Shock

Shock Evaluation & Management

Definition of Shock A condition that occurs when tissue perfusion with oxygen becomes inadequate. Hypoxia

Normal Perfusion Requires: An intact vascular system Adequate air exchange in the lungs. An adequate volume of blood. A functioning pump - the heart

Hypoxia Anaerobic Metabolism –without oxygen –decreased oxygen to the tissues = tissue death

Hypoxia In response to a lack of oxygen, the sympathetic nervous system releases catecholamines –Fight or Flight Syndrome Catecholamines increase heart rate, constrict blood vessels, increase respiratory rate, stimulate sweat glands.

Major Types of Shock Hypovolemic (absolute) - major body fluid loss. Neurologic (relative) - dilation of blood vessels. Mechanical (obstructive) - certain chest injuries - restricts blood flow Hypoxemic - lung injury, airway obstruction - reduces available oxygen

Hypovolemic Shock The body contains approximately 5 litres of blood Patients can show signs and symptoms of shock with as little as 10% blood loss “Early” vs “Late” Shock

Early Shock 10-15% BREATHING NORMAL RESTLESS NORMAL BLOOD PRESSURE INCREASED HEART RATE PALE

Early Shock 20-25% HYPOTENSION MILD ANXIOUS PALE and SWEATY TACHYPNEIC TACHYCARDIA

Late Shock 30-45% HYPOTENTION TACHYCARDIA CARDIAC ARREST TACHYPNEA EXTREMELY ANXIOUS or UNCONSCIOUS CYANOSIS PROFOUND PALLOR

Neurologic Shock Body loses ability to constrict blood vessels Spinal Shock Head Injury Vasomotor injury from Hypoxia

Obstructive / Mechanical Shock Common in Severe Chest Injuries Slows or Prevents blood flow back to the heart Decreased cardiac output means less oxygen rich blood to cells

Hypoxemic Shock Any condition that prevents the exchange of oxygen / carbon dioxide in the lungs Airway obstruction Pneumonia Smoke Inhalation Aspiration

Signs & Symptoms Tachycardia Tachypnea Pale / Sweaty Thirst Weakness Decreased Level of Consciousness Hypotension Death

Management of Shock C-Spine A B C’s Control Bleeding High Concentration Oxygen Reassess frequently

Summary Shock is often not recognized early enough Careful assessment Mechanism Early signs Adequate oxygenation