The Effects of Prophylactic Dexmedetomidine Administration on General Anesthesia Recovery Quality in Healthy Dogs Anesthetized With Sevoflurane and a Fentanyl Constant Rate Infusion Undergoing Elective Orthopedic Procedures.

To determine the effects of a dexmedetomidine slow bolus, administered prior to extubation, on recovery from sevoflurane-anesthesia and a fentanyl continuous rate infusion (CRI) in dogs undergoing orthopedic surgical procedures. Sixty-two client-owned, healthy dogs weighing 27.4 ± 11 kg undergoing elective orthopedic procedures were premedicated with: 0.1 mg/kg hydromorphone intramuscular, 0.05 mg/kg hydromorphone intravenously (IV) or 5 mcg/kg fentanyl IV. Following premedication, dogs were induced with propofol, administered locoregional anesthesia and maintained with sevoflurane and a fentanyl CRI (5-10 mcg/kg/hr). Dogs were randomly assigned to one of two treatment groups: 0.5 mcg/kg dexmedetomidine (DEX) or 0.5 ml/kg saline (SAL). Following surgery, patients were discontinued from the fentanyl CRI and administered DEX or SAL IV over 10 min. Following treatment, dogs were discontinued from sevoflurane and allowed to recover without interference. Recoveries were video recorded for 5 min following extubation and assessed by two blinded anesthesiologists using a visual analog scale (VAS; 0-10 cm) and a numerical rating scale (NRS; 1-10). Mean arterial pressure (MAP), heart rate (HR), pulse oximetry (SpO2), temperature, respiratory rate (RR), and end-tidal sevoflurane (EtSevo) and carbon dioxide (EtCO2) concentrations were recorded at specific time-points from induction to 5 min post-bolus administration and analyzed using linear mixed models. Fentanyl, propofol, and hydromorphone dose and the time to extubation were compared using an unpaired t-test. Differences in recovery scores between groups were evaluated with a Mann-Whitney test. Data reported as mean ± SD or median [interquartile range] when appropriate. A p < 0.05 was significant. There were no significant differences between groups in fentanyl, propofol, and hydromorphone dose, duration of anesthesia, intraoperative MAP, HR, RR, SpO2, temperature, EtCO2, EtSevo or anesthetic protocol. MAP was higher in DEX compared to SAL at 10 (104 ± 27 and 83 ± 23, respectively) and 15 (108 ± 28 and 86 ± 22, respectively) min after treatment. DEX had significantly lower VAS [0.88 (1.13)] and NRS [2.0 (1.5)] scores when compared to SAL [VAS = 1.56 (2.59); NRS = 2.5 (3.5)]. Time to extubation (min) was longer for DEX (19.7 ± 11) when compared to SAL (13.4 ± 10). Prophylactic dexmedetomidine improves recovery quality during the extubation period, but prolongs its duration, in sevoflurane-anesthetized healthy dogs administered fentanyl.

The effects of xylazine or detomidine when used as a pre-anesthetic sedative on recovery quality and duration in horses undergoing elective equine castration.

The purpose of this prospective, blinded, randomized clinical trial was to compare the effects of low dose detomidine to xylazine on recovery quality and duration in a castration procedure. Horses were administered either detomidine [0.015 mg/kg body weight (BW)] or xylazine (1.1 mg/kg BW) intravenously (IV) before IV induction with ketamine (2.2 mg/kg BW) and diazepam (0.05 mg/kg BW). Two anesthesiologists who were unaware of treatment allocation scored the recoveries using a simple descriptive scale (with a low number representing the most desirable recovery) and recoveries were timed. Horses in the detomidine group (n = 16) had a median recovery score of 16 (range: 11 to 26), whereas horses in the xylazine group (n = 12) had a median recovery score of 12 (range: 10 to 16) (P = 0.001). There was no difference in surgery time (P = 0.52), time from the end of surgery to standing (P = 0.45), or time from induction to standing (P = 0.48) between the groups.

Les effets de la xylazine ou de la détomidine lors d'utilisation comme sédatif pré-anesthésique sur la qualité et la durée de la récupération chez les chevaux soumis à une castration équine élective. Le but de cet essai clinique prospectif, en aveugle et randomisé était de comparer les effets de la détomidine à faible dose à la xylazine sur la qualité et la durée de la récupération dans une procédure de castration. Les chevaux ont reçu soit de la détomidine [0,015 mg/kg de poids corporel (PC)] soit de la xylazine (1,1 mg/kg de PC) par voie intraveineuse (IV) avant l'induction IV avec de la kétamine (2,2 mg/kg de PC) et du diazépam (0,05 mg/kg de PC). Deux anesthésistes qui ignoraient l'attribution du traitement ont noté les récupérations à l'aide d'une échelle descriptive simple (avec un petit nombre représentant la récupération la plus souhaitable) et les récupérations ont été chronométrées. Les chevaux du groupe détomidine (n = 16) avaient un score de récupération médian de 16 (éventail de valeurs : 11 à 26), tandis que les chevaux du groupe xylazine (n = 12) avaient un score de récupération médian de 12 (éventail de valeurs : 10 à 16) (P = 0,001). Il n'y avait aucune différence dans le temps de chirurgie (P = 0,52), le temps entre la fin de la chirurgie et la position debout (P = 0,45) ou le temps entre l'induction et la position debout (P = 0,48) entre les groupes.(Traduit par Dr Serge Messier).

Ultrasound-assisted injection of the centrodistal joint in the horse.

BACKGROUND: Injection of the centrodistal (CD) joint in the horse is a commonly performed procedure for both diagnostic and therapeutic purposes. This procedure can be technically challenging, and while radiographic guidance has been previously used, ultrasound localised injection of the CD joint has not been described. OBJECTIVES: The purpose of this study was to explore the feasibility of using ultrasound localisation to increase the accuracy of CD joint injection. STUDY DESIGN: Experimental method assessment. METHODS: One operator performed the ultrasound and injection of 24 CD joints in 12 sedated horses. The joints were injected with iohexol (2 ml), sterile saline (1.5 ml) and amikacin (0.5 ml). Dorsoplantar and dorsomedial plantarolateral radiographic projections were obtained immediately after injection to evaluate the presence of contrast material in the CD joint. RESULTS: The CD joint was successfully injected in 17/24 joints, representing a 70.8% accuracy. MAIN LIMITATIONS: The horses used in this study were from the University research herd, and not clinical cases. One investigator performed all the ultrasonography and CD joint injections. CONCLUSIONS: The use of ultrasound localisation could improve success of CD joint injection as well as improve the learning curve of less experienced practitioners learning this procedure.