Define shock
Lack of perfusion to tissues, leading to inadequate O2 delivery to vital organs.
Type of shock
Cardiogenic
Hypovolaemic
Distributive
Cardiac output
Volume of blood pumped out of the left ventricle/ min
CO= SV x HR
Factors that affect CO
Preload
- Stretching of ventricles end diastole
Afterload
- Resistance left ventricles have to overcome.
Contractility
Blood pressure
CO x SVR
Consequences of low BP
Brain
- unconsciousness, confusion, delirium
Kidney
- Decreased urine output
Gut
- Necrosis–> perforation–> peritonitis
Heart
- Decreased contractility, cardiac arrest
Skin
- Cold.
Causes of cariogenic shock
- Heart failure
- MI
- Cardiomyopathy/ Valvopathy
- Arrythmia (i.e. AF, VF, VT)
Causes of distributive shock
- Sepsis
- Anaphylaxis
- Neurogenic (loss of autonomic pathway due to spinal cord disruption
Causes of hypovolaemic shock
Dehyradation
Haemorrhagic
Signs of shock
B- High resp rate (24+)/ Increased respiratory effort Low O2 (<95) High lactate (>2), CRP Cyanose
C- Low BP (<80) Decreased Urine output (<0.5ml/kg/hr) Cold, clammy, very warm, red
D
- Decreased GCS/ VPU: drowsy, confused, unconscious
E
- Signs of blood loss
Assessing shock
- LLF
Look - Signs of poor perfusion? Grey, clammy Cyanose V. red? Capillary refill - Respiratory effort Accessory muscles? - Bleeding - Oligouria
Listen - Breathing? Stridor Wheeze/ crepitation - Heart sounds murmur? valve disease - BP?
Feel - Pulse (central and peripheral) Rate? Thready? Arrhythmia? - Temperature - Chest percussion
Initial management of shock
A
- Keep patent
B
- Ventilate if necessary
- High flow O2
C
- Fluid challenge: 10ml/Kg
- Stop bleeding
Reassess interventions
Further management of shock
B
- Chest X-ray
- ABG
C
- ECG
- Bloods: culture, U&Es, group and save
Drugs
- Noradrenaline to increase BP
- Dobutamin to increase contractility AND BP