Emergencies

Question 1

Shock

Answer 1

Circulatory failure, inadequate organ perfusion
BP <90mmHg or MAP <65mmHg with tissue hypoperfusion e.g. mottled skin, UO <0.5 mL/kg/h serum lactate >2

Signs: reduced GCS, cool peripheries, tacyhycardia, tachypnoea

MAP = CO X TPR (total peripheral resistance)
CO = SV X HR
Shock can be due to decreased CO or TPR or both

Decreased CO
Causes:
Hypovolaemia, bleeding
ACS, arrythmia, PE (cardiogenic shock), tension pneumothorax

Loss of TPR
Causes: sepsis (infection can cause acute vasodilation) , anaphylaxis, neurogenic (SC injury)

Ix:
A-E
2 large-bore IV access
ECG

Septic shock - warm, well-perfused, signs of source of infection
Tx: sepsis 6

Cardiogenic - Cold, clammy, raised JVP
Causes: ACS, arrythmia, PE, cardiac tamponade
Ix: ECG, troponin, ABG, CXR, echo
Tx: plasma expander (if under-filled), if over-filled (ionotropic support e.g. dobutamine)

Anaphylaxis - wheeze, rash/uticaria, hypotension, flushing, stridor
Tx: IM adrenaline 0.5MmL 1:1000, IV chloramphenamine, IV hydrocortisone

Hypovolaemic shock - pallor, decreased JVP, orthostatic hypotension
Tx: raised legs, IV crystalloid (large peripheral line)

Haemorrhagic shock
Tx: 2L crystalloid, crossmatch blood, FFP +red cells (1:1 ratio), platelets, tranexamic acid

Question 2

Diff types of shock

Answer 2

Hypovolaemic shock - not enough circulatory vol

Distributive - septic (infection causes end organ damage and blood vessel damage (refractory hypotension so doesn’t respond to IV fluids), neurogenic shock (loss of symp activation leads to vasodilation, anaplylactic (systemic vasodilation leading to hypotension)

Cardiogenic -heart not pumping blood properly. Due to MI, HF

Obstructive - obstruction of blood flow inside/outside heart. Due to cardiac tamponade, PE, pneumothorax