Anaesthesia

Question 1

what effects does general anaesthesia have on the cardiovascular system?

Answer 1

negatively inotropic - decreases strength of contractions

decreases vasoconstrictor tone - vasodilatation = hypotension

venodilatation = decreases venous return = decrease cardiac output

Question 2

what effects does general anaesthesia have on the respiratory system?

Answer 2

decreases FRC;
decreases lung volume
causes V/Q mismatch

respiratory depressants: decrease hypoxic and hypercarbic drive
decrease tidal volume and increase respiratory rate

paralyse cilia

Question 3

why does some patients require post op oxygen after surgery?

Answer 3

general anaesthesia causes decrease in FRC which can cause V/Q mismatch

this V/Q mismatch can persist into the post-op period up to several days

Question 4

what’s the difference in the respiratory depression caused by opitaes vs general anaesthesia?

Answer 4

opiates cause rep depression by: maintaining tidal volume but decreasing respiratory rate

G.A. causes resp Depression by decreasing tidal volume and increasing resp rate

Question 5

when would you intubate a patient when under general anaesthesia?

Answer 5

when they require muscle relaxant for surgery i.e. abdominal surgery

protects airway from gastric secretions - emergency surgery in unfasten patient

need for tight control of blood gasses - neurosurgery

restricted access to airway - maxfax surgery

shared airway with risk of contamination - ENT surgery

Question 6

what airway maintenance provides a protected airway?

Answer 6

endotracheal tube