What is the management of cardiogenic shock?

Management of Cardiogenic Shock

Cardiogenic shock requires immediate intervention with fluid challenge (if no volume overload), followed by dobutamine as first-line inotropic support, norepinephrine as the vasopressor of choice for persistent hypotension, and early transfer to a tertiary center for possible mechanical circulatory support and revascularization. 1

Diagnosis and Initial Assessment

• Rapidly evaluate with:

  • ECG and echocardiography
  • Invasive monitoring with arterial line
  • Assessment for signs of hypoperfusion:
    • Oliguria
    • Cold extremities
    • Altered mental status
    • Lactate >2 mmol/L
    • Metabolic acidosis
    • SvO₂ <65% 1

• Diagnostic criteria:

  • Hypotension (SBP <90 mmHg for >30 minutes)
  • End-organ hypoperfusion
  • Elevated lactate (>2 mmol/L)
  • Cardiac index <1.8-2.2 L/min/m²
  • Pulmonary capillary wedge pressure >15 mmHg 1

Treatment Algorithm

Step 1: Volume Assessment and Management

• If no signs of volume overload: Administer fluid challenge (saline or lactate solution, >200 ml/15-30 min) 1
• If signs of volume overload present: Skip to inotropic support

Step 2: Inotropic Support

• First-line inotrope: Dobutamine 2-20 μg/kg/min IV to increase cardiac output 1
• For patients on chronic beta-blockers: Consider levosimendan 1

Step 3: Vasopressor Support (if hypotension persists)

• Vasopressor of choice: Norepinephrine
  • Dilute 4 mg in 1000 ml of 5% dextrose
  • Start at 8-12 μg/min and titrate to response 1, 2
  • Target MAP 70-100 mmHg (in previously hypertensive patients, aim for no more than 40 mmHg below baseline systolic pressure) 2

Step 4: Mechanical Circulatory Support

• Consider for refractory shock based on:

  • Patient age
  • Comorbidities
  • Neurological function 1

• Device selection based on failure pattern:

  • Left ventricular failure: Impella devices, IABP, or TandemHeart
  • Right ventricular failure: Impella RP or TandemHeart Protek-Duo
  • Biventricular failure: Bilateral Impella pumps or VA-ECMO with LV venting 1

• Note: IABP is not recommended for routine use due to lack of survival benefit 1

Step 5: Revascularization

• All patients should be rapidly transferred to a tertiary center with 24/7 cardiac catheterization and ICU capabilities 1
• Early revascularization should be considered in selected patients with shock developing within 36 hours of myocardial infarction 1
• Culprit-lesion revascularization is preferred over multivessel PCI in AMI-related shock 3

Management Targets

• Cardiac index: ≥2.2 L/min/m²
• Mixed venous oxygen saturation: ≥70%
• Mean arterial pressure: ≥70 mmHg
• Urine output: >30 mL/h
• Lactate clearance 1

Additional Considerations

Respiratory Support

• Consider early endotracheal intubation and mechanical ventilation to:
  • Reduce work of breathing
  • Improve oxygenation and acid-base status
  • Facilitate revascularization procedures 1, 4

Multidisciplinary Approach

• Implementation of a multidisciplinary shock team approach has been associated with improved 30-day all-cause mortality (HR, 0.61; 95% CI, 0.41–0.93) 1

Medication Discontinuation

• Avoid abrupt withdrawal of vasopressors
• Gradually reduce infusions once adequate blood pressure and tissue perfusion are maintained 2

Important Pitfalls to Avoid

1. Overlooking occult hypovolemia: Always suspect and correct occult blood volume depletion when high doses of vasopressors are required 2

2. Delayed revascularization: Early revascularization is critical for AMI-related cardiogenic shock 1, 3

3. Inappropriate device selection: Match mechanical support device to the specific ventricular failure pattern 1

4. Failure to recognize and address the vicious cycle: Cardiogenic shock involves a spiral of ischemia causing myocardial dysfunction, which further worsens ischemia 5

5. Overlooking patient preferences: Consider patient wishes regarding mechanical ventilation and invasive mechanical support before escalation 1