🚑 Initial Shock Management: Oxygen 15 L/min (unless COPD – then 28–35%)
Insert large-bore IV access; send urgent bloods (FBC, U&E, LFTs, clotting, ± lactate, troponin, D-dimer, ABG). Administer oxygen, attach ECG, check troponin and monitor rhythm. Assess fluid status – consider cautious fluid bolus if hypovolaemic. Insert urinary catheter to monitor urine output. If chest pain → ECG & CXR. Assess for STEMI → urgent PCI or thrombolysis. Arrhythmias: Tachyarrhythmia → consider DC shock; Bradyarrhythmia → Atropine/pacing. Assess for acute valve rupture, septal defect, or tamponade → urgent echo + surgical review. Inotropes (Dobutamine ± Dopamine) may be required; intra-aortic balloon pump (IABP) can bridge to revascularisation. Seek senior/ICU support early.

🚑 Initial Shock Management: Oxygen 15 L/min (unless COPD – then 28–35%)

Insert large-bore IV access; send urgent bloods (FBC, U&E, LFTs, clotting, ± lactate, troponin, D-dimer, ABG).
Administer oxygen, attach ECG, check troponin and monitor rhythm.
Assess fluid status – consider cautious fluid bolus if hypovolaemic.
Insert urinary catheter to monitor urine output.
If chest pain → ECG & CXR. Assess for STEMI → urgent PCI or thrombolysis.
Arrhythmias: Tachyarrhythmia → consider DC shock; Bradyarrhythmia → Atropine/pacing.
Assess for acute valve rupture, septal defect, or tamponade → urgent echo + surgical review.
Inotropes (Dobutamine ± Dopamine) may be required; intra-aortic balloon pump (IABP) can bridge to revascularisation.
Seek senior/ICU support early.

💡 In acute coronary syndromes (ACS), reperfusion (PCI > thrombolysis) is the priority. Early revascularisation improves survival and myocardial recovery.

📖 Overview

Cardiogenic shock = inadequate cardiac output → tissue hypoperfusion.
Bedside echocardiography is invaluable (LV function, valves, tamponade).
Primary PCI is the treatment of choice if STEMI or new LBBB present.
Mortality remains high (~70%) without prompt intervention.

⚡ Common Causes

Myocardial: MI (anterior STEMI commonest), ischaemic cardiomyopathy, myocarditis.
Valvular: Acute MR, endocarditis, acute VSD, severe AR.
Toxins: Verapamil overdose, excess β-blockers/negative inotropes.
Arrhythmias: VT, fast AF, complete heart block.
Congenital: CHD in neonates/infants.

🩺 Clinical Presentation

Hypotension: BP < 90/60, weak central pulse, cold extremities, confusion.
Signs of congestion: ↑ JVP (± Kussmaul’s sign), S3, pulmonary oedema, ascites, peripheral oedema.
Arrhythmias: AF, VT, or bradycardia.
Exclude mimics:
- 💨 Tension pneumothorax – unilateral absent breath sounds, tracheal deviation.
- 💔 Tamponade – Beck’s triad (↑ JVP, muffled heart sounds, hypotension), globular heart on CXR, low voltage ECG.

🔍 Investigations

Bloods: Hb (<90 → transfuse), U&E (renal perfusion), LFTs (ischaemia), lactate (tissue hypoperfusion).
ECG: ST elevation, new LBBB, low voltage, posterior MI signs.
Echo: Key test → LV dysfunction, valve rupture, tamponade.
ABG: Hypoxia, metabolic acidosis.
Imaging: CXR (cardiomegaly, pulmonary oedema), CT/MRI (rule out constrictive pericarditis).

⚕️ Management

🌬 Oxygen 15 L/min unless COPD (then 28–35%).
💊 Analgesia for chest pain: Diamorphine/Morphine 2.5–5 mg slow IV.
🫀 ACS: Follow STEMI/NSTEMI pathways → urgent PCI if eligible.
🔄 Arrhythmias:
- Fast AF → Amiodarone 300 mg over 1h or Digoxin if not on it already. Consider DC cardioversion if unstable.
- VT → Amiodarone ± shock if unstable.
💉 Inotropes:
- Adrenaline (1st line) – inotrope + vasoconstrictor.
- Dobutamine/Dopamine in selected cases.
🫀 Mechanical support: IABP (bridge to PCI/surgery), unless AR present.
🩸 Fluids: cautious challenge if wedge pressure < 15 mmHg.
🫗 Insert catheter → monitor urine output.
🏥 Escalate to ICU/CCU early; discuss transplant/mechanical support if refractory.

💊 Drug Actions

Drug	Vasoconstriction	Inotrope	Heart Rate	Vasodilation
Low Dose Dopamine	0	++	++	++
High Dose Dopamine	+++	++	++	++
Low Dose Dobutamine	0	++++	+	++
High Dose Dobutamine	++	++++	+	++
Noradrenaline	++++	++	0	0
Adrenaline	++++	++++	++++	+++

💡 Exam Pearls

Differentiate cardiogenic vs obstructive shock (tamponade, PE, pneumothorax) – management differs.
Mortality high unless rapid PCI/revascularisation achieved.
Look for complications: VSD, papillary muscle rupture, RV infarct.

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Cardiogenic shock