Offering structure to assess and treat the most life-threatening conditions first is the ‘Primary survey’ assessment. The Primary survey is a rapid and structured approach to assessing a patient for any immediate life-threatening deficit and should take no longer than 90 seconds to complete. The flow of the assessment and reasons are as follows:

• Catastrophic Haemorrhage (C) – If the patient is rapidly losing a large volume of blood their condition will quickly deteriorate through a cascade of negative pathophysiological events: lack of oxygen and nutrient carrying/perfusion capability, increase in cell anaerobic activity causing acidosis, lack of ability to maintain organ perfusion and blood pressure, and overall negative/catastrophic impact to the body’s homeostatic balance. Blood loss can be difficult to replace within the pre-hospital setting.
• Airway with considerations for C-spine (A) – If the patient has lost their airway, Oxygen is unable to enter the lungs to help metabolise cellular activity and Carbon Dioxide cannot leave. This hypoxic and hypercapnia state quickly starts causing cellular disruption and death, affecting organ function and pH levels, and overall negative pathophysiology.
• Breathing (B) – Similar to Airway, with reduced or no respiratory effort from the patient, gaseous exchange is severely affected or unable to happen in the lungs, causing cellular disruption and death, affecting organ function and pH levels, and overall negative pathophysiology.
• Circulation (C) – If circulation is affected to a certain part or all the body either through medical and/or traumatic means, then perfusion of the cells/tissues/organs can be affected. Depending on the severity of the circulatory problem will affect the negative outcome on the normal state of the body.
• Disability (D) – Looking at the effects of a reduced level of consciousness and its’ cause, this may have increased detriment to the patient. For example, a gradual hypoglycemic event will affect the patients’ level of consciousness and homeostatic level. As this worsens further issues may develop, such as the patient becoming unconscious and putting their Airway at risk.
• Expose/Environment/Evaluate/Evacuate (E) – The last assessment of the primary survey encompasses different elements of surrounding and situational circumstances. The clinician will need to consider and question a number of factors surrounding ‘E’ such as: Will exposing the patient through clothing removal reveal further injury, is the environment a factor to their ill health (such as Carbon Monoxide poisoning) or will it further adversely affect the patient (such as hypothermia), is there a need for further evaluation, and is it time to evacuate the patient to hospital.

The structure of the survey is designed so that the most serious/life threatening complaint is identified and dealt with first i.e., what is going to cause the most irreversible damage and threat to life. This stepwise and systematic approach allows a chance for the complaint(s) to be managed, potentially allowing the patient to recover from the event and return to a normal homeostatic state, or provide them time to receive further advance care or hospital treatment.

Special considerations when looking at the primary survey;

• Always be aware of the safety aspect throughout. Be aware that there may be dangers present to you, your colleagues, or the patient, which will require you to don PPE, request Police or Specialised back up, or may just mean that you cannot approach the scene because it is too unsafe.
• An initial review of mechanism of injury (MOI) or the ‘gut’ feeling that a patient looks unwell may give you an indication of how severe their injuries may be or how unwell they are.
• If you cannot rectify a life-threatening deficit on the Primary survey then you will need to consider early advanced back up and/or early rapid transport to hospital for specialised care.