References

Adami C, Westwood-Hearn H, Bolt DM, Monticelli P. Prevalence of electrolyte distur-bances and peri-anesthetic death risk factors in 120 horses undergoing colic surgery. J. Equine Vet. Sci.. 2020; 84 https://doi.org/10.1016/j.jevs.2019.102843

Adams HR. Adrenergic agonists and antagonists, 9th edn. In: Riviere JE, Papich MG (eds). Ames (IO): Wiley-Black-well; 2009

Aida H, Mizuno Y, Hobo S, Yoshida K, Fujinaga T. Cardiovascular and pulmonary effects of sevoflurane anesthesia in horses. Vet Surg. 1996; 25:164-170 https://doi.org/10.1111/j.1532-950x.1996.tb01393.x

Araos J, Kenny J.-E.-S, Rousseau-Blass F, Pang DSJ. Dynamic prediction of fluid responsiveness during positive pressure ventilation: a review of the physiology underlying heart–lung interactions and a critical interpretation. Vet Anaesth Analg. 2020; 47:(1)3-14 https://doi.org/10.1016/j.vaa.2019.08.004

Bettschart-Wolfensberger R, Kalchofner K, Neges K Total intravenous anaesthesia in horses using medetomidine and propofol. Vet Anaesth Analg. 2005; 32:(6)348-54 https://doi.org/10.1111/j.1467-2995.2005.00202.x

Blissit KJ, Raisis AL, Adams VJ, Rogers KH, Henley WE, Young LE. The effects of halothane and isoflurane on cardiovascular function in dorsally recumbent horses undergoing surgery. Vet Anaesth Analg. 2008; 35:208-219 https://doi.org/10.1111/j.1467-2995.2007.00376.x

Boesch JM. Anesthesia for the horse with colic. Vet Clin North Am Equine Pract. 2013; 29:(1)193-214 https://doi.org/10.1016/j.cveq.2012.11.005

Borde L, Amory H, Leroux AA Echocardiographic assessment of left ventricular systolic function in colic horses. J Equine Vet Sci.. 2011; 31:481-7 https://doi.org/10.1111%2Fjvim.14368

Corley KTT. Inotropes and vasopressors in adults and foals. Vet Clin North Am Eq Pract. 2004; 20:(1)77-106 https://doi.org/10.1016/j.cveq.2003.12.003

Corley KT. Shock, resuscitation, fluid and electrolyte therapy. In: Bernard W, Barr BS (eds). London (UK): Manson Publishing; 2012

Craig CA, Haskins SC, Hildebrand SV. The cardiopulmonary effects of dobutamine and norepinephrine in isoflurane-anesthetized foals. Vet Anaesth Analg. 2007; 34:(6)377-387 https://doi.org/10.1111/j.1467-2995.2006.00304.x

Dancker C, Hospter K, Rohn K, Kästner SB. Effects of dobutamine, dopamine, phenylephrine and noradrenaline on systemic haemodynamics and intestinal perfusion in isoflurane anaesthetised horses. Equine Vet J.. 2018; 50:(1)104-110 https://doi.org/10.1111/evj.12721

Daunt DA. Supportive therapy in the anesthetised horse. Vet Clin North Am Equine Pract. 1990; 6:(3)557-574 https://doi.org/10.1016/s0749-0739(17)30531-x

Dodman NH, Williams R, Court MH, Norman WM. Postanesthetic hind limb adductor myopathy in five horses. J Am Vet Med Assoc.. 1988; 193:83-86

Donaldson LL. Retrospective assessment of dobutamine therapy for hypotension in anaesthetized horses. Vet Surg. 1988; 17:(1)53-57 https://doi.org/10.1111/j.1532-950X.1988.tb00275.x

Driessen B. Intravenous lidocaine infusion in balanced anaesthesia for abdominal surgery: update and clinical experiences. Pferdeheilkunde. 2005; 21:133-141 https://doi.org/10.21836/PEM20050204

Duke T, Filzek U, Read MR, Read EK, Ferguson JG. Clinical observations surrounding an increased incidence of postanesthetic myopathy in halothane-anesthetized horses. Vet Anaesth Analg. 2006; 33:(2)122-127 https://doi.org/10.1111/j.1467-2995.2005.00189.x

Dugdale AHA, Langford J, Senior JM, Proudman CJ. The effect of inotropic and/or vasopressor support on postoperative survival following equine colic surgery. Vet Anaesth Analg. 2007; 34:(2)82-88 https://doi.org/10.1111/j.1467-2995.2006.00299.x

Dzikiti TB, Hellebrekers LJ, van Dijk P. Effects of intravenous lidocaine on isoflurane concentration, physiological parameters, metabolic parameters and stress-related hormones in horses undergoing surgery. J Vet Med A Physiol Pathol Clin Med. 2003; 50:(4)190-195 https://doi.org/10.1046/j.1439-0442.2003.00523.x

Edner A, Nyman G, Essén-Gustavsson B. The effects of spontaneous and mechanical ventilation on central cardiovascular function and peripheral perfusion during isoflurane anaesthesia in horses. Vet Anaesth Analg. 2005; 32:(3)136-146 https://doi.org/10.1111/j.1467-2995.2005.00190.x

Egger C, McCrackin MA, Hofmeister E Efficacy of preanesthetic intramuscular administration of ephedrine for prevention of anesthesia-induced hypotension in cats and dogs. Can Vet J.. 2009; 50:(2)179-184

Fantoni DT, Marchioni GG, Ida KK, Belo JNB, Zoppa ALV, Silva LCLC, Ambrósio AM. Effect of ephedrine and phenylephrine on cardiopulmonary parameters in horses undergoing elective surgery. Vet Anaesth Analg. 2013; 40:(4)367-374 https://doi.org/10.1111/vaa.12029

Gasthuys F, De Moor A, Parmentier D. Haemodynamic effects of change in position and respiratory mode during a standard halothane anaesthesia in ponies. J Vet Med. 1991; 10:203-11 https://doi.org/10.1111/j.1439-0442.1991.tb01003.x

Gozalo-Marcilla M, Gasthuys F, Schauvliege S. Partial intravenous anaesthesia in the horse: A review of intravenous agents used to supplement equine inhalation anaesthesia: Part 1: Lidocaine and ketamine. Vet Anaesth Analg. 2014; 41:(4)335-345 https://doi.org/10.1111/vaa.12179

Gozalo-Marcilla M, Gasthuys F, Schauvliege S. Partial intravenous anaesthesia in the horse: A review of intravenous agents used to supplement equine inhalation anaesthesia: Part 2: opioids and alpha-2 adrenoceptor agonists. Vet Anaesth Analg. 2015; 42:(1)1-16 https://doi.org/10.1111/vaa.12196

Grandy JL, Steffey EP, Hodgson DS, Woliner MJ. Arterial hypotension and the development of postanesthetic myopathy in halothane-anesthetized horses. Am J Vet. Res.. 1987; 48:192-197

Grosenbaugh DA, Muir WW. Cardiorespiratory effects of sevoflurane, isoflurane, and halothane anesthesia in horses. Am J Vet Res.. 1998; 59:101-106

Grubb TL, Benson GJ, Foreman JH Hemodynamic effects of ionized calcium in horses anesthetized with halothane or isoflurane. Am J Vet Res.. 1999; 6:1430-1435

Hardy J, Bednarski RM, Biller DS. Effect of phenylephrine on hemodynamics and splenic dimensions in horses. Am J Vet Res.. 1994; 55:(11)1570-8

J Hardy. Monitoring anaesthesia, 2nd edn. In: Muir WW, Hubbell JA (eds). St Louis (MO): Saunders Elsevier; 2009

Hector RC, Rezende ML, Mama KR, Hess AM. Recovery quality following a single post-anaesthetic dose of dexmedetomidine or romifidine in sevoflurane anaesthetised horses. Equine Vet J.. 2020; 52:(5)685-91 https://doi.org/10.1111/evj.13238

Hellyer PW, Wagner AE, Mama KR., Gaynor JS. The effects of dobutamine and ephedrine on packed cell volume, total protein, heart rate, and blood pressure in anaesthetized horses. J Vet Pharmacol Ther.. 1998; 21:(6)497-499 https://doi.org/10.1046/j.1365-2885.1998.00170.x

Henninger DD, Snyder JR, Pascoe JR Microvascular permeability changes in ischemia/reperfusion injury in the ascending colon of horses. J Am Vet Med Assoc. 1992; 201:(8)1191-6

Kalchofner KS, Picek S, Ringer SK, Jackson M, Hässig M, Bettschart-Wolfensberger R. A study of cardiovascular function under controlled and spontaneous ventilation in isoflurane-medetomidine anaesthetized horses. Vet Anaesth Analg. 2009; 36:(5)426-435 https://doi.org/10.1111/j.1467-2995.2009.00477.x

Lee YH, Clarke KW, Alibhai HI Effects of dopamine, dobutamine, dopexamine, phenylephrine, and saline solution on intramuscular blood flow and other cardiopulmonary variables in halothane-anesthetized ponies. Am J Vet Res.. 1998; 59:1463-1472

Lee YHL, Clarke K, Alibhai HI The effects of ephedrine on intramuscular blood flow and other cardiopulmonary parameters in halothane-anesthetized ponies. Vet Anaesth Analg. 2002; 29:171-181 https://doi.org/10.1046/j.1467-2995.2002.00095.x

Lindsay WA, Robinson GM, Brunson DB, Majors LJ. Induction of equine postanesthetic myositis after halothane induced hypotension. Am J Vet Res.. 1989; 50:404-410

Mama KR, Wagner AE, Steffey EP, et al. Evaluation of xylazine and ketamine for total intravenous anesthesia in horses. Am J Vet Res. 2005; 66:1002-7

McKelvey D, Hollingshead W. The preanesthetic period, 3rd edn. In: McKelvey D, Hollingshead W (eds). : St. Louis (MO); 2003

Merlo M, Rota M. Manual of Small Animal Anesthesia, 2nd edn. WB Saunders: Philadelphia (PA); 1999

Monteiro ER, Teixeira Neto FJ, Castro VB, Campagnol D. Effects of acepromazine on the cardiovascular actions of dopamine in anesthetized dogs. Vet Anaesth Analg. 2007; (5)312-321 https://doi.org/10.1111/j.1467-2995.2006.00328.x

Moreno-Martinez F, Mosing M, Senior M. Controlled mechanical ventilation in equine anaesthesia: Physiological background and basic considerations (Part 1). In Equine Veterinary Education. 2022; 34:(6)320-329 https://doi.org/10.1111/eve.13476

Monteiro ER, de Souza JFF, Baiotto GC Influence of acepromazine on the cardiovascular actions of dobutamine in isoflurane-anesthetized horses. Cienc Rural. 2011; 41:470-475

Muir WW, Mason DE. Effect of diazepam, acepromazine, detomidine, and xylazine on thiamylal anesthesia in horses. J Am Vet Med Assoc.. 1993; 203:1031-1037

Midon M, Ido C, Silva H, Horr M, Escobar A. Effects of acepromazine premedication on arterial oxygenation and cardiovascular variables in isoflurane-anesthetized horses in dorsal recumbency. Vet Anaesth Analg. 2021; 48:(6) https://doi.org/10.1016/j.vaa.2021.08.033

Mizuno Y, Aida H, Hara H, Fujinaga T. Cardiovascular effects of intermittent positive pressure ventilation in the anaesthetized horse. J Vet Med Sci.. 1994; 56:39-44 https://doi.org/10.1292/jvms.56.39

Morgan BC, Martin WE, Hornbein TF Hemodynamic effects of intermittent positive pressure respiration. Anesthesiology. 1996; 27:584-590

Muir WW, McGuirk SM. Pharmacology and pharmacokinetics of drugs used to treat cardiac disease in horses. Vet Clin North Am.. 1985; 1:(2)335-42 https://doi.org/10.1016/s0749-0739(17)30759-9

Noel-Morgan J, Muir WW. Anesthesia-associated relative hypovolemia: mechanisms, monitoring, and treatment considerations. Front Vet Sci.. 2018; 5 https://doi.org/10.3389/fvets.2018.00053

Oh SY, Hwang S, Seo HS, Lee S, Kim H-Y. Bezold-Jarisch reflex induced by dopamine during isoflurane anesthesia in small Dogs. Acta Scientiae Veterinariae. 2022; 50:(1)

Ohta M, Kurimoto S, Ishikawa Y, Tokushige H, Mae N, Nagata SI, Mamada M. Cardiovascular effects of dobutamine and phenylephrine infusion in sevoflurane anesthetized thoroughbred horses. J Vet Med Sci.. 2013; 75:(11)1443-1448 https://doi.org/10.1292/jvms.13-0104

Ohta M, Oku K, Yamanaka T, Mizuno Y. Anesthetic management with sevoflurane and oxygen for orthopedic surgeries in racehorses. J Vet Med Sci.. 2000; 62:1017-1020 https://doi.org/10.1292/jvms.62.1017

Parry BW, Anderson GA, Gay CC. Prognosis in equine colic: A study of individual variables used in case assessment. Equine Vet J.. 1983; 15 https://doi.org/10.1111/j.2042-3306.1983.tb01818.x

Parviainen AKJ, Trim CM. Complications associated with anaesthesia for ocular surgery: a retrospective study 1989–1996. Equine Vet J.. 2000; 32:555-559 https://doi.org/10.2746/042516400777584659

Pöppel N, Hopster K, Geburek F, Kästner S. Influence of ketamine or xylazine supplementation on isoflurane anaesthetized horses - A controlled clinical trial. Vet Anaesth Analg. 2015; 42:(1)30-38 https://doi.org/10.1111/vaa.12176

Radcliffe RM, Divers TJ, Fletcher DJ, et al. Evaluation of L-lactate and cardiac troponin I in horses undergoing emergency abdominal surgery. J Vet Emerg Crit Care. 2012; 22:313-9

Raisis AL, Young LE, Blissitt KJ, Walsh K, Meire HB, Taylor PM, Lekeux P. Effect of a 30-minute infusion of dobutamine hydrochloride on hind limb blood flow and hemodynamics in halothane anaesthetised horses. Am J Vet Res.. 2000; 61:1282-1288 https://doi.org/10.2460/ajvr.2000.61.1282

Raisis AL, Young LE, Meire HB Measurements of hind limb blood flow recorded using Doppler ultrasound during administration of vasoactive agents in halothane-anesthetized horses. Vet Radiol Ultrasound. 2000a; 41:64-72 https://doi.org/10.1111/j.1740-8261.2000.tb00429.x

Richey MT, Holland MS, McGrath CJ, Dodman NH, Marshall DB, Court MH, Norman WM, Seeler DC. Equine post-anesthetic lameness. A retrospective study. Vet Surg. 1990; 19:392-397 https://doi.org/10.1111/j.1532-950x.1990.tb01216.x

Robertson SA. Cardiovascular emergencies associated with anaesthesia. In: Marr C (ed). London: WB Saunders; 1999

Roos A, Thomas LJ, Nagel EL, Prommas DC. Pulmonary vascular resistance as determined by lung inflation and vascular pressures. J Appl Physiol.. 1961; 16:77-84 https://doi.org/10.1152/jappl.1961.16.1.77

Rose RJ. A physiological approach to fluid and electrolyte therapy in the horse. Equine Vet J.. 1981; 13:(1)7-14 https://doi.org/10.1111/j.2042-3306.1981.tb03439.x

Schauvliege S, Gasthuys F. Drugs for cardiovascular support in anesthetized horses. Vet Clin North Am Equine Pract. 2013; 1:19-49 https://doi.org/10.1016/j.cveq.2012.11.011

Schier MF, Raisis AL, Secombe CJ, Hosgood G, Musk GC, Lester GD. Effects of dobutamine hydrochloride on cardiovascular function in horses anesthetized with isoflurane with or without acepromazine maleate premedication. Am J Vet Res.. 2016; 77:1318-1324 https://doi.org/10.2460/ajvr.77.12.1318

Steffey EP, Howland D Comparison of circulatory and respiratory effects of isoflurane and halothane anesthesia in horses. Am J Vet Res.. 1980; 41:821-825

Steffey EP. Mechanical ventilation of the anesthetized horse. Vet Clin North Am: Large Anim Pract. 198 3:97-110 https://doi.org/10.1016/S0196-9846%2817%2930148-9

Swanson CR, Muir WW, Bednarski RM, Skarda RT, Hubbell JAE. Hemodynamic responses in halothane-anaesthetized horses given infusions of dopamine or dobutamine. Am J Vet Res.. 1985; 46:365-71

Tranquilli WJ, Thurmon JC, Grimm KA. Lumb and Jones' Veterinary Anesthesia and Analgesia, 4th edn. Ames (IW): Blackwell Press; 2007

Trim CM, Moore JN, White NA. Cardiopulmonary effects of dopamine hydrochloride in anaesthetised horses. Equine Vet J.. 1985; 17:41-44 https://doi.org/10.1111/j.2042-3306.1985.tb02038.x

Trim CM, Moore JN, Clark ES. Renal effects of dopamine infusion in conscious horses. Equine Vet J.. 1989; 21:124-128 https://doi.org/10.1111/j.2042-3306.1989.tb05671.x

Valverde A, Giguère S, Sanchez LC, Shih A, Ryan C. Effects of dobutamine, norepinephrine, and vasopressin on cardiovascular function in anesthetized neonatal foals with induced hypotension. Am J Vet Res.. 2006; 67:(10)1730-1737 https://doi.org/10.2460/ajvr.67.10.1730

Vitale V, Sgorbini M, Briganti A, Corazza M, Breghi G, Staffieri F. Evaluation of echocardiographic parameters during increasing infusion rates of dobutamine in isoflurane-anesthetized horses. J Equine Vet Sci.. 2013; 33:(12)1110-1114 https://doi.org/10.1016/j.jevs.2013.04.012

Voulgaris DA, Hofmeister EH. Multivariate analysis of factors associated with post-anesthetic times to standing in isoflurane-anesthetized horses: 381 cases. Vet Anaesth Analg. 2009; 36:(5)414-420 https://doi.org/10.1111/j.1467-2995.2009.00472.x

Wagner AE, Bednarski RM, Muir WW Hemodynamic effects of carbon dioxide during intermittent positive-pressure ventilation in horses. Am J Vet Res.. 1990; 51:1922-1929

Wagner AE. Complications in equine anesthesia. Vet Clin Equine. 2009; 24:735-752 https://doi.org/10.1016/j.cveq.2008.10.002

Weaver BM, Walley RV. Ventilation and cardiovascular studies during mechanical control of ventilation in horses. Equine Vet J.. 1975; 7:9-15 https://doi.org/10.1111/j.2042-3306.1975.tb03222.x

Young SS, Taylor PM. Factors influencing the outcome of equine anaesthesia: a review of 1,314 cases. Equine Vet. J.. 1993; 25:147-151 https://doi.org/10.1111/j.2042-3306.1993.tb02926.x

Young LE, Blissitt KJ, Clutton RE, Molony V. Temporal effects of an infusion of dobutamine hydrochloride in horses anesthetised with halothane. Am J Vet Res.. 1998; 59:1027-1032

Veterinary
Anaesthesiology
Surgical

Intra-operative hypotension in anaesthetised horses

02 May 2023
Clinical
19 mins read
02 May 2023
Volume 7 · Issue 3

Abstract

The prompt and effective treatment of hypotension is important in order to avoid its negative consequences, but the management of hypotension may not always be straight forward. Treatment options may include reducing delivered volatile agent concentration, optimising circulating volume and administering positive inotropes or vasopressor agents. In order to approach treatment in the most effective way, it is important to address the underlying cause of or the most significant factor which may be contributing to suboptimal arterial blood pressure. This article summarises the causes of hypotension and various approaches to management and treatment.

Hypotension is a relatively common complication during inhalational agent anaesthesia in horses, with a reported prevalence of 42% and 88% in horses undergoing anaesthesia for elective and abdominal surgery, respectively (Parviainen and Trim, 2000; Adami et al, 2020). Horses may be particularly susceptible to the negative inotropic and vasodilatory effects of inhalational agents (Grosenbaugh and Muir, 1998), which is reflected by the much lower tendency for hypotension to occur during total intravenous anaesthesia (Bettschart-Wolfensberger et al, 2005; Mama et al, 2005).

Hypotension has been defined as a mean arterial pressure (MAP) <70 mmHg (Voulgaris and Hofmeister, 2009) and most anaesthetists aim to maintain a MAP ≥70 mmHg in anaesthetised horses (Wagner, 2009). Intra-operative hypotension has been associated with prolonged time to standing (Voulgaris and Hofmeister, 2009), poorer recovery quality (Hector et al, 2020), poor survival in horses with acute abdominal disease (Parry et al, 1983) and increased incidence or severity of myopathy (Grandy et al, 1987; Dodman et al, 1988; Lindsay et al, 1989; Richey et al. 1990; Young and Taylor 1993; Duke et al, 2006).

Register now to continue reading

Thank you for visiting UK-VET Equine and reading some of our peer-reviewed content for veterinary professionals. To continue reading this article, please register today.

Register
Or continue by

Signing in with your registered email address

equine anaesthesia
hypotension
arterial blood pressure
vasoactive drugs