Cardiorespiratory Effects of Four Opioid‐Tranquilizer Combinations in Dogs

Abstract

The cardiorespiratory effects of four opioid-tranquilizer combinations were evaluated in six dogs. The four combinations were administered to each dog in a randomized order. Buprenorphine (BUP; 0.01 mg/kg IV) or oxymorphone (OXY; 0.1 mg/kg IV) was followed in 10.4 +/- 1.3 minutes by midazolam (MID; 0.3 mg/kg IV) or acepromazine (ACE; 0.05 mg/kg IV). Nalbuphine (0.16 mg/kg IV) was administered 94.1 +/- 2.3 minutes after the tranquilizer was given. Heart rate (HR) and mean arterial blood pressure (MAP) decreased significantly (P < .05) after each combination. MAP was significantly lower with combinations using ACE. Most dogs panted after opioid administration; this was associated with increased minute volume (VM) and decreased tidal volume (VT). After administration of the tranquilizer, mean breathing rate and VM index (VMI) were significantly lower with ACE combinations. There were no significant changes in pH and blood gas variables after BUP-ACE. The other three combinations were associated with significant (P < .05) decreases in pH and increases in PaCO2. Mean PaO2 decreased significantly (P < .05) with OXY combinations but not BUP combinations. Dysrhythmias (atrial or ventricular escape complexes) were seen with each combination. HR increased significantly (P < .05) after nalbuphine in dogs receiving OXY, but not BUP. Dogs receiving OXY became more alert after nalbuphine on six of 12 occasions, whereas dogs receiving BUP became less alert on six of 12 occasions. OXY-ACE provided the most chemical restraint/sedation and BUP-MID provided the least.

Evaluation of postoperative respiratory function by serial blood gas analysis in dogs treated with transdermal fentanyl

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Postoperative hypoxemia and hypercarbia in healthy dogs undergoing routine ovariohysterectomy or castration and receiving butorphanol or hydromorphone for analgesia

“…[6][7][8] Similar to hypoxemia, hypercarbia is difficult to detect on the basis of physical signs alone. Frequently, pure opioid agonists are used perioperatively for analgesia in dogs, and most pure opioid agonists cause respiratory depression and hypercarbia.…”

Respiratory Reflexes in Response to Upper‐Airway Administration of Sevoflurane and Isoflurane in Anesthetized, Spontaneously Breathing Dogs

“…It is unclear whether changing plasma concentrations of buprenorphine and/or acepromazine after bolus administration might affect the breathing pattern of animals. However, we assume that the use of buprenorphine (0.01 mg/kg) and acepromazine (0.05 mg/kg) did not have a major effect on the results of the present study, because respiratory variables stayed within reference limits following their administration at these doses to dogs 16,23 …”