New heights for HEMS critical care
Helicopter emergency medical services are at the forefront of pre-hospital care, delivering lifesaving interventions and providing rapid transport to hospitals. Experts share with Lauren Haigh the latest updates in treatment, training and equipment
Helicopter emergency medical services (HEMS) teams across the globe are united by a shared drive to optimize patient outcomes. The bottom line is that HEMS saves lives, providing rapid response and critical care to those in desperate need. A key advantage is the ability to respond swiftly to emergency situations and provide quick transportation. “Frequently, the best treatment HEMS services can provide is safe, rapid transport,” underlined US Navy Special Operations Officer and Critical Care Paramedic Kenneth Byrd. “When HEMS services are requested, whether for a scene flight or an interfacility transport, it is frequently because the patient needs to get to a destination quickly. Aviation platforms offer unrivaled speed.” Technological developments have advanced pre-hospital care capabilities, refining efficacy and broadening scope. Innovations in training, progress in treatment protocols and developments in equipment continue to enhance the ability of HEMS teams to improve patient outcomes and save lives, even in the most challenging environments.
Upon arrival at the scene of an emergency, the patient is assessed so that interventions can be prioritized. “Our aim is to undertake a thorough clinical assessment (primary survey) so that we can diagnose and treat any life-threatening emergencies,” explained Prof Anil Hormis, Consultant in Anesthesia, Critical Care, Major Trauma and Pre-hospital Emergency Medicine (PHEM), and Dr Nick Tilbury, Clinical Fellow, Lincs & Notts Air Ambulance. “The team can undertake advanced patient assessment and monitoring, e.g. ultrasound assessment of the heart, lungs and abdomen and arterial blood pressure lines.” Next is the delivery of necessary interventions. “We can perform advanced interventions such as central venous access (CVC), blood transfusion, and pre-hospital emergency anesthesia (PHEA). We can also provide advanced analgesia and/or sedation for patients either with strong opioids, ketamine or by using regional anesthetic techniques,” continued Prof Hormis and Dr Tilbury. “In some situations we are also required to undertake surgical procedures that might be needed to stop bleeding or to restart a patient’s heart.”
To the heart of the issue
Indeed, the ability to evaluate, maintain and treat complex cardiovascular and circulatory issues is a critical area of expertise for HEMS providers, as Byrd highlighted: “While many field clinicians can start medications and provide fluids to begin improving cardiovascular status, HEMS clinicians must shine in the evaluation, advanced pharmacologic treatment, and management of complex technologies that support the patient’s perfusion,” he told AirMed&Rescue. “HEMS clinicians must have an in-depth understanding of cardiovascular physiology, including understanding waveforms and pressure readings from a pulmonary artery catheter. While we have seen a trend towards new technologies such as the Impella device, balloon pumps are still frequently utilized in many parts of the world, and extracorporeal membrane oxygenation (ECMO) is becoming more prevalent.”
Specifically, rapid sequence / pharmacologically assisted intubations managing difficult airways is a foundational skill for the HEMS environment
Airway skills are also crucial given the serious consequences of airway compromise and the need for emergency intubation in severe trauma cases. “Being able to secure and maintain a patent airway is a crucial and fundamental skill of a HEMS provider,” Byrd confirmed. “Specifically, rapid sequence / pharmacologically assisted intubations managing difficult airways is a foundational skill for the HEMS environment. Historically, the pre-hospital environment strayed away from sedating and paralyzing patients due to fear of inexperienced clinicians being unable to secure the airway after removing a patient’s ability to maintain his or her own airway. These days, we know that this skill offers superior intubating conditions and better patient outcomes when checklists are utilized, and pre-intubation optimization protocols are strictly adhered to. Additionally, the invention of the non-depolarizing paralytic reversal agent sugammadex has changed the risk calculus entirely. The tools available to the clinician, such as video laryngoscopes, have also made intubating much easier.”
The right support
Respiratory skills are also essential, with the need for HEMS teams to deliver effective respiratory support in many cases, as well as to ventilate and oxygenate to stabilize patients in a critical condition. “Once an airway is established, the next most important skill is ventilatory management,” stated Byrd. “Many critical care patients will require prolonged ventilatory support, and many will also suffer from complex respiratory pathophysiology such as acute respiratory distress syndrome (ARDS). A good clinician can significantly improve patient outcomes with good ventilatory support, but a bad clinician can cause significant morbidity and mortality by providing poor ventilatory support. While we have learned much from studies such as the ARDSNet ARMA study, the Covid-19 pandemic taught us that there will always be new challenges with managing complex respiratory pathophysiology. Transporting patients in the prone position was a particularly difficult concept that the HEMS providers had to adapt to and overcome during this time.”
An important technology here is the Hamilton-T1 ventilator, which is designed to manage complex respiratory conditions. “LifeFlight utilizes the Hamilton-T1 ventilator, Zoll monitor and Braun infusion devices across the rotary- and fixed-wing network,” said Dr Jeff Hooper, Medical Director, LifeFlight.
Byrd agreed: “Hamilton revolutionized critical care transport ventilation with the T1.”
Throughout assessment and delivery of care, standardization is important, with uniform protocols ensuring the delivery of consistent and reliable care
Throughout assessment and delivery of care, standardization is important, with uniform protocols ensuring the delivery of consistent and reliable care. These are built around the latest evidence-based practices and guidelines to ensure methods are as effective as possible. “LifeFlight Medical doctors, nurses and paramedics operate under a framework of standard operating procedures,” Dr Hooper highlighted. “This ensures that when critical procedures are performed in remote environments that can be resource poor, there is standardization in clinical practice. For example, having a standardized intubation checklist, emergency airway pathway and equipment means that teams have a consistent approach to rapid sequence intubation (RSI), whether that be in the field or in a rural hospital environment.”
Real-world training
The expert delivery of care is possible thanks to extensive knowledge combined with rigorous, ongoing training that ensures teams can provide the highest standards of care in even the most challenging conditions. “HEMS teams usually see the most critically ill or injured patients and so it is essential that our training is extensive and continuous,” stated Prof Hormis and Dr Tilbury. “When we are not deployed on missions, we undertake daily simulated exercises on base, to ensure that we are prepared for whatever difficult scenarios we are faced with. We will simulate procedures that we know we will have to undertake such as pre-hospital emergency anesthesia (PHEA) and setting up blood transfusions.”
Indeed, simulation plays a key role in training, enabling teams to hone their skills in a controlled environment. “We keep our skills up in HALO (high-acuity, low-occurrence) procedures by the use of simulation and case-based discussions,” said Prof Hormis and Dr Tilbury. “We undertake yearly training sessions on cadavers that cover several surgical procedures that we may have to perform in the pre-hospital environment.”
The focus of the training is on teamwork and communication under pressure
Dr Hooper said that new doctors joining the LifeFlight service must undergo orientation training. “They undertake an eight-day orientation that aims to transfer their clinical skills from emergency medicine/anesthetics or intensive care background to the retrieval environment,” he told AirMed&Rescue. “This includes simulation training with the same environmental conditions, equipment and team that they face in the real world. The focus of the training is on teamwork and communication under pressure.”
Unique techniques and novel technologies
Ultrasound is by no means a new technology, but it has rapidly become one of the newest assessment methods in the field for numerous medical ailments and traumatic injuries
Shedding light on the latest technological developments in HEMS critical care, Prof Hormis and Dr Tilbury said: “We have recently started using intra-arterial blood pressure monitoring lines (arterial lines), which allow us to continuously monitor the patient’s blood pressure. These allow a beat-to-beat recording of blood pressure and increase the accuracy compared to non-invasive blood pressure readings. This is important to monitor resuscitation and the patient’s response to treatment and is also very useful during transport to hospital.”
Another key tool is ultrasound, which enables rapid and accurate diagnosis and provides guidance for interventions. “Ultrasound is by no means a new technology, but it has rapidly become one of the newest assessment methods in the field for numerous medical ailments and traumatic injuries,” stated Byrd. “It is relatively easy to learn with a relatively low cost compared to many other imaging modalities. It can be employed rapidly and provides a significant amount of additional assessment data.
“The main drawback to ultrasound is that it takes many years for the average clinician to begin mastering many of the techniques and interpretation of the data. While extended focused assessment using sonography in trauma (eFAST) and many of the frequently taught trauma exams are relatively quick to learn, a difficult patient may be extremely difficult to interpret (much like a difficult intubation).
“The good news is that there are relatively few contraindications to utilizing this technology, outside of focusing on more important patient care first. For example, obtaining a cardiac ultrasound during cardiopulmonary resuscitation (CPR) must be done with judicious attention to maintaining chest compressions. One of the more ‘fun’ studies I have been involved in required performing ultrasound on neonates through the fontanelle to assess for intracranial hemorrhage. New and unique techniques like this are being utilized every day in the transport environment.”
Prof Hormis and Dr Tilbury said that portable ultrasound machines are also used in their service: “We can assess the heart, lungs and abdomen in critically ill patients to identify serious pathology and help guide treatment decisions. We can also use the ultrasound machine to locate nerves so we can undertake regional nerve blocks for pain control.”
Dr Hooper highlighted digital innovations that are enhancing care: “LifeFlight utilizes a medical app for offline access to medical standard operating procedures (SOPs), drug library and pediatric calculations, which allows doctors to access critical information in remote areas. Future developments will be improvements in remote patient monitoring, and the incorporation of the Powered Aero Loader (PAL) patient loading system into the new aircraft. Teaching and training of the medical team using virtual reality (VR) is an emerging technique.”
Prof Hormis and Dr Tilbury have been trialing a machine that can expedite blood results and therefore appropriate care delivery: “It analyzes the patient’s blood and gives us a reading of the acid-base status of the patient as well as other chemical markers such as potassium and calcium. Knowing these results in the pre-hospital setting can identify certain conditions that require immediate action.”
The lighter, the better
Among the key challenges faced by HEMS teams in the provision of pre-hospital care is the need for lightweight devices that take up minimal space. “To be fast and safe, things must be light and small,” said Byrd. “Everything onboard the aircraft must be as light as possible and as small as possible to safely transport patients of all sizes. While it is currently difficult to fit an ECMO circuit, balloon pump device and numerous pumps and ventilatory support equipment aboard an aircraft, it will become easier and easier in the future as these devices become lighter and smaller.”
Another challenge that Byrd underlined is the high cost of helicopters and the advanced equipment required to provide advanced care. “Hopefully this is one of the ways that I see the industry evolving, with costs lowered as technology and manufacturing processes improve. We have already seen the costs of some previously novel technologies, such as point-of-care ultrasound, dramatically decrease thanks to advances in technology,” he said.
We have already seen the costs of some previously novel technologies, such as point-of-care ultrasound, dramatically decrease thanks to advances in technology
HEMS teams also face the perpetual difficulty of operating in challenging environments, requiring expert coordination and communication. “Pre-hospital care provides unique challenges to the HEMS team – it requires a flexible, adaptable approach to working in environments that can be unpredictable and fluid,” said Dr Hooper. “Accurate patient information prior to landing can sometimes be difficult to achieve. Given the long-distance nature of our taskings in Queensland, there can often be deterioration in the patient’s condition prior to arrival of the HEMS team. LifeFlight teams are trained to work in these conditions, to rapidly stabilize the patient, [and] provide critical interventions in the field such as intubation, blood and chest procedures.”
Future evolution of critical care
Advancements in technology, protocol and training are set to continue shaping critical care delivery onboard HEMS. Prof Hormis and Dr Tilbury provided an insight into particular interventions that hold future promise: “There are plans to look at providing highly advanced endovascular resuscitation techniques for our patients such as retrograde balloon occlusion of the aorta (REBOA) and ECMO for a small subset of critically ill patients. These will take several years to become embedded but are being trialed in pre-hospital services in the UK and abroad currently. The evidence suggests these may be beneficial interventions for our patients at the point of injury and within a defined timeline.”
Byrd also highlighted the potential of REBOA: “It has been utilized for several years now to delay death in patients suffering massive trauma until they can successfully undergo trauma surgery. This technology has been saving lives and it’s only a matter of time before HEMS crews are being trained to utilize it more frequently,” he said.
“In addition, extracorporeal cardiopulmonary resuscitation (E-CPR) or placing cardiac arrest patients on ECMO has really been accelerating in recent years. The neurologically intact survival rates for the patients far exceed that of traditional CPR. While there is currently a very large barrier in the way of cost and training, I foresee that gap closing in the future and this technique becoming more and more frequent.”
From VR simulation training and cutting-edge medical advancements to technological developments such as the Hamilton-T1 ventilator, continued progress will keep advancing HEMS critical care. “The future of HEMS is poised for significant advancements with the integration of cutting-edge technology and innovative care protocols,” concluded Prof Hormis and Dr Tilbury. “Artificial intelligence (AI) will become more prominent in the near future, be that in tasking and allocation, or pre-hospital diagnostics. There are also likely to be significant advances in portable imaging equipment available to HEMS teams that can allow images to be remotely delivered to hospitals in preparation for the patient. Continuous training and the development of new equipment will ensure that HEMS teams are always prepared to provide the highest level of care, ultimately improving patient outcomes and saving more lives.”