Shock Flashcards
Types of shock (5)
Hypovolemic/haemorrhagic
Cardiogenic
Obstructive
Neurogenic
Distributive
Cardiac output
= HR x SV
Stroke volume factors
Preload
Myocardial contractility
Afterload
Clinical manifestations of shock
Early:
-tachycardia
-cutaneous vasoconstriction
Evaluate
- RR
- pulse rate and character
- skin perfusion
- pulse pressure
Class II haemorrhage % blood loss
15-30%
Class II haemorrhage signs
Tachycardia, tachypnoea
Dec pulse pressure
Subtle CNS signs eg anxiety, fear
Urinary output 20-30 ml/hr
Base excess -2 to -6
Class III haemorrhage % blood loss
31%-40%
Class III haemorrhage signs
Inadequate perfusion
Marked tachycardia and tachypnoea
Significant changes in mental status
Significant dec in systolic BP
Base deficit -6 to -10
Class IV haemorrhage % blood loss
> 40%
Class IV haemorrhage signs
Marked tachycardia
Significantly decreased systolic BP
Very narrow pulse pressure or unmeasurable diastolic BP
Negligible urinary output
Markedly depressed mental state
Cold, pale skin
Base deficit -10 or more
Confounding factors altering haemodynamic response
Age
Severity of injury
Time between injury -> start of treatment
Prehospital fluid therapy
Medication use
Implanted cardiac devices
Stop the bleeding
Direct pressure
Splint fractures
Tourniquet
Pelvic binder
Operation
Angio embolisation
Gastric distension can cause
Hypotension
Dysrhythmia
Risk of aspiration
Controlled/balance resuscitation
Balancing accepting a lower BP to avoid re bleed
vs
Organ perfusion and tissue re oxygenation
Responses to initial fluid therapy in shock
Rapid response
Transient response
Minimal or no response
Special considerations in shock in the elderly
Inability to inc HR eg on beta blockers
Increased sensitivity of vital organs to reduced blood flow
Pre existing volume depletion (malnutrition, diuretics)
Reduced pulmonary compliance, respiratory weakness
Special considerations in shock in athletes
Increased blood volume
Increased cardiac output
Increased stroke volume
Decreased resting pulse
Increased ability to compensate for blood loss
Special considerations in shock in pregnancy
Normal hypervolemia masks perfusion abnormalities
Possible dec fetal perfusion may indicate maternal hypovolemia
Special considerations: medications in shock
Beta blockers and calcium channel blockers alter haemodynamic response
Insulin - overdose hypo, cause the injury
Long term diuretic therapy leading to hypokalaemia
NSAIDs affect platelets/inc bleeding
Special consideration: hypothermia
Less response to fluid resus
Cause or worsen coagulopathy
