Old habits are hard to break, though not a good idea and highly discouraged, traditionally EMS personnel will run to the patient before rescuers have time to stabilize the vehicle and shut down the electrical system. With the new systems of today’s vehicles EMS personnel must keep a few rules in mind when doing this.

Rule #1. When approaching the patient, never lean through the window of the vehicle. Most of today’s vehicles are equipped with curtain airbags, these airbags deploy straight down approximately 18 inches, or from the roof to the bottom of the window and are capable of snapping a persons neck.

Rule #2. If the door is able to be opened, rescuers must be aware that a live door mounted airbag may be behind them while working on the patient. It is a good idea to secure the door open with a rope or strap so it can not close against them. Never use a prop, as it is easily kicked loose or becomes a tripping hazard.

The inflation zone for these airbags is 5 inches from the door panel.

Today, not only the later but, all frontal airbags must be considered dual stage, because as can be seen here; when installed in the vehicle it is impossible to tell which one is an earlier single stage and which one is a later dual stage.

Rule #5. Always cut the seat belt, there are many reasons for this.

One being today’s vehicles are equipped with pyrotechnic seat belt tensioners, if the tensioner is accidentally ignited, the belt will suddenly snap the patient back against the seat, possibly furthering a spinal or chest injury.

Another reason is that to unbuckle the seat belt the rescuer must lean over the patient putting him or her self within the inflation zone of the frontal airbags.

A third reason is: By unlatching the belt we leave the metal buckle hanging loose. If the tensioner is ignited, the swinging metal buckle could cause injury to you or the patient but, if the belt were cut, the loose strap would simply spin around the spool.

Also if a crash is sever enough to deploy an airbag, always check the patient for seat belt injuries. These belts are pyrotechnic and deploy the same as the airbags, the force of the belt retracting combined with the momentum of the patient being thrown forward can cause injury to the chest and abdomen. 

Rule #6. Never enter, lean on, or lay any type of equipment on an empty passenger’s seat until the electrical system is shut down and the capacitor drain time has expired.

These seats are equipped with hidden weight sensors that control the deployment of the passenger’s frontal airbag. If the seat was empty at the time of the crash, the airbag would not have deployed.

Warning! With the electrical system still intact any weight placed on the passenger's seat would alert the control module to open the path for a deployment. (See details in the passenger's airbag section, under weight sensors)

Instructors do not always agree on some techniques. One of these is the moving of the seat. Most of the seats today are electrically operated and many instructors teach that the seat needs to be moved back before the battery cables are disconnected. Others teach that because the airbag deployment has already happened, the system is stable and by moving the seat, the seat position sensor would cause the system to open the path for a second deployment. (See seat position sensors for details)

A good rule of thumb in this situation is: If the back rest is adjustable, tilt it back rather than move the seat. If it is not adjustable and the patient is within the inflation zone, such as a single cab pick-up, be sure the seat is moved to it farthest point, incase of an accidental deployment.

Another tip is that the back rest of a seat can be removed with a reciprocating saw within seconds, giving the rescuer much more room to operate.

As rescuers and EMS; we are going to see some airbag deployment injuries. Most of these injuries are going to be minor chest and facial wounds, much like a carpet burn. Though they are minor wounds, EMS personnel, with out fail should document and report these wounds.

Warning! Any direct contact with a deploying airbag can produce hidden brain, chest and spinal damage, which the patient may not realize at the time.

This report should include the severity of the crash, whither minor or major, the angle of impact, whither the victim was wearing a seat belt or not, the airbag that was contacted and the number and location of any other airbags that were deployed.

At this point even though the vitim looks and acts alright, in twenty minutes when the brain begins to swell, we could have a life threatening situation on our hands.    

Terminology

With the development of side impact airbags, EMS personnel must remember the proper terminology for these airbags.

For many years we reported the steering wheel airbag as being the driver’s side airbag. Today this would lead doctors to look at a totally different mechanism of injury. The steering wheel airbag should be recorded as the driver’s frontal airbag and the same with the passenger’s 

Upon arrival, many times the vehicle will be filled with what looks to be a cloud of smoke, causing many people to believe the vehicle is on fire. This cloud is mainly made up of cornstarch or talcum powder used to keep the airbag from sticking together while folded in the module. It is estimated that only about 2% of this cloud is actually smoke, which has escaped through the filters of the inflator.

Rescuers should immediately ventilate the vehicle by opening the doors or windows. This powder is not harmful, but it can cause minor irritation to the eyes and lungs, along with the fear of the vehicle being on fire, this could cause the patient to panic increasing the risk of shock.

Also in a major crash, the patient could have chest damage, and with the irritation of the powder causing coughing, it could produce future damage.

Warning! Though it is normal procedure, it is especially important that any patient experiencing an airbag deployment, whether properly or hit by the bag, be fitted with a C collar and total spinal alignment maintained.

Rarely found but very possible

This smoke is made-up of the chemical byproducts of the burning Sodium Azide, one being hydrozoic acid, a highly toxic gas. Another is sodium hydroxide, better known as lye or caustic soda. Both of these are very corrosive and can cause severe burns to all tissues that it comes in contact with, if exposed to too large of amounts. Inhalation of low levels of these as dusts, mists, aerosols or gases (Smoke) may cause irritation of the nose, throat, and respiratory airways. Inhalation of higher levels can produce swelling or spasms of the upper airway leading to obstruction and loss of measurable pulse; inflammation of the lungs and accumulation of fluid in the lungs may also occur. Another is potassium chloride or potash; this chemical when exposed to oxygen actually becomes what we know as baking soda. It very quickly absorbs moisture, drying and irritating the eyes and the membranes of the nose and throat.

Though rare, these chemical can cause some physical problems and with the driver’s and passenger’s airbags deploying at the same time, the amount of these chemical is greatly increased. Because manufacturers have started using more compress gas inflators much of this problem is slowly being eliminated. 

Thermal Burns

One of the big debates about airbag injuries is airbag burns. Many say that they are not actually thermal burns, but rather abrasions from the contact with the nylon bag. This is normally the case, although some are actually thermal type burns. It seems that medical reports, world wide, pretty much agree on the numbers, it is reported that approximately 1.53% of these injuries are actually thermal burns.

The most common being burns to the driver’s arms and hands. This is caused from the hands being placed on the steering wheel in close proximity to the exhaust or deflation holes in the rear of the airbag when it deploys. Notice the smoke exiting the two holes in the picture. The airbag deployment happens so fast that the victim can not move their arms and the hot gases escaping the bag is in direct contact with the skin.

EMS should be very suspicious of sever under lying injuries if these thermal burns are found on the chest or face. These gases are extremely hot when they enter the airbag, but cool within milliseconds. If a thermal burn is found on the victim’s chest, it would have had to happen when the gases were entering the bag, (or at their hottest point). The reason being; they would have cooled in about 25 milliseconds and been exhausted from the bag within about 40 milliseconds. This means the victim probably sustained a direct hit in the chest with the force of the deploying airbag.

Airbag-related chest wall burn as a marker of underlying injury: a case report:

by Simon J Monkhouse and Michael D Kelly

Department of Surgery, Frenchay Hospital, Bristol, UK

A 65-year-old man was involved in a moderate speed, frontal impact road traffic accident. He was restrained by a three-point fixation seat belt and his frontal airbag deployed appropriately in the collision. He was assessed by paramedics at the scene and was brought to the emergency department for assessment; although it was felt he had no serious injuries apart from a forehead laceration. His head was sutured and he was assessed as fit for discharge.

However, he reported increasing chest pain, which was unresponsive to simple analgesia. A routine chest x-ray was performed and reported as showing no evidence of pneumothorax or rib injury.

He was admitted to hospital overnight. The following morning, he was reporting chest pain and was short of breath.

 Examination revealed a small, distinct chest wall burn and a CT scan of the thorax demonstrated comminuted sternal and manubrium fractures. There was also a significant retrosternal haematoma. Electrocardiogram and echocardiography were unremarkable. He was admitted for conservative management which included serial observation, chest physiotherapy and opiate analgesia. He made a steady recovery and was discharged from hospital four days later.

Conclusion

 This case is of enormous importance to emergency staff. The burn was exactly over the point of sternal fracture and served as a marker of serious underlying injury. The highly localized nature of the burn indicates that the forces involved in the airbag deployment were focused on this point. The educational point here is that in a patient with a chest wall burn sustained during airbag deployment, treating clinicians should be suspicious of an underlying thoracic injury. Appropriate imaging is necessary to rule out a serious chest wall injury as plain films and clinical examination can be misleading. In addition, all drivers should be encouraged to sit back from the steering wheel at a distance of at least 25 cm to minimize the risk of injury due to adverse explosive forces.

 The same is true for facial burns, the victim may have been hit by the deploying airbag when it was at its hottest point or the victim may have been unconscious for a period of time and slumped over the hot airbag for a prolonged period. Either way there would be a danger of hidden head or spinal damage.  

Cabin Pressure

Another EMS concern brought on by the addition of the passenger’s airbag is sudden cabin pressure change.

Many times a victim will experience a temporary lose of hearing after an airbag deployment.

Most people believe that the tremendous noise of the airbags deploying is what causes this.

Though this may be partially true, the main source of this is the sudden change of atmospheric pressure within the vehicle. If the windows are rolled up, when the deployment takes place, the sudden blast of gases entering the cabin will drastically increase the atmospheric pressure. The tighter the cabin and the more airbags deployed at the same time, the greater that increase becomes. In a frontal crash, today’s vehicles could very easily deploy two frontal airbags and two knee airbags at the same time. This sudden change puts pressure on the ear drums, causing the temporary lose of hearing and usually a ringing in the ears.

 This same pressure can also affect the eyes. Airbag deployment happens much faster than the eye blinks, this means the victims eyes were probably open at the time of the deployment and this pressure along with the talc, sodium hydroxide and potassium chloride, from the deployment, was applied to the eye ball itself, temporarily impairing their vision.

In this case it may be a good idea to flush the eyes to stop the sodium hydroxide and potassium chloride from further irritating them.