Avian patients will at times require anesthesia for radiographs, fracture repairs, bandage changes, mass removals, etc. Once it has been determined that anesthesia is going to be required a thorough physical examination needs to be performed, being sure to listen to the heart and all air sacs and weigh the patient.
Pre-anesthetic blood work is always helpful, particularly in our older and ill patients. Drawing blood on avian patients is not as difficult as some think. See our Specialty Folder for an article on Avian Venipuncture. The minimum diagnostic test for anesthesia should include a chemistry and CBC.
Avian patients have a high metabolic rate and due to this, extended fasting can be detrimental to these patients. The purpose of fasting is to ensure emptying of the crop which will prevent passive reflux of fluid or food material during anesthesia. Material refluxed may cause an obstruction in the airway and/or cause pneumonia. The recommendation is to fast avian patients between 1-3 hours; keep in mind the smaller the bird the shorter the fast. Also water only has to be withheld one hour; this is long enough to prevent regurgitation, but short enough to prevent dehydration.
Pre-anesthetic medications are infrequently used in avian patients. Atropine and glycopyrrolate have been used to reduce vagally induced bradycardia and to reduce oral secretions. They both have unwanted side effects including causing unacceptably high heart rates, increasing myocardial oxygen demand and increasing the risk of cardiac hypoxia and arrest. At times these medications will make the oral or respiratory secretions so thick they make endotracheal tube blockage very likely.
Fluid therapy is very important in all anesthetic avian patients. Fluids can be delivered pre-, intra- and post-operative. Whether it is a crystalloid or colloid, fluid therapy can be the difference between a successful surgery and a failure.
Reference:
Veterinary Nursing of Exotic Pets – Girling
Exotic Animal Care – Tully and Mitchell
Exotic Animal Medicine for the Veterinary Technician – Ballard and Cheek
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