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Schüttler D, Tomsits P, Bleyer C, Vlcek J, Pauly V, Hesse N, Sinner M, Merkus D, Hamers J, Kääb S, Clauss S. A practical guide to setting up pig models for cardiovascular catheterization, electrophysiological assessment and heart disease research. Lab Anim (NY) 2022; 51:46-67. [PMID: 35087256 DOI: 10.1038/s41684-021-00909-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 12/15/2021] [Indexed: 01/09/2023]
Abstract
Over the past years, the use of large animals has become increasingly interesting in translational research, to bridge the gap between basic research in rodents and targeted therapies in humans. Pigs are highly valued in cardiovascular research because of their anatomical, hemodynamic and electrophysiological features, which closely resemble those of humans. For studying these aspects in swine, cardiac catheterization techniques are essential procedures. Although cardiac catheterization seems to be comparatively easy in pigs as human equipment can be used to perform the procedure, there are some pitfalls. Here we provide a detailed protocol to guide the reader through different aspects of cardiac catheterization in pigs. We suggest an approach for safe intubation and extubation, provide tips for perioperative and postoperative management of the animals and guide the reader through different experimental steps, including sheath insertion. We also describe the procedures for basic electrophysiological assessment of conduction properties and atrial fibrillation induction, hemodynamic assessment via pressure-volume loops, right heart and left heart catheterization and the development of a myocardial infarction model by balloon occlusion. This protocol was developed in Landrace pigs and can be adapted to other pig breeds or other large animal species. This protocol requires approximately six and a half working hours in total and should be performed by researchers with previous experience in large animal experimentation and in the presence of a veterinarian.
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Affiliation(s)
- Dominik Schüttler
- Medizinische Klinik und Poliklinik I, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Munich, Munich Heart Alliance (MHA), Munich, Germany.,Institute of Surgical Research at the Walter-Brendel-Centre of Experimental Medicine, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany
| | - Philipp Tomsits
- Medizinische Klinik und Poliklinik I, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Munich, Munich Heart Alliance (MHA), Munich, Germany.,Institute of Surgical Research at the Walter-Brendel-Centre of Experimental Medicine, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany
| | - Christina Bleyer
- Medizinische Klinik und Poliklinik I, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Munich, Munich Heart Alliance (MHA), Munich, Germany.,Institute of Surgical Research at the Walter-Brendel-Centre of Experimental Medicine, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany
| | - Julia Vlcek
- Medizinische Klinik und Poliklinik I, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany.,Institute of Surgical Research at the Walter-Brendel-Centre of Experimental Medicine, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany
| | - Valerie Pauly
- Medizinische Klinik und Poliklinik I, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Munich, Munich Heart Alliance (MHA), Munich, Germany.,Institute of Surgical Research at the Walter-Brendel-Centre of Experimental Medicine, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany
| | - Nora Hesse
- Medizinische Klinik und Poliklinik I, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Munich, Munich Heart Alliance (MHA), Munich, Germany.,Institute of Surgical Research at the Walter-Brendel-Centre of Experimental Medicine, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany
| | - Moritz Sinner
- Medizinische Klinik und Poliklinik I, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Munich, Munich Heart Alliance (MHA), Munich, Germany
| | - Daphne Merkus
- DZHK (German Centre for Cardiovascular Research), Partner Site Munich, Munich Heart Alliance (MHA), Munich, Germany.,Institute of Surgical Research at the Walter-Brendel-Centre of Experimental Medicine, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany.,Division of Experimental Cardiology, Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Jules Hamers
- DZHK (German Centre for Cardiovascular Research), Partner Site Munich, Munich Heart Alliance (MHA), Munich, Germany.,Institute of Surgical Research at the Walter-Brendel-Centre of Experimental Medicine, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany
| | - Stefan Kääb
- Medizinische Klinik und Poliklinik I, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany.,DZHK (German Centre for Cardiovascular Research), Partner Site Munich, Munich Heart Alliance (MHA), Munich, Germany
| | - Sebastian Clauss
- Medizinische Klinik und Poliklinik I, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany. .,DZHK (German Centre for Cardiovascular Research), Partner Site Munich, Munich Heart Alliance (MHA), Munich, Germany. .,Institute of Surgical Research at the Walter-Brendel-Centre of Experimental Medicine, LMU Hospital, Ludwig-Maximilians-Universität Munich (LMU), Munich, Germany.
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Recovery after General Anaesthesia in Adult Horses: A Structured Summary of the Literature. Animals (Basel) 2021; 11:ani11061777. [PMID: 34198637 PMCID: PMC8232193 DOI: 10.3390/ani11061777] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 06/03/2021] [Accepted: 06/08/2021] [Indexed: 12/26/2022] Open
Abstract
Simple Summary Recovery is the most dangerous phase of general anaesthesia in horses. Numerous publications have reported about this phase, but structured reviews that try to reduce the risk of bias of narrative reviews/expert opinions, focussing on the topic are missing. Therefore, the aim of the present article was to publish the first structured review as a summary of the literature focussing on the recovery phase after general anaesthesia in horses. The objective was to summarise the available literature, taking into account the scientific evidence of the individual studies. A structured approach was followed with two experts in the field independently deciding on article inclusion and its level of scientific evidence. A total number of 444 articles, sorted by topics and classified based on their levels of evidence, were finally included into the present summary. The most important findings were summarised and discussed. The present structured review can be used as a compilation of the publications that, to date, focus on the recovery phase after general anaesthesia in adult horses. This type of review tries to minimise the risk of bias inherent to narrative reviews/expert opinions. Abstract Recovery remains the most dangerous phase of general anaesthesia in horses. The objective of this publication was to perform a structured literature review including levels of evidence (LoE) of each study with the keywords “recovery anaesthesia horse”, entered at once, in the search browsers PubMed and Web of Science. The two authors independently evaluated each candidate article. A final list with 444 articles was obtained on 5 April 2021, classified as: 41 “narrative reviews/expert opinions”, 16 “retrospective outcome studies”, 5 “surveys”, 59 “premedication/sedation and induction drugs”, 27 “maintenance with inhalant agents”, 55 “maintenance with total intravenous anaesthesia (TIVA)”, 3 “TIVA versus inhalants”, 56 “maintenance with partial intravenous anaesthesia (PIVA)”, 27 “other drugs used during maintenance”, 18 “drugs before/during recovery”, 18 “recovery systems”, 21 “respiratory system in recovery”, 41 “other factors”, 51 “case series/reports” and 6 “systems to score recoveries”. Of them, 167 were LoE 1, 36 LoE 2, 33 LoE 3, 110 LoE 4, 90 LoE 5 and 8 could not be classified based on the available abstract. This review can be used as an up-to-date compilation of the literature about recovery after general anaesthesia in adult horses that tried to minimise the bias inherent to narrative reviews.
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Chaves RHDF, Souza NFD, Imbeloni AA, Neves ACDS, Teixeira RKC, Santos CDCD. Evaluation of blood pressure in feline night monkeys (Aotus azarae infulatus
) under different restraint protocols. J Med Primatol 2015. [DOI: 10.1111/jmp.12183] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
| | - Nazaré Fonseca de Souza
- Universidade Federal Rural da Amazônia (UFRA); Instituto da Saúde e Produção Animal (ISPA); Pará Brazil
| | - Aline Amaral Imbeloni
- Centro Nacional de Primatas (CENP); Secretaria de Vigilância em Saúde (SVS); Ministério da Saúde(MS); Ananindeua Pará Brazil
| | | | - Renan Kleber Costa Teixeira
- Universidade do Estado do Pará (UEPA); Centro de Ciências Biológicas e da Saúde (CCBS) Laboratório de Cirurgia Experimental (LCE); Belém Pará Brazil
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4
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Trefz P, Schmidt M, Oertel P, Obermeier J, Brock B, Kamysek S, Dunkl J, Zimmermann R, Schubert JK, Miekisch W. Continuous Real Time Breath Gas Monitoring in the Clinical Environment by Proton-Transfer-Reaction-Time-of-Flight-Mass Spectrometry. Anal Chem 2013; 85:10321-9. [DOI: 10.1021/ac402298v] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Phillip Trefz
- Department of Anaesthesia
and Intensive Care, University Medical Center Rostock, Schillingallee 35, 18057 Rostock, Germany
| | - Markus Schmidt
- Department of Anaesthesia
and Intensive Care, University Medical Center Rostock, Schillingallee 35, 18057 Rostock, Germany
| | - Peter Oertel
- Department of Anaesthesia
and Intensive Care, University Medical Center Rostock, Schillingallee 35, 18057 Rostock, Germany
| | - Juliane Obermeier
- Department of Anaesthesia
and Intensive Care, University Medical Center Rostock, Schillingallee 35, 18057 Rostock, Germany
| | - Beate Brock
- Department of Anaesthesia
and Intensive Care, University Medical Center Rostock, Schillingallee 35, 18057 Rostock, Germany
| | - Svend Kamysek
- Department of Anaesthesia
and Intensive Care, University Medical Center Rostock, Schillingallee 35, 18057 Rostock, Germany
| | - Jürgen Dunkl
- Ionicon Analytik GmbH, Eduard-Bodem-Gasse 3, A-6020 Innsbruck, Austria
| | - Ralf Zimmermann
- Joint Mass Spectrometry
Centre, Chair of Analytical Chemistry, University of Rostock, Dr. Lorenz Weg
1, 18059 Rostock, Germany and Joint Mass Spectrometry Centre, Cooperation Group “Comprehensive
Molecular Analytics”, Helmholtz Zentrum München, D-85764 Neuherberg, Germany
| | - Jochen K. Schubert
- Department of Anaesthesia
and Intensive Care, University Medical Center Rostock, Schillingallee 35, 18057 Rostock, Germany
| | - Wolfram Miekisch
- Department of Anaesthesia
and Intensive Care, University Medical Center Rostock, Schillingallee 35, 18057 Rostock, Germany
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Reese SL, Zekas LJ, Iazbik MC, Lehman A, Couto CG. EFFECT OF SEVOFLURANE ANESTHESIA AND BLOOD DONATION ON THE SONOGRAPHIC APPEARANCE OF THE SPLEEN IN 60 HEALTHY CATS. Vet Radiol Ultrasound 2012; 54:168-75. [DOI: 10.1111/j.1740-8261.2012.01990.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Accepted: 08/24/2012] [Indexed: 12/01/2022] Open
Affiliation(s)
| | - Lisa J. Zekas
- Veterinary Clinical Sciences; The Ohio State University
| | | | - Amy Lehman
- Center for Biostatistics; The Ohio State University
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6
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Granone TD, de Francisco ON, Killos MB, Quandt JE, Mandsager RE, Graham LF. Comparison of three different inhalant anesthetic agents (isoflurane, sevoflurane, desflurane) in red-tailed hawks (Buteo jamaicensis). Vet Anaesth Analg 2012; 39:29-37. [DOI: 10.1111/j.1467-2995.2011.00668.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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7
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Nunes N, Leite A, Paula D, Nishimori C, Souza A, Santos P, Guerrero PH, Lopes P. Intracranial variables in propofol or sevoflurane-anesthestized dogs subjected to subarachnoid administration of iohexol. ARQ BRAS MED VET ZOO 2011. [DOI: 10.1590/s0102-09352011000600006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The effects of subarachnoid administration of iohexol on intracranial hemodynamic in dogs anesthetized with propofol or sevoflurane were evaluated. Thirty adult animals (10.9±2.9kg) were distributed into two groups: PG, where propofol was used for induction (10±0.5mg/kg), followed by a continuous rate infusion at 0.55±0.15mg/kg/hour, and SG, where sevoflurane was administered for induction (2.5 MAC) and for anesthetic maintenance (1.5 MAC). A fiberoptic catheter was implanted on the right superficial cerebral cortex to monitor intracranial pressure (ICP). After 30 minutes, cerebrospinal fluid (CSF) was collected at the cisterna magna and iohexol was injected. The measurements were performed before CSF collection (TA), after the iohexol injection (T0), and at 10-minute intervals (T10 to T60). Intracranial pressure decreased at T0 in SG. Cerebral perfusion pressure at T0 was higher than at TA, T50 and T60 in PG, but in SG, the mean value at T0 was higher than the ones from T20 to T60. Mean arterial pressure at T0 was higher than at TA in PG, while in SG, the values from T20 to T60 were lower than at T0. The heart rate at T60 was lower than at T0 in PG. Cardiac output at TA was lower than at T60 in SG. The cerebrospinal fluid collection and administration of iohexol promoted decrease in intracranial pressure in sevolflurane-anesthetized dogs and increase in cerebral perfusion pressure in propofol-anesthetized dogs.
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8
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Varela Lopez O, Alvarez Vazquez JC, Gonzalez Cantalapiedra A, Rosolen SG. Effects of hypercapnia on the electroretinogram in sevoflurane and isoflurane anaesthetized dogs. Doc Ophthalmol 2010; 121:9-20. [DOI: 10.1007/s10633-010-9223-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2009] [Accepted: 02/01/2010] [Indexed: 10/19/2022]
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9
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Lozano AJ, Brodbelt DC, Borer KE, Armitage-Chan E, Clarke KW, Alibhai HIK. A comparison of the duration and quality of recovery from isoflurane, sevoflurane and desflurane anaesthesia in dogs undergoing magnetic resonance imaging. Vet Anaesth Analg 2009; 36:220-9. [PMID: 19397773 DOI: 10.1111/j.1467-2995.2009.00451.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To compare the recovery after anaesthesia with isoflurane, sevoflurane and desflurane in dogs undergoing magnetic resonance imaging (MRI) of the brain. STUDY DESIGN Prospective, randomized clinical trial. ANIMALS Thirty-eight dogs weighing 23.7 +/- 12.6 kg. METHODS Following pre-medication with meperidine, 3 mg kg(-1) administered intramuscularly, anaesthesia was induced intravenously with propofol (mean dose 4.26 +/- 1.3 mg kg(-1)), the trachea was intubated, and an inhalational anaesthetic agent was administered in oxygen. The dogs were randomly allocated to one of three groups: group I (n = 13) received isoflurane, group S (n = 12) received sevoflurane and group D (n = 13) received desflurane. Parameters recorded included cardiopulmonary data, body temperature, end-tidal anaesthetic concentration, duration of anaesthesia, and recovery times and quality. Qualitative data were compared using chi-squared and Fisher's exact tests and quantitative data with anova and Kruskal-Wallis test. Post-hoc comparisons for quantitative data were undertaken with the Mann-Whitney U-test. RESULTS The duration of anaesthesia [mean and standard deviation (SD)] in group I was: 105.3 (27.48) minutes, group S: 120.67 (19.4) minutes, and group D: 113.69 (26.68) minutes (p = 0.32). Times to extubation [group I: 8 minutes, (interquartile range 6-9.5), group S: 7 minutes (IQR 5-7), group D: 5 minutes (IQR 3.5-7), p = 0.017] and to sternal recumbency [group I: 11 minutes (IQR 9.5-13.5), group S: 9.5 minutes (IQR 7.25-11.75), group D: 7 minutes (range 3.5-11.5), p = 0.048] were significantly different, as were times to standing. One dog, following sevoflurane, had an unacceptable quality of recovery, but most other recoveries were calm, with no significant difference between groups. CONCLUSIONS AND CLINICAL RELEVANCE All three agents appeared suitable for use. Dogs' tracheas were extubated and the dogs recovered to sternal recumbency most rapidly after desflurane. This may be advantageous for animals with some neurological diseases and for day case procedures.
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Morgaz J, Granados M, Domínguez J, Navarrete R, Galán A, Fernández J, Gómez-Villamandos R. Relationship of bispectral index to hemodynamic variables and alveolar concentration multiples of sevoflurane in puppies. Res Vet Sci 2009; 86:508-13. [DOI: 10.1016/j.rvsc.2008.09.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2008] [Revised: 08/05/2008] [Accepted: 09/15/2008] [Indexed: 10/21/2022]
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11
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Mohamadnia AR, Hughes G, Clarke KW. Maintenance of anaesthesia in sheep with isoflurane, desflurane or sevoflurane. Vet Rec 2008; 163:210-5. [DOI: 10.1136/vr.163.7.210] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- A. R. Mohamadnia
- Department of Clinical Sciences; College of Veterinary Medicine, 2 Saman Road; University of Shahrekord; Shahrekord 88186/34141 Iran
| | - G. Hughes
- Royal Veterinary College; Hawkshead Lane Hatfield Hertfordshire AL9 7TA
| | - K. W. Clarke
- Royal Veterinary College; Hawkshead Lane Hatfield Hertfordshire AL9 7TA
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Moeser AJ, Blikslager AT, Swanson C. Determination of minimum alveolar concentration of sevoflurane in juvenile swine. Res Vet Sci 2008; 84:283-5. [PMID: 17570452 DOI: 10.1016/j.rvsc.2007.03.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2006] [Revised: 02/23/2007] [Accepted: 03/31/2007] [Indexed: 11/15/2022]
Abstract
Pigs are important animal models in veterinary and medical research and have been widely used in experiments requiring surgical anesthesia. Sevoflurane is an inhalant anesthetic with unique properties that make it an ideal anesthetic for mask induction and anesthesia maintenance. However, there are relatively few studies reporting the anesthetic requirements for sevoflurane in juvenile swine, an age group that is commonly used in research experiments. Therefore the objective of this study was to determine the Minimum Alveolar Concentration (MAC) for sevoflurane in juvenile swine. Sevoflurane anesthesia was induced in six Yorkshire-cross pigs of approximately 9 weeks-of-age and MAC for sevoflurane was determined. The sevoflurane MAC value was determined to be 3.5+/-0.1% which is notably higher than values reported in the literature for pigs. This discrepancy in MAC values may represent changes in anesthetic requirements between different age groups of pigs and differences in the type of stimulus used to determine MAC.
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Affiliation(s)
- Adam J Moeser
- Department of Clinical Sciences and Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA.
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Gómez-Villamandos RJ, Palacios C, Benítez A, Granados MM, Domínguez JM, Estepa JC, Ruiz I, Aguilera E, Santisteban JM. Effect of medetomidine infusion on the anaesthetic requirements of desflurane in dogs. Res Vet Sci 2008; 84:68-73. [PMID: 17408710 DOI: 10.1016/j.rvsc.2007.02.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Revised: 02/08/2007] [Accepted: 02/12/2007] [Indexed: 11/30/2022]
Abstract
The objective of this paper was to evaluate the effect of constant rate infusion of medetomidine on the anaesthetic requirements of desflurane in dogs. For this, six healthy dogs were studied. Measurements for baseline were taken in the awake, unsedated dogs, then each dog received intravenously (i.v.) three anaesthetic protocols: M (no medetomidine infusion), M0.5 (infusion of medetomidine at 0.5 microg/kg/h, i.v.) or M1 (infusion of medetomidine at 1 microg/kg/h, i.v.). All dogs were sedated with medetomidine (2 microg/kg, i.v.) and measurements repeated in 10 min. Induction of anaesthesia was delivered with propofol (3 mg/kg, i.v.) and maintained with desflurane for 90 min to achieve a defined surgical plane of anaesthesia in all cases. After tracheal intubation infusion of medetomidine was initiated and maintained until the end of anaesthesia. Cardiovascular, respiratory, arterial pH (pHa) and arterial blood gas tensions (PaO(2), PaCO(2)) variables were measured during the procedure. End tidal desflurane concentration (EtDES) was recorded throughout anaesthesia. Time to extubation, time to sternal recumbency and time to standing were also noted. Heart rate and respiratory rate were significantly decreased during sedation in all protocols compared to baseline values. Mean heart rate, mean arterial pressure, systolic arterial pressure, diastolic arterial pressure, respiratory rate, tidal volume, arterial oxygen saturation, end-tidal CO(2), pHa, PaO(2), and PaCO(2) during anaesthesia were similar for all protocols. EtDES for M (8.6 +/- 0.8%) was statistically higher than for M0.5 (7.6 +/- 0.5%) and M1 (7.3 +/- 0.7%) protocols. Infusion of medetomidine reduces desflurane concentration required to maintain anaesthesia in dogs.
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Affiliation(s)
- R J Gómez-Villamandos
- Department of Animal Medicine and Surgery, Faculty of Veterinary Medicine, University of Córdoba, Campus Universitario de Rabanales, 14014 Córdoba, Spain.
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Iazbik MC, Ochoa PG, Westendorf N, Charske J, Couto C. Effects of Blood Collection for Transfusion on Arterial Blood Pressure, Heart Rate, and PCV in Cats. J Vet Intern Med 2007. [DOI: 10.1111/j.1939-1676.2007.tb01935.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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15
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Kästner SB, Boller J, Kutter AP, Pakarinen SM, Ramela MP, Huhtinen MK. Comparison of cardiopulmonary effects of dexmedetomidine administered as a constant rate infusion without loading dose in sheep and goats anaesthetised with sevoflurane. Small Rumin Res 2007. [DOI: 10.1016/j.smallrumres.2006.05.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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16
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Grubb TL, Schlipf JW, Riebold TW, Cebra CK, Poland L, Zawadzkas X, Mailhot N. Minimum alveolar concentration of desflurane in llamas and alpacas. Vet Anaesth Analg 2006; 33:351-5. [PMID: 17083607 DOI: 10.1111/j.1467-2995.2005.00278.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To determine the minimum alveolar concentration (MAC) of desflurane in llamas and alpacas. DESIGN Prospective study. Animals Six healthy adult llamas and six healthy adult alpacas. PROCEDURE Anesthesia was induced with desflurane delivered with oxygen through a mask. An endotracheal tube was inserted, and a port for continuous measurement of end-tidal and inspired desflurane concentrations was placed between the endotracheal tube and the breathing circuit. After equilibration at an end-tidal-to-inspired desflurane concentration ratio >0.90 for 15 minutes, a 50-Hz, 80-mA electrical stimulus was applied to the antebrachium until a response was obtained (i.e. gross purposeful movement) or for up to 1 minute. The vaporizer setting was increased or decreased to effect a 10-20% change in end-tidal desflurane concentration, and equilibration and stimulus were repeated. The MAC was defined as the average of the lowest end-tidal desflurane concentration that prevented a positive response and the highest concentration that allowed a positive response. RESULTS Mean +/- SD MAC of desflurane was 7.99 +/- 0.58% in llamas and 7.83 +/- 0.51% in alpacas. CONCLUSIONS AND CLINICAL RELEVANCE The MAC of desflurane in llamas and alpacas was in the range of that reported for other species.
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Affiliation(s)
- Tamara L Grubb
- Department of Clinical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, OR, USA.
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Gómez-Villamandos RJ, Palacios C, Benítez A, Granados MM, Domínguez JM, López I, Ruiz I, Aguilera E, Santisteban JM. Dexmedetomidine or medetomidine premedication before propofol-desflurane anaesthesia in dogs. J Vet Pharmacol Ther 2006; 29:157-63. [PMID: 16669859 DOI: 10.1111/j.1365-2885.2006.00732.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The objective of this study was to evaluate dexmedetomidine as a premedicant in dogs prior to propofol-desflurane anaesthesia, and to compare it with medetomidine. Six healthy dogs were anaesthetized. Each dog received intravenously (i.v.) five preanaesthetic protocols: D1 (dexmedetomidine, 1 microg/kg, i.v.), D2 (dexmedetomidine, 2 microg/kg, i.v.), M1 (medetomidine, 1 microg/kg, i.v.), M2 (medetomidine, 2 microg/kg, i.v.), or M4 (medetomidine, 4 microg/kg, i.v.). Anaesthesia was induced with propofol (2.3-3.3 mg/kg) and maintained with desflurane. The following variables were studied: heart rate (HR), mean arterial pressure, systolic arterial pressure, diastolic arterial pressure, respiratory rate (RR), arterial oxygen saturation, end-tidal CO2, end-tidal concentration of desflurane (EtDES) required for maintenance of anaesthesia and tidal volume. Arterial blood pH (pHa) and arterial blood gas tensions (PaO2, PaCO2) were measured during anaesthesia. Time to extubation, time to sternal recumbency and time to standing were also recorded. HR and RR decreased significantly during sedation in all protocols. Cardiorespiratory variables during anaesthesia were statistically similar for all protocols. EtDES was significantly different between D1 (8.1%) and D2 (7.5%), and between all doses of medetomidine. Desflurane requirements were similar for D1 and M2, and for D2 and M4 protocols. No statistical differences were observed in recovery times. The combination of dexmedetomidine, propofol and desflurane appears to be effective for induction and maintenance of general anaesthesia in healthy dogs.
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Affiliation(s)
- R J Gómez-Villamandos
- Department of Animal Medicine and Surgery, Faculty of Veterinary Medicine, University of Córdoba, Campus Universitario de Rabanales, Córdoba, Spain.
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18
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Kästner SBR, Pakarinen SM, Ramela MP, Kutter APN, Boller J, Huhtinen MK. Comparative pharmacokinetics of medetomidine enantiomers in goats and sheep during sevoflurane anaesthesia. J Vet Pharmacol Ther 2006; 29:63-6. [PMID: 16420304 DOI: 10.1111/j.1365-2885.2006.00701.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- S B R Kästner
- Equine Clinic, Anaesthesia Section, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
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Gómez-Villamandos RJ, Redondo JI, Martín EM, Domínguez JM, Granados MM, Estepa JC, Ruiz I, Aguilera E, Santisteban JM. Romifidine or medetomidine premedication before propofol-sevoflurane anaesthesia in dogs. J Vet Pharmacol Ther 2005; 28:489-93. [PMID: 16207314 DOI: 10.1111/j.1365-2885.2005.00688.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- R J Gómez-Villamandos
- Department of Animal Medicine and Surgery, Faculty of Veterinary Medicine, University of Córdoba, Campus Universitario de Rabanales, Córdoba, Spain.
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20
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Kona-Boun JJ, Silim A, Troncy E. Immunologic aspects of veterinary anesthesia and analgesia. J Am Vet Med Assoc 2005; 226:355-63. [PMID: 15702683 DOI: 10.2460/javma.2005.226.355] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Jean-Jacques Kona-Boun
- Department of Clinical Sciences, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, QC, Canada
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Abstract
OBJECTIVE To determine hemodynamic effects of 3 concentrations of sevoflurane in cats. ANIMALS 6 cats. PROCEDURE Cats were anesthetized with sevoflurane in oxygen. After instruments were inserted, end-tidal sevoflurane concentration was set at 1.25, 1.5, or 1.75 times the individual minimum alveolar concentration (MAC), which was determined in another study. Twenty-five minutes were allowed after each change of concentration. Heart rate; systemic and pulmonary arterial pressures; central venous pressure; pulmonary artery occlusion pressure; cardiac output; body temperature; arterial and mixed-venous pH, PCO2, PO2, oxygen saturation, and hemoglobin concentrations; PCV; and total protein and lactate concentrations were measured for each sevoflurane concentration before and during noxious stimulation. Arterial and mixed-venous bicarbonate concentrations, cardiac index, stroke index, rate-pressure product, systemic and pulmonary vascular resistance indices, left and right ventricular stroke work indices, PaO2, mixed-venous partial pressure of oxygen (PVO2), oxygen delivery, oxygen consumption, oxygen-extraction ratio, alveolar-to-arterial oxygen difference, and venous admixture were calculated. Spontaneous and mechanical ventilations were studied during separate experiments. RESULTS Mode of ventilation did not significantly influence any of the variables examined. Therefore, data from both ventilation modes were pooled for analysis. Mean arterial pressure, cardiac index, stroke index, rate-pressure product, left ventricular stroke work index, arterial and mixed-venous pH, PaO2, and oxygen delivery decreased, whereas PaCO2, PVO2, and mixed-venous partial pressure of CO2 increased significantly with increasing doses of sevoflurane. Noxious stimulation caused a significant increase in most cardiovascular variables. CONCLUSIONS AND CLINICAL RELEVANCE Sevoflurane induces dose-dependent cardiovascular depression in cats that is mainly attributable to myocardial depression.
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Affiliation(s)
- Bruno H Pypendop
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
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22
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Grubb TL, Schlipf JW, Riebold TW, Cebra CK, Poland L, Zawadzkas X, Mailhot N. Minimum alveolar concentration of sevoflurane in spontaneously breathing llamas and alpacas. J Am Vet Med Assoc 2003; 223:1167-9. [PMID: 14584749 DOI: 10.2460/javma.2003.223.1167] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine the minimum alveolar concentration (MAC) of sevoflurane in spontaneously breathing llamas and alpacas. DESIGN Prospective study. ANIMALS 6 healthy adult llamas and 6 healthy adult alpacas. PROCEDURE Anesthesia was induced with sevoflurane delivered with oxygen through a mask. An endotracheal tube was inserted, and a port for continuous measurement of end-tidal and inspired sevoflurane concentrations was placed between the endotracheal tube and the breathing circuit. After equilibration at an end-tidal-to-inspired sevoflurane concentration ratio > 0.90 for 15 minutes, a 50-Hz, 80-mA electrical stimulus was applied to the antebrachium until a response was obtained (ie, gross purposeful movement) or for up to 1 minute. The vaporizer setting was increased or decreased to effect a 10 to 20% change in end-tidal sevoflurane concentration, and equilibration and stimulus were repeated. The MAC was defined as the mean of the lowest end-tidal sevoflurane concentration that prevented a positive response and the highest concentration that allowed a positive response. RESULTS Mean +/- SD MAC of sevoflurane was 2.29 +/- 0.14% in llamas and 2.33 +/- 0.09% in alpacas. CONCLUSIONS AND CLINICAL RELEVANCE The MAC of sevoflurane in llamas and alpacas was similar to that reported for other species.
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Affiliation(s)
- Tamara L Grubb
- Department of Clinical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA
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Setoyama K, Shinzato T, Misumi K, Fujiki M, Sakamoto H. Effects of Propofol-Sevoflurane Anesthesia on the Maternal and Fetal Hemodynamics Blood Gases, and Uterine Activity in Pregnant Goats. J Vet Med Sci 2003; 65:1075-81. [PMID: 14600344 DOI: 10.1292/jvms.65.1075] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To determine the effects of propofol and sevoflurane on hemodynamics, acid-base balance and uterine activity in pregnant animals, a prospective experimental study was designed by use of ten pregnant goats. Propofol was intravenously administered at a bolus dose of 5 mg/kg and then infused a rate of 0.3 mg/kg/min for 5 min. Following the induction, the animals were incrementally inhaled 2.7 and 4.1% of end-tidal concentration of sevoflurane each for 30 min, and then recovered. The maternal and fetal heart rate (HR), arterial blood pressure (BP) and acid-base balance, the intrauterine pressure (IUP), and the uterine blood flow (UBF) were measured. Following the pre-anesthetic data, the parameters were measured 7 times throughout the anesthetic and recovering periods. The propofol infusion induced 1.37 times of HR increase and produced decrease in PO(2) and a relevant metabolic acidemia in the mother, with no effect in the fetus. Sevoflurane reduced BP in the fetus from 30 (2.7%) to 60 (4.1%) min of inhalation. The uterine contractions disappeared throughout sevoflurane inhalation, and then recurred within 15 min after the cessation of sevoflurane. Propofol injection increases HR, and induces a moderate hypoxemia and metabolic acidemia associated with the suppressed ventilation for pregnant goats, with less effect on the fetal hemodinamics. Sevoflurane causes minimal change in maternal hemodynamics, but induces significant hypotension in the fetus and reduction of uterine activity. These data may be useful in making anesthetic choices combined with analgesia for Caesarian section in goats.
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Chittick EJ, Stamper MA, Beasley JFE, Lewbart GA, Horne WA. Medetomidine, ketamine, and sevoflurane for anesthesia of injured loggerhead sea turtles: 13 cases (1996-2000). J Am Vet Med Assoc 2002; 221:1019-25. [PMID: 12369681 DOI: 10.2460/javma.2002.221.1019] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine safety and efficacy of an anesthetic protocol incorporating medetomidine, ketamine, and sevoflurane for anesthesia of injured loggerhead sea turtles. DESIGN Retrospective study. ANIMALS 13 loggerhead sea turtles. PROCEDURE Anesthesia was induced with medetomidine (50 microg/kg [22.7 microg/lb], IV) and ketamine (5 mg/kg (2.3 mg/lb], IV) and maintained with sevoflurane (0.5 to 2.5%) in oxygen. Sevoflurane was delivered with a pressure-limited intermittent-flow ventilator. Heart rate and rhythm, end-tidal partial pressure of CO2, and cloacal temperature were monitored continuously; venous blood gas analyses were performed intermittently. Administration of sevoflurane was discontinued 30 to 60 minutes prior to the end of the surgical procedure. Atipamezole (0.25 mg/kg [0.11 mg/lb], IV) was administered at the end of surgery. RESULTS Median induction time was 11 minutes (range, 2 to 40 minutes; n = 11). Median delivered sevoflurane concentrations 15, 30, 60, and 120 minutes after intubation were 2.5 (n = 12), 1.5 (12), 1.25 (12), and 0.5% (8), respectively. Heart rate decreased during surgery to a median value of 15 beats/min (n = 11). End-tidal partial pressure of CO2 ranged from 2 to 16 mm Hg (n = 8); median blood gas values were within reference limits. Median time from atipamezole administration to extubation was 14 minutes (range, 2 to 84 minutes; n = 7). CONCLUSIONS AND CLINICAL RELEVANCE Results suggest that a combination of medetomidine and ketamine for induction and sevoflurane for maintenance provides safe, effective, controllable anesthesia in injured loggerhead sea turtles.
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Affiliation(s)
- Elizabeth J Chittick
- Environmental Medicine Consortium, College of Veterinary Medicine, North Carolina State University, Raleigh 27606, USA
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Cary JA, Hellyer PW. Anesthesia case of the month. Evaluation and treatment of suspected squamous cell carcinoma of the third eyelid. J Am Vet Med Assoc 2002; 221:790-2. [PMID: 12322914 DOI: 10.2460/javma.2002.221.790] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Julie A Cary
- Department of Clinical and Population Sciences, College of Veterinary Medicine, University of Minnesota, St Paul 55108, USA
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Abstract
Both desflurane and sevoflurane offer theoretical and practical advantages over other inhalation anesthetics for horses. The lower solubility of both agents provides improved control of delivery and helps to counteract the confounding influence of the voluminous patient breathing circuit commonly used for anesthetizing horses. The lower solubility should account for faster rates of recovery compared with the older agents; whether or not the quality of recovery differs remains to be objectively evaluated in a broad range of circumstances. The pharmacodynamic effects are, in large part, similar to those of isoflurane (e.g., low arrhythmogenicity) but with some differences. For example, desflurane may be overall more sparing to cardiovascular function (especially during controlled ventilation) compared with isoflurane and sevoflurane, which are roughly similar. Respiratory depression with both new agents is equal to or more depressing than isoflurane, suggesting the use of mechanical ventilation, especially in circumstances of prolonged management (i.e., hours of anesthesia). Both new anesthetics, not surprisingly, are expensive. From this point there are some agent-unique considerations. The anesthetic potency of both agents is less than that of isoflurane, which influences the cost of anesthesia, but also places an upper limit on inspired oxygen concentration (of particular concern with desflurane). Both agents require new vaporizers, but because of the high boiling point and steep vapor-pressure curve of desflurane, new technology was required. This translates into more costly equipment, adding to the cost of desflurane use. In addition, electricity is necessary for the new desflurane vaporizer to function, which limits its portability and adds additional practical considerations in its clinical use. On the other hand, desflurane strongly resists degradation both in vitro and in vivo, but in vitro degradation of sevoflurane by CO2 absorbents may produce renal injury. This may be true especially in association with low fresh-gas inflow rates (used to reduce the cost of using the new agent), and university based practices, where prolonged anesthesia is common.
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Affiliation(s)
- Eugene P Steffey
- Department of Surgical & Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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Martín E, Redondo JI, Molleda JM, Santisteban JM, López R, Gómez-Villamandos R. Effects of sevoflurane, isoflurane and halotane anaesthesia on fluorescein angiographic phases of dogs: a comparative study. JOURNAL OF VETERINARY MEDICINE. A, PHYSIOLOGY, PATHOLOGY, CLINICAL MEDICINE 2001; 48:267-75. [PMID: 11475901 DOI: 10.1046/j.1439-0442.2001.00341.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A fluorescein angiography method was developed to compare the onset and the total duration of the fluorangiographic phases between three anaesthetic protocols in six healthy mixed-breed dogs. The animals were anaesthetized three times. Each dog received, as pre-anaesthetic protocol, atropine (10 micrograms/kg intramuscularly), and as a sedative, romifidine (80 micrograms/kg intravenously). Fifteen minutes later, induction of anaesthesia was delivered with propofol (1 mg/kg intravenously) and maintained either with sevoflurane (SEVO group), isoflurane (ISO group) or halothane (HAL group) for 30 min in all cases. Some angiographic, cardiovascular and respiratory variables were registered during the procedure. Recovery times were also registered. Angiographic variables recorded were: onset of the arterial phase (TA), onset of the arteriovenous phase (TAV), onset of the venous phase (TV), complete arterial phase duration (I1), complete arteriovenous phase duration (I2) and I1 plus I2 (I3). Mean heart rate, mean arterial pressure, systolic arterial pressure, diastolic arterial pressure, respiratory rate, tidal volume, arterial oxygen saturation and end-tidal CO2 during SEVO and ISO anaesthesia, were similar in dogs. Minute ventilation and rectal temperature were higher in dogs with SEVO than ISO. HAL produced higher arterial pressures and a lower arterial oxygen saturation than ISO and SEVO. Mean respiratory rate, rectal temperature and minute ventilation were higher in HAL. Pulse rate, end-tidal CO2 and tidal volume were similar in the dogs of the three groups. No differences in recovery times were found. The fluorescein angiographic times were within the normal range. There were no significant differences between protocols in I1, I2 or I3. HAL produced a significant increase of all temporal variables (TA, TAV and TV) when compared with ISO; TA was higher in HAL than SEVO-treated dogs. All protocols appear to be safe and effective for inducing and maintaining general anaesthesia in healthy dogs for performing fluorescein angiography.
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Affiliation(s)
- E Martín
- Department of Animal Medicine and Surgery, Faculty of Veterinary Medicine, University of Cordoba, Campus Universitario de Rabanales, Ctra. Madrid-Cádiz, Km. 396., 14014, Córdoba, Spain
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Affiliation(s)
- H Haitjema
- Division of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, Western Australia 6150
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Abstract
Providing a safe anesthetic environment is the key to successful avian anesthesia. Knowledge and understanding the anatomic and physiologic differences between birds and mammals help to prevent most emergency situations and guide responses in critical situations. Thorough preanesthetic history and examination, correction of underlying conditions, and use of simple anesthetic protocols all optimize the outcome of the procedure. Finally, critical monitoring helps to anticipate most crises and reduces incidences of mortality and morbidity in avian anesthesia.
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Affiliation(s)
- N Abou-Madi
- Division of Wildlife Health, Department of Clinical Sciences, Cornell University, College of Veterinary Medicine, Ithaca, New York, USA
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Tzannes S, Govendir M, Zaki S, Miyake Y, Packiarajah P, Malik R. The use of sevoflurane in a 2:1 mixture of nitrous oxide and oxygen for rapid mask induction of anaesthesia in the cat. J Feline Med Surg 2000; 2:83-90. [PMID: 11716598 DOI: 10.1053/jfms.2000.0083] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
An inhalational technique for rapid induction of anaesthesia in unsedated cats using sevoflurane and nitrous oxide is described. Using a pliable, tight-fitting, face mask, sevoflurane (7.5-8%) was delivered from an out-of-circuit precision vaporiser connected to a coaxial non-rebreathing system using a fresh gas flow of 1 l oxygen and 2 l nitrous oxide per min. Cats were restrained with gentle but firm pressure applied by scruffing the dorsal cervical skin until the righting reflex was lost and the patient could be positioned in lateral recumbency. Typically, cats could be positioned on their side in a light plane of anaesthesia within 1 min of applying the mask, at which time the sevoflurane concentration was reduced to 5% or less. A similar protocol, using a lower initial concentration of sevoflurane, is recommended for old or debilitated patients. Maintenance of light sevoflurane (2-4%) anaesthesia by mask permitted minor interventions to be performed readily, including blood collection, intravenous chemotherapy, abdominal palpation, radiography and ultrasonography. More painful procedures, such as bone marrow aspiration, required a deeper plane of anaesthesia. Cats were sufficiently deep to be intubated, if this was required, about 3 min after commencing the induction. Recovery from sevoflurane/nitrous oxide anaesthesia was smooth and rapid, with most cats being able to right within 5 min of discontinuing the agents. This protocol for rapid inhalational induction and recovery is particularly suited to feline practice, where rendering an uncooperative patient unconscious greatly facilitates the completion of many minor diagnostic and therapeutic procedures, especially when these must be performed on successive days or when peripheral vascular access is limited. For longer procedures, isoflurane may be substituted for sevoflurane for maintenance of anaesthesia in order to minimise cost.
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Affiliation(s)
- S Tzannes
- Anaesthesia Unit, University Veterinary Centre Sydney, Department of Veterinary Clinical Sciences, The University of Sydney, New South Wales, Australia 2006
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