Anesthesia for Pigs and Ruminants Flashcards
What are examples of extra label drug use?
Human labeled drugs in animals (diazepam, midazolam)
Use in a non-approved species (xylazine, dexmedetomidine, telazol, propofol, ketamine, sevoflurane)
Approved for a species, but used in an non-labeled indication or dose
When do we use extra-label drugs in food animals?
Make an accurate diagnosis within the context of a VCR
Assure no labeled drug is available or appropriate for the circumstance
Positively identify the treated animal
Supply withdrawal info to the client in writing
Why is general anesthesia not used often for swine and ruminants?
Cost/residue issues
What are the reasons for general anesthesia in pigs?
Foot trims/teeth Lameness OHE/castration Diagnostics Exploratory laparotomy Radiation treatment Research
What are anesthetic concerns in pigs?
Prone to laryngospasm
Long floppy epiglottis, poor laryngeal visualization
Ventral laryngeal diverticulum
Small tracheal diameter for size and weight
Limited IV access
Respiratory depression common
Low surface area to body mass, poor thermoregulatory function- easy to overhear
Variable responses
How should you prep a swine patient?
Withhold food 4-6 hours and water 1 hour
Preoperative abnormalities should be corrected prior to anesthesia
Consider pre-emptive analgesia
Minimize anesthesia time
What veins can you access in pigs?
Marginal ear veins Cephalic veins Lateral or medial saphenous vein Cutaneous epigastric veins Jugular vein in young animals
What is piggy magic?
Dexmedetomidine (20-40 mcg/kg IM)
Butorphanol (0.2 mg/kg IM)
Ketamine (10-20 mg/kg IM)
Option: glycopyrrolate (0.01 mg/kg IM)
What dose can telazol be used as a premed?
1-5 mg/kg IM
What is telazol associated with?
Prolonged and/or rocky recoveries
What is generally the best for anesthetic maintenance?
Inhalants
Iso or sevo
Can be administered by mask, but endotracheal intubation is safest
What can all volatile anesthetics trigger?
Malignant hyperthermia/porcine stress syndrome
What are signs of pain in pigs?
Increased tolerance to handling Reluctance to stand or move Lameness Inappetence Shivering, piloerection Short, high pitched grunts when forced to move Tucked up abdomen
What can be used for postoperative analgesia?
Butorphanol (0.1 mg/kg IM, IV)
Buprenorphine (0.005-0.02 mg/kg IM, IV)
Carprofen (2-4 mg/kg SQ or IV, up to 3 days)
Flunixin (1-2 mg/kg SQ, IV, up to 3 days)
Ketoprofen (3 mg/kg IM, once)
What is malignant hyperthermia/porcine stress syndrome?
Single point pharmacogenetic defect in the ryanodine gene (HAL 1843 dm) affecting Ca transport into muscle cells
What pig breeds have MH/PSS?
Heavily muscled breeds
What is PSS triggered by?
Stress, high environmental temps, exercise, mating, fighting
What is MH triggered by?
Volatile anesthetics, depolarizing muscle relaxants, caffeine
True or false: HAL 1842 dm is rare in potbellied pigs
True
What are signs of acute MH/PSS?
Spiking body temp Tachycardia Tachypnea O2 desaturation and cyanosis Hypercarbia with rapid color change and heating of CO2 absorber Met acidosis Skeletal muscle rigidity Blotchy mottling of skin
When can pigs get hot without MH/PSS?
Stressed
During physical exertion/shipping
Placed in a hot environemnt
What do anesthetics inhibit?
Hypothalamic thermoregulation
How can you treat MH/PSS?
Discontinue inhaled anesthesia
Dantrolene 1-3 mg/kg IV push
What are the short term side effects of dantrolene?
Muscle weakness (exacerbated by concomitant tranquilizer or neuromusclar blocker administration)
What are the long term side effects of dantrolene?
Hepatitis, seizures, pleural effusion with pericarditis
What are the reasons for general anesthesia in ruminants?
Urinary obstruction/ruptured bladder Abdominal exploratory Rumenotomy for grain overload C-section Research
What does electroimmobilization cause?
Conscious paralysis and aversive recall. No analgesia
What are the anesthetic concerns of ruminants?
Difficulty visualizing arrytenoids- unable to open mouth wide
Reflex regurgitation can result in aspiration pneumonia
Bloat likely with prolonged recumbence
Profuse salivation
What should be done to prepare ruminants for procedures?
Withhold feed 8-12 hours, water 8-12 hours
Consider pre-emptive analgesia
Minimize anesthesia time
What can be used for premeds in ruminants?
Midazolam + butorphanol
Alpha-2 agonists (dexmedetomidine, xyalzine)
How can you reverse alpha-2 agonists?
Atipamezole
What are α2s associated with?
Hyperglycemia Diuresis Bloat Pulmonary hypertension Pulmonary edema Hypoxia
What can be used for induction in ruminants?
Propofol
Midazolam + ketamine
Xylazine + ketamine
Telazol
How are stun techniques done?
IV or IM induction with an injectable anesthetic
What are stun techniques used for?
Short duration procedures
What must be used in stun techniques?
A drug that produces unconsciousness
What is used for anesthetic maintenance in ruminants?
Inhalants
Propofol
Sheep/goat: 5% guaifenesin solution with xylazine and ketamine
What makes llamas unique?
Obligate nose breathers
Elevated base of tongue
Nasopharyngeal diverticulum
Constrictive palatopharyngeal arch at the end of the soft palate forms an ostium
Epiglottis and arytenoid cartilages protrude through intrapharyngeal ostium into nasopharynx
What is required for endotracheal intubation of camelids?
350 mm laryngoscope or endoscope
What are signs of ruminant pain?
Vocalization Teeth grinding Lack of cudding Inappentance Flank watching/kicking Tachycardia Tachypnea
What was the first drug approved for pain control in livestock?
Transdermal flunixin
True or False: phenylbutazone is approved for use in food-producing animals
False, only approved for dogs and horses
In what age dairy cattle is phenylbutazone banned by the FDA?
> /= 20 months
