Intravenous administration in horses involves the delivery of substances directly into the bloodstream through a vein. This method is used to administer fluids, medications, and nutrients efficiently, ensuring rapid distribution throughout the body. It is commonly employed in veterinary practice for rehydration, anesthesia, and treatment of various medical conditions. The technique requires skill and knowledge to ensure proper vein selection and catheter placement, minimizing the risk of complications such as infection or thrombosis. This page compiles peer-reviewed research studies and scholarly articles that explore the methodologies, applications, and potential complications associated with intravenous administration in equine medicine.
Wallace PD, Schoonover MJ, Williams MR, Maxwell LK, Taylor JD.To evaluate plasma and synovial fluid amikacin concentrations following cephalic or saphenous IV regional limb perfusion (IVRLP) with a dosing protocol of 25 mg of amikacin/kg, divided into 16.7 mg/kg systemically and 8.3 mg/kg regionally. We hypothesized that plasma amikacin concentrations observed at 30 minutes after systemic administration would exceed a therapeutic target of 53 μg/mL and that synovial fluid concentrations would exceed a therapeutic target of 80 μg/mL. Unassigned: Over a 5-month period (spring/summer of 2023), 8 healthy neonatal foals were administered each protocol at le...
Gutierrez SO, Kilcoyne I, Saldinger LK, Woodward L, Nieto JE.To determine if different methods of perfusate instillation influence synovial amikacin concentrations in the radiocarpal joint (RCJ) after IV regional limb perfusion (IVRLP). Unassigned: 6 healthy horses received an IVRLP using 2 different methods: (1) 2 g amikacin followed by 52 mL 0.9% NaCl (60 mL total; perfusate-A) and (2) 2 g amikacin diluted to 60 mL with 0.9% NaCl (perfusate-D). For both methods, the perfusion was administered over 5 minutes. Joint fluid from the RCJ was sampled at 10, 15, 20, 25, and 30 minutes after instillation of the perfusate. Systemic concentrations of amikacin w...
Munerato MS, Simon O, Nicholson A.This report describes successful cardiopulmonary resuscitation of a healthy, 525 kg, 8 years 9 months-old Quarter horse gelding. After successful pelvic limb orthopaedic surgery to excise a metatarsal bone under general anaesthesia, with the horse in left lateral recumbency, the horse was hoisted into recovery. After the horse was positioned in recovery, a routine cardiac check by thoracic auscultation was performed. Cardiopulmonary arrest (CPA) was identified by absence of cardiac sounds and pulse, as evaluated by digital palpation of the facial artery, absence of the right palpebral reflex, ...
Júnior GS, de Souza JV, de Souza Ferreira W, Florentino VRD, Valente TC, Comassetto F, Oleskovicz N.This study aimed to evaluate the sedation degree, cardiopulmonary effects, and detomidine-sparing during dental occlusal adjustment in standing horses using a bolus and constant rate infusion (CRI) of detomidine alone or in combination with butorphanol or methadone. In this randomized, blinded clinical trial, 24 healthy adult horses were assigned to the detomidine (DT), detomidine-butorphanol (DB), or detomidine-methadone (DM) group. DT received an intravenous bolus of detomidine (20 μg/kg), followed by CRI at 20 μg/kg/h. DB received detomidine (10 μg/kg) and butorphanol (0.02 mg/kg) boluse...
Bercovitz GR, Sullivan SN, Reed RA, Ryan CA, Diehl KA.To evaluate the effect of intravenous mannitol and hypertonic saline (HS) on intraocular pressure (IOP) and biometry parameters of horses with elevated intracranial pressure (ICP). Methods: Seven horses with normal ophthalmic exams were anesthetized and placed in lateral recumbency. A subarachnoid transducer was placed, and the head was lowered until ICP measured 40 mmHg +/- 2 mmHg. Five intravenous boluses of mannitol 20% (0.4 g/kg) or HS 7.2% (1 mL/kg) were administered, each 15 min apart. A 2-day washout period ensued, and the procedure was repeated with the other hyperosmotic age...
Roustaei A, Masoudifard M, Azari O, Keshipour H, Koohestani O.The effects of dexmedetomidine (DEX), as a sedative drug, on echocardiographic measurements have been investigated in many species but not in horses. Therefore, this study aimed to evaluate the echocardiographic and clinical effects of two sedative doses of DEX in healthy horses. Six female crossbred horses weighted 250-330 kg underwent echocardiography before and after sedation by intravenous administration of a low dose of 3.5 μg/kg (LD) and a high dose of 7 μg/kg (HD) of DEX. A significant increase (p≤ 0.05) was observed in the diameters of the pulmonary artery and the left atrium measu...
Larson MA, Credille BC, Berghaus LJ, Papich MG, Beasley EM.To investigate the disposition of enrofloxacin and its active metabolite, ciprofloxacin, in plasma, pulmonary epithelial lining fluid (PELF), peritoneal fluid, and CSF in horses following IV administration of enrofloxacin at doses of 5 mg/kg and 7.5 mg/kg of body weight. Unassigned: 6 healthy, mature mares were randomly assigned to receive a single dose of enrofloxacin at either 5 mg/kg or 7.5 mg/kg in a crossover design with a washout period of 10 days. Concentrations of enrofloxacin and ciprofloxacin were determined in plasma, PELF, peritoneal fluid, and CSF. Unassigned: Both doses of enrofl...
Henderson ARP, Valverde A, Marchiori J, Tisotti T, Torrent A, Côté N, Gomez DE.To determine the effects of rapid (1 minute) and slow (10 minutes) intravenous (IV) injection of sodium penicillin on arterial blood pressure in anesthetized horses. Methods: Prospective randomized clinical trial. Methods: A group of 29 client-owned horses of various breeds, 1-20 years old, with body masses of 360-710 kg. Methods: General anesthesia was induced with a variety of anesthetic protocols and maintained with isoflurane under mechanical ventilation, with hourly doses of IV lidocaine and an infusion of dexmedetomidine. Horses were administered IV intraoperative penicillin every 2 hour...
Kodaira K, Kakizaki M, Nagata SI, Ode H, Okano A, Tamura N, Mizobe F, Matsuda Y, Kurimoto S, Aida H.To investigate the pharmacodynamics and pharmacokinetics of rocuronium administered by bolus injection to sevoflurane-anesthetized horses. Methods: Prospective, experimental, crossover study. Methods: Five healthy adult Thoroughbred horses (body mass 368-470 kg, three females and two males). Methods: Each horse was anesthetized twice with sevoflurane and assigned to be administered rocuronium bromide intravenously: 0.2 mg kg (R02) or 0.4 mg kg (R04). There was a minimum 2 week washout period between experiments. During anesthesia, the peroneal nerve was stimulated (train-of-four) and neuromusc...
Mendoza FJ, Buzon-Cuevas A, Aguilera-Aguilera R, Gonzalez-De Cara CA, De Las Heras A, Perez-Ecija A.Systemic inflammatory response syndrome (SIRS) in donkeys is observed to be secondary to colic, diarrhea or pleuropneumonia, among other disorders. Horses with SIRS develop secondary disturbances such as hyperlipemia, laminitis, disseminated intravascular coagulopathy, and hemodynamic and cardiac derangements, which impair their prognosis and increase the mortality rate. In donkeys, no information is available on the effect of experimentally induced endotoxemia in the cardiovascular system. Acute experimental endotoxemia was induced by lipopolysaccharide (LPS) infusion in six healthy adult non...
Nomura M, Kuroda T, Ohta M, Kusano K, Minamijima Y, Nagata S.Salbutamol is a short-acting and selective beta-2 adrenergic agonist. Inhaled (IH) administration of salbutamol is widely used to control lower respiratory tract disease in horses. Here, we estimated the pharmacokinetic parameters of salbutamol after a single intravenous (IV) or IH administration in six horses, and we statistically analysed the detection times with various dosing regimens. Plasma and urine concentrations of salbutamol were measured by liquid chromatography-tandem mass spectrometry, and data were modelled by using a nonlinear mixed effect model followed by Monte Carlo simulatio...
Sousa LN, Winter IC, Varela DD, Luvison EZ, Guzmán JFC, Machado AMV, Figueiredo RDV, Pena GT, Dos Santos ACS, Faleiros RR, Carvalho AM.The present study involved seven horses in a randomized crossover clinical trial to evaluate the effect of lidocaine on horses with induced endotoxemia. Horses received intravenous lidocaine (1.5 mg/kg bolus, followed by 0.05 mg/kg bwt/min) or placebo (0.9% sodium chloride at the same manner) one hour before LPS administration (0.03 μg/kg, IV infusion over 30 min). We monitored clinic and hematologic parameters, abdominal auscultation, ultrasound, and pain over time. No relevant clinical differences existed between treatments regarding peristalsis, abdominal pain, or any other parameters befo...
Best ATK, Morgan JM, Burgy CLD, Flynn H, Barter LS, Cassano JM.This study aimed to evaluate the effects of including midazolam to a common equine standing sedation protocol for routine oral examination. Twelve horses underwent two examinations at least seven days apart. Horses were randomly assigned to receive midazolam intravenously (IV) (0.02mg/kg) or a placebo injection of saline (2-2.5mL IV). Five minutes later, detomidine (0.01mg/kg) and butorphanol (0.01mg/kg) were administered IV and horses were placed in standing stocks. A veterinarian blinded to the treatment protocol used a descriptive scoring system to assess degree of ataxia, acceptance of spe...
Knych HK, Blea J, Scollay M, Kass PH, McKemie DS.Ethanol, a central nervous system depressant and banned substance in horseracing, has reportedly been administered to horses prior to competition to "calm a horse's nerves." In this study, the pharmacokinetics of two metabolites of ethanol were studied to better understand the behavior of this compound in the horse and provide a scientific basis for regulation of its administration. Six horses received a single intravenous (30 mL; 1200 mg) and oral (90 mL; 3600 mg) administration of ethanol (vodka, 40% ABV) in a balanced cross-over design. Blood and urine samples were collected at vari...
Long AE, Hurcombe S, Hopster K.To compare the ability of bioreactance noninvasive cardiac output (BR-NICO) with thermodilution cardiac output (TDCO) for the measurement of cardiac output (CO) in healthy adult horses receiving 2 different IV volume replacement solutions. Methods: Prospective randomized crossover study from September to November 2021. Methods: University teaching hospital. Methods: Six university-owned adult horses. Methods: Horses were randomly assigned to receive 7.2% hypertonic saline solution (HSS) or 6% hydroxyethyl starch (130/0.4) solution (HETA). BR-NICO and TDCO were measured simultaneously at baseli...
Leduc L, Abraham M, Slack J.Atrial fibrillation (AF) is a rarely reported arrhythmia in otherwise healthy newborn foals, with a single case of cardioversion using procainamide administration described in the literature. Two neonatal Thoroughbred colts were presented to an equine hospital because of an irregularly irregular tachyarrhythmia and poor latching when trying to nurse. History, physical examination, and initial diagnostic testing including ECG and echocardiography confirmed AF without structural heart disease. The 1st foal converted into normal sinus rhythm after treatment with IV metoprolol and quinidine. The 2...
Brandon AM, Williams JM, Davis JL, Martin EG, Capper AM, Crabtree NE.To determine the pharmacokinetics (PK) of metoclopramide administered via intravenous continuous rate infusion (IV CRI) and subcutaneous (SC) bolus and evaluate for gastrointestinal motility and adverse side effects. Methods: Experimental study; randomized, crossover design. Methods: Six healthy adult horses. Methods: Each horse received metoclopramide via IV CRI (0.04 mg/kg/h for 24 h) and SC bolus (0.08 mg/kg once), with ≥1 week washout period between. Plasma was analyzed by UPLC-MS/MS. Compartmental modeling was used to determine PK parameters for each treatment; nonparametric sup...
Kilcoyne I, Nieto J, Nottle BF, Flynn H, Knych HK.Addition of morphine to the perfusate while performing intravenous regional limb perfusion (IVRLP) may be helpful in treating painful infectious orthopaedic conditions of the distal limb. Objective: The main objective of this study was to determine synovial morphine concentrations following IVRLP with morphine alone or in combination with amikacin. Methods: Randomised cross-over in vivo experiment. Methods: Six horses underwent IVRLP with 0.1 mg/kg morphine sulphate diluted to 60 mL using 0.9% NaCl (M group) or combined with 2 g amikacin and 0.9% NaCl (MA group) with a 2-week washout per...
Ferran AA, Roques BB, Chapuis L, Kuroda T, Lacroix MZ, Toutain PL, Bousquet-Melou A, Lallemand EA.Benzylpenicillin (BP) is a first-line antibiotic in horses but there are discrepancies between manufacturers and literature recommendations regarding dosing regimen. Objectives of this study were to evaluate pharmacokinetics and local tolerance of four different formulations of BP in adult horses, and to suggest optimized dosing regimen according to the formulation. Unassigned: A cross-over design was used in 3 phases for the intramuscular injection of three different products: procaine BP alone, procaine BP/ benzathine BP combination or penethamate hydriodide were administered IM in the glute...
Dupont J, Mignini B, Salciccia A, Serteyn D, Sandersen C.To compare the efficacy of inhaled salbutamol with salmeterol for the treatment of arterial hypoxaemia in anaesthetized horses. Methods: Prospective, randomized, clinical study. Methods: A total of 108 client-owned horses (American Society of Anesthesiologists status I-V) anaesthetized for elective and emergency procedures. Methods: Horses were premedicated with acepromazine [intramuscularly 0.1 mg kg or intravenously (IV) 0.05 mg kg] and xylazine (0.6 mg kg IV). Midazolam (0.06 mg kg IV) and ketamine (2.2 mg kg IV) were combined to induce anaesthesia, and isoflurane in oxygen/air mixture (ins...
Nelson GR, Mama KR, Weiner D, McKemie DS, Kass PH, Steinmetz SJ, Knych HK.This study describes the pharmacokinetics and pharmacodynamics, including antinociceptive effects, of a transdermal buprenorphine solution in horses. It was hypothesized that transdermal application would lead to sustained blood concentrations and antinociceptive effects with fewer adverse effects compared with intravenous (IV) injection. Methods: Prospective nonrandomized four-part parallel experimental study. Methods: A group of eight horses (three mares and five geldings) aged 6-12 years. Methods: Horses were administered incremental doses of 15, 30 and 45 μg kg of buprenorphine transderma...
Kuroda T, Minamijima Y, Niwa H, Mita H, Tamura N, Fukuda K, Toutain PL, Ohta M.Fosfomycin (FOM) is an approved veterinary medicinal product for large animals in Japan, but Clinical breakpoint (CBP) for antimicrobial susceptibility test (AST) is not defined for animals. This study aimed at conducting a pharmacokinetics/pharmacodynamics (PK/PD) analysis to determine the PK/PD cutoff for the CBP in horses. Drug concentrations following single intravenous administration (IV) of 20 mg/kg body weight (BW) FOM in nine horses were measured using liquid chromatography/mass spectrometry. The data were modelled using a nonlinear mixed-effects model, followed by Monte Carlo simulati...
Lacerenza MD, Arantes JA, Reginato GM, Passarelli D, Balieiro JCC, Amaral AR, Vendramini THA, Brunetto MA, Dória RGS.β-glucan is part of the cell wall of fungi and yeasts and has been known for decades to have immunomodulating effects on boosting immunity against various infections as a pathogen-associated molecular pattern that is able to modify biological responses. β-glucan has been used in rat models and in vitro studies involving sepsis and SIRS with good results, but this supplement has not been evaluated in the treatment of endotoxemia in horses. This study aims to evaluate the effects of preventive supplementation with β-glucan in horses submitted to endotoxemia by means of inflammatory response m...
Taylor SD, Hart KA, Vaughn S, Giancola SC, Serpa PBS, Santos AP.Ascorbic acid (AA) is an antioxidant that might be beneficial for adjunctive treatment of sepsis in horses. The optimal dose and effects on oxidative status are unknown. Objective: Ascorbic acid administration will increase plasma AA concentrations and decrease determinants of reactive oxygen metabolites (dROM), basal and stimulant-induced intraerythrocytic reactive oxygen species (ROS) concentrations, and stimulant-induced neutrophil ROS production, and increase plasma antioxidant capacity (PAC) in a dose-dependent manner. Methods: Eight healthy horses. Methods: Randomized placebo-controlled ...
Vorster DM, Wang W, Kemp KL, Bamford NJ, Bertin FR.The thyrotropin-releasing hormone (TRH) stimulation test is used to diagnose pituitary pars intermedia dysfunction (PPID) using 10- or 30-min protocols. Imprecise sampling time for the 10-min protocol can lead to misdiagnoses. Objective: To determine the effect of imprecise sampling time for the 30-min protocol of the TRH stimulation test. Methods: In vivo experiment. Methods: Plasma immunoreactive adrenocorticotropin (ACTH) concentrations were measured 9, 10, 11, 29, 30 and 31 min after intravenous administration of 1 mg of TRH in 15 control and 12 PPID horses. Differences in ACTH concent...
Trsan J, Nottle BF, Pusterla N.This study was designed to determine the effect of PPG and/or flunixin meglumine on SAA response when used at clinical dosing regimens in healthy adult horses. Six healthy adult horses were enrolled in a crossover study design including one control and three treatment groups: no treatment (control); PPG alone (intramuscularly q12h for 72h); flunixin meglumine alone (intravenously q24h for 72h); and PPG (intramuscularly q12h for 72h) and flunixin meglumine (intravenously q24h for 72h). Whole blood was collected at 0, 24, 48, 72, 96 and 120 hours post-initial drug administration to measure SAA u...
Acutt EV, Zhou T, Mama K, Nelson BB, Selberg KT, Barrett MF.Delivery of mesenchymal stem cells (MSC) via intravascular techniques to treat diffuse and/or inaccessible soft tissue injuries has grown in popularity. The purpose of the current prospective, analytical pilot study was to utilize CT to validate this novel technique and provide additional evidence to support its use for injectate delivery to specific soft tissue structures. Of particular interest was the proximal suspensory ligament, which presents a challenging injection target. Six adult horses without lameness underwent CT of the distal hindlimbs. Scans were obtained prior to ultrasound-gui...
Haugaard SL, McGovern KF, Tallon R, Gough R, Watrobska N.Horses commonly receive hyoscine butylbromide (HB) prior to hospital admission for colic. This could alter the appearance of the small intestine (SI) on ultrasound scan and affect clinical decision making. The aim of this study was to assess the impact of HB on ultrasonographically assessed SI motility and heart rate. Six horses hospitalised for medical colic with no significant abnormalities on baseline abdominal ultrasound examination were included. Ultrasound was performed in three locations (right inguinal, left inguinal and hepatoduodenal window) before and at 1, 5, 15, 30, 45, 60, 90, an...
McLean AK, Falt T, Abdelfattah EM, Middlebrooks B, Gretler S, Spier S, Turoff D, Navas Gonzalez FJ, Knych HK.Recent approval of transdermal flunixin meglumine (FM) (Banamine®) in cattle has opened the door for the drug's potential application in other species. Transdermal FM could provide a safe and effective form of pain relief in donkeys. In order to evaluate the pharmacokinetics and effects of FM on anti-inflammatory biomarkers in donkeys, a three-way crossover study design was employed. In total, 6 healthy donkeys were administered transdermal (TD) FM at a dosage of 3.3 mg/kg, and oral (PO) and intravenous (IV) doses of 1.1 mg/kg body weight. Blood samples were collected over 96 h to determine t...
Frers F, Delarocque J, Huber K, Feige K, Warnken T.Both, oral and intravenous (IV) testing protocols, are recommended and still used to detect insulin dysregulation (ID) in equids. However, IV tests mainly focus on peripheral insulin resistance (IR), while oral tests assess hyperinsulinemia (HI), which are different aspects of ID. The objective of this study was to describe if horses with HI also demonstrate IR and consequently can be detected by a modified 2-step insulin response test (2-step IRT) performed with a veterinary approved porcine zinc insulin (PZI). Twelve Icelandic horses were subjected to an OGT and 2-step IRT in a crossover stu...
Klöppel H, Leece EA.To compare alfaxalone with ketamine for total intravenous anaesthesia in ponies undergoing castration. Methods: Prospective, randomised, blinded clinical study. Methods: Forty-two, 12-month-old Welsh Mountain ponies. Methods: Ponies were assigned randomly to receive ketamine or alfaxalone. After administration of romifidine 100 μg kg(-1) and butorphanol 50 μg kg(-1) intravenously (IV), sedation and response to tactile stimulation were scored. If sedation was insufficient, romifidine 30 μg kg(-1) was administered IV. Anaesthesia was induced with ketamine 2.2 mg kg(-1) or alfaxalone 1 mg kg(-...
Costa GL, Cristarella S, Quartuccio M, Interlandi C.To evaluate the anti-nociceptive and sedative effects of slow intravenous (IV) injection of tramadol, romifidine, or a combination of both drugs in ponies. Methods: Within-subject blinded. Methods: Twenty ponies (seven male, 13 female, weighing mean ± SD 268.0 ± 128 kg). Methods: On separate occasions, each pony received one of the following three treatments IV; romifidine 50 μg kg(-) (R) tramadol 3 mg kg(-1) given over 15 minutes (T) or tramadol 3 mg kg(-1) followed by romifidine 50 μg kg(-1) (RT). Physiologic parameters and caecal borborygmi (CB) were measured and sedation ...
Terry RL, McDonnell SM, Van Eps AW, Soma LR, Liu Y, Uboh CE, Moate PJ, Driessen B.Gabapentin is being used in horses although its pharmacokinetic (PK) profile, pharmacodynamic (PD) effects and safety in the equine are not fully investigated. Therefore, we characterized PKs and cardiovascular and behavioral effects of gabapentin in horses. Gabapentin (20 mg/kg) was administered i.v. or p.o. to six horses using a randomized crossover design. Plasma gabapentin concentrations were measured in samples collected 0-48 h postadministration employing liquid chromatography-tandem mass spectrometry. Blood pressures, ECG, and sedation scores were recorded before and for 12 h after gaba...
Valverde A, Gunkelt C, Doherty TJ, Giguère S, Pollak AS.Lidocaine constant rate infusions (CRIs) are common as an intraoperative adjunct to general anaesthesia, but their influence on quality of recovery has not been thoroughly determined. Objective: To determine the effects of an intraoperative i.v. CRI of lidocaine on the quality of recovery from isoflurane or sevoflurane anaesthesia in horses undergoing various surgical procedures, using a modified recovery score system. Objective: The administration of intraoperative lidocaine CRI decreases the quality of recovery in horses. Methods: Lidocaine (2 mg/kg bwt bolus followed by 50 microg/kg bwt/min...
Broeckx S, Borena BM, Zimmerman M, Mariën T, Seys B, Suls M, Duchateau L, Spaas JH.It has been reported that mesenchymal stem cells (MSCs) have homing capacities and immunomodulating effects after an intravenous injection. However, transplanting MSCs in murine tail veins can result in pulmonary reactions and even death of the animals. Unfortunately, only a few intravenous MSC transplantations have been reported in large animal species and these were performed in a limited number of individuals. To assess the safety of MSC transplantations, a large study on 291 recipient horses is reported here. MSCs were isolated from the peripheral blood (PB) of a 4-year-old and 6-year-old ...
Rezende ML, Grimsrud KN, Stanley SD, Steffey EP, Mama KR.The aim of the study was to describe the pharmacokinetics and selected pharmacodynamics of intravenous dexmedetomidine in horses. Eight adult horses received 5 μg/kg dexmedetomidine IV. Blood samples were collected before and for 10 h after drug administration to determine dexmedetomidine plasma concentrations. Pharmacokinetic parameters were calculated using noncompartmental analysis. Data from one outlier were excluded from the statistical summary. Behavioral and physiological responses were recorded before and for 6 h after dexmedetomidine administration. Dexmedetomidine concentrations dec...
Williams LB, Co C, Koenig JB, Tse C, Lindsay E, Koch TG.Equine mesenchymal stromal cells (MSC) are commonly transported, chilled or frozen, to veterinary clinics. These MSC must remain viable and minimally affected by culture, transport, or injection processes. The safety of two carrier solutions developed for optimal viability and excipient use were evaluated in ponies, with and without allogeneic cord blood-derived (CB) MSC. We hypothesized that neither the carrier solutions nor CB-MSC would elicit measurable changes in clinical, hematological, or biochemical parameters. In nine ponies (study 1), a bolus of HypoThermosol(®) FRS (HTS-FRS), CryoSt...
Murrell JC, White KL, Johnson CB, Taylor PM, Doherty TJ, Waterman-Pearson AE.To record the electroencephalographic changes during castration in ponies anaesthetized with halothane and given intravenous (IV) lidocaine by infusion. The hypothesis tested was that in ponies, IV lidocaine is antinociceptive and would therefore obtund EEG changes during castration. Methods: Ten Welsh mountain ponies referred to the Department of Clinical Veterinary Medicine, Cambridge for castration under general anaesthesia. Methods: Following pre-anaesthetic medication with intramuscular acepromazine (0.02 mg kg(-1)) anaesthesia was induced with IV guaiphenesin (60 mg kg(-1)) and thiopenta...
Sellon DC, Monroe VL, Roberts MC, Papich MG.To determine an infusion rate of butorphanol tartrate in horses that would maintain therapeutic plasma drug concentrations while minimizing development of adverse behavioral and gastrointestinal tract effects. Methods: 10 healthy adult horses. Methods: Plasma butorphanol concentrations were determined by use of high-performance liquid chromatography following administration of butorphanol by single IV injection (0.1 to 0.13 mg/kg of body weight) or continuous IV infusion (loading dose, 17.8 microg/kg; infusion dosage, 23.7 microg/kg/h for 24 hours). Pharmacokinetic variables were calculated, a...
Hamamoto-Hardman BD, Steffey EP, Weiner D, McKemie DS, Kass P, Knych HK.The objective of the current study was to describe and characterize the pharmacokinetics and selected pharmacodynamic effects of morphine and its two major metabolites in horses following several doses of morphine. A total of ten horses were administered a single intravenous dose of morphine: 0.05, 0.1, 0.2, or 0.5 mg/kg, or saline control. Blood samples were collected up to 72 hr, analyzed for morphine, and metabolites by LC/MS/MS, and pharmacokinetic parameters were determined. Step count, heart rate and rhythm, gastrointestinal borborygmi, fecal output, packed cell volume, and total prote...
Rohrbach H, Korpivaara T, Schatzmann U, Spadavecchia C.To evaluate and compare the antinociceptive effects of the three alpha-2 agonists, detomidine, romifidine and xylazine at doses considered equipotent for sedation, using the nociceptive withdrawal reflex (NWR) and temporal summation model in standing horses. Methods: Prospective, blinded, randomized cross-over study. Methods: Ten healthy adult horses weighing 527-645 kg and aged 11-21 years old. Methods: Electrical stimulation was applied to the digital nerves to evoke NWR and temporal summation in the left thoracic limb and pelvic limb of each horse. Electromyographic reflex activity was reco...
Magdesian KG, Hogan PM, Cohen ND, Brumbaugh GW, Bernard WV.To evaluate pharmacokinetics of a high dose of gentamicin administered i.v. or i.m. to horses. Methods: Repeated-measures study. Methods: 6 clinically normal female adult stock-type horses. Methods: All horses were given gentamicin (6.6 mg/kg [3 mg/lb] of body weight), i.v. and i.m., in a two-way cross-over design. Serum gentamicin concentrations were measured during a 24-hour period. Results: Plasma concentration curves were consistent with a two-compartment model. Maximum plasma gentamicin concentrations were 71.9 +/- 15.7 micrograms/ml (0 hours after injection) and 22.0 +/- 4.9 micrograms/m...
Yamazaki M, Kusano K, Ishibashi T, Kiuchi M, Koyama K.Upon intensive, exhaustive exercise, exercise-induced reactive oxygen species may exceed the antioxidant defence threshold, consequently resulting in muscular damage or late-onset chronic inflammation. Recently, the therapeutic antioxidant and anti-inflammatory effects of molecular hydrogen (H2) for human rheumatoid arthritis have been demonstrated. However, it is also important to clarify the effects of administrating H2 in large animals other than humans, as H2 is thought to reach the target organ by passive diffusion upon delivery from the blood flow, indicating that the distance from the a...
Malone E, Ensink J, Turner T, Wilson J, Andrews F, Keegan K, Lumsden J.To determine if intravenous lidocaine is useful and safe as a treatment for equine ileus. Methods: Prospective double-blinded placebo-controlled trial. Methods: Horses (n = 32) with a diagnosis of postoperative ileus (POI) or enteritis and that had refluxed >20 L or had been refluxing for >24 hours. Methods: Refluxing horses were administered lidocaine (1.3 mg/kg intravenously [IV] as a bolus followed by a 0.05 mg/kg/min infusion) or saline (0.9% NaCl) solution placebo for 24 hours. Variables evaluated included volume and duration of reflux, time to 1st fecal passage, signs of pain, anal...
Muir WW, Skarda RT, Milne DW.The cardiopulmonary effects resulting from the combination of xylazine and ketamine hydrochloride were evaluated in the adult horse. Xylazine (1.1 mg mg/kg) administered intravenously prior to or simultaneously with ketamine hydrochloride (2.2 mg/kg; intravenous) provided excellent analgesia and light anesthesia in all horses. Cardiac output, arterial blood pressure, pulmonary arterial pressure, central venous pressure, and pulmonary arterial wedge pressure remained within normal limits for the adult horse. Evidence of respiratory acidosis developed with time during the anesthetic period. Indu...
Grimsrud KN, Mama KR, Steffey EP, Stanley SD.To describe the pharmacodynamics and pharmacokinetics following an intravenous (IV) bolus dose of medetomidine in the horse. Methods: Prospective experimental trial. Methods: Eight, mature healthy horses age 11.7 ± 4.6 (mean ± SD) years, weighing 557 ± 54 kg. Methods: Medetomidine (10 μg kg(-1) ) was administered IV. Blood was sampled at fixed time points from before drug administration to 48 hours post administration. Behavioral, physiological and biochemical data were obtained at predetermined time points from 0 minutes to 24 hours post administration. An algometer was also used to measu...
Garré B, Shebany K, Gryspeerdt A, Baert K, van der Meulen K, Nauwynck H, Deprez P, De Backer P, Croubels S.The purpose of this study was twofold. The first aim was to evaluate the oral bioavailability and pharmacokinetics (PKs) of acyclovir in horses after intravenous (i.v.) administration and after oral administration of acyclovir and its prodrug, valacyclovir. Second, we aimed to combine these PK data with pharmacodynamic (PD) information, i.e., 50% effective concentrations (EC(50) values) from in vitro studies, to design an optimal dosage schedule. Three treatments were administered to healthy adult horses: 10 mg of acyclovir/kg of body weight delivered as an i.v. infusion over 1 h, 20 mg of acy...
Scheuch BC, Van Hoogmoed LM, Wilson WD, Snyder JR, MacDonald MH, Watson ZE, Steffey EP.To establish the route of infusion (IV or intraosseous) that results in the highest concentration of amikacin in the synovial fluid of the tibiotarsal joint and determine the duration of peak concentrations. Methods: 21 horses. Methods: Regional perfusion of a limb on 15 horses was performed. Amikacin sulfate was infused into the saphenous vein or via intraosseous infusion into the distal portion of the tibia (1 g in 56 ml of lactated Ringer's solution) or proximal portion of the metatarsus (1 g of amikacin in 26 ml of lactated Ringer's solution). Amikacin concentrations were measured in seque...
Soma LR, Uboh CE, You Y, Guan F, Boston RC.To compare pharmacokinetics of triamcinolone acetonide (TA) following i.v., intra-articular (i.a.), and i.m. administration and determine its effect on plasma concentrations of hydrocortisone and cortisone. Methods: 6 Thoroughbreds. Methods: TA (0.04 mg/kg) was administered i.v., i.m., or i.a., and plasma TA, hydrocortisone, and cortisone concentrations were determined. Results: I.v. administration of TA was fitted to a 2-compartment model. Median distribution half-life was 0.50 hours (range, 0.24 to 0.67 hours); elimination half-life was 6.1 hours (range, 5.0 to 6.4 hours). Transfer half-life...
van Loon G, Blissitt KJ, Keen JA, Young LE.It has been reported that i.v. flecainide has a high efficacy for the treatment of experimentally-induced acute atrial fibrillation (AF) in horses and that its use is associated with minimal toxic side effects. Objective: The objectives were to study the efficacy of i.v. flecainide as a treatment for atrial fibrillation in horses with naturally-occurring AF. Methods: Ten horses with naturally-occurring AF were treated with 2 mg/kg bwt flecainide i.v. at a rate of 0.2 mg/kg bwt/min. In 3 horses, the infusion was continued at 0.05-0.10 mg/kg bwt/min until a total dose of 3.0 mg/kg bwt had been a...
Kerr CL, McDonell WN, Young SS.The purpose of this study was to compare and evaluate sedation with intravenous xylazine (1.1 mg/kg bodyweight [BW]) versus intravenous romifidine (100 micrograms/kg BW) followed by induction of anesthesia with intravenous diazepam (0.04 mg/kg BW) and ketamine (2.2 mg/kg BW). Twelve healthy horses were used in a blinded, randomized, cross-over design. Heart rate, presence of 2nd degree atrioventricular heart blocks (2 degrees AVB), respiratory rate, arterial blood pressures, blood gases, packed cell volume, total serum proteins, and duration of anesthesia and recumbency were recorded. Inductio...
Gozalo-Marcilla M, Gasthuys F, Schauvliege S.To review the literature with regard to the use of different intravenous agents as supplements to inhalational anaesthesia in horses. These drugs include lidocaine, ketamine, opioids and α2 -agonists. The Part 1 of this review will focus in the use of lidocaine and ketamine. Methods: Pubmed & Web of Science. Search terms: horse, inhalant anaesthesia, balanced anaesthesia, partial intravenous anaesthesia, lidocaine, ketamine. Conclusions: Different drugs and their combinations can be administered systemically in anaesthetized horses, with the aim of reducing the amount of the volatile agen...
Tóth F, Frank N, Elliott SB, Geor RJ, Boston RC.To evaluate the effects of endotoxin administered IV on glucose and insulin dynamics in horses. Methods: 16 healthy adult mares. Methods: Each week of a 2-week randomized crossover study, each horse received an IV injection (duration, 30 minutes) of Escherichia coli O55:B5 lipopolysaccharide (LPS) in 60 mL of sterile saline (0.9% NaCl) solution (20 ng/kg) or sterile saline solution alone (control treatment). Frequently sampled IV glucose tolerance test procedures were performed at 24 hours before (baseline) and 24 and 48 hours after injection; glucose and insulin dynamics were assessed via min...
Toutain PL, Brandon RA, de Pomyers H, Alvinerie M, Baggot JD.Pharmacokinetics of dexamethasone and prednisolone were studied in 6 horses given dexamethasone alcohol (IV or IM) or dexamethasone 21-isonicotinate as a solution IV or IM (50 micrograms/kg of body weight), prednisolone 21-sodium succinate IV or IM (0.6 mg/kg of body weight), or prednisolone acetate IM (0.6 mg/kg of body weight). Plasma concentrations were determined using a high-performance liquid chromatographic method. After dexamethasone alcohol (IV) or dexamethasone 21-isonicotinate (IV), the half-life of elimination was similar (53 minutes) for both formulations. After dexamethasone (alc...
Muir WW, Ueyama Y, Noel-Morgan J, Kilborne A, Page J.To evaluate the quality of the veterinary literature investigating IV fluid therapy in dogs, cats, horses, and cattle. Methods: Systematic review. Methods: The preferred reporting of items for systematic review and meta-analysis protocols (PRISMA-P) was employed for systematic review of all relevant IV fluid therapy manuscripts published from January 1969 through December 2016 in the Commonwealth Agricultural Bureaux International (CABI) database. Independent grading systems used to evaluate manuscripts included the updated CONsolidated Standards of Reporting Trials 2012 checklist, risk of bia...
Soma LR, Uboh CE, Liu Y, Li X, Robinson MA, Boston RC, Colahan PT.This study investigated and compared the pharmacokinetics of intra-articular (IA) administration of dexamethasone sodium phosphate (DSP) into three equine joints, femoropatellar (IAS), radiocarpal (IAC), and metacarpophalangeal (IAF), and the intramuscular (IM), oral (PO) and intravenous (IV) administrations. No significant differences in the pharmacokinetic estimates between the three joints were observed with the exception of maximum concentration (Cmax ) and time to maximum concentration (Tmax ). Median (range) Cmax for the IAC, IAF, and IAS were 16.9 (14.6-35.4), 23.4 (13.5-73.0), and 46.9...
Knych HK, Steffey EP, McKemie DS.The objective of the current study was to describe the pharmacokinetics of morphine and its metabolites following intravenous administration to the horse. A total of eight horses (two per dose group) received a single intravenous dose of 0.05, 0.1, 0.2, or 0.5 mg/kg morphine. Blood samples were collected up to 72 h postdrug administration, analyzed using LC-MS/MS and pharmacokinetic parameters determined. Behavior, step counts, and gastrointestinal activity were also assessed. The beta and gamma half-life for morphine ranged from 0.675 to 2.09 and 6.70 to 18.1 h, respectively, following admini...
Doherty TJ, Frazier DL.This study investigated the effect of lidocaine i.v. on halothane minimum alveolar concentration (MAC) in ponies. Six ponies were anaesthetised with thiopentone and succinylcholine, intubated and anaesthesia maintained with halothane. Ventilation was controlled and blood pressure maintained within clinically acceptable limits. Following a 2 h equilibration period, baseline halothane MAC was determined. The ponies were then given a loading dose of lidocaine (2.5 or 5 mg/kg bwt) or saline over 5 min, followed by a constant infusion of lidocaine (50 or 100 microg/kg/min, or saline, respectively)....
Brianceau P, Chevalier H, Karas A, Court MH, Bassage L, Kirker-Head C, Provost P, Paradis MR.Twenty-eight horses with the diagnosis of an intestinal disorder requiring surgical intervention were randomly assigned to lidocaine (n = 13) or saline (control, n = 15) treatment groups. After induction of anesthesia, treated horses received a loading dose of 2% lidocaine (0.65 mg/kg) intravenously, followed by a continuous rate of infusion of 1% lidocaine (0.025 mg/kg/min) until the discontinuation of anesthesia. Upon recovery from anesthesia, a 2nd loading dose of 2% lidocaine (1.3 mg/kg) was administered, followed by an infusion of 1% lidocaine (0.05 mg/kg/min) for 24 hours postoperatively...
Levine DG, Epstein KL, Ahern BJ, Richardson DW.To determine (1) if clinically useful concentrations of amikacin sulfate can be obtained in synovial fluid during regional limb perfusion (RLP) performed above the carpus in standing sedated horses and (2) to determine the efficacy of 3 tourniquet types (narrow rubber [NR], wide rubber [WR], pneumatic [PN]). Methods: Horses (n=9). Methods: Bilateral forelimb RLP with amikacin sulfate (2.5 g) were administered through the cephalic vein in standing sedated horses. Limbs were randomly assigned to the 3 tourniquet types (NR, WR, PN) applied above the carpus. Metacarpophalangeal synovial fluid was ...
