Cardiogenic shock

Background

• Leading cause of death in pts w/ MI who reach the hospital alive

Work-Up

• Labs
  • Troponin
  • Lactate
  • CBC
  • Chem
  • BNP
    • <100 may rule-out cardiogenic shock
• ECG
• CXR
• TTE

Etiology

• Myocardial infarction
  • Pump failure
  • Mechanical complications
  • Acute MR (papillary muscle rupture)
  • VSD
  • Free-wall rupture
• RV infarction
• Decreased forward flow
  • Sepsis
  • Rate-related
    • Bradycardia
    • Tachycardia
  • Myocarditis
  • Myocardial contusion
  • Cardiomyopathy
• Mechanical obstruction to forward flow
  • AS
  • HOCM
  • Mitral stenosis
  • Pericardial
• LV regurgitation
  • Chordal rupture
  • Aortic insufficiency

DDX

• MI
• PE
• COPD exacerbation
• Peri/myocarditis
• Aortic dissection
• Pericardial tamponade
• Acute valvular insufficiency
• Sepsis
• Hemorrhage
• Toxins/drugs of abuse

Treatment

• General
  • Intubation
    • Decreases O2 demand BUT may worsen preload
• Coronary perfusion

1. Small Fluid challenge
2. Increase inotropy

• • • Titrate to CO (e.g. warm extremities)
    • Dobutamine or Milrinone - if
      • Use milrinone if pt is on BB
    • CaCl 1gm
      • Give if pt is hypocalcemic

1. Achieve MAP >65

Pressors

Pressor	Initial Dose	Max Dose	Cardiac Effect	BP Effect	Arrhythmias	Special Notes
Dobutamine	2.5mcg/kg/min	10-40 mcg/kg/min	mainly inotrope (ß1)	alpha effect minimal	Some HR(ß1) increase. Also Increase SA and AV node fx	Debut Research 1979
Dopamine	Example	Example	Example	Example	Example	Example
Norepinephrine	Example	Example	Example	Example	Example	Example
Milrinone	50mcg/kg x 10 min	Example	Example	Example	Example	Example
Phenylephrine	100-180mcg/min then 40-60mcg/min	Example	Example	Example	Example	Example
Vasopressin	Fixed Dose	Example	Example	Example	Example	Example

• Transfusion
  • Consider if Hb < 10
• Specific
  • Mitral Regurg
    • Need to increase forward flow
      • Dobutamine (contractility)
      • Nitroprusside (afterload reduction)
  • MI
    • PCI or thrombolysis
  • Tox
    • Reverse CCB, BB, or dig toxicity

See Also

• Shock
• Ultrasound in Shock and Hypotension

Source

Tintinalli

EMCrit Podcast 10