1 Shock Recognition and Initial Assessment

Recognize impaired perfusion

Shock is a life-threatening state of inadequate tissue perfusion. Blood pressure may remain normal early because the body compensates, so do not wait for hypotension when mental status, skin perfusion, pulses, or urine output are worsening.

Warning signs can include tachycardia, tachypnea, confusion, cool or mottled skin, delayed capillary refill, weak pulses, and reduced urine output. Findings vary with the cause and stage of shock. Interpret vital signs alongside the history and the overall assessment rather than relying on any one finding.

Use a focused ABCDE assessment

Use an ABCDE approach while arranging emergency help and beginning resuscitation under local protocols. Establish monitoring and intravenous or intraosseous access as appropriate, reassess frequently, and investigate the likely cause.

• Airway and breathing: Assess airway protection, respiratory effort, oxygen saturation, and signs of respiratory distress.

• Circulation: Check heart rate and blood pressure trends, pulse quality, skin temperature and color, capillary refill, and possible bleeding.

• Disability: Assess alertness and changes in mental status; check glucose when indicated.

• Exposure: Look for bleeding, trauma, rash or hives, sources of infection, and signs suggesting chest or cardiac emergencies. Prevent heat loss.

A rising lactate can support concern for tissue hypoperfusion, but no single vital sign, laboratory result, or physical finding identifies shock on its own.

Distinguish major shock patterns

The major shock patterns point to different underlying problems, but their findings can overlap. For example, a patient with sepsis may also be volume depleted or have impaired heart function.

• Hypovolemic shock: Too little circulating volume. Possible clues include bleeding, vomiting, diarrhea, burns, or dehydration; cool skin, weak pulses, and delayed capillary refill may also occur.

• Cardiogenic shock: The heart cannot pump enough blood. Chest discomfort, cardiac history, or an abnormal rhythm may be clues. Crackles, breathlessness, or signs of fluid backing up into the lungs may occur.

• Distributive shock: Blood vessels dilate and distribute blood abnormally. Warm or flushed skin and bounding pulses may occur, especially early. Causes include sepsis, anaphylaxis, and neurogenic injury.

• Septic shock: Distributive shock caused by infection and a dysregulated response. Suspected infection with altered mental status, fast breathing, low blood pressure, or other perfusion problems is concerning. Skin may be warm early and cool later.

• Obstructive shock: A mechanical problem blocks heart filling or blood flow. Sudden deterioration may raise concern for tension pneumothorax, cardiac tamponade, or a large pulmonary embolism. Neck-vein or breath-sound findings may help, but their absence does not rule it out.

Connect assessment findings to urgent action

Treat suspected shock as an emergency and support the patient while pursuing cause-directed care. A serious injury followed by pallor, sweating, confusion, tachycardia, and hypotension is concerning for hemorrhagic hypovolemic shock. Priorities include supporting ABCs, rapidly identifying and controlling bleeding, and activating emergency trauma care; do not wait for laboratory confirmation or delay care for oral fluids and later reassessment.

Chest pressure followed by hypotension, confusion, shortness of breath, crackles, and cool extremities suggests a cardiogenic pattern. Sudden hypotension with hives, wheezing, and facial swelling after a medication strongly suggests anaphylactic distributive shock. Activate the emergency response and follow the applicable anaphylaxis protocol.

Sudden severe shortness of breath and hypotension after chest trauma, with markedly reduced breath sounds on one side, raises concern for an obstructive cause such as tension pneumothorax. Urgently identify and treat the suspected mechanical cause under emergency protocols; do not delay immediate indicated treatment for routine testing.

Respond to possible sepsis-related shock

Suspected infection with new confusion, rapid breathing, low blood pressure, and a lactate above the reference range is an emergency, even if fever is absent. Initiate urgent assessment and resuscitation, obtain cultures when feasible without delaying indicated antibiotics, and reassess perfusion.

Lactate can help assess risk and trends, but an elevated result alone does not prove septic shock. Do not wait for culture results before considering antibiotics when treatment is indicated.

Apply the recognition principles

A normal-range systolic blood pressure does not exclude early shock. For example, restlessness and thirst after several days of vomiting, with a heart rate of 122 per minute, a respiratory rate of 26 per minute, blood pressure of 108 over 72 mm Hg, cool hands, and delayed capillary refill suggest impaired perfusion and possible early hypovolemic shock.

Recognize shock by evidence of inadequate perfusion, not by blood pressure alone. Use the history and focused assessment to identify likely volume loss, pump failure, vasodilation, infection-related dysfunction, or mechanical obstruction. Begin emergency support and cause-directed care promptly, and reassess trends in mental status, vital signs, skin perfusion, pulses, and urine output.