ClinQuiz: Implementing the American Animal Hospital Association's Anesthesia Guidelines (Sponsored by Abbott Animal Health) Answer 4B
4 B. — Correct!
Delayed recovery from anesthesia is often due to a number of factors. Residual CNS depression is common in older patients. Drug clearance is often reduced in aged patients because of limited metabolic elimination and altered pharmacokinetics. Geriatric patients typically require reduced doses of anesthetics, and, without individualized attention, relative overdoses can occur in this population. If a relative overdose of anesthetics is identified, individualized physiological support and postoperative care would be indicated to achieve the goals for recovery.
Physiologic support is primary in any patient with delayed recovery from anesthesia. Further patient evaluation can lead to appropriate interventions. The dog's anesthetic depth, oxygenation, ventilation, temperature, and cardiovascular function should be monitored throughout the entire anesthetic period, including recovery. In this case, thermal support had been discontinued at the termination of anesthesia and the dog's body temperature had decreased during recovery. Hypothermia is one of the most frequently encountered causes of delayed recovery from anesthesia and commonly contributes to postanesthetic morbidity and mortality. In addition, although opioid administration was appropriate in this patient, opioids tend to disrupt thermoregulation, suppress thermogenesis, and allow continued cooling.
Gradual external warming must be initiated and managed to prevent burns. Shivering should be avoided, because it increases oxygen demand three- to six-fold and postoperative stress. Once body temperature returns to near normal, the significance of residual opioid-mediated sedation can be reconsidered. Continued nursing care and physiological support are required and will contribute to improved outcome.