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.
Kimura S, McCoy AM, Boothe DM, Wooldridge AA, Graff E, Hammack SM, Cresci L, Hofmeister E, Lascola KM.To describe misoprostol pharmacokinetics and anti-inflammatory efficacy when administered orally or per rectum in endotoxin-challenged horses. Methods: 6 healthy geldings. Methods: A randomized 3-treatment crossover design was performed with a minimum washout period of 28 days between treatment arms. Prior to endotoxin challenge (lipopolysaccharide, 30 ng/kg IV over 30 minutes), horses received misoprostol (5 µg/kg once) per os (M-PO) or per rectum (M-PR) or water as control (CON). Clinical parameters were evaluated and blood samples obtained to measure plasma misoprostol free acid concentrat...
Taylor SD, Serpa PBS, Santos AP, Hart KA, Vaughn SA, Moore GE, Mukhopadhyay A, Page AE.A systemic and dysregulated immune response to infection contributes to morbidity and mortality associated with sepsis. Peripheral blood-derived mesenchymal stromal cells (PB-MSC) mitigate inflammation in animal models of sepsis. Allogeneic PB-MSC administered IV to horses is well-tolerated but therapeutic benefits are unknown. Objective: After IV lipopolysaccharide (LPS) infusion, horses treated with PB-MSC would have less severe clinical signs, clinicopathological abnormalities, inflammatory cytokine gene expression, and oxidative stress compared to controls administered a placebo. Methods: ...
Doerffel A, Reinert A, Böttcher D, Winter K, Brehm W, Gittel C.Complications associated with indwelling intravenous catheters vary from minor to severe. Changes in tissue architecture and vein structure may be detectable prior to clinical alterations. The aim of the study was to characterize and compare changes in a catheterized vein and surrounding tissue by clinical and ultrasonographic examination. Microbiological infestation of catheter specimens was assessed. Methods: In this prospective, observational, clinical study 55 horses with an indwelling intravenous catheter have been included. Subsequent to catheter placement, vein and surrounding tissue we...
Liepman RS, Swink JM, Habing GG, Boyaka PN, Caddey B, Costa M, Gomez DE, Toribio RE.Alterations in the gastrointestinal microbiota after antimicrobial therapy in horses can result in loss of colonization resistance and changes in bacterial metabolic function. It is hypothesized that these changes facilitate gastrointestinal inflammation, pathogen expansion and the development of diarrhea. The objectives of this study were to determine the effect of intravenous administration of antimicrobial drugs (ceftiofur, enrofloxacin, oxytetracycline) on equine fecal bacterial communities over time, to investigate whether those changes are detectable after 5 days of treatment and whether...
Haughan JE, Missanelli JR, You Y, Stefanovski D, Soma LR, Robinson MA.Glaucine, an aporphine alkaloid with anti-tussive, anti-inflammatory, and anti-nociceptive properties, has been identified in post-race samples from racehorses. To investigate pharmacokinetics of glaucine in horses, a three-way crossover study of intravenous and oral glaucine (0.1 mg/kg) and orally administered tulip poplar shavings (50 g shavings = 0.001 mg/kg glaucine) was performed in six horses. A two-compartment model best described IV administration with alpha ( ) and beta ( ) half-life lives of 0.3 (0.1-0.7) and 3.1 (2.4-7.8) h, respectively. The area under the curve ( ) was ...
Gustafsson K, Tatz AJ, Britzi M, Dahan R, Sutton GA, Kelmer G.Eight horses underwent IVRLP at two occasions through a 23-gauge 2 cm long butterfly catheter. Regional anaesthesia of the ulnar, median and medial cutaneous antebrachial nerves was performed prior, and an 8 cm rubber tourniquet was placed on the proximal radius for 30 minutes following the infusion. The first infusion consisted of 2 g of amikacin sulphate and 10 mg of dexamethasone phosphate diluted with 0.9% NaCl to a total volume of 100 ml. The second perfusion was performed after a 2-week washout period, the same protocol was used but without dexamethasone phosphate. Synovial fluid s...
Hopster K, Watkins AR, Hurcombe SD.To compare the antinociceptive effects of morphine administered via cervical epidural catheter to intravenously administered morphine using a thermal threshold (TT) testing model in healthy adult horses. Methods: Prospective, randomized, blinded experimental study. Methods: A total of six university-owned adult horses. Methods: Horses were instrumented with a cervical (C1-C2) epidural catheter and TT testing device with probes at withers and thoracic limb coronary bands. All horses underwent three TT testing cycles including cervical epidural morphine administration (treatment EpiM; 0.1 mg kg-...
Jurek KA, Schoonover MJ, Williams MR, Rudra P.To determine the influence of perfusate volume on synovial fluid amikacin concentrations in the joints of the hind limb after standing saphenous intravenous regional limb perfusion (IVRLP). Methods: Randomized crossover design. Methods: Six adult horses. Methods: Saphenous IVRLP was performed in 6 standing horses with 1 g of amikacin diluted with 0.9% NaCl to volumes of 10 ml, 60 ml, and 120 ml. Samples of synovial fluid from the tarsocrural, metatarsophalangeal, and hind limb distal interphalangeal joints were collected at 15 and 30 min after perfusate administration. Concentrations ...
Ekstrand C, Nostell K, Gehring R, Bondesson U, Bröjer J.Septicaemia in the neonatal foal is caused by both Gram positive and Gram negative bacteria. The life-threatening nature of this condition requires treatment to be initiated with broad spectrum antimicrobial drugs pending antimicrobial susceptibility testing. Potentiated sulphonamides, for example, trimethoprim combined with sulfadiazine, could be clinically relevant options but their pharmacokinetics in the neonatal foal are unknown. To describe the plasma disposition of trimethoprim and sulfadiazine in neonatal foals and to relate the results to patterns in the minimum inhibitory concentrati...
Muñoz KA, Szarek M, Manfredi JM, Robertson SA, Hubbell JA, Holcombe SJ.To determine the effects of intravenous ethyl pyruvate, an anti-inflammatory with putative benefits in horses with endotoxemia, on cardiopulmonary variables during anesthesia and the quality of anesthetic recovery. Methods: Randomized, crossover, blinded experimental design. Methods: A total of six healthy Standardbred geldings, aged 13 ± 3 years and weighing 507 ± 66 kg (mean ± standard deviation). Methods: Horses were anesthetized for approximately 90 minutes on two occasions with a minimum of 2 weeks apart using xylazine for sedation, ketamine and diazepam for induction, and isoflurane i...
Bergstrom TC, Kilcoyne I, Magdesian KG, Nieto JE.To determine whether IV regional limb perfusion (IVRLP) performed in the cephalic vein with a wide rubber tourniquet (WRT) applied proximal and distal to the carpus results in a higher peak concentration (Cmax) of amikacin in the radiocarpal joint (RCJ), compared with the Cmax for IVRLP using a single WRT proximal to the carpus. Methods: 7 healthy adult horses. Methods: Horses underwent IVRLP using standing sedation with 2 g of amikacin sulfate diluted to 60 mL by use of saline (0.9% NaCl) solution in the cephalic vein with 2 different tourniquet techniques; proximal WRT (P) and proximal and d...
Kinsella HM, Hostnik LD, Snyder HA, Mazur SE, Kamr AM, Burns TA, Mossbarger JC, Toribio RE.The equine neonate is considered to have impaired glucose tolerance due to delayed maturation of the pancreatic endocrine system. Few studies have investigated insulin sensitivity in newborn foals using dynamic testing methods. The objective of this study was to assess insulin sensitivity by comparing the insulin-modified frequently sampled intravenous glucose tolerance test (I-FSIGTT) between neonatal foals and adult horses. This study was performed on healthy neonatal foals (n = 12), 24 to 60 hours of age, and horses (n = 8), 3 to 14 years of age using dextrose (300 mg/kg IV) and insulin (0....
Redmond JS, Stang BV, Schlipf JW, Christensen JM.Diphenhydramine is an H1 receptor antagonist used to control urticaria and other allergic signs caused by type I hypersensitivity reactions in horses (Equus caballus). Limited studies have been conducted on pharmacokinetics of this drug in horses, with no studies involving oral formulations. Our study investigated pharmacokinetics of an oral diphenhydramine formulation compared to intravenous administration in non-fasted adult horses. Six healthy horses underwent a single administration of three different doses of diphenhydramine (1 mg/kg intravenously, 1 mg/kg intragastrically, and 5 mg/kg...
Luethy D, Robinson MA, Stefanovski D, Haughan J, Torcivia C, Kowalski A, Ford M, You Y, Missanelli J, Slack J.Cardiac drugs with defined pharmacological parameters in horses are limited. The objective of this study was to characterize the pharmacokinetic properties and cardiovascular effects of intravenous and oral metoprolol tartrate (MET) in horses. In a 2-period randomized cross-over design, MET was administered IV (0.04 mg/kg) and PO (6 mg/kg) once to six healthy adult horses. Horses were monitored via continuous telemetry and non-invasive blood pressure (NIBP). Blood samples were serially collected for 72 h post-administration, and concentrations were determined by LC-MS/MS. Pharmacokinetics w...
Mund SJK, MacPhee DJ, Campbell J, Honaramooz A, Wobeser B, Barber SM.Limb wounds are common in horses and often develop complications. Intravenous multipotent mesenchymal stromal cell (MSC) therapy is promising but has risks associated with intravenous administration and unknown potential to improve cutaneous wound healing. The objectives were to determine the clinical safety of administering large numbers of allogeneic cord blood-derived MSCs intravenously, and if therapy causes clinically adverse reactions, accelerates wound closure, improves histologic healing, and alters mRNA expression of common wound cytokines. Wounds were created on the metacarpus of 12 ...
de Souza Garcia AF, Ribeiro G, de Assis Arantes J, Reginato GM, Xavier NV, Carregaro AB, Silva TJF, Grigoletto R, de Freitas SH, Dória RGS.For horses requiring prolonged daily cephalic intravenous regional limb perfusion (IVRLP), the use of a totally implantable catheter (TIC) could be indicated to reduce complications associated with frequent venipuncture or external catheterization. This study aims to evaluate the implantation technique of the TIC in the cephalic vein of horses for IVRLP, describe the complications associated with the device's placement and use, and assess its viability up to 60 days after implantation. Totally implantable catheters, cut to 15 cm (n = 5) and 46 cm (n = 5) in length, were implanted...
Giusto G, Vercelli C, Gandini M.There are few guidelines for the appropriate mode of fluid administration during and after colic surgery, and is challenging to reach the right balance while avoiding overhydration. This study aimed to compare goal-directed fluid therapy (GDFT) and 'liberal' fluid regimens (LFRs) in horses undergoing small intestinal surgery. Methods: Eighteen horses subjected to small intestinal surgery were matched according to the surgical lesion, type of anastomosis, length of resection, and duration of clinical signs. Horses in the LFR group were administered intravenous (IV) fluids for at least 24 h. In ...
Hector RC, Rezende ML, Nelson BB, Monnet E.Endotoxaemia causes untoward inflammatory-mediated effects that might be attenuated by dexmedetomidine. Objective: To evaluate the effects of a dexmedetomidine intravenous (IV) infusion on systemic and intestinal haemodynamics and arterial blood gas values in sevoflurane-anaesthetised horses administered Escherichia coli O55:B5 lipopolysaccharides (LPS). Methods: Randomised controlled in vivo experiment. Methods: A total of 13 horses weighing 456 ± 86 kg (mean ± standard deviation) and aged 13.9 ± 9.0 years donated for euthanasia underwent ventral midline celiotomy using sevoflurane...
Bonilla AG, Causeret L, Torrent-Crosa A.This study investigated the pharmacokinetics of ceftiofur after intravenous regional limb perfusion (IVRLP). Six horses were involved in 3 IVRLP sessions. For each session, operators with varying clinical experience placed the tourniquet. A wide-rubber tourniquet was applied in the antebrachium as 2 g of ceftiofur in a total volume of 100 mL was injected into the cephalic vein. Plasma and metacarpophalangeal synovial fluid samples were obtained to evaluate perfusate leakage and synovial fluid concentrations of ceftiofur over 24 h. Overall, mean plasma concentrations were not significantly diff...
Jarosinski SK, Simon BT, Hatfield R, Matthews NS, Arnold CE.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. Horse...
Nannarone S, Giannettoni G, Laurenza C, Giontella A, Moretti G.While butorphanol is the most commonly used opioid in horses, methadone is not licensed in most countries. Our aim was to compare the effects of both drugs, combined with romifidine, regarding the quality of sedation and induction in horses undergoing elective surgery. Results indicate the suitability of both methadone and butorphanol in this patient population. Animals were scored 10 min after intravenous injection of sedatives. Despite lower overall sedation (OS) score in horses receiving methadone (p = 0.002), the quality and time of induction and intubation remained unchanged. None of the ...
Bertuglia A, Basano I, Pagliara E, Bottegaro NB, Spinella G, Bullone M.To compare the effects of tiludronate disodium and 3 other medical treatments on clinical and radiographic findings and biomarkers of disease progression in horses with osteoarthritis of the fetlock joint. 100 Standardbred racehorses with spontaneous traumatic injury of the fetlock joint. Horses were retrospectively grouped by whether they received tiludronate IV or triamcinolone acetonide and hyaluronan, polysulfated glycosaminoglycan, or interleukin-1 receptor antagonist protein intra-articularly. Data were collected on clinical, radiographic, and ultrasonographic findings and results for se...
Yılmaz İ, Maraş Z, Uğur Y, Erkan Özgür M, Durmaz M, İbrahim Ulusoy H, Erdoğan S.Metamizole sodium (MT) is an analgesic and antipyretic drug molecule used in humans, horses, cattle, swine, and dogs. Metamizole rapidly hydrolyzes and turns into methylamino antipyrine (MAA), an active primary metabolite of MT. The present study aims to determine the pharmacokinetic (PK) profiles of MT metabolites after intravenous (IV) and intramuscular (IM) administration into sex of Arabian horses (Equus ferus caballus) using a cross-over study design. The plasma samples were extracted by solid-phase extraction (SPE) method, and plasma concentrations of MT metabolites were analyzed by high...
McReynolds CB, Yang J, Guedes A, Morisseau C, Garcia R, Knych H, Tearney C, Hamamoto B, Hwang SH, Wagner K, Hammock BD.There are few novel therapeutic options available for companion animals, and medications rely heavily on repurposed drugs developed for other species. Considering the diversity of species and breeds in companion animal medicine, comprehensive PK exposures in the companion animal patient is often lacking. The purpose of this paper was to assess the pharmacokinetics after oral and intravenous dosing in domesticated animal species (dogs, cats, and horses) of a novel soluble epoxide hydrolase inhibitor, EC1728, being developed for the treatment of pain in animals. Results: Intravenous and oral adm...
Hess EK, Reinhart JM, Anderson MJ, Jannasch AS, Taylor SD.Thiamine is a vital co-factor for several anti-inflammatory and antioxidant processes that are critical for mitigation of sepsis-associated inflammation, but pharmacokinetic (PK) analysis has not been reported in horses. We hypothesized that IV thiamine hydrochloride (TH) at increasing dosages would result in corresponding increases in plasma thiamine concentrations without causing adverse effects. A randomized cross-over study was performed in 9 healthy horses that each received TH at 5, 10, and 20 mg/kg IV. Blood was collected immediately prior to drug administration and at several time poi...
Scherrer NM, Hopster K.To study the surgical, anesthetic and recovery qualities of horses receiving either a neuromuscular blocking agent (atracurium) or intravenous lidocaine (treatment groups A and L, respectively). Methods: A total of thirty horses presented for ocular surgery were used in this study. Methods: Horses were randomly assigned to receive either atracurium (group A) or a lidocaine constant rate infusion (group L). Surgical quality was graded on a scale from 1 (excellent)-5 (poor). While anesthetized, the heart rate, oxygen saturation and mean arterial blood pressure, and end-expiratory carbon dioxide ...
Stammwitz V, Honnens Ä, Hochhuth D, Schuberth HJ.Between 2015 and 2017, a marked increase of anaphylactic-like reactions after intravenous administration of gentamicin was observed first in horses and, later, also in humans. This worldwide issue led to safety measures including product recalls and safety warnings. Here, a German Marketing Authorization Holder (MAH) of an early and intensely affected veterinary product containing gentamicin describes the clinical approach of the company to analyze the root cause and identify the causative agent in the active pharmaceutical ingredient (API). The pharmacovigilance data of the MAH are presented,...
Calero Rodriguez A, de Grauw JC, van Loon JPAM.To determine the effect of fraction of inspired oxygen (FiO) on intrapulmonary shunt fraction as measured by F-shunt in ponies during isoflurane anaesthesia. Methods: Prospective, randomized clinical study. Methods: A group of 23 adult Shetland ponies undergoing a total of 32 anaesthetic procedures. Methods: Ponies were premedicated intravenously (IV) with detomidine (0.01 mg kg) and either morphine (0.1 mg kg) or butorphanol (0.02 mg kg). Anaesthesia was induced with ketamine (2.2 mg kg) and midazolam (0.07 mg kg) administered IV. Ponies were randomly allocated to maintenance of anaesthesia w...
Dias DCR, Ribeiro Filho JD, Viana RB, Bittencourt TCC, Dantas FTDR, Teixeira RBC, Di Filippo PA, Manso Filho HC, Alves SR, Santos PVM, Moreira NS.Continuous flow enteral fluid therapy with isotonic and hypotonic enteral electrolyte solutions are as safe and effective as intravenous fluid therapy. The aim of this study was to carry out a comparative assessment between continuous flow enteral and intravenous (IV) fluid therapy in adult experimentally dehydrated horses. Six experimentally dehydrated adult mares were used in a study carried out in a 6 × 3 crossover design, which each animal received three different treatments (isotonic enteral fluid therapy-EsISO, hypotonic enteral fluid therapy-EsHYPO and intravenous fluid therapy with La...
Aleman MR, True A, Scalco R, Crowe CM, Costa LRR, Chigerwe M.Irreversible sensorineural auditory loss has been reported in humans treated with aminoglycosides but not in horses. Objective: Investigate if auditory loss occurs in horses treated using the recommended IV daily dosage of gentamicin for 7 consecutive days. Methods: Ten healthy adult horses (7-15 years; females and males, 5 each). Methods: Prospective study. Physical and neurological examinations and renal function tests were performed. Gentamicin sulfate was administered at a dosage of 6.6 mg/kg via the jugular vein on alternating sides for 7 days. Gentamicin peak and trough concentratio...
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...
Bettschart-Wolfensberger R, Clarke KW, Vainio O, Aliabadi F, Demuth D.The pharmacokinetics of intravenous (i.v.) medetomidine (7 mcg kg(-1)) were best described by a two-compartment model in five ponies. Total body clearance was 4 (SD 0.60) 1 kg h,(-1)t(1/2alpha)7. 6 (0.91) minutes and t(1/2beta)51.3 (13.09) minutes. In one pony the one-compartmental model was best fit, and total body clearance was 4. 2 l kg h(-1)and t(1/2)was 11 minutes. Medetomidine plasma levels had fallen below the limits of quantification (0.05 ng ml(-1)) within 4 hours. Medetomidine 5 mcg kg(-1)i.v. followed by an infusion of 3.5 mcg kg h(-1)for two hours provided a constant level of sedat...
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...
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...
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...
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...
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)....
Bryant CE, England GC, Clarke KW.The sedative effects in horses of the new alpha 2 agonist medetomidine were compared with those of xylazine. Four ponies and one horse were treated on separate occasions with two doses of medetomidine (5 micrograms/kg bodyweight and 10 micrograms/kg bodyweight) and with one dose of xylazine (1 mg/kg bodyweight) given by intravenous injection. Medetomidine at 10 micrograms/kg was similar to 1 mg/kg xylazine in its sedative effect but produced more severe and more prolonged ataxia, and one animal fell over during the study. Medetomidine at 5 micrograms/kg produced less sedation but a similar deg...
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 ...
Bettschart-Wolfensberger R, Freeman SL, Bowen IM, Aliabadi FS, Weller R, Huhtinen M, Clarke KW.Currently available sedatives depress cardiopulmonary function considerably; therefore, it is important to search for new, less depressive sedatives. The study was performed to assess duration and intensity of cardiopulmonary side effects of a new sedative, dexmedetomidine (DEX), in horses. Objective: To study pharmacokinetics and cardiopulmonary effects of i.v. DEX. Methods: Pharmacokinetics of 3.5 microg/kg bwt i.v. DEX were studied in a group of 8 mature (mean age 4.4 years) and 6 old ponies (mean age 20 years). Cardiopulmonary data were recorded in mature ponies before and 5, 10, 20, 30, 4...
Jones PA, Tomasic M, Gentry PA.To evaluate the oncotic, hemodilutional, and hemostatic effects of IV infusions of a large volume of isotonic saline solution and 2 doses of 6% hydroxyethyl starch (HES) in clinically normal ponies. Methods: 12 adult ponies. Methods: Ponies were assigned to 3 treatment groups and received the following IV infusions: 80 ml of 0.9% sodium chloride/kg; 10 ml of 6% HES (in 0.9% sodium chloride)/kg; or 20 ml of 6% HES (in 0.9% sodium chloride)/kg. Blood samples were collected for determination of colloid oncotic pressure (COP), PCV, plasma total protein concentration, platelet count, von Willebrand...
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...
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...
Kaka JS, Klavano PA, Hayton WL.Ketamine HCl was administered IV to xylazine HCl-treated horses. The plasma concentration of ketamine was measured several times after administration of the drug and these data were used to develop a two-compartment pharmacokinetic model. The distribution and the elimination phase half-lives averaged 2.9 and 42 minutes. The volume of the central compartment averaged 212 ml/kg of body weight and the volume of the peripheral compartment was approximately threefold larger. The total body clearance of ketamine averaged 26.6 ml/minute/kg. Plasma protein binding of ketamine averaged 50% over the con...
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. The Part 2 of this review will focus in the use of opioids and α2 -agonists. Methods: Pubmed and Web of Science. Search terms: horse, inhalant anaesthesia, balanced anaesthesia, partial intravenous anaesthesia, opioids, morphine, pethidine, butorphanol, methadone, fentanyl, alfentanil, remifentanil, sufentanil, xylazine, romifidine, detomidine, medetomidine and dexmedetomidine. Conclusions: Different drugs and their combinations can be administered systemically...
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...
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...
Buhl R, Ersbøll AK, Larsen NH, Eriksen L, Koch J.To evaluate by echo- and electrocardiography the cardiac effects of sedation with detomidine hydrochloride, romifidine hydrochloride or acepromazine maleate in horses. Methods: An experimental study using a cross-over design without randomization. Methods: Eight clinically normal Standardbred trotters. Methods: Echocardiographic examinations (two-dimensional, guided M-mode and colour Doppler) were recorded on five different days. Heart rate (HR) and standard limb lead electrocardiograms were also obtained. Subsequently, horses were sedated with detomidine (0.01 mg kg(-1)), romifidine (0.04 mg ...
Purohit RC, Mysinger PW, Redding RW.A continuous series of electroencephalograms (EEG) was obtained from each of 6 mature horses which had been given xylazine and ketamine hydrochloride IV. Electrocardiograms and respiratory rates were also obtained. The EEG of the unsedated standing adult horse displayed a dominant fast activity in the range of 25-35 Hz, 5-30 microV superimposed over slower 1-4 Hz, 10-50 microV activity with occasional 10-14 Hz, 10-40 microV spindle-type activity. The xylazine-sedated horse displayed hypersynchronous EEG patterns, with the dominant activity being 1-3 Hz, 10-70 microV with overlying mixed freque...
Sanchez LC, Elfenbein JR, Robertson SA.To evaluate effects of butorphanol, acepromazine, and N-butylscopolammonium bromide (NBB) on visceral and somatic nociception and duodenal motility in conscious, healthy horses. Methods: 6 adult horses. Methods: Visceral nociception was evaluated by use of colorectal distention (CRD) and duodenal distention (DD) threshold. Somatic nociception was evaluated via thermal threshold (TT). Nose-to-ground height, heart rate, and respiratory rate were also measured. Each horse received each treatment in randomized order; investigators were not aware of treatments. Butorphanol was administered IV as a ...
Ensink JM, Klein WR, Mevius DJ, Klarenbeek A, Vulto AG.The pharmacokinetics of ampicillin and amoxicillin following intravenous administration at a dose rate of 15 and 10 mg/kg respectively were studied in four healthy adult horses. Pharmacokinetics of pivampicillin and amoxicillin were studied after oral administration to four healthy adult horses. Pivampicillin, a prodrug of ampicillin, was administered orally to starved and fed horses at a dose rate of 19.9 mg/kg, which is equivalent on a molecular basis to 15 mg/kg ampicillin. Amoxicillin was administered orally to starved horses only, at a dose rate of 20 mg/kg. Ampicillin and amoxicillin con...
Queiroz-Neto A, Zamur G, Gonçalves SC, Carregaro AB, Mataqueiro MI, Harkins JD, Tobin T.Amitraz, an acaricide used to control ectoparasites in animals has a complex pharmacological activity, including alpha2-adrenergic agonist action. The purpose of this research was to investigate the possible antinociceptive and/or sedative effect of amitraz in horses. The sedative effect of the intravenous (i.v.) injection of dimethylformamide (DMF, 5 mL, control) or amitraz (0.05, 0.10, 0.15 mg/kg), was investigated on the head ptosis test. The participation of alpha2-adrenergic receptors in the sedative effect provoked by amitraz was studied by dosing yohimbine (0.12 mg/kg, i.v.). To measure...
Smith GW, Constable PD, Foreman JH, Eppley RM, Waggoner AL, Tumbleson ME, Haschek WM.To determine whether cardiovascular dysfunction is evident in horses with leukoencephalomalacia experimentally induced by administration of fumonisin B1. Methods: 11 healthy horses of various breeds (body weight, 252 to 367 kg). Methods: Horses were randomly assigned to 3 groups and administered fumonisin B1 daily. Horses received IV injections of 0 (control horses; n = 4), 0.01 (3), or 0.20 mg (4) of fumonisin B1/kg for 7 to 28 days. Horses were examined daily for evidence of neurologic disease. When neurologic signs consistent with leukoencephalomalacia were evident, horses were anesthetized...
