern emergency medical services because of its suggested mortality benefit in certain patient populations, it is an expensive resource and appropriate use/feasibility in low- to middle income countries (LMIC) is highly debated. To maximise benefit, correct patient selection in HEMS is paramount. To achieve this, current practices first need to be described. The study aims to describe a population of patients utilising HEMS in South Africa, in terms of flight data, patient demographics, provisional diagnosis, as well as clinical characteristics and interventions.

Methods

A retrospective flight- and patient-chart review were conducted, extracting clinical and mission data of a single aeromedical operator in South Africa, over a 12-month period (July 2017 - June 2018) in Gauteng, Free State, Mpumalanga and North-West provinces.

Results

A total of 916 cases were included (203 primary cases, 713 interfacility transport (IFT) cases). Most patients transported were male (n=548, 59.8%) and suffered blunt trauma (n=379, 41.4%). Medical pathology (n=247, 27%) and neonatal transfers (n=184, 20.1%) follows. Flights occurred mainly in daylight hours (n=729, 79.6%) with median mission times of 1-hour 53 minutes (primary missions), and 3 hours 10 minutes (IFT missions). Median on-scene times were 26 minutes (primary missions) and 55 minutes (IFT missions). Almost half were transported with an endotracheal tube (n=428, 46.7%), with a large number receiving no respiratory support (n=414, 45.2%). No patients received fibrinolysis, defibrillation, cardioversion or cardiac pacing. Intravenous fluid therapy (n=867, 94.7%) was almost universal, with common administration of sedation (n=430, 46.9%) and analgesia (n=329, 35.9%).

Conclusion

Apart from the lack of universal call-out criteria and response to the high burden of trauma, HEMS seem to fulfil an important critical care transport role. It seems that cardiac pathologies are under-represented in this study and might have an important implication for crew training requirements.

Prehospital Emergency Care in Low- and Middle-Income Countries: A Systematic Review

BACKGROUND

An under-developed and fragmented prehospital Emergency Medical Services (EMS) system is a major obstacle to the timely care of emergency patients. Insufficient emphasis on prehospital emergency systems in low- and middle-income countries (LMICs) currently causes a substantial number of avoidable deaths from time-sensitive illnesses, highlighting a critical need for improved prehospital emergency care systems. Therefore, this systematic review aimed to assess the prehospital emergency care services across LMICs.

METHODS

This systematic review used four electronic databases, namely: PubMed/MEDLINE, CINAHL, EMBASE, and SCOPUS, to search for published reports on prehospital emergency medical care in LMICs. Only peer-reviewed studies published in English language from January 1, 2010 through November 1, 2022 were included in the review. The Newcastle-Ottawa Scale (NOS) and Critical Appraisal Skills Programme (CASP) checklist were used to assess the methodological quality of the included studies. Further, the protocol of this systematic review has been registered on the International Prospective Register of Systematic Reviews (PROSPERO) database (Ref: CRD42022371936) and has been conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Of the 4,909 identified studies, a total of 87 studies met the inclusion criteria and were therefore included in the review. Prehospital emergency care structure, transport care, prehospital times, health outcomes, quality of information exchange, and patient satisfaction were the most reported outcomes in the considered studies.

CONCLUSIONS

The prehospital care system in LMICs is fragmented and uncoordinated, lacking trained medical personnel and first responders, inadequate basic materials, and substandard infrastructure.

A retrospective descriptive analysis of non-physician-performed prehospital endotracheal intubation practices and performance in South Africa

Introduction

Prehospital advanced airway management, including endotracheal intubation (ETI), is one of the most commonly performed advanced life support skills. In South Africa, prehospital ETI is performed by non-physician prehospital providers. This practice has recently come under scrutiny due to lower first pass (FPS) and overall success rates, a high incidence of adverse events (AEs), and limited evidence regarding the impact of ETI on mortality. The aim of this study was to describe non-physician ETI in a South African national sample in terms of patient demographics, indications for intubation, means of intubation and success rates. A secondary aim was to determine what factors were predictive of first pass success.

Methods

This study was a retrospective chart review of prehospital ETIs performed by non-physician prehospital providers, between 01 January 2017 and 31 December 2017. Two national private Emergency Medical Services (EMS) and one provincial public EMS were sampled. Data were analysed descriptively and summarised. Logistic regression was performed to evaluate factors that affect the likelihood of FPS.

Results

A total of 926 cases were included. The majority of cases were adults (n = 781, 84.3%) and male (n = 553, 57.6%). The most common pathologies requiring emergency treatment were head injury, including traumatic brain injury (n = 328, 35.4%), followed by cardiac arrest (n = 204, 22.0%). The mean time on scene was 46 minutes (SD = 28.3). The most cited indication for intubation was decreased level of consciousness (n = 515, 55.6%), followed by cardiac arrest (n = 242, 26.9%) and ineffective ventilation (n = 96, 10.4%). Rapid sequence intubation (RSI, n = 344, 37.2%) was the most common approach. The FPS rate was 75.3%, with an overall success rate of 95.7%. Intubation failed in 33 (3.6%) patients. The need for ventilation was inversely associated with FPS (OR = 0.42, 95% CI: 0.20–0.88, p = 0.02); while deep sedation (OR = 0.56, 95% CI: 0.36–0.88, p = 0.13) and no drugs (OR = 0.47, 95% CI: 0.25–0.90, p = 0.02) compared to RSI was less likely to result in FPS. Increased scene time (OR = 0.99, 95% CI: 0.985–0.997, p < 0.01) was inversely associated FPS.

Conclusion

This is one of the first and largest studies evaluating prehospital ETI in Africa. In this sample of ground-based EMS non-physician ETI, we found success rates similar to those reported in the literature. More research is needed to determine AE rates and the impact of ETI on patient outcome. There is an urgent need to standardise prehospital ETI reporting in South Africa to facilitate future research.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12873-022-00688-4.

Helicopter Emergency Medical Services in Trauma Does Not Influence Mortality in South Africa

OBJECTIVE

Sub-Saharan Africa carries a large trauma burden. Helicopter emergency medical services (HEMS) have been suggested to reduce prehospital time and mortality. It is not clear whether HEMS infers a mortality benefit over ground transport in South Africa. This study aimed to determine whether HEMS improved 30-day mortality over ground emergency medical services (GEMS).

METHODS

A retrospective, case-control study was undertaken for major trauma patients transported to a private trauma center in Johannesburg. A 1-year cohort of HEMS patients was extracted and matched to GEMS patients based on mechanism, injury severity or percentage of the total body surface area burned, age, sex, and comorbidities. The odds ratio (OR) for 30-day mortality was calculated to determine the risk of death.

RESULTS

A total of 822 cases (HEMS: 272 [33%], GEMS: 550 [67%]) were reviewed. We included 410 patients in the matched cohort with equal distribution between transportation modes. The OR for mortality in the total cohort was 2.69 (95% confidence interval, 1.6-4.6; P = .003) for HEMS patients, whereas in the matched cohort the OR was 1.35 (95% confidence interval, 0.5-3.4; P = .503) for patients transported by HEMS.

CONCLUSION

In a matched cohort of major trauma patients, HEMS does not seem to improve mortality over GEMS. These results might reflect the South African HEMS dispatch model.