Effects of acepromazine and trazodone on anesthetic induction dose of propofol and cardiovascular variables in dogs undergoing general anesthesia for orthopedic surgery

Abstract

OBJECTIVE To compare the doses of propofol required to induce general anesthesia in dogs premedicated with acepromazine maleate or trazodone hydrochloride and compare the effects of these premedicants on cardiovascular variables in dogs anesthetized for orthopedic surgery. DESIGN Prospective, randomized study. ANIMALS 30 systemically healthy client-owned dogs. PROCEDURES 15 dogs received acepromazine (0.01 to 0.03 mg/kg [0.005 to 0.014 mg/lb], IM) 30 minutes before anesthetic induction and 15 received trazodone (5 mg/kg [2.27 mg/lb] for patients > 10 kg or 7 mg/kg [3.18 mg/lb] for patients ≤ 10 kg, PO) 2 hours before induction. Both groups received morphine sulfate (1 mg/kg [0.45 mg/lb], IM) 30 minutes before induction. Anesthesia was induced with propofol (4 to 6 mg/kg [1.82 to 2.73 mg/lb], IV, to effect) and maintained with isoflurane or sevoflurane in oxygen. Bupivacaine (0.5 mg/kg [0.227 mg/lb]) and morphine (0.1 mg/kg [0.045 mg/lb]) were administered epidurally. Dogs underwent tibial plateau leveling osteotomy (n = 22) or tibial tuberosity advancement (8) and were monitored throughout anesthesia. Propofol induction doses and cardiovascular variables (heart rate and systemic, mean, and diastolic arterial blood pressures) were compared between groups. RESULTS The mean dose of propofol required for anesthetic induction and all cardiovascular variables evaluated did not differ between groups. Intraoperative hypotension developed in 6 and 5 dogs of the acepromazine and trazodone groups, respectively; bradycardia requiring intervention developed in 3 dogs/group. One dog that received trazodone had priapism 24 hours later and was treated successfully. No other adverse effects were reported. CONCLUSIONS AND CLINICAL RELEVANCE At the described dosages, cardiovascular effects of trazodone were similar to those of acepromazine in healthy dogs undergoing anesthesia for orthopedic surgery.

Effect of different anesthetic mixtures—ketamine‐xylazine, ketamine‐acepromazine and tiletamine‐zolazepam—on the physiological and blood biochemistry parameters of male rhesus monkeys (Macaca mulatta) at different ages

“…Increases in CK have also been associated with a decrease in body temperature . This relates to descriptions in various articles which mention that the anesthetic combinations of ketamine‐xylazine and tiletamine‐zolazepam lower body temperature, and while the values we obtained are similar to those reported for CK and LDH, these statistical differences could be related to the anesthetic mixtures utilized . Finally, our study observed changes in electrolytes, including a decrease in Ca in the cases of KA and KX.…”

“…This, in turn, produces sedation and muscular relaxation while also reducing motor activity. However, the secondary effects described include hypotension, bradycardia, and a slight depression of the respiratory system . These changes were observed in experimental Group A in our study.…”

Trazodone: A Review of Its Pharmacological Properties and Its Off-Label Use in Dogs and Cats

“…However, tachycardia was reported in experimental dogs immediately after IV administration at high trazodone blood concentrations (Jay et al, 2013) and in anesthetized dogs when compared with imipramine at the same dose after IV administration Je and Aw, 1982). Intraoperative hypertension and bradycardia developed in healthy dogs undergoing anesthesia for orthopedic surgery when compared with acepromazine (Murphy et al, 2017). Other adverse events such as priapism (seldom reported in humans) was found in 1 out of 15 dogs that received trazodone 24 h after undergoing anesthesia for orthopedic surgery (Murphy et al, 2017).…”

“…Intraoperative hypertension and bradycardia developed in healthy dogs undergoing anesthesia for orthopedic surgery when compared with acepromazine (Murphy et al, 2017). Other adverse events such as priapism (seldom reported in humans) was found in 1 out of 15 dogs that received trazodone 24 h after undergoing anesthesia for orthopedic surgery (Murphy et al, 2017). Trazodone is reported to have potential risk for the serotonin syndrome when used with other Selective Serotonin Reuptake Inhibitor (SSRI) and/or Tricyclic Antidepressant (TCA) agents.…”

“…The pre-operative use of trazodone has been less well documented in literature, however it is commonly used, off-label, for this practice (Gilbert-Gregory et al, 2016;Murphy et al, 2017). Veterinary hospitals are using trazodone to pre-medicate dogs in combination with opioid agents (Murphy et al, 2017) but no information is reported in cats yet.…”