Topic:Butorphanol
Butorphanol is an opioid analgesic commonly used in equine medicine for its pain-relieving and sedative properties. It acts on the central nervous system by binding to opioid receptors, providing relief from moderate to severe pain. Butorphanol is often utilized in horses for managing pain associated with colic, surgical procedures, and other medical conditions. Its effects include sedation and analgesia, with a relatively short duration of action compared to other opioids. This page compiles peer-reviewed research studies and scholarly articles that explore the pharmacokinetics, efficacy, safety, and clinical applications of butorphanol in equine practice.
Pharmacokinetics and pharmacodynamics of l-methadone in isoflurane-anaesthetized and mechanically ventilated ponies. To evaluate the pharmacokinetics and selected pharmacodynamic effects of a commercially available l-methadone/fenpipramide combination administered to isoflurane anaesthetized ponies. Methods: Prospective single-group interventional study. Methods: A group of six healthy adult research ponies (four mares, two geldings). Methods: Ponies were sedated with intravenous (IV) detomidine (0.02 mg kg) and butorphanol (0.01 mg kg) for an unrelated study. Additional IV detomidine (0.004 mg kg) was administered 85 minutes later, followed by induction of anaesthesia using IV diazepam (0.05 mg kg) and keta...
Effect of multiple head positions on intraocular pressure in healthy, anesthetized horses during hoisting. To evaluate changes in intraocular pressure (IOP) with variable head position in healthy, anesthetized horses in hoisted inversion and to assess the influence of various cofactors (age, sex, body weight, body condition score, and neck length) on IOP changes during hoisting. Methods: Seventeen healthy adult horses without significant ocular abnormalities. Methods: Subjects were administered intravenous xylazine/butorphanol premedication and ketamine/midazolam induction with xylazine/ketamine boluses for anesthetic maintenance. While hoisted, IOP was measured in triplicate for each eye via rebou...
Plasma histamine concentrations in horses administered sodium penicillin, guaifenesin-xylazine-ketamine and isoflurane with morphine or butorphanol. Various drugs administered to horses undergoing surgical procedures can release histamine. Histamine concentrations were evaluated in horses prepared for surgery and administered butorphanol or morphine intraoperative infusions. Methods: Prospective studies with one randomized. Methods: A total of 44 client-owned horses. Methods: In one study, anesthesia was induced with xylazine followed by ketamine-diazepam. Anesthesia was maintained with guaifenesin-xylazine-ketamine (GXK) during surgical preparation. For surgery, isoflurane was administered with intravenous (IV) morphine (group M: 0.15 mg ...
Arterial oxygenation in anesthetized horses placed in a 5-degree reverse Trendelenburg position. Low arterial oxygen is a common complication in anesthetized horses and placing the animal in reverse Trendelenburg (RT) position may treat hypoxemia. The objective of this study was to assess the arterial partial pressure of oxygen (PaO) in horses placed in a 5-degree RT compared to horizontal (H) position. Client-owned healthy horses (n = 60) undergoing elective surgeries were enrolled in a randomized controlled clinical study. Horses were sedated with butorphanol, an α-adrenoceptor agonist, ± acepromazine and induced with ketamine combined with a benzodiazepine, propofol, or guaifenesin...
Intraocular pressure following four different intravenous sedation protocols in normal horses. Intravenous sedation is frequently necessary for ophthalmic examination in horses. Common sedation protocols have not been directly compared in terms of relative intraocular pressure (IOP) reduction, duration of IOP reduction and time to maximum IOP reduction. Objective: To compare the effects of standing sedation protocols on IOP. Methods: Randomised cross-over experiment. Methods: Twelve healthy horses received four intravenous sedation protocols with a 48 hours washout: 0.5 mg/kg xylazine and 0.01 mg/kg butorphanol (SED1); 10 µg/kg detomidine and 0.01 mg/kg of butorphanol (SED2); 10 ...
Plasma prolactin, thyroid-stimulating hormone, melanocyte-stimulating hormone, and adrenocorticotropin responses to thyrotropin-releasing hormone in mares treated with detomidine and butorphanol. Stress or excitement is a concern when performing endocrine tests on fractious horses. Sedation may be a solution; however, perturbation of test results may preclude useful information. Thyrotropin-releasing hormone (TRH) is a known stimulator of prolactin, thyroid-stimulating hormone (TSH), melanocyte-stimulating hormone (MSH), and ACTH. Thyrotropin-releasing hormone-induced ACTH is a diagnostic tool for the assessment of endocrinopathies such as pituitary pars intermedia dysfunction. It is unknown if drugs commonly used for sedation alter endocrine responses. The objective of this study was ...
Clinical effects of two doses of butorphanol with detomidine for intravenous premedication of healthy warmblood horses. To compare the effects of two different doses of butorphanol combined with detomidine administered intravenously (IV) on quality of sedation, degree of ataxia and anaesthetic induction in horses. Methods: Randomized, blinded, clinical study. Methods: A total of 40 client-owned healthy warmblood horses scheduled for elective surgery under general anaesthesia. Methods: Horses were randomly allocated to be administered 8 μg kg-1 detomidine IV plus either 20 or 50 μg kg-1 butorphanol IV, with the principal investigator blinded to group allocation. Head height was measured before drug injection a...
A high-throughput and broad-spectrum screening method for analysing over 120 drugs in horse urine using liquid chromatography-high-resolution mass spectrometry. A high-throughput method has been developed for the doping control analysis of 124 drug targets, processing up to 154 horse urine samples in as short as 4.5 h, from the time the samples arrive at the laboratory to the reporting deadline of 30 min before the first race, including sample receipt and registration, preparation and instrument analysis and data vetting time. Sample preparation involves a brief enzyme hydrolysis step (30 min) to detect both free and glucuronide-conjugated drug targets. This is followed by extraction using solid-supported liquid extraction (SLE) and analysis using liq...
Evaluation of Stress Response under a Standard Euthanasia Protocol in Horses Using Analysis of Heart Rate Variability. The effects of a standard protocol for euthanasia on heart rate variability (HRV) as a consequence of stress response were analyzed in this prospective clinical study. The HRV was determined in 40 horses undergoing euthanasia due to various reasons, at different locations, and with/without owner presence. For euthanasia, horses were sedated with xylazine or a combination of xylazine and butorphanol. General anesthesia was induced using diazepam and ketamine. Afterwards, horses were euthanized with pentobarbital. The ECG data were taken by a Telemetric ECG at three time points (sedation, anesth...
The intravenous pharmacokinetics of butorphanol and detomidine dosed in combination compared with individual dose administrations to exercised horses. In equine and racing practice, detomidine and butorphanol are commonly used in combination for their sedative properties. The aim of the study was to produce detection times to better inform European veterinary surgeons, so that both drugs can be used appropriately under regulatory rules. Three independent groups of 7, 8 and 6 horses, respectively, were given either a single intravenous administration of butorphanol (100 µg/kg), a single intravenous administration of detomidine (10 µg/kg) or a combination of both at 25 (butorphanol) and 10 (detomidine) µg/kg. Plasma and urine concentratio...
Effects of Epinephrine, Detomidine, and Butorphanol on Assessments of Insulin Sensitivity in Mares. Sympathoadrenal stimulation may perturb results of endocrine tests performed on fractious horses. Sedation may be beneficial; however, perturbation of results may preclude useful information. Four experiments were designed to 1) determine the effects of epinephrine on insulin response to glucose (IR2G), 2) assess the effects of detomidine (DET), alone or combined with butorphanol (DET/BUT), on IR2G and glucose response to insulin (GR2I), and 3) assess the effects of BUT alone on IR2G. In Experiment 1, mares were administered saline or epinephrine (5 μg/kg BW) immediately before infusion of gl...
BEVA primary care clinical guidelines: Analgesia. Primary care guidelines provide a reference point to guide clinicians based on a systematic review of the literature, contextualised by expert clinical opinion. These guidelines develop a modification of the GRADE framework for assessment of research evidence (vetGRADE) and applied this to a range of clinical scenarios regarding use of analgesic agents. Key guidelines produced by the panel included recommendations that horses undergoing routine castration should receive intratesticular local anaesthesia irrespective of methods adopted and that horses should receive NSAIDs prior to surgery (ove...
Synovial butorphanol concentrations and mechanical nociceptive thresholds after intravenous regional limb perfusion in standing sedated horses. To determine synovial butorphanol concentrations and mechanical nociceptive threshold (MNT) changes after butorphanol intravenous regional limb perfusion (IVRLP). Methods: Experimental ANIMALS: Six adult horses. Methods: Cephalic IVRLP was performed with 10 mg butorphanol in sedated horses with a wide rubber tourniquet and a total volume of 30 mL. Radiocarpal synovial fluid and serum concentrations along with MNT were evaluated prior to and 0.5, 1, 2, 4, and 6 hours after IVRLP. Butorphanol concentrations were determined with liquid chromatography coupled to tandem mass spectrometry posi...
Behavioural and cardiovascular effects of medetomidine constant rate infusion compared with detomidine for standing sedation in horses. To compare the efficacy of a medetomidine constant rate infusion (CRI) with a detomidine CRI for standing sedation in horses undergoing high dose rate brachytherapy. Methods: Randomized, controlled, crossover, blinded clinical trial. Methods: A total of 50 horses with owner consent, excluding stallions. Methods: Each horse was sedated with intravenous acepromazine (0.02 mg kg-1), followed by an α2-adrenoceptor agonist 30 minutes later and then by butorphanol (0.1 mg kg-1) 5 minutes later. A CRI of the same α2-adrenoceptor agonist was started 10 minutes after butorphanol administration and ma...
Evaluation of the effects of commonly used α2-adrenergic receptor agonists alone and in combination with butorphanol tartrate on objective measurements of lameness in horses. To determine the effects of 3 α2-adrenergic receptor agonists (α2-ARAs), alone or in combination with butorphanol tartrate, on objective measurements of lameness in horses. Methods: 17 adult polo horses with naturally occurring forelimb or hind limb lameness (or both). Methods: In a crossover design, each horse received each protocol (saline [0.09% NaCl] solution [2 mL, IV] or xylazine hydrochloride [0.33 mg/kg, IV], detomidine hydrochloride [0.007 mg/kg, IV], or romifidine hydrochloride [0.033 mg/kg, IV] alone or in combination with butorphanol [0.007 mg/kg, IV]) in random order, with a was...
Accelerated Idioventricular Rhythm Associated With Isoflurane Administration in a Foal: A Case Report. A 2-day-old filly was referred to the hospital with abdominal pain and constipation. The foal presented tachycardia, tachypnea, hypoxemia, hyperlactatemia, and abdominal distension. Meconium impaction was diagnosed, and the filly underwent abdominal surgery. Diazepam and butorphanol were administered for anesthesia premedication, but sedative effects were mild. Xylazine was used to enhance sedation and ketamine was subsequently administered for induction. The foal showed swallow reflex and head movement when intubation was attempted. Consequently, isoflurane on oxygen was provided via an anest...
A kinematic comparison of the locomotor pattern of horses sedated with detomidine alone and in combination with low doses of butorphanol. Chemical restraint is often used to perform diagnostic and minor surgical procedures; α2 -adrenoceptor agonists are the most commonly used drugs; however, the combination with an opiate can induce a profound sedation. There is a lack of kinematic studies examining the effects of the combination of these drugs on locomotor patterns. Objective: The objective of the study was to evaluate the duration of the effects of sedation with detomidine and detomidine combined with a low dose of butorphanol on the movement patterns of horses. Methods: The study was a controlled, randomised, blinded and cro...
A comparison of two ketamine doses for field anaesthesia in horses undergoing castration. Ketamine at 2.2 mg/kg given i.v. is often used to induce anaesthesia for surgical procedures in horses under field conditions. Commonly, additional doses are needed to complete the surgery. We hypothesised that surgical conditions would be improved when 5 mg/kg of ketamine was used to induce anaesthesia, while induction and recovery qualities would not differ from those when 2.2 mg/kg ketamine was used. Objective: To compare the anaesthetic effects of two ketamine doses (5 and 2.2 mg/kg) during field anaesthesia for castration of horses. Methods: Prospective, randomised, blinded, clinical stud...
Influence of caudal epidural analgesia on cortisol concentrations and pain-related behavioral responses in mares during and after ovariectomy via colpotomy. To determine the influence of epidural detomidine and morphine on serum corticosteroid concentrations and pain-related behavioral responses in mares during and after ovariectomy via colpotomy. Methods: Blinded prospective study. Methods: Nine university-owned mares. Methods: Five of 9 horses received caudal epidural detomidine hydrochloride (0.01 mg/kg) and morphine sulfate (0.1 mg/kg) prior to surgery. All horses received local anesthetic around the ovarian pedicle, 0.02 mg/kg butorphanol IV at the start of the procedure and after first ovary removal, were sedated as required throughout the p...
Comparison of morphological changes and tactile sensitivity of the pharynx and larynx between four standing sedative and analgesic protocols in eight adult healthy horses. To compare the topographic modifications and tactile sensitivity of the pharynx and larynx after administration of four sedative and analgesic protocols in standing horses. Methods: Experimental, observer-blinded, crossover study. Methods: Eight healthy mares. Methods: Five protocols were evaluated: 1) xylazine and butorphanol administered intravenously (IV); 2) detomidine and butorphanol administered IV; 3) xylazine administered IV and lidocaine topically; 4) detomidine administered IV and lidocaine topically and 5) no analgesia or sedation (control). Quality of sedation, head height and sudd...
Effect of butorphanol, midazolam or ketamine on romifidine based sedation in horses during standing cheek tooth removal. Standing surgery, especially dental procedures, are commonly performed in horses. This leads to an increasing demand for reliable sedation protocols. Therefore, it was the purpose of this study to investigate the influence of butorphanol, midazolam or ketamine on romifidine based sedation in horses during cheek tooth removal. Methods: Forty horses presented for tooth extraction were divided in four groups using matched pair randomization. Group R was sedated with romifidine (bolus 0.03 mg/kg, followed by a constant rate infusion (CRI) 0.05 mg/kg/h) and group RB with romifidine (same dose) an...
In vivo evaluation of effects of sedation on results of acoustoelastography of the superficial digital flexor tendons in clinically normal horses. OBJECTIVE To assess the effects of sedation on results of acoustoelastography of the superficial digital flexor tendons (SDFTs) in clinically normal horses. ANIMALS 27 clinically normal horses. PROCEDURES For each horse, the pathology index (PI) for the SDFT of each thoracic limb was determined by use of acoustoelastography at 4 locations (5, 10, 15, and 20 cm distal to the accessory carpal bone). Horses were evaluated before and after they were sedated with a combination of detomidine hydrochloride (0.01 mg/kg, IV) and butorphanol tartrate (0.01 mg/kg, IV). A repeated-measures ANOVA was used ...
Evaluation of total intravenous anesthesia with propofol-guaifenesin-medetomidine and alfaxalone-guaifenesin-medetomidine in Thoroughbred horses undergoing castration. Anesthetic and cardiorespiratory effects of total intravenous anesthesia (TIVA) technique using propofol-guaifenesin-medetomidine (PGM) and alfaxalone-guaifenesin-medetomidine (AGM) were preliminarily evaluated in Thoroughbred horses undergoing castration. Twelve male Thoroughbred horses were assigned randomly into two groups. After premedication with intravenous (IV) administrations of medetomidine (5.0 µg/kg) and butorphanol (0.02 mg/kg), anesthesia was induced with guaifenesin (10 mg/kg IV), followed by either propofol (2.0 mg/kg IV) (group PGM: n=6) or alfaxalone (1.0 mg/kg IV) (group AGM...
Occurrence, treatment protocols, and outcomes of colic in horses within Nairobi County, Kenya. The aim of this study was to determine the treatments and their outcomes in horses with colic in Nairobi County, Kenya. Methods: This is a retrospective study to determine the occurrence, treatments, pain management, and outcomes of colic in horses in Nairobi County. Association between pain management protocols and the outcomes of colic with regard to recovery or death was also determined. Data collected from four equine practitioners were organized manually and given numerical codes as appropriate to facilitate entry into the computer. The coded data were entered into Microsoft Excel 2010 an...
Anesthetic management with sevoflurane combined with alfaxalone-medetomidine constant rate infusion in a Thoroughbred racehorse undergoing a long-time orthopedic surgery. A three-year old Thoroughbred racehorse was anesthetized with sevoflurane and oxygen inhalation anesthesia combined with constant rate infusion (CRI) of alfaxalone-medetomidine for internal fixation of a third metacarpal bone fracture. After premedication with intravenous (IV) injections of medetomidine (6.0 µg/kg IV), butorphanol (25 µg/kg IV), and midazolam (20 µg/kg IV), anesthesia was induced with 5% guaifenesin (500 ml/head IV) followed immediately by alfaxalone (1.0 mg/kg IV). Anesthesia was maintained with sevoflurane and CRIs of alfaxalone (1.0 mg/kg/hr) and medetomidine (3.0 µg/kg...
Sedative and cardiopulmonary effects of dexmedetomidine infusions randomly receiving, or not, butorphanol in standing horses. Dexmedetomidine (DEX) alone, or combined with butorphanol (BUT), may be administered by constant rate infusions (CRIs) in standing horses. This blinded, randomised, crossover study in six healthy adult horses aimed to determine the sedative and cardiopulmonary effects of DEX (dexmedetomidine (3.5 µg/kg+5 µg/kg/hour CRI) and DEX/BUT (dexmedetomidine (3.5 µg/kg+3.5 µg/kg/hour CRI) and butorphanol (20 µg/kg+24 µg/kg/hour CRI)). Head height above ground (HHAG), ataxia, responses to tactile/auditory stimuli and cardiopulmonary variables were recorded before, at 5/15/30/60/90 min...
[Effects of morphine, butorphanol and levomethadone in different doses on thermal nociceptive thresholds in horses]. Various opioids are available for use in equine medicine. Studies directly comparing their analgesic effects and side effects are rare. Therefore, the aim of this study was to compare the antinociceptive effect and the duration of analgesia of two different doses of morphine, butorphanol and levomethadone in horses. Methods: Eight adult, healthy horses were used for this randomized, placebo-controlled, blinded cross-over trail. Each horse received placebo (P = 0.9% saline) and morphine (M = 0.1 mg/kg; M = 0.2 mg/kg), butorphanol (B = 0.1 mg/kg; B = 0.2 mg/kg) and levomethadone (L...
Measurement of intraocular pressure in healthy anesthetized horses during hoisting. To measure intraocular pressure (IOP) in horses during hoisting after induction of anesthesia. Methods: Prospective nonrandomized clinical study. Methods: Eighteen healthy adult horses aged [mean±standard deviation (SD)] 10±4.2 years and weighing 491±110 kg anesthetized for elective procedures. Methods: IOP was measured in the superior eye of each horse based on planned recumbency after induction of anesthesia. Measurements were taken directly after premedication with xylazine or detomidine with butorphanol, after induction with diazepam-ketamine, after intubation, when suspended by the ho...
Incidence of post-anesthetic colic in non-fasted adult equine patients. The purpose of this study was to determine the incidence of post-anesthetic colic in non-fasted adult horses undergoing isoflurane inhalant anesthesia for an elective, non-abdominal procedure at a single referral center. Medical records were searched from May 1, 2012 to May 31, 2014. Inclusion criteria included non-fasted patients ≥ 2 years of age that were anesthetized for an elective, non-abdominal procedure. The incidence of post-anesthetic colic for this study population was 2.5%. None of the risk factors examined (season, age, gender, breed, surgeon, procedure, recumbency, butorphanol a...