AVIAN ANESTHESIA & SURGERY

1. AVIAN ANESTHESIA & SURGERY Kim Healy VETS 247 – Exotic Animal Medicine and Nursing Dr. Meckel Spring 2008

2. Anesthetic Procedures • Surgical sexing • Not as commonly done now • DNA testing • Abscess/Wound repair • Repair bone fractures • Foreign body removal • Growth removals

3. Anesthetic Procedures • Radiography • Endoscopy • Repair beak abnormalities • Scissor beak • Reproductive problems • Egg-bound • Many more

4. Preanesthetic Period • Complete History • Physical Exam • Diagnostics • CBC/Chem • +/- Radiographs or Ultrasound • Stabilization for critical patients • Fasting: 0-2 hours prior to procedure

5. Premedication • Rarely used • Stress from handling • Unpredictability of injectable drugs • Anticholinergics (Atropine, Glycopyrrolate) • If history of bradycradia • Opioids (Butorphanol) • Reversible

6. Induction • Inhalants – preferred method • Isoflurane or Sevoflurane • Iso: less cardiac s/e • Benefits • Rapid induction and recovery • Rapid adjustments to anesthetic depths • Low organ toxicity

7. Induction • Injectables • Unpredictable effects • Side effects • Extended recovery times • Ketamine +/- Benzodiazepines • Long & stormy recovery • Propofol • Respiratory depression • Stormy recovery

8. Induction • Mask • Commercially made • Home made • Plastic bottles or syringe cases • Smaller patients • Whole head inside mask

9. Intubation • Can use mask for very short procedures • Intubation provides: • Manual ventilation • Prevents aspiration • Non-rebreathing system • Less than 7kg

10. Intubation • Concentric (complete) tracheal rings • Less flexible • Don’t inflate cuff of endotracheal tube • Or, use uncuffed tubes • Cole • Inflated cuff can cause pressure necrosis of trachea and sloughing of mucosa

11. Intubation

12. Intubation • Air sac cannula • Head/beak procedures • Clearing tracheal obstruction • Caudal thoracic air sac • Through lateral body wall • Typically left side – larger air sac • Can be left in for several days • E-collar

13. Air Sac Cannulation

14. Local Anesthesia • Example – Lidocaine • Not recommended • Necessary dose higher than toxic dose, especially in smaller birds • Restraint of an awake bird is difficult

15. Surgical Prep • Avoid heat loss! • High surface area to volume ratio = lose heat quickly • Pluck only necessary feathers • Pluck in opposite direction • Chlorexidine or Betadine scrub • Saline • Alcohol will cause heat loss • Transparent sterile drape • Retains heat • Easier to monitor patient

16. Transparent Drape

17. Monitoring • Manual • Auscult heart rate • Stethoscope, esophageal stethoscope • Observe breathing • Can be difficult to visualize • Lungs rigid, no diaphragm • Muscular movement of ribs/sternum • Relaxed when anesthetized • Shivering = too light

18. Monitoring • ECG – Heart activity • Larger birds • Smaller birds • Machine that can register rapid heart rate • Doppler – Blood pressure • Medial metatarsal artery • Radial artery • Pulse Oximeter – Oxygen saturation • Femur, foot, toe, radius • Can be difficult to get a reading • Cloacal or esophageal thermometer

19. Monitoring Blood Pressure

20. Catheterization • Replace fluids lost • Maintain blood pressure • Blood Transfusion • IV Dextrose • Not often done • Difficult to monitor blood pressure • Avoid overhydration

21. Catheterization • Intravenous (IV) • Fragile veins: long-term is difficult • Jugular, basilic, medial metatarsal veins • Intraosseous (IO) • Bone • Distal ulna

22. Intraosseous Catheter

23. Anesthetized Patient a/b- et tube c- IVC d- IVF e- pulse ox

24. Thermal Support • High surface area to volume ratio = lose heat quickly • Heated surgery table • Water circulating blanket • Forced air blankets (Bair hugger) • NO Heat lamps/heating pads • NOT RECOMMENDED! • thermal burns even on low setting

25. Heat Support

26. IPPV • Intermittent Partial Pressure Ventilation • “Bagging” • Mechanical Ventilator • Inflates and circulates air through air sacs • 1-4 times per minute • Do not exceed 15mm H2O • Overinflation, rupture of air sacs

27. IPPV - Bagging

28. Recovery • Incubator • Stabilize temperature • Oxygen support • Wrapped in towel • Remove endotracheal tube • Chewing/swallowing, head shaking, flapping wings • Feed small amount of food or few drops 50% dextrose • hypoglycemia

29. Incubator

30. Instruments & Equipment • Small specialized surgical instruments • Ophthalmology instruments • Delicate and precise • Laser • Cauterizes for hemostasis • Shorter surgical/anesthesia times • Endoscope

31. Equipment • Optical Magnification • Binocular head sets • microscope

32. Suture • Fine suture for thin skin • 4-0 to 8-0 • Tapered needle • Tissue glue

33. Suture

34. Sources Cited • Ballard, B., & Cheek, R. (2003). Exotic Animal Medicine for the Veterinary Technician. Iowa: Blackwell Publishing. • Tully, Jr., T.N., & Mitchell, MA. (2001). A Technician’s Guide to Exotic Animal Care. Colorado: AAHA Press. • Nielsen, L. (1999). Chemical Immobilization of Wild and Exotic Animals. Iowa: Iowa State University Press. • Tseng, F.S., & Kaufman, G. Avian Anesthesia and Surgery. Retrieved March 15, 2008, from Tufts University Open Courseware. Web site: http://ocw.tufts.edu/Content /5/lecturenotes/215768 • Gunkel, C., & Lafortune, M. (2005). Current Techniques in Avian Anesthesia. Seminars in Avian and Exotic Pet Medicine, 14,4, 263-276. Retrieved March 15, 2008, from Science Direct Database. • Avian Surgery: To Cut is to Cure. (2006). Exotic Pet Veterinarian. Retrieved March 15, 2008, from http://www.exoticpetvet.net/avian/surgery.html • Exotic Animal Anesthesia, Perioperative Support, and Surgical Instrumentation. Michigan Veterinary Medical Association. Retrieved March 15, 2008, from http://www.michvma.org/