The primary survey is a rapid, systematic assessment performed on an injured or critically ill person to quickly identify and manage conditions that cause immediate death. This process prioritizes intervention over detailed diagnosis, following the principle that a patient must be stabilized before a full investigation can occur. The goal is to address the most time-sensitive threats, specifically those affecting the ability to breathe, circulate blood, and maintain brain function.
Immediate Airway and Breathing Threats
The most immediate threats involve the airway and breathing, which are assessed and managed simultaneously. An obstructed airway, caused by a foreign body, the tongue falling back due to unconsciousness, or trauma, prevents oxygen from reaching the lungs and is an immediate emergency. Asking the patient a question is the quickest way to assess patency; if they can speak clearly, the airway is likely open and functional.
Once the airway is secured, the assessment focuses on conditions preventing effective oxygen exchange. These conditions lead to respiratory failure, which is a leading cause of death following trauma.
Life-Threatening Chest Injuries
A tension pneumothorax occurs when air leaks into the chest cavity, building pressure that collapses the lung and pushes the heart and major blood vessels to the opposite side. This pressure buildup severely compromises both breathing and circulation and requires immediate decompression to release the trapped air.
A massive hemothorax is the accumulation of a large volume of blood, typically over 1,500 milliliters, in the chest cavity, leading to lung compression, severe blood loss, and shock. A flail chest involves multiple ribs broken in two or more places, causing paradoxical movement of the chest wall. This instability impairs ventilation due to underlying lung bruising (pulmonary contusion).
An open pneumothorax (sucking chest wound) is a defect in the chest wall that allows air to enter the pleural space. This condition interferes with the pressure changes needed for normal breathing and must be sealed immediately to restore proper lung function.
Life-Threatening Circulatory Issues
The focus shifts to circulation, where the primary threat is shock, usually hemorrhagic shock from severe blood loss. Assessment involves quickly checking the patient’s pulse quality and rate, skin color, and capillary refill time. A rapid, weak pulse, pale skin, and delayed capillary refill signal inadequate delivery of blood and oxygen to the organs.
The first step is controlling massive external hemorrhage. Direct pressure and the use of tourniquets for severe extremity bleeding are immediate, life-saving measures implemented without delay, often preceding other assessments. Failure to control this visible bleeding significantly increases the risk of death.
Hemorrhagic shock results from losing too much blood volume to maintain adequate tissue perfusion. While external bleeding is obvious, internal bleeding is a common hidden threat, particularly from injuries in the abdomen, pelvis, or large bone fractures. Recognizing signs of shock without an obvious source of bleeding is crucial, as it indicates an ongoing internal hemorrhage requiring urgent surgical or procedural control.
A less common, but equally life-threatening, issue is cardiac tamponade, a non-hemorrhagic form of obstructive shock. Fluid or blood accumulates in the sac around the heart, preventing it from filling properly. This compression rapidly reduces the amount of blood the heart can pump, leading to circulatory collapse.
Rapid Neurological Assessment
The Disability portion is a rapid neurological check identifying immediate threats to the central nervous system, particularly the brain and spinal cord. The level of consciousness is assessed using the AVPU scale, which quickly categorizes the patient as Alert, responsive to Verbal stimuli, responsive only to Painful stimuli, or Unresponsive. Any response less than “Alert” indicates a potential problem related to direct brain injury or poor oxygen/blood flow.
This assessment helps identify signs of increasing pressure within the skull, often caused by an intracranial bleed. Checking pupil size and reaction provides a quick indicator of brain function, as asymmetry or lack of reaction signifies a serious brain injury. It is also important to consider reversible causes of altered mental status, such as low blood sugar (hypoglycemia) or drug intoxication.
Full Body Examination and Environmental Control
The final component, Exposure and Environment, requires completely undressing the patient for a thorough, head-to-toe examination. Full exposure ensures no hidden, life-threatening injuries, such as wounds on the back, armpits, or groin, are missed.
After assessment, the focus shifts to preventing hypothermia, a major complication for severely injured individuals. Trauma patients easily lose body heat, contributing to the “lethal triad” of impaired clotting (coagulopathy) and acidosis. To prevent this, the patient must be covered with warm blankets immediately, and all administered intravenous fluids should be warmed to body temperature.