AVIAN ANESTHESIA &

SURGERY

Kim HealyVETS 247 – Exotic Animal Medicine and NursingDr. MeckelSpring 2008

Anesthetic Procedures Surgical sexing

– Not as commonly done now

– DNA testing Abscess/Wound

repair Repair bone

fractures Foreign body

removal Growth removals

Anesthetic Procedures

Radiography Endoscopy Repair beak

abnormalities– Scissor beak

Reproductive problems– Egg-bound

Many more

Preanesthetic Period

Complete History Physical Exam Diagnostics

– CBC/Chem– +/- Radiographs or Ultrasound

Stabilization for critical patients Fasting: 0-2 hours prior to

procedure

Premedication Rarely used

– Stress from handling– Unpredictability of injectable drugs

Anticholinergics (Atropine,

Glycopyrrolate)– If history of bradycradia

Opioids (Butorphanol)– Reversible

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

Induction Injectables

– Unpredictable effects– Side effects– Extended recovery times

Ketamine +/- Benzodiazepines– Long & stormy recovery

Propofol– Respiratory depression– Stormy recovery

Induction

Mask

Commercially made Home made

– Plastic bottles or syringe cases

Smaller patients– Whole head inside

mask

Intubation

Can use mask for very short procedures

Intubation provides:– Manual ventilation– Prevents aspiration

Non-rebreathing system– Less than 7kg

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

Intubation

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

Air Sac Cannulation

Local Anesthesia

Example – Lidocaine Not recommended

– Necessary dose higher than toxic dose, especially in smaller birds

– Restraint of an awake bird is difficult

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

Transparent Drape

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

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

Monitoring Blood Pressure

Catheterization

Replace fluids lost Maintain blood pressure Blood Transfusion IV Dextrose

Not often done– Difficult to monitor blood pressure– Avoid overhydration

Catheterization

Intravenous (IV)– Fragile veins: long-term is difficult– Jugular, basilic, medial metatarsal veins

Intraosseous (IO)– Bone– Distal ulna

Intraosseous Catheter

Anesthetized Patient

a/b- et tube c- IVC d- IVF e- pulse ox

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

Heat Support

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

IPPV - Bagging

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

Incubator

Instruments & Equipment

Small specialized surgical instruments

Ophthalmology instruments– Delicate and precise

Laser– Cauterizes for

hemostasis– Shorter

surgical/anesthesia times

Endoscope

Equipment

Optical Magnification– Binocular head sets– microscope

Suture

Fine suture for thin skin

4-0 to 8-0 Tapered needle Tissue glue

Suture

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/