Dr. Marcel Perret-Gentil presents six simple-to-implement techniques to significantly improve surgical outcomes. You may feel proficient, even confident in performing rodent surgery; however, you may be surprised how simple improvements can have a huge impact to your animal’s recovery and data. The presentation is designed for individuals who have minimal or no rodent surgical skills but is also a great opportunity for those with considerable experience wanting to improve outcomes as well as teach such key principles. Key Topics Include: - Improve surgical outcomes that will lessen post-op morbidity and mortality - Improve data yield after rodent surgery - Implementation of key principles into a rodent surgical program

1. Copyright 2023. All Rights Reserved. Contact Presenter for Permission.
University Veterinarian & Director
Laboratory Animal Resources Center
The University of Texas at San Antonio (UTSA)
Marcel Perret-Gentil, DVM, MS
Simple Tips to
Significantly
Improve Rodent
Surgical Outcomes

2. 6 Simple Tips
that will Significantly Improve
Rodent Surgical Outcomes
University Veterinarian & Director
The University of Texas at San
Antonio
marcel.perret@utsa.edu
https://research.utsa.edu/complia
nce/larc/training.html
Marcel Perret-Gentil
President
PLAVS (Perret-Gentil Lab Animal
Veterinary Services)
mperret1@gmail.com
www.plavs.net

3. 3
Ms. Rita is 85
An exemplary nurse
Just a Little bit out of practice

4. The great tips
1. Acclimation
2. Aseptic technique – the ‘solo surgeon syndrome’
3. Temperature regulation
4. Hydration
5. Oxygen supplementation
6. Non-pharmaceutical methods of pain control

5. Tip 1 – Acclimation

6. Food
Lights
Sounds
Temperature
Bedding
Smells
Cage
6

7. The acclimated mouse
7

8. Tip 2 – Aseptic Surgery?

9. Survival alone not a valid
criterion for success
Success should be based on absence of
altered physiological function, immune
responses and behavioral changes
(Cunliffe-Beamer, 1993)
9

10. Aseptic technique increases success of ovarian transplants in
mice & speeds return to post-op normal (Cunliffe-Beamer 1972-73;
Cunliffe-Beamer 1990)
Contamination activates macrophages (Bancroft, Schreiber et al. 1989),
and leads to changes in cytokines & B cells levels (Abbas, Lichtman
et al. 1991)
SUBCLINICAL infections induce physiological changes (Committee
on Infectious Diseases of Laboratory Rats and Mice 1992)
Although NO CLINICAL SIGNS observed, experimentally
inoculated rats (108 S. aureus or P. aeruginosa) had significant
alterations in plasma fibrinogen, serum glucose, total white
blood cell counts, and wound histology scores (Bradfield, John et al.
1992)
10

11. Summary
• Delays to post-op normality
• Physiological changes
• Alterations in immunity
• Affects data yield
Poor rodent aseptic surgery results in:
11

12. A few easy tips on aseptic
technique
https://research.utsa.edu/compliance/larc/t
raining.html for many easy tips
12

13. Surgeon Prep
Impermeable arm sleeves
Misted with disinfectant
13

14. Crowded surgical area setup
Correct
setup
A bit
crowded
Suture touching non-
sterile area
👿
14
Gauze touching non-
sterile area

15. Easy Table & Animal Draping
Technique without Sterile Gloves
15

16. Post-op recovery cage is dirty
👿

17. Post-op recovery cage is clean, to
minimize post-op infections
😇

18. Rodent Surgical Draping
The 5 properties of the ideal rodent
draping material…
1. Sterile
2. Adheres to skin
3. Impermeable
4. Transparent
5. Traps body heat…
18
Bonus: Cheap!

19. Draping the Animal
✕
1. Sterile
2. Adheres to skin
3. Impermeable
4. Transparent
5. Traps body heat…
19
Cheap!
🙁

20. The Solo Surgeon
One person does everything
What happens if non-sterile items such as the
anesthesia dials, stereotaxic apparatus knobs, light
handles and microscope dials have to be manipulated
during surgery?
The next slides provide practical solutions to the “Solo
Surgeon” problem
20

21. Touching non-
sterile parts
with sterile
gloves
👿
👿
👿

22. Press’n Seal or aluminum foil
😇
😇
😇

23. 😇
😇
😇

24. Light handles

25. Surgical microscope

26. Need to use a timer and
you are the solo
surgeon?

27. When need to write
notes and you are the
solo surgeon

28. Tip 3 – Temperature
Regulation

29. Anesthetics & Hypothermia
• Anesthetics depress
thermoregulation
• Vasodilation makes it
worse
• Prolongs recovery
• Leads to
hypoventilation
• ¯ platelet function
• ­ risk of infection
• Bradycardia, fatal
arrhythmias, myocardial
infarction
• ­ blood viscosity = ¯
gas exchange
• ↑ mortality
• Affects data
29

30. Good Veterinary
Care Involves
Avoidance of
Hypothermia

31. Insulate with Press’n Seal
31
Include tail

32. Far Infrared
Heating
Somnosuite
Somnoflow

33. 33
https://research.utsa.edu/compliance/larc/training.html

34. Tip 4 - Hydration
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35. Hydration
Make it a habit of administering WARMED
fluids before surgery – Lactated Ringer’s
solution or onrmal saline
• Mice 0.5-1 ml SC/IP
• Rats 5-10 ml SC/IP
😇
35
10-20 ml/kg

36. Tip 5 – Oxygen
Supplementation
36

37. Injectable Anesthesia
= Hypoxia = O2 saturation in 80s & 70s (dose dependent)*
Not consistent with acceptable veterinary practice
Malpractice?
UTSA requires O2 supplementation
37
*Blevins et al, 2021

38. O2 Supplementation
O2 supplementation = ↑↑↑ Survival*
At UTSA - vaporizer system with anesthesia
turned off to supplement O2 (0.5 L/min)
via facemask when using injectable
anesthetics
May use O2 concentrators
38
*Blevins et al, 2021

39. Tip 6 – Non-Pharmacological
Methods of Pain Control
39

40. Treating the Mind
and Other Parts
Simkin & O’hara, 2002; Chia et al, 2017

42. Fear & Anxiety
Enhance Pain Response
Providing a stress-free environment should
be considered in the pain management
program
Linton 2000; Morley et al. 1999; Munro et al. 2007; Panksepp
1980; Perkins and Kehlet 2000; Ploghaus et al. 2001

43. Minimizing Environmental Stress
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Minimizes stress-induced hyperalgesia*
*Mogil, 2017

44. Tasty & Energy Dense
Supplementation
Bacon Softies
bio-Serv.com
DietGel
clearh2o.com 44

45. Social Housing
Single housing – The post op norm, however…
• Rats spinal cord injury – 20% less chance of
survival when housed individually
• Telemetric implant surgery, female mice -
When housed socially needed less time to fully
recover
(Van Loo et al., 2007)
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46. Soon!!
Overview of Refinements in Rodent
Surgical Practices (JAALAS)
46