Hypothermia in birds under general anesthesia is frequently seen, causing physiologic and metabolic alterations that may lead to death. This study evaluated two thermic maintenance methods in chickens under inhalant anesthesia by isoflurane. Six chickens, weighing between 1 and 1.5kg and with approximately one year old, were submitted to three groups in a random order: CG, control, nothing was used; GA, wrapped in a commercial aluminum paper, and GM, wrapped in a double face blanket of aluminum. After four hour fasting, they were submitted to inhalant anesthesia by facial mask with 4V% of isoflurane, and maintained with 2V% of this gas through a humidifier nonrebreathing circuit after endotracheal intubation. In GM and GA the animals body were wrapped in their totality, exception of the head. Body temperature, heart rate, respiratory rate and oxyhemoglobin saturation were measured at 0, 15, 30, 45, 60, 75 and 90 minutes. In GC and GM hypothermia occur with 15 minutes, staying in constant fall until 90 minutes. The difference in GA with basal level occurs only between 45 to 90 minutes. Bradycardia occurred in control group at 15 minutes, in blanket group at 30 minutes and in aluminum group only at 60 minutes. Bradypnea was observed in GC at 45 minutes, and at 15 and 30 minutes in GA and GM, respectively. No significant alterations were seen for to oxihemoglobin saturation. Both methods employed were effective on thermic maintenance, showing the aluminum more effective due less variation observed in body temperature and heart rate.
thermoregulation; anesthesia; chicken; Gallus gallus domesticus; isoflurane
