Key Takeaways
- Shock (hypoperfusion) is inadequate tissue perfusion resulting in insufficient oxygen delivery to cells, and it can be fatal if not recognized and treated promptly
- The four main categories of shock are hypovolemic (blood/fluid loss), cardiogenic (pump failure), distributive (vasodilation), and obstructive (mechanical obstruction)
- Compensated shock presents with tachycardia, pale/cool skin, and anxiety while maintaining a near-normal blood pressure; decompensated shock shows falling blood pressure and altered mental status
- In pediatric patients, tachycardia is the earliest and most reliable sign of shock; hypotension is a LATE and ominous finding indicating decompensation
- Distributive shock includes septic shock (warm/flushed skin initially), anaphylactic shock (urticaria, bronchospasm), and neurogenic shock (warm/dry skin below injury, bradycardia)
- EMT treatment for shock includes positioning the patient supine, maintaining body temperature, administering high-flow oxygen, and providing rapid transport to a trauma or appropriate facility
- Cardiogenic shock presents with signs of heart failure including jugular vein distension (JVD), pulmonary edema, and chest pain
Shock Recognition & Management
Shock (hypoperfusion) is a life-threatening condition in which the cardiovascular system fails to deliver adequate oxygen and nutrients to the body's cells. Without treatment, shock progresses from compensated to decompensated to irreversible, ultimately leading to death.
Understanding Perfusion
Adequate perfusion requires three components working together:
- Pump - A functioning heart
- Container - Intact blood vessels with appropriate tone
- Fluid - Adequate blood volume
If any one of these components fails, shock can develop.
Types of Shock
| Type | Cause | Pump/Container/Fluid | Examples |
|---|---|---|---|
| Hypovolemic | Loss of blood or fluid | Fluid problem | Hemorrhage, burns, dehydration, vomiting/diarrhea |
| Cardiogenic | Heart pump failure | Pump problem | MI, heart failure, dysrhythmias, myocarditis |
| Distributive | Widespread vasodilation | Container problem | Septic, anaphylactic, neurogenic |
| Obstructive | Mechanical obstruction | Pump/container problem | Tension pneumothorax, cardiac tamponade, pulmonary embolism |
Distributive Shock Subtypes
| Subtype | Cause | Unique Signs |
|---|---|---|
| Septic | Severe infection | Early: warm, flushed skin (warm shock); Late: cool, pale skin (cold shock); fever, tachycardia |
| Anaphylactic | Severe allergic reaction | Urticaria (hives), angioedema, bronchospasm, wheezing, hypotension, itching |
| Neurogenic | Spinal cord injury (typically above T6) | Warm, dry, flushed skin below injury; bradycardia (loss of sympathetic tone); hypotension |
Compensated vs. Decompensated Shock
The body has mechanisms to maintain blood pressure even when perfusion is compromised. Recognizing early (compensated) shock can save lives.
| Sign | Compensated Shock | Decompensated Shock |
|---|---|---|
| Blood pressure | Normal or slightly low | Falling / frankly hypotensive |
| Heart rate | Tachycardia (early sign) | Marked tachycardia or bradycardia (terminal) |
| Mental status | Anxious, restless, agitated | Altered, confused, unresponsive |
| Skin | Pale, cool, diaphoretic | Mottled, cyanotic, cold |
| Capillary refill | Delayed (>2 seconds) | Significantly delayed (>4 seconds) |
| Urine output | Decreased | Minimal or absent |
| Respiratory rate | Increased (tachypnea) | Irregular, shallow, or agonal |
Key concept: A normal blood pressure does NOT mean the patient is not in shock. The body compensates to maintain BP until it can no longer keep up, at which point the patient rapidly deteriorates.
Skin Signs in Shock
Skin assessment is one of the fastest ways to evaluate perfusion:
| Skin Finding | Indicates |
|---|---|
| Cool, pale, diaphoretic | Hypovolemic or cardiogenic shock (sympathetic response) |
| Warm, flushed (early) | Septic shock (vasodilation) |
| Warm, dry below injury | Neurogenic shock (loss of sympathetic tone) |
| Urticaria (hives), flushed | Anaphylactic shock |
| Mottled, cyanotic | Late/decompensated shock (any type) |
Pediatric Shock Considerations
Children compensate for shock differently than adults:
- Tachycardia is the EARLIEST and most reliable sign of shock in children
- Children maintain blood pressure longer than adults through increased heart rate and vasoconstriction
- Hypotension in a child is a LATE and ominous sign indicating the child has exhausted compensatory mechanisms
- Once a child becomes hypotensive, cardiovascular collapse can occur rapidly
- Minimum systolic BP formula for children 1-10 years: 70 + (2 x age in years) mmHg
- Signs of poor perfusion: prolonged capillary refill (>2 sec), weak/thready pulses, altered mental status, decreased urine output
Trendelenburg Position Considerations
The Trendelenburg position (legs elevated) has been traditionally used for shock but current evidence is mixed:
- May provide temporary benefit by increasing venous return
- Elevating the legs 6-12 inches (modified Trendelenburg) is generally preferred
- Contraindicated in patients with head injuries, respiratory distress, or suspected spinal injuries
- Not a substitute for fluid resuscitation and definitive care
EMT Treatment for Shock
- Ensure scene safety and use appropriate PPE
- Manage the ABCs - Airway, breathing, circulation
- Control external bleeding if present
- Position the patient - Supine; elevate legs if no contraindication
- Maintain body temperature - Cover with blankets, prevent hypothermia
- Administer high-flow oxygen (15 L/min via non-rebreather mask)
- Do NOT give anything by mouth (patient may need surgery)
- Monitor vital signs frequently (every 5 minutes for unstable patients)
- Provide rapid transport to the appropriate facility
- Provide reassurance to the conscious patient
Which type of shock is caused by a severe allergic reaction resulting in widespread vasodilation and bronchospasm?
What is the earliest and most reliable sign of shock in a pediatric patient?
A patient with a spinal cord injury at C6 presents with warm, dry skin below the injury level, hypotension, and a heart rate of 52 bpm. What type of shock is most likely?
Which of the following is a sign of COMPENSATED shock?
A patient is in shock from a severe hemorrhage. What is the appropriate EMT treatment?
Which three components are required for adequate tissue perfusion?
Match each type of shock to its classic presentation:
Match each item on the left with the correct item on the right