Compendium January 2009

1. Compendium
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4. January
2009 Vol 31(1)
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EDITORIAL BOARD
Anesthesia Internal Medicine
Nora S. Matthews, DVM, DACVA Dana G. Allen, DVM, MSc, DACVIM
AMERICAN
Texas A&M University Ontario Veterinary College BOARD OF
Cardiology Internal Medicine and Emergency/ VETERINARY
Bruce Keene, DVM, MSc, DACVIM Critical Care PRACTITIONERS
North Carolina State University Alison R. Gaynor, DVM, DACVIM (ABVP) REVIEW
(Internal Medicine), DACVECC
Clinical Chemistry, Hematology,
North Grafton, Massachusetts
BOARD
and Urinalysis
Betsy Welles, DVM, PhD, DACVP Nephrology Eric Chafetz, DVM, DABVP
Auburn University Catherine E. Langston, DVM, ACVIM (Canine/Feline)
Animal Medical Center
Dentistry Vienna Animal Hospital
New York, New York
Gary B. Beard, DVM, DAVDC Vienna, Virginia
Auburn University Neurology Canine and Feline Medicine
EDITOR IN CHIEF R. Michael Peak, DVM, DAVDC
Curtis W. Dewey, DVM, MS, DACVIM
(Neurology), DACVS Henry E. Childers, DVM,
Douglass K. Macintire, The Pet Dentist—Tampa Bay Veterinary
Cornell University Hospital for Animals
Dentistry DABVP (Canine/Feline)
DVM, MS, DACVIM, DACVECC
Largo, Florida Oncology Cranston Animal Hospital
Department of Clinical Sciences Ann E. Hohenhaus, DVM, DACVIM Cranston, Rhode Island
College of Veterinary Medicine Emergency/Critical Care and
(Oncology and Internal Medicine) Canine and Feline Medicine
Auburn University, AL 36849 Respiratory Medicine
Animal Medical Center
Lesley King, MVB, MRCVS, DACVECC,
New York, New York
DACVIM David E. Harling, DVM,
University of Pennsylvania Gregory K. Ogilvie, DVM, DACVIM DABVP (Canine/Feline),
(Internal Medicine and Oncology) DACVO
Endocrinology and Metabolic Disorders
CVS Angel Care Cancer Center and Special Reidsville Veterinary Hospital
Marie E. Kerl, DVM, ACVIM, ACVECC
Care Foundation for Companion Animals Reidsville, North Carolina
University of Missouri-Columbia
San Marcos, California Canine and Feline Medicine,
EXECUTIVE Epidemiology
Ophthalmology Ophthalmology
ADVISORY Philip H. Kass, DVM, MPVM, MS, PhD,
David A. Wilkie, DVM, MS, DACVO
BOARD DACVPM
The Ohio State University Jeffrey Katuna, DVM, DABVP
University of California, Davis
MEMBERS Parasitology Wellesley-Natick Veterinary
Exotics
Byron L. Blagburn, MS, PhD Hospital
Avian
Behavior Auburn University Natick, Massachusetts
Thomas N. Tully, Jr, DVM, MS, DABVP
Sharon L. Crowell-Davis, (Avian), ECAMS David S. Lindsay, PhD
Canine and Feline Medicine
DVM, PhD, DACVB Louisiana State University Virginia Polytechnic Institute
The University of Georgia and State University Robert J. Neunzig, DVM,
Reptiles
DABVP (Canine/Feline)
Douglas R. Mader, MS, DVM, DABVP (DC) Pharmacology
Dermatology Marathon Veterinary Hospital Katrina L. Mealey, DVM, PhD, DACVIM,
The Pet Hospital
Craig E. Griffin, DVM, Marathon, Florida DACVCP Bessemer City, North Carolina
Washington State University Canine and Feline Medicine
DACVD Small Mammals
Animal Dermatology Clinic Karen Rosenthal, DVM, MS, DABVP Rehabilitation and Physical Therapy
San Diego, California (Avian) Darryl Millis, MS, DVM, DACVS
University of Pennsylvania University of Tennessee
Wayne S. Rosenkrantz, Feline Medicine Surgery Compendium is a
DVM, DACVD Michael R. Lappin, DVM, PhD, Philipp Mayhew, BVM&S, MRCVS, refereed journal. Articles
Animal Dermatology Clinic DACVIM (Internal Medicine) DACVS
Colorado State University Columbia River Veterinary Specialists
published herein have
Tustin, California been reviewed by at least
Vancouver, Washington
Margie Scherk, DVM, DAVBP
(Feline Medicine) C. Thomas Nelson, DVM
two academic experts on
Nutrition the respective topic and
Cats Only Veterinary Clinic Animal Medical Center
Kathryn E. Michel, DVM, Vancouver, British Columbia Anniston, Alabama by an ABVP practitioner.
MS, DACVN
Gastroenterology Surgery and Orthopedics
University of Pennsylvania
Debra L. Zoran, DVM, MS, PhD, Ron Montgomery, DVM, MS, DACVS
DACVIM (Internal Medicine) Auburn University
Surgery Texas A&M University Any statements, claims, or product
Toxicology
Elizabeth M. Hardie, endorsements made in Compendium
Infectious Disease Tina Wismer, DVM, DABVT, DABT
DVM, PhD, DACVS are solely the opinions of our authors
Derek P. Burney, PhD, DVM ASPCA National Animal Poison Control and advertisers and do not necessarily
North Carolina State Gulf Coast Veterinary Specialists Center reflect the views of the Publisher or
University Houston, Texas Urbana, Illinois Editorial Board.
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Important Information: How Supplied: SevoFlo is packaged in amber colored bottles containing 250 mL sevoflurane. Indications:
SevoFlo is indicated for induction and maintenance of general anesthesia in dogs. Warnings, Precautions, and Contraindications:
Like other inhalation anesthetics, sevoflurane is a profound respiratory depressant. Respiration must be monitored closely in the
dog and supported when necessary with supplemental oxygen and/or assisted ventilation. Due to sevoflurane’s low solubility
in blood, increasing concentration may result in rapid hemodynamic changes compared to other volatile anesthetics. SevoFlo
is contraindicated in dogs with a known sensitivity to sevoflurane or other halogenated agents. Adverse Reactions: The most
frequently reported adverse reactions during maintenance anesthesia were hypotension, followed by tachypnea, muscle
tenseness, excitation, apnea, muscle fasciculations and emesis. See package insert for full prescribing information.
See Page 4 for Product Information Summary
SEVO-186
June 2008
©2008 Abbott Laboratories

6. PRECAUTIONS: Halogenated volatile anesthetics can react with desiccated decreased at hourly intervals, from 500 mL/min (36 and 18 ppm Compound A) to 250
SevoFlo® 5458 carbon dioxide (CO2) absorbents to produce carbon monoxide (CO) that may mL/min (43 and 31 ppm) to 50 mL/min (61 and 48 ppm).8
(sevoflurane) result in elevated carboxyhemoglobin levels in some patients. To prevent this Fluoride ion metabolite: Sevoflurane is metabolized to hexafluoroisopropanol (HFIP)
reaction, sevoflurane should not be passed through desiccated soda lime or with release of inorganic fluoride and CO2. Fluoride ion concentrations are influenced by
Inhalation Anesthetic For Use in Dogs
barium hydroxide lime. the duration of anesthesia and the concentration of sevoflurane. Once formed, HFIP is
Caution: Federal law restricts this drug to use by or on the order of a
Replacement of Desiccated CO2 Absorbents: When a clinician suspects rapidly conjugated with glucuronic acid and eliminated as a urinary metabolite. No other
licensed veterinarian.
that the CO2 absorbent may be desiccated, it should be replaced before metabolic pathways for sevoflurane have been identified. In humans, the fluoride ion
DESCRIPTION: SevoFlo (sevoflurane), a volatile liquid, is a halogenated
administration of sevoflurane. The exothermic reaction that occurs with half-life was prolonged in patients with renal impairment, but human clinical trials
general inhalation anesthetic drug. Its chemical name is fluoromethyl 2,2,2-
sevoflurane and CO2 absorbents is increased when the CO2 absorbent contained no reports of toxicity associated with elevated fluoride ion levels. In a study in
trifluoro-l- (trifluoromethyl) ethyl ether, and its structural formula is:
becomes desiccated, such as after an extended period of dry gas flow through which 4 dogs were exposed to 4% sevoflurane for 3 hours, maximum serum fluoride
the CO2 absorbent canisters. Extremely rare cases of spontaneous fire in the concentrations of 17.0-27.0 mcmole/L were observed after 3 hours of anesthesia.
respiratory circuit of the anesthesia machine have been reported during Serum fluoride fell quickly after anesthesia ended, and had returned to baseline by 24
sevoflurane use in conjunction with the use of a desiccated CO2 absorbent, hours post-anesthesia. In a safety study, eight healthy dogs were exposed to
specifically those containing potassium hydroxide (e.g. BARALYME). sevoflurane for 3 hours/day, 5 days/week for 2 weeks (total 30 hours exposure) at a
Potassium hydroxide containing CO2 absorbents are not recommended for use flow rate of 500 mL/min in a semi-closed, rebreathing system with soda lime. Renal
Sevoflurane Physical Constants are: with sevoflurane. An unusually delayed rise in the inspired gas concentration toxicity was not observed in the study evaluation of clinical signs, hematology, serum
Molecular weight 200.05 (decreased delivery) of sevoflurane compared with the vaporizer setting may chemistry, urinalysis, or gross or microscopic pathology.
Boiling point at 760 mm Hg 58.6°C indicate excessive heating of the CO2 absorbent canister and chemical DRUG INTERACTIONS: In the clinical trial, sevoflurane was used safely in dogs that
Specific gravity at 20°C 1.520-1.525 g/mL breakdown of sevoflurane. The color indicator of most CO2 absorbent may not received frequently used veterinary products including steroids and heartworm and flea
Vapor pressure in mm Hg at 20°C 157 change upon desiccation. Therefore, the lack of significant color change preventative products.
at 25°C 197 should not be taken as an assurance of adequate hydration. CO2 absorbents Intravenous Anesthetics: Sevoflurane administration is compatible with barbiturates,
at 36°C 317 should be replaced routinely regardless of the state of the color indicator. propofol and other commonly used intravenous anesthetics. Benzodiazepines and
Distribution Partition Coefficients at 37°C: Opioids: Benzodiazepines and opioids would be expected to decrease the MAC of
The use of some anesthetic regimens that include sevoflurane may result in
Blood/Gas 0.63-0.69 sevoflurane in the same manner as other inhalational anesthetics. Sevoflurane is
bradycardia that is reversible with anticholinergics. Studies using sevoflurane
Water/Gas 0.36 compatible with benzodiazepines and opioids as commonly used in surgical practice.
anesthetic regimens that included atropine or glycopyrrolate as premedicants
Olive Oil/Gas 47-54 Phenothiazines and Alpha2-Agonists: Sevoflurane is compatible with phenothiazines
showed these anticholinergics to be compatible with sevoflurane in dogs.
Brain/Gas 1.15 and alpha2- agonists as commonly used in surgical practice.
During the induction and maintenance of anesthesia, increasing the
Mean Component/Gas Partition Coefficients at 25°C for Polymers Used In a laboratory study, the use of the acepromazine/oxymorphone/ thiopental/sevoflurane
concentration of sevoflurane produces dose dependent decreases in blood
Commonly in Medical Applications: anesthetic regimen resulted in prolonged recoveries in eight (of 8) dogs compared to
pressure and respiratory rate. Due to sevoflurane’s low solubility in blood,
Conductive rubber 14.0 recoveries from sevoflurane alone.
these changes may occur more rapidly than with other volatile anesthetics.
Butyl rubber 7.7 CLINICAL EFFECTIVENESS:
Excessive decreases in blood pressure or respiratory depression may be
Polyvinyl chloride 17.4 The effectiveness of sevoflurane was investigated in a clinical study involving 196 dogs.
related to depth of anesthesia and may be corrected by decreasing the
Polyethylene 1.3 Thirty dogs were mask-induced with sevoflurane using anesthetic regimens that
inspired concentration of sevoflurane. RESPIRATION MUST BE MONITORED
included various premedicants. During the clinical study, one hundred sixty-six dogs
CLOSELY IN THE DOG AND SUPPORTED WHEN NECESSARY WITH
Sevoflurane is nonflammable and nonexplosive as defined by the requirements of received sevoflurane maintenance anesthesia as part of several anesthetic regimens
SUPPLEMENTAL OXYGEN AND/OR ASSISTED VENTILATION. The low
International Electrotechnical Commission 601-2-13. Sevoflurane is a clear, that used injectable induction agents and various premedicants. The duration of
solubility of sevoflurane also facilitates rapid elimination by the lungs.
colorless, stable liquid containing no additives or chemical stabilizers. anesthesia and the choice of anesthetic regimens were dependent upon the procedures
The use of sevoflurane in humans increases both the intensity and duration of
Sevoflurane is nonpungent. It is miscible with ethanol, ether, chloroform and that were performed. Duration of anesthesia ranged from 16 to 424 minutes among the
neuromuscular blockade induced by nondepolarizing muscle relaxants. The
petroleum benzene, and it is slightly soluble in water. Sevoflurane is stable when individual dogs. Sevoflurane vaporizer concentrations during the first 30 minutes of
use of sevoflurane with nondepolarizing muscle relaxants has not been
stored under normal room lighting condition according to instructions. maintenance anesthesia were similar among the various anesthetic regimens. The
evaluated in dogs.
INDICATIONS: SevoFlo is indicated for induction and maintenance of general quality of maintenance anesthesia was considered good or excellent in 169 out of 196
Compromised or debilitated dogs: Doses may need adjustment for geriatric or
anesthesia in dogs. dogs. The table shows the average vaporizer concentrations and oxygen flow rates
debilitated dogs. Because clinical experience in administering sevoflurane to
DOSAGE AND ADMINISTRATION: Inspired Concentration: The delivered during the first 30 minutes for all sevoflurane maintenance anesthesia regimens:
dogs with renal, hepatic and cardiovascular insufficiency is limited, its safety in
concentration of SevoFlo should be known. Since the depth of anesthesia may these dogs has not been established.
be altered easily and rapidly, only vaporizers producing predictable percentage Average Average Average Average
Breeding dogs: The safety of sevoflurane in dogs used for breeding purposes, Vaporizer Vaporizer Oxygen Oxygen
concentrations of sevoflurane should be used. Sevoflurane should be vaporized during pregnancy, or in lactating bitches, has not been evaluated. Concentrations Concentrations Flow Flow
using a precision vaporizer specifically calibrated for sevoflurane. Sevoflurane Neonates: The safety of sevoflurane in young dogs (less than 12 weeks of among among Rates Rates
contains no stabilizer. Nothing in the drug product alters calibration or operation age) has not been evaluated. Anesthetic Individual among among
of these vaporizers. The administration of general anesthesia must be HUMAN SAFETY: Not for human use. Keep out of reach of children.
Regimens Dogs Anesthetic Individual
individualized based on the patient’s response. WHEN USING SEVOFLURANE, Regimens Dogs
Operating rooms and animal recovery areas should be provided with 3.31 - 3.63% 1.6 - 5.1% 0.97 - 1.31 0.5 - 3.0
PATIENTS SHOULD BE CONTINUOUSLY MONITORED AND FACILITIES adequate ventilation to prevent the accumulation of anesthetic vapors. L/minute L/minute
FOR MAINTENANCE OF PATENT AIRWAY, ARTIFICIAL VENTILATION, AND There is no specific work exposure limit established for sevoflurane. However,
OXYGEN SUPPLEMENTATION MUST BE IMMEDIATELY AVAILABLE. the National Institute for Occupational Safety and Health has recommended an During the clinical trial, when a barbiturate was used for induction, the times to
Replacement of Desiccated CO2 Absorbents: When a clinician suspects that 8 hour time-weighted average limit of 2 ppm for halogenated anesthetic agents extubation, sternal recumbency and standing recovery were longer for dogs that
the CO2 absorbent may be desiccated, it should be replaced. An exothermic in general. Direct exposure to eyes may result in mild irritation. If eye exposure received anesthetic regimens containing two preanesthetics compared to regimens
reaction occurs when sevoflurane is exposed to CO2 absorbents. This reaction is containing one preanesthetic. Recovery times were shorter when anesthetic regimens
occurs, flush with plenty of water for 15 minutes. Seek medical attention if
increased when the CO2 absorbent becomes desiccated (see PRECAUTIONS). irritation persists. Symptoms of human overexposure (inhalation) to used sevoflurane or propofol for induction. The quality of recovery was considered good
Premedication: No specific premedication is either indicated or contraindicated sevoflurane vapors include respiratory depression, hypotension, bradycardia, or excellent in 184 out of 196 dogs. Anesthetic regimen drug dosages, physiological
with sevoflurane. The necessity for and choice of premedication is left to the shivering, nausea and headache. If these symptoms occur, remove the responses, and the quality of induction, maintenance and recovery were comparable
discretion of the veterinarian. Preanesthetic doses for premedicants may be between 10 sighthounds and other breeds evaluated in the study. During the clinical
individual from the source of exposure and seek medical attention. The
lower than the label directions for their use as a single medication.1 material safety data sheet (MSDS) contains more detailed occupational safety study there was no indication of prolonged recovery times in the sighthounds.
Induction: For mask induction using sevoflurane alone, inspired concentrations information. For customer service, adverse effects reporting, and/or a HOW SUPPLIED: SevoFlo (sevoflurane) is packaged in amber colored bottles
up to 7% sevoflurane with oxygen are employed to induce surgical anesthesia in copy of the MSDS, call (888) 299-7416. containing 250 mL sevoflurane, List 5458.
the healthy dog. These concentrations can be expected to produce surgical STORAGE CONDITIONS: Store at controlled room temperature 15°-30°C (59°-86°F).
CLINICAL PHARMACOLOGY: Sevoflurane is an inhalational anesthetic
anesthesia in 3 to 14 minutes. Due to the rapid and dose dependent changes agent for induction and maintenance of general anesthesia. The Minimum REFERENCES:
in anesthetic depth, care should be taken to prevent overdosing. Alveolar Concentration (MAC) of sevoflurane as determined in 18 dogs is 1. Plumb, D.C. ed., Veterinary Drug Handbook, Second Edition, University of Iowa
Respiration must be monitored closely in the dog and supported when 2.36%.2 MAC is defined as that alveolar concentration at which 50% of healthy Press, Ames, IA: p. 424 (1995).
necessary with supplemental oxygen and/or assisted ventilation. patients fail to respond to noxious stimuli. Multiples of MAC are used as a 2. Kazama, T. and Ikeda, K., Comparison of MAC and the rate of rise of alveolar
Maintenance: SevoFlo may be used for maintenance anesthesia following mask guide for surgical levels of anesthesia, which are typically 1.3 to 1.5 times the concentration of sevoflurane with halothane and isoflurane in the dog. Anesthesiology.
induction using sevoflurane or following injectable induction agents. The MAC value. Because of the low solubility of sevoflurane in blood (blood/gas 68: 435-437 (1988).
concentration of vapor necessary to maintain anesthesia is much less than that partition coefficient at 37°C = 0.63-0.69), a minimal amount of sevoflurane is 3. Scheller, M.S., Nakakimura, K., Fleischer, J.E. and Zornow, M.H., Cerebral effects of
required to induce it. Surgical levels of anesthesia in the healthy dog may be required to be dissolved in the blood before the alveolar partial pressure is in sevoflurane in the dog: Comparison with isoflurane and enflurane. Brit. J. Anesthesia
maintained with inhaled concentrations of 3.7-4.0% sevoflurane in oxygen in the equilibrium with the arterial partial pressure. During sevoflurane induction, 65: 388-392 (1990).
absence of premedication and 3.3-3.6% in the presence of premedication. The there is a rapid increase in alveolar concentration toward the inspired 4. Frink, E.J., Morgan, S.E., Coetzee, A., Conzen, P.F. and Brown, B.R., Effects of
use of injectable induction agents without premedication has little effect on the concentration. Sevoflurane produces only modest increases in cerebral blood sevoflurane, halothane, enflurane and isoflurane on hepatic blood flow and oxygenation
concentrations of sevoflurane required for maintenance. Anesthetic regimens that flow and metabolic rate, and has little or no ability to potentiate seizures.3 in chronically instrumented greyhound dogs. Anesthesiology 76: 85-90 (1992).
include opioid, alpha2-agonist, benzodiazepine or phenothiazine premedication Sevoflurane has a variable effect on heart rate, producing increases or 5. Kazama, T. and Ikeda, K., The comparative cardiovascular effects of sevoflurane
will allow the use of lower sevoflurane maintenance concentrations. decreases depending on experimental conditions.4,5 Sevoflurane produces with halothane and isoflurane. J. Anesthesiology 2: 63-8 (1988).
CONTRAINDICATIONS: SevoFlo is contraindicated in dogs with a known dose-dependent decreases in mean arterial pressure, cardiac output and 6. Bernard, J. M., Wouters, P.F., Doursout, M.F., Florence, B., Chelly, J.E. and Merin,
sensitivity to sevoflurane or other halogenated agents. myocardial contraction.6 Among inhalation anesthetics, sevoflurane has low R.G., Effects of sevoflurane on cardiac and coronary dynamics in chronically
WARNINGS: Sevoflurane is a profound respiratory depressant. DUE TO THE arrhythmogenic potential.7 Sevoflurane is chemically stable. No discernible instrumented dogs. Anesthesiology 72: 659-662 (1990).
RAPID AND DOSE DEPENDENT CHANGES IN ANESTHETIC DEPTH, degradation occurs in the presence of strong acids or heat. Sevoflurane reacts 7. Hayaski, Y., Sumikawa, K., Tashiro, C., Yamatodani, A. and Yoshiya, I.,
RESPIRATION MUST BE MONITORED CLOSELY IN THE DOG AND through direct contact with CO2 absorbents (soda lime and barium hydroxide Arrhythmogenic threshold of epinephrine during sevoflurane, enflurane and isoflurane
SUPPORTED WHEN NECESSARY WITH SUPPLEMENTAL OXYGEN lime) producing pentafluoroisopropenyl fluoromethyl ether (PIFE, C4H2F6O), anesthesia in dogs. Anesthesiology 69: 145-147 (1988).
AND/OR ASSISTED VENTILATION. also known as Compound A, and trace amounts of pentafluoromethoxy 8. Muir, W.W. and Gadawski, J., Cardiorespiratory effects of low-flow and closed circuit
In cases of severe cardiopulmonary depression, discontinue drug administration, isopropyl fluoromethyl ether (PMFE, C5H6F6O), also known as Compound B. inhalation anesthesia, using sevoflurane delivered with an in-circuit vaporizer and
ensure the existence of a patent airway and initiate assisted or controlled Compound A: The production of degradants in the anesthesia circuit results concentrations of compound A. Amer. J. Vet. Res. 59 (5): 603-608 (1998).
ventilation with pure oxygen. Cardiovascular depression should be treated with from the extraction of the acidic proton in the presence of a strong base
plasma expanders, pressor agents, antiarrhythmic agents or other techniques as (potassium hydroxide and/or NaOH) forming an alkene (Compound A) from NADA 141-103, Approved by FDA
appropriate for the observed abnormality. Due to sevoflurane’s low solubility in SevoFlo® is a registered trademark of Abbott Laboratories.
sevoflurane.
blood, increasing the concentration may result in rapid changes in anesthetic Compound A is produced when sevoflurane interacts with soda lime or barium Manufactured by Abbott Laboratories, North Chicago, IL
depth and hemodynamic changes (dose dependent decreases in respiratory rate hydroxide lime. Reaction with barium hydroxide lime results in a greater 60064, USA
and blood pressure) compared to other volatile anesthetics. Excessive decreases production of Compound A than does reaction with soda lime. Its concentration Product of Japan
in blood pressure or respiratory depression may be corrected by decreasing or in a circle absorber system increases with increasing sevoflurane
discontinuing the inspired concentration of sevoflurane. Under license from
concentrations and with decreasing fresh gas flow rates. Sevoflurane Maruishi Pharmaceutical Co., LTD
Potassium hydroxide containing CO2 absorbents (e.g. BARALYME®) are not degradation in soda lime has been shown to increase with temperature. Since 2-3-5, Fushimi-Machi, Chuo-Ku,
recommended for use with sevoflurane. the reaction of carbon dioxide with absorbents is exothermic, this temperature Osaka, Japan
ADVERSE REACTIONS: The most frequently reported adverse reactions during increase will be determined by the quantities of CO2 absorbed, which in turn
maintenance anesthesia were hypotension, followed by tachypnea, muscle For customer service call (888) 299-7416.
will depend on fresh gas flow in the anesthetic circle system, metabolic status
tenseness, excitation, apnea, muscle fasciculations and emesis. of the patient and ventilation. Although Compound A is a dose-dependent
Infrequent adverse reactions include paddling, retching, salivation, cyanosis, ©Abbott 8/2006
nephrotoxin in rats, the mechanism of this renal toxicity is unknown. Two Taken from Commodity Number 03-5474/R6, SevoFlo, sevoflurane, package insert, January 11, 2007
premature ventricular contractions and excessive cardiopulmonary depression. spontaneously breathing dogs under sevoflurane anesthesia showed
Transient elevations in liver function tests and white blood cell count may occur
increases in concentrations of Compound A as the oxygen flow rate was
with sevoflurane, as with the use of other halogenated anesthetic agents.
SEVO-152 January 2007 page 1 of 1 ©2007 Abbott Laboratories

7. E
Each CE article is accredited for 3 contact hours by
CE A
Auburn University College of Veterinary Medicine. Section Name
January 2009 Vol 31(1)
Features
8 Understanding Behavior CompendiumVet.com | Peer Reviewed | Listed in MEDLINE
Behavior Assessment: The First Appointment
❯❯ Sharon L. Crowell-Davis
Once a behavior prob- An In-Depth Look FREE
lem has been identi-
fied and described, the
14 The Diagnostic Approach to CE
circumstances in which it Fever of Unknown Origin in D
Dogs
occurs must be clarified. ❯❯ Julie Flood
This is the second article
in this series on behav- FREE
ior patient assessment. 26 The Diagnostic Approach to CE
Fever of Unknown Origin in C t
Cats
22 Focus on Nutrition
NEW ❯❯ Julie Flood
Using a Diet History to Improve Fever is a common clinical sign in dogs and
Adherence to Dietary Recommendations
i cats, but its cause is not always apparent.
❯❯ Kathryn E. Michel These articles present a thorough overview
of physical examination findings and diag-
The first article in this quarterly series explains
nostic tests that can help guide diagnosis of
how to effectively use diet history forms and
the underlying condition.
what information is most important.
33 Immunosuppressive Therapy for Canine
ine
Immune-Mediated Hemolytic Anemia FREE
❯❯ Suliman Al-Ghazlat CE
The author describes the range of
current treatment options for dogs with this
potentially deadly condition.
47 Focus on Nutrition
Sample Diet History Form
This form is also downloadable from
CompendiumVet.com.
Departments
6 Editorial: Clinical Snapshot
Focus on Nutrition PAGE 11
❯❯ Kathryn E. Michel
14
7 CompendiumVet.com
©2009 iofoto/Shutterstock.com
11 Clinical Snapshot
A Dog with “Bumps”
on its Skin
On the Cover
❯❯ Karen A. Moriello Starting on page 14, Dr. Julie Flood de-
scribes the diagnostic approach to fever
25 Letters
of unknown origin in dogs and cats.
32 Product Forum 45 Classified Advertising Supplemental material to both articles
45 Market Showcase 46 Index to Advertisers is available at CompendiumVet.com.
CompendiumVet.com 5

8. Editorial
❯❯ Kathryn E. Michel, DVM, MS, DACVN, University of Pennsylvania
Focus on Nutrition
The goal of this new quarterly column is to provide veterinary
health professionals with state-of-the-art information on best
practices for the nutritional management of companion animals.
D etermining and implementing the The articles will be written by members
appropriate dietary management of of the ACVN, the recognized specialty board
companion animals have long been in this area of expertise. The column will
recognized by the veterinary profession as also include information about the ACVN, the
key components of maintaining wellness and services its diplomates can offer to practicing
treating disease. Now, pet owners are increas- veterinarians, and resources for those who
ingly aware of the benefits and risks that cer- may be interested in specializing in the field
tain dietary habits may entail. In the present of nutrition.
“information age,” it is a growing challenge for We all know that diet is a subject of great
veterinary practitioners to stay abreast of this concern to many pet owners and one about
dynamic field to be able to offer their clients which people often hold strong opinions. It
accurate information about companion animal can be a sensitive subject to broach, and it is
nutrition and diet choices and their patients often difficult to get clients to adhere to the
the latest advances in nutritional management. dietary recommendations we make for their
pets. I hope that Focus on Nutrition will help
We all know that diet is a subject of great veterinary health professionals become more
concern to many pet owners and one about informed on entering into and feel more con-
fident when
this subject
a dialogue on diet
which people often hold strong opinions. and dietary management with their clients
to ensure the best possible outcome for their
In order to help practitioners meet this patients.
challenge, this issue of Compendium is launch-
ing the Focus on Nutrition series in collabora-
tion with the American College of Veterinary SHARE YOUR COMMENTS
Nutrition (ACVN). This new column, which will Have something to say about this
appear quarterly, is devoted to current topics in editorial or topic? Let us know:
small animal nutrition. The goal is to provide
E-MAIL editor@CompendiumVet.com
veterinary health professionals with state-of-
the-art information on best practices for the FAX 800-556-3288
nutritional management of companion animals,
both to maintain wellness and to treat disease.
6 Compendium: Continuing Education for Veterinarians® | January 2009 | CompendiumVet.com