1. Michael Lovasz, DVM, MS VCA Northwest Veterinary Specialists
It’s just sedation……
Michael Lovasz, DVM, MS
VCA Northwest Veterinary Specialists

2. Quick bit of Housekeeping

3. Pre-Anesthetic Considerations
History
Diagnostics
PE Findings
ASA Status

4. ASA Classification
American society of anesthesiologists physical class status I-V
Useful for determining appropriate drug protocol
Prepare for additional monitoring i.e. arterial catheter
Prepare for additional catheter placement, blood pressure support, transfusion expectations
Greater ASA status = Greater anesthetic risk

5. ASA Classification ASA I: Normal, healthy patient
No disease noted on physical examination
Sx candidates include: Routine castration, ovariohysterectomy

6. ASA Classification ASA II: Mild systemic disease:
Heart murmur with compensated disease
Fracture without shock
Uncomplicated hernia
Localized skin tumor

7. ASA Classification ASA III: Severe systemic disease: Fever Anemia
Dehydration
Hypovolemia
Azotemia

8. ASA Classification ASA IV:
Severe systemic disease that is life threatening:
Uremia
Toxemia
Severe dehydration and hypovolemia
Severe anemia
High fever

9. ASA Classification ASA V:
Moribund; not expected to live 1 day with or without surgery
E: Emergency procedure
Can accompany any ASA classification

10. Vitals Minimal data base PE: Temperature, heart rate, respiratory rate
Minimal data base GA: PE, PCV/TS, full blood work, ECG, BP, +/- further diagnostics

11. Definitions Sedation: A state of central depression with drowsiness
Unaware of surroundings, RESPONSIVE to painful stimuli
Dexmedetomidine

12. Definitions Tranquilization: Behavioral change, anxiety is relieved
Patient aware of surroundings
Indifferent to minor pain
Acepromazine, Diazepam, Midazolam

13. Definitions Narcosis: drug-induced state of deep sleep
Patient cannot be easily aroused
Analgesia may not be included

14. Definitions Hypnosis: A condition of artificially induced trance
Moderate CNS depression
Patient easily aroused

15. Pre-anesthetic sheet

16. Anesthesia Plan

17. Anesthesia Sheet

18. Anesthesia Sheet

19. Emergency Drug Sheet

20. Risk of Death
The risk of death: Confidential Enquiry into Perioperative Small Animal Fatalities. Brodbelt D, Blissett K, Hammond R, et. al. Vet Anaesth Analg, 2008; 35:
Postoperative deaths: 47% dogs, 61% cats

21. Monitoring: Vigilance

22. Monitoring: Vigilance
Eye position
Mucous membrane
Chest excursions/bag movement
Blood loss

23. Monitoring: Recommendations
AAHA Anesthesia Guidelines for Dogs and Cats. Bednarski R, Grimm K, Harvey R, et. al. J AM Anim Hosp Assoc 2011; 47:

24. Monitoring: Recommendations
HR, RR, Temp, BP, ECG
Pre-anesthetic evaluation
Drug and equipment selection
Monitor vitals at least every 5 minutes

25. Monitoring
Patients must be monitored regularly until regular vitals and behavior have returned
Critical period of time: respiratory arrest, cardiac arrest, excitation, depression, hypothermia
Greater ASA status = Greater risk all stages

26. Monitoring All periods of care must be monitored Pre-anesthesia
Recovery

27. Monitoring Keep it between the lines Do not ignore abnormal
Use your senses: eyes, ears, touch, smell, and mouth (speak up!)

28. Case #1

29. Case #1 1yr MI Labrador Retriever Hind Limb Radiographs
High energy dog

30. More Info PE unremarkable EKG normal (motion artifact)
Patient resents restraint on table

31. More Info Dexmedetomidine 3mcg/kg IV Butorphanol 0.2mg/kg IV
Flow by oxygen, non-invasive BP, ECG

32. Case #1 Patient develops second degree AV block
Heart rate mid 50s, systolic blood pressure 130mmHg
Radiographs deemed acceptable
Recovered on floor flow by oxygen, ECG

33. Case #1 Atipamezole administered 0.1mg/kg IM
Second degree AV block resolved
Patient returned to pre-examination level of consciousness

34. Case #2

35. Case #2 14 yr old FS Toy Poodle
Abdominal Ultrasound/Suspect Urinary bladder stones
Calm dog, does not like restraint on back

36. More Info Azotemic III/VI murmur
Owners Decline Work-up with cardiologist

37. Case #2 IV catheter placed without sedation Midazolam 0.2mg/kg IV
Butorphanol 0.2mg/kg IV
Multiple bladder stones surgery recommended

38. Case #2 Cardiologist evaluates Recommends “Judicious use of fluids”
Avoid alpha 2 agonists, ketamine
Keep vitals between the lines

39. Case #3

40. Case #3 5yr MC Rottweiler Eye mass/skin tag removal
Muzzle required for examination

41. More Info PE limited due to anxious/aggressive
Heart auscultation normal (limited)
Bloodwork NSF

42. More Info Maximum sedation: owner muzzled Dexmedetomidine 20mcg/kg IM
Ketamine 5mg/kg IM
Methadone 0.4mg/kg IM

43. More Info Mid procedure develops bradycardia 28 bpm
Second degree AV block
Treatment?

44. Case #3 Treated with 0.02mg/kg of atropine IV Arrhythmia intensified
Arrhythmia resolved
Patient recovered, still a jerk, no reversal administered

45. Case #4

46. Case #4 12yr fs DLH abdominal ultrasound IV/VI murmur
Cardiologists recommends avoiding alpha-2 agonists and ketamine

47. More Info
Mild azotemia
Pre-treated oral gabapentin
IV catheter placed

48. Case #4 Butorphanol 0.2mg/kg IV Alfaxalone 0.5mg/kg IV Flow by oxygen
Intubation equipment available

49. Case #4 Ultrasound performed without incident
Patient recovered with technician in quiet room

50. Take Home Less stress more success Do not ignore abnormal
If you can intubate, you should
Vigilance saves lives

51. Questions?