A&E in anaesthesia Flashcards
Why might you get tachycardia, hypotension and apnoea immediately after propofol administration?
The induction agent was administered too quickly
What should you do next if you get tachycardia, hypotension and apnoea immediately after propofol administration?
Administer 1-2 breaths and give the patient time to start breathing spontaneously
What happens if a capnograph wave does not drop to zero for inspired CO2? What should you do?
the dog is rebreathing –> check the soda lime and the breathing system
What might cause tachycardia one hour into a surgery? 7
- pain
- light anaesthesia
- hypovolaemia
- hypotension
- hypoxaemia
- hypercapnia
- hyperthermia
What should you do to determine why an animal has become tachycardic under GA?
- palpate pulse
- take BP
- look at MM colour
- evaluate blood loss
- evaluate anaesthetic depth
- check pulse oximeter, capnograph, blood gas (O2 and CO2)
How can you estimate blood loss?
- count swabs (hold 5-8ml of blood each)
- DOG = 80-90ml/kg normal blood
- CAT = 60-70 ml/kg normal blood
What might you do in the case of blood loss causing tachycardia under GA? 5
- calculate blood loss
- administer a bolus of crystalloid fluid (if doesn’t work use a colloid, if not give a blood transfusion)
- decrease anaesthetic depth
- switch anaesthesia to a less cardio-depressant drug
- last resort = start a dopamine infusion to increase BP
Why might you have a central eye position and a brisk palpebral reflex?
the depth of anaesthesia is too light (immediate actin = increase the vaporiser setting, then possibly administer more analgesia)
T/F: morphine causes respiratory depression
True
What should you do if you see an overinflated bag?
open the pop-off valve to relieve the pressure
What happens if the pop-off valve is closed? 2
- gas flow from flowmeters has nowhere to escape
- increased intra-thoracic pressure as lungs inflate
What does increased alveolar pressure cause? 4
- compression (collapse) of pulmonary capillaries (reduced preload)
- compression of heart chambers (decreased filling)
- compression of aorta (increased afterload) –> dramatic reduction in CO –> circulatory arrest
- alveolar damage/rupture
What should you check for after increased intra-thoracic pressure? 4
- check for pneumothorax
- check HR goes back up to normal
- check MM, SpO2
- check for other problems too
Why might the SpO2 reading be too low? 3
- there is an obstruction of the ETT (commonest cause in cats because it is a small tube)
- medetomidine-induced vasoconstriction
- anaemia
Why might airway obstruction occur? 3
- kinking of the ETT
- material within the ETT
- overinflation of the tube cuff
- ACTION: remove the ETT to check if obstructed.