Flashcards in Haemorrhage & Shock Deck (21):
What is meant by circulatory shock?
When the cardiovascular system is unable to provide adequate oxygen & nutrients for aerobic cellular respiration
What are the signs of shock?
Pale, cold, sweaty, mottled skin
Pulse is weak and rapid
Pulse pressure is reduced
Slow capillary refill
Urine output is reduced
What are they types of shock?
What is hypovolaemic shock?
Severe blood or fluid loss meaning the heart can't pump enough blood around the body
What causes hypovolaemic shock?
- acute GI bleed
- Peri/post operative
- Splenic rupture
What is cardiogenic shock?
Inadequate tissue perfusion caused by cardiac pump failure
What causes cardiogenic shock?
Arrhythmia: V fib, etc
Tension pneumothorax: pressure on mediastinum = no venous return to heart
Anything that causes pump failure
How does sepsis cause shock?
Inflammatory response to bacteraemia
Histamine, NO, other inf mediators released
Affects small blood vessels
Vasodilation, leaky capillaries
Reduced blood volume
Coagulation cascade is disrupted which leads to DIC
What is DIC?
Disseminated intravascular coagulation
Bacteraemia or trauma causes inappropriate widespread activation of coagulation cascade, formation of loads of blood clots in small vessels
Leads to the compromise of blood flow to tissue and organs
Since clotting factors and platelets are used up by the clots you get bleeding as well
How does anaphylaxis cause shock?
Massive histamine release causes systemic vascular dilatation and leaky capillaries
Causing a hypovolaemia, hypotension
What is neurogenic shock?
Injury to the CNS which causes loss of vascular tone, so blood flow is altered
I.e spinal injury?
How would you manage septic shock?
Oxygen (HF, NRB mask)
How would you manage anaphylactic shock?
Give IM adrenaline (epipen)
How would you treat hypovolaemic shock?
If haemorrhagic, give blood
What are other symptoms of anaphylactic shock?
Why does shock cause low BP?
Reduction in ventricular filling = fall in stroke volume + therefore BP
Why does shock cause oliguria?
Reduced renal perfusion, reduced glomerular filtration
What does ARDS stand for?
Acute respiratory distress syndrome
What is ARDS?
Widespread inflammation in the lungs triggered by trauma, sepsis, etc.
Inflammation causes alveolar capillary membrane injury
Leading to impaired gas exchange in the lungs, so the body does not get enough oxygen
What are the clinical features of ARDS?
Bi-lateral fine inspiratory crackles