Evaluation of dexmedetomidine and ketamine in combination with opioids as injectable anesthesia for castration in dogs.

OBJECTIVE: To compare efficacy and cardiorespiratory effects of dexmedetomidine and ketamine in combination with butorphanol, hydromorphone, or buprenorphine (with or without reversal by atipamezole) in dogs undergoing castration. DESIGN: Prospective, randomized, split-plot, blinded study. ANIMALS: 30 healthy client-owned sexually intact male dogs. PROCEDURES: Dogs (n = 10 dogs/group) were assigned to receive dexmedetomidine (15 µg/kg [6.82 µg/lb]) and ketamine (3 mg/kg [1.36 mg/lb]) with butorphanol (0.2 mg/kg [0.09 mg/lb]; DKBut), the same dosages of dexmedetomidine and ketamine with hydromorphone (0.05 mg/kg [0.023 mg/lb]; DKH), or the same dosages of dexmedetomidine and ketamine with buprenorphine (40 µg/kg [18.18 µg/lb]; DKBup). All drugs were administered as a single IM injection for induction and maintenance of anesthesia for castration. At conclusion of the surgery, 5 dogs in each treatment group received atipamezole (150 µg/kg [68.18 µg/lb], IM), and the remainder received saline (0.9% NaCl) solution IM. Cardiorespiratory variables and quality of anesthesia were assessed. Supplemental isoflurane was administered to the dogs when anesthesia was considered inadequate during surgery. RESULTS: All drug combinations rapidly induced anesthesia. Dogs were intubated within 10 minutes after injection. Supplemental isoflurane was needed during surgery in 1, 3, and 4 dogs in the DKBup, DKBut, and DKH groups, respectively. Dogs that received atipamezole had a significantly shorter recovery time. Some dogs in each group had bradycardia and hypoxemia with hypertension. CONCLUSIONS AND CLINICAL RELEVANCE: DKBup was the most suitable injectable anesthetic combination used. Recovery was shortened by IM administration of atipamezole. There were minimal adverse effects in all groups.

Evaluation of dexmedetomidine and ketamine in combination with various opioids as injectable anesthetic combinations for castration in cats.

OBJECTIVE: To compare the efficacy and cardiorespiratory effects of dexmedetomidine-ketamine in combination with butorphanol, hydromorphone, or buprenorphine with or without reversal by atipamezole in cats undergoing castration. DESIGN: Prospective, randomized, split-plot, blinded study. ANIMALS: 30 healthy male cats. PROCEDURES: Cats were assigned to receive dexmedetomidine (25 ?g/kg [11.4 ?g/lb]) and ketamine (3 mg/kg [1.4 mg/lb]) with butorphanol (0.2 mg/kg [0.09 mg/lb]; DKBut; n = 10), hydromorphone (0.05 mg/kg [0.023 mg/lb]; DKH; 10), or buprenorphine (30 ?g/kg [13.6 ?g/lb]; DKBup; 10). Drugs were administered as a single IM injection. Supplemental isoflurane was administered to cats if the level of anesthesia was inadequate for surgery. At the conclusion of surgery, half the cats (5 cats in each treatment group) received atipamezole (250 ?g/kg [113.6 ?g/lb], IM) and the remainder received saline (0.9% NaCl) solution IM. All cats received meloxicam (0.2 mg/kg, SC) immediately prior to the conclusion of surgery. RESULTS: All drug combinations induced lateral recumbency, and intubation was achievable in 13 of 30 (43%) cats at 10 minutes after injection. Supplemental isoflurane was needed for the surgery in 1 of 10 of the DKBut-, 2 of 10 of the DKH-, and 7 of 10 of the DKBup-treated cats. Cats that received atipamezole had a significantly shorter recovery time. CONCLUSIONS AND CLINICAL RELEVANCE: DKBut and DKH combinations were suitable injectable anesthetic protocols for castration in cats commencing at 10 minutes after injection, but cats receiving DKBup may require additional time or anesthetics for adequate anesthesia.

Buried tension sutures: force-tension comparisons of pulley, double butterfly, mattress, and simple interrupted suture patterns.

OBJECTIVES: To compare suture patterns (simple interrupted, modified pulley, horizontal mattress, double butterfly) by use of a novel in vitro model that quantifies force required for closure against tension. STUDY DESIGN: In vitro study. SAMPLE POPULATION: Suture constructs. METHODS: An in vitro suturing frame was constructed with extension springs to provide a standard resistance against movement of 2 panels of loops toward each other. Four different suture patterns were applied to the frame in randomized trials. The frame was affixed to a tensiometer that measured the force required for each suture pattern to close a fixed distance (3.81 cm) at a constant rate (5.08 cm/min) against the tension (0.6 kg/cm) of the extension springs. The closure distance and tension were selected subjectively to mimic tension encountered clinically during wound reconstruction oncologic surgical procedures. RESULTS: The modified pulley suture required the least force to close, followed by the double butterfly, simple interrupted, and horizontal mattress patterns. CONCLUSIONS: The modified pulley suture and double butterfly suture patterns require less force to close a given distance under tension than either simple interrupted or horizontal mattress suture patterns. CLINICAL RELEVANCE: Application of tension relieving suture techniques for fascia, subcutaneous, and buried-knot subdermal suturing should be considered to facilitate direct closure of wounds under tension. Modified pulley and double butterfly suture patterns offer some mechanical advantage by requiring less force to achieve closure compared with other suture patterns that might be used in reconstructive surgery.