shock Flashcards
define shock
Acute circulatory failure with inadequate or inappropriately distributed tissue perfusion
(meaning there is inadequate glucose and oxygen for aerobic cellular respiration),
resulting in generalised hypoxia and/or inability of cells to utilise oxygen.
describe blood pressure in shock
Low BP – systolic <90 mmHg
presentation of shock
- Skin is pale, cold, sweaty and vasoconstricted
- Rapid, weak pulse
- Reduced pulse pressure
- Reduced urine output
- Confusion, weakness, collapse and coma
- Capillary refill time (CRT)
is arertial blood pressure a good indicator. ofshock
no because it will be maintained until a very large amount of blood loss
Reduced urine output
how does capillary refill time indicate shock
if it takes more than 3 seconds to turn pink after 5 seconds of compression
this is the earliest and most accurate sign of shock
types of shock
- septic
- hypovalaemic
- anaphylactic
- cardiogenic
- neurogenic
what is septic shock
infection with any organism
acute vasodilation from inflammatory cytokines
what is anaphylactic shock
Type-I IgE-mediated hypersensitivity, release of histamine
what is neurogenic shock
spinal cord injury, epidural or spinal anaesthesia
what is hypovalaemic shock
loss of >20% of body’s blood or fluid supply, severe fluid loss makes it impossible for the heart to pump a sufficient amount of blood around the body
what is cardiogenic shock
happens when your heart cannot pump enough blood and oxygen to the brain and other vital organs
2 types of hypovalaemic shock
- Haemorrhage
- Non-haemorrhagic (fluid loss)
4 haemorrhage causes of hypovalaemic shock
Trauma
GI bleeding
Fractures
Ruptured aortic aneurysms
4 non haemorrhagic causes of hypovalaemic shock
Burns – heat increases permeability of capillaries so more plasma leaks
Severe diarrhoea and vomiting 🡪 dehydration
Intestinal obstruction (fluid accumulates in intestines)
Pancreatitis
cardiogenic causes of shock
Acute MI
Myocarditis
Atrial and ventricular arrhythmias
Bradycardias
Rupture of valve cusp
Obstructive
