Recovery from anesthesia - This time is critical because it is a period of physiologic disturbance during which crises can arise. Frequent observation and monitoring is required. The endotracheal tube should not be removed until the animal is exhibiting an active swallowing reflex. Maintain a clear, unobstructed airway! For dogs, the neck is extended and the tongue gently pulled out of one side of the mouth. Rodents should not be placed in cages with bedding, which can be inhaled. In most instances, animals should be frequently turned from side to side to avoid dependent pulmonary edema. Respiratory function can be evaluated by mucous membrane and tongue color and respiratory volume and rate. Some situations may require a blood gas analyzer. Cardiovascular function can be assessed by EKG, blood pressure monitors, auscultation, and evaluation of mucous membrane color. Body temperature needs to be maintained. If circulating warm water heating devices or heat lamps are used, care should be taken to ensure that animals do not chew these devices and electrocute themselves. To prevent drowning or aspiration, water and food is withheld.

 

In general, animals should be individually caged during this time period. It is not uncommon in species including rats, pigs and dogs, for those individuals which first regain consciousness to cannibalize those which are still groggy. Rodents should not be returned to group cages until each and every individual in the cage has regained normal mobility. If frequently observed, large farm animals can recover in their own stall rather than in a special recovery area. Regurgitation associated with the movement of the rumen may be avoided by not moving the animal more than necessary.

 

Acute postoperative care - includes the time the animal is maintained in the recovery area until it is ready to be moved to standard housing. Analgesics, antibiotics and additional fluids might be needed during this time period. Animals need to be monitored frequently if fluid catheters or electrical heating devices are used, to prevent the animal chewing on exposed devices. Once the animal is fully awake, food and water may be started. All animals, including rodents, should be returned to clean cages with fresh bedding to prevent fecal contamination of the fresh surgical incision. If there is danger of injury from other animals, animals should be individually housed.

Long term postoperative care - requires careful observation of body temperature, food intake, locomotion, behavior, and signs indicating pain. For warm-blooded species "higher" than rodents, notes must be maintained in an individual animal record and each entry should be dated and initialed.

 

Research staff must daily examine the surgical site, monitor for signs of infection, and remove sutures or other devices at the correct time (generally 7-10 days). The surgical site should be observed for signs of infection, incision breakdown (dehiscence), or self-inflicted trauma. At least once a day, catheters should be examined and may need to be cleaned and flushed. Drains, collars, and dressings should be examined daily and changed as needed. Bandages, Elizabethan collars and restraint devices may help prevent self-mutilation; but staff must watch that the animal can obtain food and water and move about to perform bodily functions.

 

Monitoring food and water intake is important to successful recovery. Oral or parenteral supplementation may be necessary to maintain normal hydration and anabolic state. Special diets may be indicated during the recovery period. The quantity and character of urine and feces should be monitored, because changes could indi-cate complications such as paralytic ileus, acute renal failure, or intestinal hypermotility caused by irritation. Disposition of animals - Euthanasia of animals must be performed when required by the protocol, or at the end of a procedure which would leave the animals with pain not relieved by drugs. Euthanasia methods must conform to the most recent Report of the AVMA Panel on Euthanasia. All animal remains should be returned to the designated freezer(s) in Institutional Animal Care facilities. Animals exposed to biohazardous materials involve special precautions as described by Environmental Services. Never put animal remains in laboratory trash cans or outside dumpsters.

 

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