Cardiogenic shock

Question 1

What is cardiogenic shock?

Answer 1

Systolic BP < 90 mm Hg with urine output < 20 mL/hr and normal or elevated left ventricular filling pressure

Question 2

What are the causes of cardiogenic shock?

Answer 2

(Non-obstructive) Myocardial infarction 
Arrhythmias
(Obstructive) Tension pneumothorax
Cardiac tamponade
Constrictive pericarditis
Restrictive cardiomyopathy
Pulmonary embolism

Question 3

What are the clinical features of cardiogenic shock?

Answer 3

Weak pulse, tachycardia
Cold, clammy extremities, poor capillary refill
Dyspnea, fine basal crepitations 
Elevated JVP and distended neck veins
Hypotension with a narrow pulse pressure

Question 4

How is cardiogenic shock diagnosed?

Answer 4

Cardiac markers for acute coronary syndrome (e.g., ↑ troponin I, troponin T)
ECG for MI/arrhythmia
Echocardiography for valve lesions, tamponade
CXR, ABG, U&E

Question 5

What is the treatment of cardiogenic shock?

Answer 5

(Myocardial infarction) Norepinephrine or dophamine, reperfusion therapy, vasodilators (e.g. hydralazine, isosorbide dinitrate)
(Cardiac tamponade) pericardiocentesis
(Pulmonary embolus) thrombolysis
(Tension pneumothorax) needle decompression