What happens in Pre-hospital Care
Trauma is the commonest cause of death in the 0 – 39 year old age group in Western society. Road traffic crashes cause 320 000 injuries, 40 000 serious injuries and 3 400 deaths in the United Kingdom each year. Approximately 13% of all road traffic accident deaths result purely from an obstructed airway, such as occurs when an unconscious patient’s tongue falls to the back of their throat.
Sudden death from a cardiac event is also a major killer in the under 65 age group. Often the disturbance of heart rhythm that causes death has not been caused by the death of heart muscle to a degree that would make life impossible. With modern thrombolytic (clot-buster) drugs and defibrillators the outcome of a person who has a cardiac arrest is much better than ten years ago.
When dealing with casualties from either trauma or medical causes we must follow a well practised routine to ensure that we can give the casualties the best possible care in situations which are often far from ideal.
The Trimodal Distribution of Death from trauma was first described in 1983 by an American Traumatologist, Donald Trunkey. In the the first phase death occurs within seconds or minutes of the accident and is due to major severe injuries of:
The brain – producing injury not suitable for surgery.
The heart and great vessels.
The cervical spinal cord.
The injuries sustained in this phase are rarely treatable. Only accident prevention will reduce the mortality in this group. In the second phase death occurs in minutes or hours and the focus of pre-hospital care has traditionally been on this group. There may be treatable but life threatening injuries of :
The skull – blood clot formation which must be surgically treated.
The chest – bleeding into the chest (haemothorax), bruising (pulmonary and cardiac contusion) or collapsed lungs (pneumothorax)
The abdomen – injury producing haemorrhage which requires surgical treatment.
The skeleton causing fractures with large blood loss especially from the pelvis and long bones (e.g. the femur).
In the third phase death occurs days or weeks after the accident and may account for 30% of accident deaths. Deaths may be due to :
Multiple organ failure
Deaths in this group may be thought to be an “in-hospital” problem but when the cause of death was analysed it is often found that deficiencies in the primary resuscitation may have played a significant role in the pathological process leading to the subsequent death.
The late Dr R Adams Cowley is credited with coining the term “Golden Hour” to represent the period of time a healthy person with life threatening haemorrhage could survive. External haemorrhage can be controlled at scene but bleeding into the chest, abdomen or skull requires a surgeon’s intervention. Within the Golden Hour the Emergency Services need to arrive at scene, rescue the casualty, transport them to hospital, where they have to be processed through the system to arrive at the operating table. This means that the pre-hospital worker has relatively little time known as the platinum ten minutes. Whilst the Golden Hour remains a useful concept as a teaching tool recent studies have thrown the concept into question. The time was never based on evidence but was an arbitrary time based on the experience of a single surgeon. Whilst evidence shows that indeed there is a weak correlation between time to surgery and survival there is no clear time period. If trauma death is to be reduced the concept of early treatment must be followed using established guidelines. Rather than the therapeutic vacuum where little treatment was offered to patients following accidents before they arrived at hospital we must create a therapeutic response.
With life threatening illness, and in particular with heart attacks, the key to success is the so-called Chain of Survival. This relies on the casualty or those around them identifying the serious nature of the illness before cardiac arrest occurs. If it does, then bystander cardiopulmonary resuscitation is life-saving, in that it sustains the circulation to the brain for the vital minutes it takes an ambulance to respond. Early defibrillation is the best method to restore the cardiac action, and defibrillators are now so sophisticated that anyone can be trained in their use. Following successful defibrillation good advanced cardiac life support during and after transfer to hospital gives the greatest chance of the individual leaving hospital.
Managing Treatment In Pre-Hospital Care
There are two fundamental rules which should never be broken. If they are you are putting your life and that of the casualty at risk.
Scene safety is an extensive topic. It is all to easy to tell a rescuer to look for danger, but not to identify what constitutes a hazard or to describe a safe working practice for that situation.
Calling for Help
The emergency services in the United Kingdom are generally mobilised by the use of the 999 telephone system. A less widely publicised number is the Europe wide emergency number, 112.
Mobile phones create a particular problem for the Emergency Services, that of location. Whilst a land line is registered to a location a mobile phone call to say that there has been an accident on the A6 is of little value. The following information is therefore required:
E Exact location
T Type of Incident ( Road, rail, factory accident, fire etc)
H Hazards if any ( Power lines down, fuel spilt, chemicals etc)
A Access (Best way in)
N Numbers of Casualties
E Emergency services required
The basic principles revolve around a systematic approach. This is based on:
Resuscitation and stabilisation
Packaging and transfer
This allows the systematic identification of life threatening problems. Once a life threat is recognised it must be treated before the next stage is started. The Primary Survey utilises the A,B,C concept. This concept can be extended to become A,B,C,D,E.
Airway With Cervical Spine Control
As well as assessing the airway, the neck in the injured patient is controlled by gentle in-line stabilisation. If the airway is compromised it must be treated during this phase.
Breathing with oxygen administration
Any problem with the breathing including inadequate ventilation must be treated next. Oxygen should be used whenever available.
The aim is to stop external bleeding and control shock by replacing fluids. After this the primary survey must be repeated.
The aim of the A,B,C is to diagnose or recognise a life threat. Once resuscitation is started the aim is to stabilise the patient. It must be accepted that in some instances and with certain injuries the patient cannot be stabilised. This is the situation where the "load and go" approach has to be applied. Only the surgical team will be able to stabilise the patient in theatre in hospital.
This is a quick assessment of the conscious level. The AVPU system is used in the primary survey.
Is the patient Alert ?
Do they respond to your Voice ?
Do they only respond to Pain ?
Are they completely Unresponsive ?
Also note the state of the pupils, as equal or unequal and reacting or not.
This is the detailed head to toe survey of the casualty where injuries, lacerations, bumps, bruises and fractures will be recognised. If a critical emergency has been identified during the primary survey there may not be time to move on to the secondary survey. Most Immediate Care practitioners will tend to teach the E as representing “How do I extricate this casualty from this situation?” and “By what means should I evacuate my casualty to definitive care?” These questions may in fact need some considerable work to resolve, such as the use of specialist Fire Service equipment or Search & Rescue helicopters so actually need to be considered at an early stage.
At each stage the vital signs and observations should if possible be recorded to assist handover at the hospital. At all stages there must be re-evaluation. If the patient develops a problem, the PRIMARY SURVEY must be repeated. This means going back to the A,B,C again and again. The neurological status must also be reassessed using the AVPU system. Once the patient is stable and ready for transport the aim is to transfer the patient safely to hospital. If there are multiple casualties then the aim is still the same. This is to send:
The RIGHT patient to the RIGHT hospital in the RIGHT time.
Recently the spate of military casualties and civilian casualties from terrorism have forced a re-evaluation of ABC in some circumstances, and if life threatening haemorrhage is present then CABC is now advised, where control of the haemorrhage actually comes before airway management.
It is essential that a good patient report is given to either the ambulance or medical services at hospital. A correct patient handover avoids unnecessary patient disturbance and provides the hospital with a complete picture when the casualty finally reaches the Accident and Emergency department. The report needs to be clear and concise, yet transfer all relevant information. The recommended format for give a casualty report can be remembered by the use of the mnemonic ASHICE.
I Illness or injury
C Cause for concern
E E.T.A. (Estimated time of arrival)
Alternatively the military mnemonic of MIST may be used.
M Mechanism of injury
S Vital signs
T Treatment given
Whatever system is used the end result needs to convey the required information succinctly. For example:
“48 year old male in high speed roll-over RTA. Trapped 45 minutes. Head, facial and chest injuries, bilateral femoral fractures. Pulse 130, absent radial, tubed, ventilated & right sided chest drain. sats of 94%, 2 litres Hartmans given, ETA 12 minutes”
In every situation, the aim should be to correctly assess the casualty, institute appropriate treatment and then to correctly hand over the patient and problem using a logical report format. Although we have set down an ideal approach to casualty care we must recognise that the way any particular rescue is managed may be significantly influenced by other external factors. Of these, the environment is important, as is the safety of both the rescuers and the casualty. This will influence the approach taken. The question which needs to be answered at every stage of the rescue is:
“Has this casualty received the best possible care from me, taking into account the casualty’s injuries, the environment and my knowledge and skills” ?