Swine Anesthesia Flashcards
Why is anesthesia hard in swine
They can be difficult to handle & restrain (due to body shape and aggression) difficult to intubate, difficult to inject (going into fat not muscle), and some monitoring equipment may not be working properly
Where can you get blood samples from swine
Lateral auricular vein, cranial vena cava, orbital sinus
Where do you admin IM drugs and what makes it better to get appropriate uptake of the drug
Cervical muscle group behind ear
Piglets you can also use the muscles of the thigh
Ensure you use a long enough needle to not be injecting fat but the muscle as infra-fat injections leads to delayed onset/offset
What are some other sites of drug administration
Intranasal
SubQ
Inhalant anesthetics
Are sedatives alone enough for premedication in swine
NO! Must do sedatives + ketamine +/- opioids to induce reliable immobilization
What is an ideal combination of pre-med drugs in swine
Ketamine + alpha 2 +/- (azaperone or midazolam) +/- opioid
Ketamine + detomidine + midazolam
Ketamine + xylazine
Alfaxalone ok for small pigs
What is crucial to give to swine after sedation
Providing O2 via a face mask
When should you place a catheter and where
Only place after adequate chemical restraint
First option can be marginal ear veins
Other options are cephalon vein or saphenous vein
What would you do to induce anesthesia in swine
- Mask induction with sevoflurane when heavily sedated
- Preoxygenate for 3-5 minutes
- Intravenous anesthetics
-propofol +/- ketamine
-titrate IV induction to get a deep plane of anesthesia (stage 3, Plane 3)
Apply topical lidocaine to prevent laryngospasm and making intubation easier
What makes endotracheal intubation hard in pigs
-It can be difficult to visualize epiglottis and arytenoids (thick tongue, elongated soft palate, narrow prop hairy veal space, larynx deep in oral cavity)
-the ET tube can get trapped in pharyngeal diverticulum
-resistance due to the angle between the lateral ventricles and trachea
What anatomical feature do you need to be aware of in pigs when intubating
Pigs have a main bronchus leading into the right cranial lung lobe (Cranial lobe bronchus) BEFORE the tracheal bifurcation
DO NOT WANT to advance ET tube too far into trachea or you can block the right cranial lobe from ventilating
What are some equipment required for a big pig intubation
Long straight miller blade laryngoscope, straight extra long ET tube, lidocaine spray, plastic stylets/bougie
What is your maintenance anesthetics for swine (PIVA OR TIVA)
Inhalant - isoflurane or sevoflurane
Swine triple drip - Guaifenesin, xylazine, ketamine WITH O2 SUPPLEMENTATION
- propofol based cri is possible but has a greater risk of respiratory depression and needs O2 supplementation and mechanical ventilation
Monitoring during anesthesia
-Depth - jaw tone, palpebral and corneal reflex
-Cardio - ECG, non-invasive blood pressure from leg/tail, invasive BP (auricular artery), pulse, MM
-Resp - rate, pulse-ox/blood gas, ETCO2
-Therm - pigs are PRONE TO HYPOTHERMIA but also need to monitor for malignant hyperthermia
What is required for recovery from anesthesia
Extubation after swallowing reflex, place in padded room, recover without other pigs, room temp 20-25C,
INTRANASAL phenylephrine b/c obligate nasal breathers
Post-op analgesia NSAIDs and opioids
