Treatment of gunshot wounds

Traumatic Times

For flight medics, sadly, treating gunshot and stabbing victims is becoming ever more common. James Paul Wallis spoke to experts about the trends they are seeing and care they have to render

According to London’s Air Ambulance (LAA) statistics for the last year, stabbing and shooting were the most common causes of injury amongst its patients, ahead of road traffic collisions. The charity’s helicopters and rapid response ground vehicles delivered advanced trauma teams to treat 560 victims of stabbings and shootings in 2017, a 12-per-cent rise compared to the previous year.

It’s not just crews in capital cities that deal with gunshot wounds (GSWs). Also in the UK but covering less densely populated urban and rural areas is East Anglian Air Ambulance (EAAA), which hit the headlines a couple of years ago when it dispatched a helicopter (piloted by Prince William, as it happens) after a man was shot in an attempted murder in the quiet market town of Bury St Edmunds. And it’s not always due to criminal activity. This June, for example, US service Vanderbilt LifeFlight transported a nine-year-old boy who’d been accidentally wounded while shooting targets with his father.

Given the prevalence of gun crime globally, it makes sense for air ambulance crews to prepare themselves to deal with the after-effects of such incidents.

Penetrating trauma

In many ways, GSWs are just a type of penetrating trauma. Dr Mark Nash of Midlands Air Ambulance commented: “Both shootings and stabbings come under our chest injury clinical guidelines and trauma management guidelines.” What’s unusual about GSWs, though, is the speed with which the bullet enters the body, which can lead to the creation of a cavity that’s initially filled with hot gasses. The nature of the damage caused depends on the energy carried by the projectile at the point of impact, the path it takes through the body, and whether it deforms on entry, for example by fragmentation. There is a high risk of significant injury including organ damage, bone fractures, blood loss and disruption to the central nervous system. The internal damage may be more severe than the external wound might suggest.

Presence / absence of an exit wound is important to know, especially in cavity wounds such as chest/abdominal
Dr Ami Jones

Particular considerations for initial assessment of GSWs is that it can be helpful to establish what type of weapon was used (the victim or any witnesses may be able to advise), and to remember to check and treat not only the entry wound, but also any exit wound. Dr Ami Jones, Dafen Base Lead and former National Director of EMRTS Cymru, noted: “Presence / absence of an exit wound is important to know, especially in cavity wounds such as chest/abdominal." 

Injury patterns are likely to be more severe if the bullet hasn’t exited, she said.

The emphasis for the emergency responder is to transport the victim to a care facility as quickly as possible, only delaying transport to provide care if it’s needed to help the patient survive the trip. There have even been retrospective studies seeking to identify whether shooting victims have better outcomes if taken to hospital via a nearby private vehicle rather than waiting for a ground ambulance to arrive. Having said that, in many cases patients wouldn’t make it to hospital without lifesaving pre-hospital treatment. Let’s look at some of the options.

londons air ambulance gunshot treatment

Bleeding control

Tourniquets have been used for thousands of years to control bleeding in the extremities, particularly in the military, and they continue to be carried by soldiers on the battlefield today. There has been controversy over the use of tourniquets in the civilian setting, however, due to the risk of complications such as ischaemia – tissue damage due to loss of circulation. The Royal College of Surgeons of Edinburgh issued a position statement in 2017, noting that recent military practice had influenced a reintroduction of tourniquets into civilian practice. The College warned: “Tourniquets should only be used as a last resort after other stepped measures have failed except in complete traumatic amputation where a tourniquet should always be applied.” The College added that tourniquets must be used correctly or not at all, saying: “An inappropriately used tourniquet can be harmful and an incorrectly applied tourniquet will cause increased bleeding from distal soft tissue injuries and damaged arteries if there is occlusion of the lower pressure venous outflow, but inadequate occlusion of arterial blood flow i.e. the tourniquet is not tight enough.” The advice provided was to apply the tourniquet as rapidly and as close to the wound as possible, directly to the skin to prevent slippage, and tightly enough to arrest haemorrhage. If required, the tourniquet should be tightened or a second tourniquet applied above the first, said the College.

inflatable tourniquets have been introduced for controlling abdominal bleeding

Dr Ami Jones noted that most bleeding will be controlled with simple pressure dressings and advised caution when using tourniquets: “Clearly, tourniquets have a good pedigree for limb injuries where bleeding can’t be controlled with direct pressure/indirect pressure or haemostatics, but be sure that this is the only way to control the haemorrhage, especially if evacuation timelines might be prolonged … applying a tourniquet means that patient now needs immediate evacuation so as not to render their limb ischaemic, which may not be possible.”

Looking at recent innovations, inflatable tourniquets have been introduced for controlling abdominal bleeding. SAM Medical of the US produces the SAM Junctional Tourniquet (SJT), which is designed to control bleeding in the inguinal and axilla areas. The SJT can also help to stabilise pelvic fractures, says the company.

Another traditional approach is to stuff a wound with gauze and apply pressure. These days, special gauze is available with compounds that promote clotting. UK-based Celox Medical produces gauze impregnated with chitosan, a biodegradable substance derived from the shells of shrimp and other crustaceans that promotes clotting. In January 2018, the firm announced that the UK Ministry of Defence had placed an order for its Rapid haemostatic gauze for use in all branches of the military. According to the company, the gauze ‘can stop life threatening arterial bleeding in under 60 seconds’. The firm also sells granules, which can optionally be delivered using an applicator designed to treat narrow penetrating injuries.

New treatment methods continue to come onto the market. This April, RevMedx gained CE Mark Certification for its XSTAT 30 and smaller XSTAT 12 haemostatic devices, which feature a syringe-like applicator used to introduce sponges into a wound, where they rapidly expand to exert pressure to reduce bleeding. The US-based company said that unlike traditional wound treatments that may take several minutes to be effective, XSTAT can stop bleeding in seconds to stabilise injuries until patients reach an emergency facility. The devices have already been cleared by US authorities and have seen use with the US military. They are promoted for treating narrow-entrance penetrating wounds in parts of the body that aren’t suitable for tourniquet application. A large model is suitable for exit wounds from high-powered weapons, while a smaller version is sized for entry wounds and for lower-powered rounds.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an entirely different technique to reduce bleeding in patients with pelvic haemorrhage. It involves feeding a balloon into the lower end of the aorta, the largest blood vessel in the body, and inflating it to temporarily prevent further blood flow to damaged vessels. LAA claimed a world first when it announced in 2014 that it had performed pre-hospital REBOA. Speaking at the time, Professor Karim Brohi, Consultant Vascular and Trauma Surgeon at Barts Health NHS Trust, which worked with LAA, reflected: “While it sounds relatively simple, it is an extremely difficult technology to deliver in the emergency department in hospital, never mind at the roadside. This successful deployment of REBOA represents nearly two years of development work by our staff.”

Don’t rush to RSI patients who haven’t been haemodynamically resuscitated unless they are in airway extremis
Dr Ami Jones

Along with the above methods to reduce bleeding, it helps to have access to blood to give the patient. Dr Ami Jones commented: “Blood / blood products and a way to warm them are critical.” Underlining the importance of getting blood into the patient, she said: “Don’t rush to RSI [rapid sequence intubation] patients who haven’t been haemodynamically resuscitated unless they are in airway extremis." In January 2018, US-based air medical provider Air Methods shared the story of Trip Collins, who accidentally shot himself when he was just three years old. According to the service, the ability of the LifeNet 3 helicopter crew from Orangeburg, South Carolina, to administer blood was a key part of his survival.

IV fluid gunshot wound

Chest wounds

A GSW can create a sucking chest wound, as the hole created by a bullet creates a new pathway for air to enter the chest cavity (pneumothorax), which can lead to a collapsed lung. It can be prudent to treat any penetrating wound to the chest as a sucking chest wound, as it isn’t always easy to determine whether air is entering. To prevent air ingress, a chest seal can be placed over the wound. The simplest devices are little more than sterile plastic with an adhesive backing, while more advanced examples feature a vent to allow any excess air inside the chest to escape. In an emergency, the plastic packaging from any sterile dressing can be opened out and placed against the chest (clean inside surface down) and taped to seal.

Dr Ami Jones advised: “In a spontaneously breathing patient, chest seals are important, but you only really need one on each side of the chest; the other wounds can just be covered with a dressing but the dressing should properly seal the wound.” She cautioned to watch out for chest seals occluding with blood and to replace them if they become blocked.

Dr Jones also noted that a patient whose breathing is compromised will need an RSI and one or more thoracostomy (where a small incision is made through the chest wall using a needle or chest tube to drain air or fluid from the lungs and reduce pressure on the heart and lungs). The similarly-named thoracotomy is a more drastic procedure – essentially open-chest surgery – used in more serious cases.

LAA was the first in the UK to offer on-scene thoracotomy for patients suffering traumatic cardiac arrest and boasts a success rate for the procedure of 18 per cent, which it says is the highest in the world.

For fixed-wing air ambulance providers, key considerations for GSW patients include the effects of reduced air pressure and the length of transport. US-based Trinity Air Ambulance is one provider that has experience of treating such patients. Medical director Jeff Levy suggested carefully checking for undiagnosed pneumothorax, which could prove fatal at altitude, and also carefully checking the patient’s oxygen needs.

celox gauze

Mass shootings

In July 2011, Norsk Luftambulanse was among the agencies that responded to a mass shooting by a lone extremist at a summer camp on Utøya island. He killed 68 people and injured 110 more. Asked whether the incident had led to an increase in the level of preparedness in the country for dealing with GSWs, Stephen Sollid, Head of the Prehospital Division at the Stavanger University Hospital and former Chief of Medicine at Norsk Luftambulanse, responded: “The general awareness on GSW and massive external bleeding is higher than before 22 July 2011 and most HEMS bases have improved both training and equipment setup for this. Mostly however, the changes that have been implemented are in regard to the general preparedness and how situations with ongoing violence are handled.”

The incident also served to demonstrate the effectiveness of ‘load and go’ as ‘the most important strategy in mass shootings with multiple victims’. It also showed that triage can be a challenge with many ‘red/critical’ patients. Sollid commented: “We believe that this justifies the use of doctors in HEMS, since doctors with pre-hospital training are better suited to do the ‘fine triage’ of critical patients, at least in our setting where distances to the nearest trauma centre is a major factor and transports are long. So, in principle ‘bringing the hospital out to the patient’ is in our opinion critically important here.”

For dealing with mass shootings, Sollid advised: “Be prepared to do difficult triage of multiple seriously and critically injured people, and be prepared for having to triage people as dying (aka alive, but untreatable or not a priority with multiple serious casualties when EMS capacity is maxed out).”

The injuries seen in 2011 were greatly affected by the type of ammunition used, Sollid said: “All victims from the Utøya shooting were injured by hollow point ammunition. This causes injuries with little external damage, but often major internal damage. These victims either die within few minutes due to massive internal bleeding and organ damage, or survive up to several hours even with torso and extremity injuries.”

Other than the medical aspect, one outcome from Utøya, Sollid noted, was that a new national procedure was put in place under which EMS and fire/rescue personnel can intervene and take out the perpetrator if police are not available (a common problem in Norway, he said, where police presence is low because of a low threat situation in general).

Safety first

Perhaps the key factor that differentiates GSWs from other trauma calls is the importance of ensuring the scene is safe to enter. Dr Mark Nash, Clinical Lead at UK charity Midlands Air Ambulance, said: “The police are usually involved and will have entered the scene first to ensure the safety of the aircrew and other parties. The aircrew would need to wait for the OK from police before entering an incident scene where gun crime has been confirmed. As with all emergency services, staff safety has to come first.”

The Emergency Medical Retrieval Transfer Service in Wales (EMRTS Cymru) works in partnership with Wales Air Ambulance Charity to fly consultants and critical care practitioners to deliver pre-hospital care across Wales. Dr Ami Jones said that the medic’s own safety should be considered at all times. “This may be tricky,” she warned, “in an MTFA (marauding terrorist firearms attack) incident when the hot and warm zones are interchangeable, so just consider whether where you’re giving your care is the safest place for you and your patient.”