Intraoperative care and support of anaesthetised animal Flashcards
What are the 3 main things part of general care of animal under anaesthesia?
positioning
nursing care
eye care
What does oxygen delivery depend on?
cardiac output and oxygen content
What can potentiallly reduce cardiac output?
extremes of HR
disturbances of rhythm
poor stroke volume (poor ventricular filling, poor contractility, high vasc resistance)
What BPM is considered bradycardia in dogs cats and horses?
dog: under 40 bpm
cats: under 90 bpm
horse: under 25 bpm
What can cause bradycardia?
high vagal tone
electrolye and acid base disturbances (high K+)
\hypothermia
drugs
response to hypertension
bradyarrhythmias
What are the treatments for bradycardia and bradyarrhythmias?
check monitored parameters and anaesthetic depth
remember alpha 2 agonsits associated bradycardia
beware of raised intracranial pressure as a cause
atropine
glycopyrrolate
What bpm is tachycardia in dogs cats and horses?
dog: over 180 bpm
cats: over 220 bpm
horse: over 50 bpm
What can cause tachycardia?
high circulating catecholamines (pain, hypotension, hypovolemia, hypoxia, hypercapnia)
hyperthermia
anaemia
drugs
tachyarrythmias
What is the tx for tachycardia and tachyarrhythmias?
check monitored parameters and anaesthetic depth
rule out or tx underlying cause
What are the 2 types of supraventriclar arrhythmias?
Av block
A fib
How should we treat ventricular arrhythmias in anaesthesia?
tx if haemodynamically significant
assess pulse quality and rate
assess BP
spo2, mm colour, CRT
lidocaine first choice
followed by CRI
cats sensitive to lido tox. may start with b blocker instead
How to tx underlying hypovolemia/hypotension in anaesthesia?
reduce depth of anaesthesia is possible
give IV fluids, bolus if necessary
inotropes/vasopressors
What fluids is common to give during anaesthesia?
crystalloid fluids vs relative hypovolaemia
CSL most common
What fluids do we give for up to 10% blood volume loss?
crystalloid
What fluids do we give for 10-25% blood volume loss?
colloid
What fluids do we give for over 25% blood volume loss?
blood
What is our first step when there is hypotension during anaesthesia whether it is mild or severe?
severe: turn off inhalant agent, consider opioid/ketmaine
mild: turn down inhalant agent, add opioid
What is the inotrope we give to cats and dogs during anaesthesia?
dopamine
What is the inotrope we give to horses duing anaesthesia?
dobutamines
What are the vasopressors we can give to animals during anaesthesia?
noradrenaline
phenylephrine
epherdrine
vasopressin
What is the effect of dopamine?
inotrope
arrhythmogenic
What is the effect of dobutamine?
positive inotropic effect
mild chronotropic
less arrhythmogenic
What is the effect of noradrenaline?
vasopressor
b1 and a1 adrenergic effecr
positive inotrope
increase CO and SVR
reduced liver muscle renal and skin perfusion
What is the effect of phenylephrine?
vasopressor
a1 adrenergic effect
increase SVR
reduced splanchnic perfusion
What is the effect of ephedrine?
vasopressor
stimulates endogenous noradrenaline release
a and b adrenergic effect
reduced splanchnic and renal perfusion
increased HR, MAO, CO
WHat is the effect of vasopressin
potent vasopressor on V receptors
increased SVR
reduced splanchnic perfusion
What can cause hypercapnia/hypercarbia?
hypoventilation
rebreathing of exhaled gas
increased BMR
What can cause hypoxaemia and hypoxia?
decreased FiO2
hypoventilation
v/q mismatch
CV depression
diffusion barrier
anaemia
increased O2 demand
How can we help in cases of hypoxaemia and hypercapnia during anaesthesia?
check anaesthetic depth
check airway
increase FiO2 if possible
ensure no rebreathing of CO2
ventilate
consider PEEP
