Anaesthesia for reproductive surgery

Question 1

Why are brachycephalic breeds have a higher risk during GA

Answer 1

Prone to respiratory obstruction, regurgitation and pulmonary aspiration

Question 2

List as many anaesthetic considerations to factor in risk

Answer 2

Age
Brachycephalic
Temperament
Body condition
Analgesia required
Health status

Question 3

Give an example of premed before anaesthesia

Answer 3

Sedative+Opiod
Medetomidine(A2-agonist)+ Methadone/Buprenorphine
IM/IV

Question 4

Give an example of induction before anaesthesia

Answer 4

Propofol
Alfaxalone
Diazepam+Ketamine
IV

Question 5

Give an example of maintenance of anaesthesia

Answer 5

Isoflurane/sevoflurane

Question 6

Suggest appropriate ways to adapt anaesthesia in aggressive or active patients

Answer 6

Select sedative dose rates at higher end of range
Select medetomidine rather than ACP
Combine >1 sedative with opioid
Aggressive: Medetomidine + methadone + low dose ketamine IM

Question 7

Suggest appropriate ways to adapt anaesthesia in Systemically unwell e.g. pyometra (ASA III) patients

Answer 7

Stabilise first, blood testing
Opioid only premedication
Consider co-induction
Aim for “balanced” anaesthesia
Methadone IM/IV midazolam + prop/alfax IV iso/sevo

Question 8

What drug should be given carefully/not given if patient has renal failure

Answer 8

A2 agonist- Reduce renal perfusion

Question 9

Does buprenorphine have a long duration of action

Answer 9

Yep!

Question 10

Name some LA techniques for castration

Answer 10

Intra-testicular block

Question 11

Name some LA techniques for Ovariohysterectomy

Answer 11

Incisional block
Infiltration of ovarian pedicle & neck of uterus
Intraperitoneal lavage

Question 12

Examples of Oral non-steroidal anti-inflammatories 3–5 days

Answer 12

± paracetamol (NOT cats)
± tramadol (cats > dogs ?)
± oral transmucosal buprenorphine (cats > dogs)

Question 13

List 4 COMMON Anaesthetic-related problems

Answer 13

Bradycardia
Tachycardia
Hypothermia
Prolonged or poor quality recovery

Question 14

Common causes of bradycardia during GA

Answer 14

Increased vagal tone
- Alpha2 agonists, opioids
- Athletic young dogs
- Brachycephalic breeds
- Visceral traction
Too deep (or too light?)
Hypothermia
Pre-existing disease

Question 15

Bradycardia: management

Answer 15

What is surgeon doing?
Assess/adjust anaesthetic depth
Consider atipamezole if due to a2 agonist
Administer atropine if systomatic

Question 16

Common causes of tachycardia

Answer 16

Increased sympathetic tone
- Light anaesthesia
- Inadequate analgesia
- Hypovolaemia/hypotension
- Drugs
- Hypercapnia
- Hypoxaemia
- Hyperthermia
Pre-existing disease

Question 17

Tachycardia: management

Answer 17

Address inciting causes:
- What is surgeon doing?
- Assess anaesthetic depth
- Increase vaporiser setting
- Administer rapid onset IV opioid
Symptomatic: Consider a vagomimetic drug Opioid e.g. fentanyl