Recovery And Analgesia

By | 2011-07-21

Recovery involves ventilation with 100% oxygen. The endotracheal tube is removed once the bird will no longer tolerate its presence. Regardless of the anesthetic used, practically all patients will appear disorientated and will attempt to flap their wings during recovery. Every attempt should be made to gently constrain them (without restricting respiration) to ensure that they do not damage their wings / feathers. This can be best achieved by lightly wrapping them in a towel. Usually with isoflurane anesthesia, recovery is over in 5-10 minutes, however if ketamine is used recovery may take much longer. During any recovery period the environmental temperature should be kept in the 25-30 °C range to prevent hypothermia developing. Keeping the recovery area quiet and dimly lit to ensure minimal adverse stimulation is advised.

The patient should be encouraged to take food as soon as it is able, again to minimise the deleterious effects of hypoglycaemia seen in these high metabolic rate species.

Analgesia

Analgesia has been shown to reduce the time taken for an avian patient to return to normal eating and preening behaviour, to reduce levels of anesthetic required if administered preoperatively, and to result in less wound breakdowns due to self-trauma (Table Commonly used analgesics in birds).

Table Commonly used analgesics in birds

Analgesic drug Dose rate Dosing interval
Butorphanol 1-4mg / kg subcutaneously, intramuscularly

0.02-0.04 mg / kg intravenously

q6-8h
Buprenorphine 0.02-0.06 mg / kg subcutaneously, intramuscularly q8-12h
Meloxicam 0.1-0.2 mg / kg subcutaneously, intramuscularly, peros q24h
Carprofen 2-4 mg / kg subcutaneously, peros q24h

(SC = subcutaneously; IM = intramuscularly; IV = intravenously; PO = peros; q6h = every 6 hours; q8h = every 8 hours; q12h = every 12 hours; q24h = every 24 hours)

Opioids such as butorphanol at 3-4mg / kg have been used in cockatoos and African grey parrots. Doses may need to be repeated three times daily due to its relatively short-acting properties. It does however have some respiratory suppression side effects and requires liver metabolism to be excreted. Other opioids used include buprenorphine at doses of 0.1 mg / kg intravenously or intramuscularly twice daily. Buprenorphine is a predominant μ opioid receptor partial agonist and studies in pigeons at least have suggested that birds’ central nervous system receptors are mainly K rather than p.. Butorphanol therefore may be the preferred opioid in many birds.

Non-steroidal anti-inflammatory drugs (NSAIDs), such as carprofen at 4-5 mg / kg once daily, have been used. Others include meloxicam at 0.2-0.3 mg / kg once daily. As these are all NSAIDs particular care should be taken in patients with gastrointestinal or renal disease; avian patients, due to their kidney structure, are more sensitive to some of these side effects than their mammalian counterparts. This is particularly so in some birds of prey such as the Indian white-necked vulture (Gyps bengalensis) which has been nearly wiped out by the NSAID diclofenic acid used in cattle, the fallen carcases of which formed a large part of its diet. The cause of death has been well reported as kidney damage. This author has found meloxicam to be generally safe in many species including many birds of prey such as vultures, however care should still be used in novel species. Concurrent fluid therapy is often advised when using NSAIDs, with or without gastrointestinal protectants such as sucralfate and cimetidine.