Trauma
Primary survey and hemorrhage
Trauma care follows a fixed sequence: catastrophic hemorrhage control, airway, breathing, circulation, disability, exposure/environment. The leading preventable cause of early death is uncontrolled bleeding, so apply direct pressure, then a tourniquet (2–3 inches above the wound, never over a joint) for life-threatening extremity hemorrhage, or a junctional device or wound packing for neck, axilla, and groin. Note the tourniquet time and do not loosen it in the field.
Thoracic and abdominal trauma
Suspect tension pneumothorax with unilateral absent breath sounds, severe dyspnea, hypotension, and distended neck veins; it is a clinical diagnosis and needle decompression is the treatment. Cover an open chest wound with a vented seal. Flail chest is managed with oxygen, positioning, and positive-pressure support, not binding. Eviscerations are covered with a moist sterile dressing - never push organs back in.
Head and spinal injury
Prevent secondary brain injury: oxygenate, maintain blood pressure, avoid hyperventilation unless there are signs of herniation, and keep the head neutral. Spinal motion restriction is applied based on mechanism and findings, not to every trauma patient by default.
Trap: 'sucking chest wound' questions often offer dressings that seal all four sides; a fully occluded wound can convert a simple pneumothorax into a tension pneumothorax.
Rule of thumb: in trauma with hypoperfusion, control the bleeding before you worry about fluid. Permissive hypotension (systolic near 90 mmHg) is acceptable in penetrating trauma without head injury.
Burns: estimate with the rule of nines (each arm 9%, each leg 18%, anterior trunk 18%, posterior trunk 18%, head 9%) and treat for associated inhalation injury.