Isoflurane and sevoflurane provide equally effective anesthesia in laboratory mice

131 Pages·2014·1.22 MB·English

by  Cesarovic Nikola

ETH Library
Optimization of anesthetic
protocols and their impact on
physiological and behavioral
parameters in laboratory mice
Doctoral Thesis
Author(s):
Ćesarović, Nikola
Publication date:
2014
Permanent link:
https://doi.org/10.3929/ethz-a-010124123
Rights / license:
In Copyright - Non-Commercial Use Permitted
This page was generated automatically upon download from the ETH Zurich Research Collection.
For more information, please consult the Terms of use.
o
Diss. ETH N 21673

Optimization of Anesthetic Protocols and their Impact on
Physiological and Behavioral Parameters in Laboratory Mice

A dissertation submitted to
ETH ZURICH

for the degree of
Doctor of Sciences

presented by

NIKOLA ĆESAROVIĆ

Dr. med. vet.
Vetsuisse Faculty, University of Zürich

Date of birth
10.07.1980

citizen of
Belgrade, Republic of Serbia

accepted on the recommendation of

Professor Dr. W. Langhans, examiner
Professor Dr. B. Beck Schimmer, co-examiner
PD Dr. M. Arras, co-examiner

2014
Table of Contents

Table of Contents

List of Tables and Figures .................................................................................................... VI
List of Abbreviations ........................................................................................................... VIII
Summary ............................................................................................................................. XII
Zusammenfassung ............................................................................................................. XIV
Chapter 1: General Introduction ...........................................................................................17
General anesthesia in small laboratory rodents .................................................................18
Inhalation anesthesia in laboratory routine .....................................................................19
Isoflurane .......................................................................................................................20
Sevoflurane ....................................................................................................................20
Minimum Alveolar Concentration (MAC)............................................................................21
Balanced anesthesia .........................................................................................................22
Post-operative pain in mice—its detection and treatment challenges ................................23
Methods of gathering physiological data in undisturbed animals .......................................24
Telemetry .......................................................................................................................24
Objectives and thesis outline ................................................................................................27
Chapter 2: Implantation of radiotelemetry transmitters yielding data on ECG, heart rate, core
body temperature and activity in free-moving laboratory mice ..............................................28

I
Table of Contents

Abstract .............................................................................................................................29
Protocol .............................................................................................................................30
Pre-operative considerations .............................................................................................30
Mice: housing requirements, general condition and health monitoring ...........................30
Hair clipping at one day prior to surgery .........................................................................31
Implantation ......................................................................................................................31
Operating environment, preparation of the telemetric transmitter ...................................31
Anesthesia .....................................................................................................................32
Surgery ..........................................................................................................................32
Post-operative care ...........................................................................................................33
Data acquisition .................................................................................................................34
Representative Results .....................................................................................................35
Tables and Figures: titles and legends ...........................................................................35
Discussion .........................................................................................................................41
Acknowledgments: ............................................................................................................42
Disclosures: ......................................................................................................................43
Chapter 3: Isoflurane and sevoflurane provide equally effective anesthesia in laboratory
mice .....................................................................................................................................44
Abstract .............................................................................................................................45
Introduction .......................................................................................................................45

II
Table of Contents

Materials and Methods ......................................................................................................47
Animals ..........................................................................................................................47
Preliminary transmitter implantation ...............................................................................48
Experimental setting ......................................................................................................48
Determination of minimum alveolar concentration ..........................................................49
Anesthesia experiments .................................................................................................50
Telemetric data acquisition and analysis ........................................................................50
Changes in body weight, and food and water intake ......................................................51
Acid-base balance and blood gas concentration ............................................................52
Statistical analysis ..........................................................................................................52
Results ..............................................................................................................................53
Minimum alveolar concentration .....................................................................................53
Acute effects of anesthesia ............................................................................................53
Post-anesthetic effects ...................................................................................................53
Discussion .........................................................................................................................58
Acknowledgement .............................................................................................................61
Chapter 4: Combining sevoflurane anesthesia with fentanyl-midazolam or s-ketamine in
laboratory mice .....................................................................................................................62
Abstract .............................................................................................................................63
Introduction .......................................................................................................................63

III
Table of Contents

Materials and Methods ......................................................................................................66
Animals and housing conditions .....................................................................................66
Transmitter implantation .................................................................................................67
Experimental setting ......................................................................................................67
Premedications ..............................................................................................................68
Determination of minimum alveolar concentration ..........................................................68
Anesthesia experiments .................................................................................................69
Telemetric data acquisition and analysis ........................................................................70
Changes in body weight .................................................................................................71
Acid-base balance and blood gas concentration ............................................................71
Statistical analysis ..........................................................................................................72
Results ..............................................................................................................................73
Minimum alveolar concentration .....................................................................................73
Induction of anesthesia ..................................................................................................74
Effects during anesthesia ...............................................................................................75
Effects during the first 3 days after anesthesia ...............................................................76
Discussion .........................................................................................................................79
Acknowledgments ..........................................................................................................84
Chapter 5: Impact of inhalation anesthesia, surgery and analgesic treatment on home cage
behavior in laboratory mice ..................................................................................................85

IV
Table of Contents

Abstract .............................................................................................................................86
Introduction .......................................................................................................................87
Materials and Methods ......................................................................................................88
Ethics statement ............................................................................................................88
Animals ..........................................................................................................................88
Experimental groups ......................................................................................................89
Experimental treatments and data recording ..................................................................89
Behavioral analysis ........................................................................................................90
Statistical analysis ..........................................................................................................90
Results ..............................................................................................................................91
Effects of treatment on analyzed behaviors: total 18-hour ..............................................93
Observations ..................................................................................................................93
Effects of treatment on analyzed behaviors: 6-hour observations ..................................93
Discussion .........................................................................................................................96
Conclusion ........................................................................................................................99
Acknowledgements ........................................................................................................99
Chapter 6: General Discussion ........................................................................................... 100
Chapter 7: References ....................................................................................................... 107
Appendix 1 ......................................................................................................................... 128
Acknowledgments .............................................................................................................. 130

V
List of Tables and Figures
List of Tables and Figures
Chapter 1
Figure 1.1) Structural formula of isoflurane
Figure 1.2) Structural formula of sevoflurane
Figure 1.3) Schematic drawing of DSI ETA F-20 implantable transmitter
Figure 1.4) Schematic drawing of the DSI telemetry acquisition system
Chapter 2
Table 2.1) General condition and health monitoring data sheet (Apendix 1)
Figure 2.1) Schedule for establishing telemetric-transmitter-bearing mice
Figure 2.2) Radiograph/sketch showing location of the implanted telemetry
transmitter.
Figure 2.3) Biopotential curves. Raw printout of one-lead ECG curves from a
conscious mouse and of the same animal under inhalation anesthesia
Figure 2.4) Raw data from long-term measurements in healthy and diseased mice
Figure 2.5) Example of presentation of results from long-term telemetry measurements
after an experiment
Chapter 3
Figure 3.1) Heart rate, core body temperature and respiration rate during 50 min of
anesthesia with isoflurane or sevoflurane

VI
List of Tables and Figures
Figure 3.2) Acid–base balance (pH), partial pressure of carbon dioxide ( pCO2) and
standard bicarbonate (HCO3) in arterial blood at 10, 30 and 50 min of
anesthesia.
Figure 3.3) Post-anesthetic measurements of the impact of isoflurane and sevoflurane on
heart rate, core body temperature and locomotor activity.
Chapter 4
Figure 4.1) Chamber for induction and system for maintenance of sevoflurane inhalation
anesthesia.
Figure 4.2) (A) Mean minimum alveolar concentrations for sevoflurane in adult C57BL/6J
female mice. (B) The mean time required until immobilization after mice were
placed in the sevoflurane-filled induction chamber
Table 4.1) Behaviors of mice during induction of anesthesia with sevoflurane.
Figure 4.3) Mean heart rate, core body temperature, and respiratory rate after
premedication in the home cage, in the induction chamber, and during 50-min
sevoflurane anesthesia
Figure 4.4) Mean acid–base balance (pH), pCO2, and pO2 in arterial blood after 10, 30,
and 50 min of anesthesia
Figure 4.5) Mean postanesthetic measurements of the effects of 3 anesthesia protocols
on heart rate and core body temperature
Chapter 5
Table 5.1) Ethogram of home cage behaviors
Figure 5.1) Scatter plot of discriminant scores assigned to individual mice.
Figure 5.2) Effects of anesthesia and surgery with or without analgesic treatment on
duration of 3 spontaneous home-cage behaviors compared to control values

VII
List of Abbreviations
List of Abbreviations
°C degrees Centigrade
A anesthesia only group
AALAS American Association for Laboratory Animal Science
ACT activity (as measured by telemetry system)
ANOVA analysis of variance
BT body temperature
bpm beats per minute
C control group
cc cubic centimeter
cm centimeter
CNS central nervous system
d day
DSI Data Sciences International
ECG electrocardiogram
ECLAM European College of Laboratory Animal Medicine
ED50 median effective dose
ESLAV European Society for Laboratory Animal Veterinarians

VIII