1)     ALFAXALONE - coming soon

a)      In the mean time see our alfaxalone review

3)     DIAZEPAM & a pure mu agonist Opioid

i)                   General Description

(1)   A benzodiazepine and fentanyl, hydromorphone, methadone, morphine, or oxymorphone

ii)                 Patient selection

(1)   Recommended use

(a)    Debilitated canine patients

(i)      Primarily if inhalant agents are not well tolerated (especially if blood pressure is difficult to maintain on inhalant agents)

(2)   Cautionary information

(a)    This technique is not familiar to most veterinarians. Initial familiarization should involve the application of this method to healthy, routine cases under careful supervision.

(i)      Routine patients must be very sedate from their preanesthetic medications in order to consider them eligible for this protocol

(b)   Surgical anesthetic levels are not realistically achievable in feline patients

iii)               Dosage

(1)   Intermittent bolus technique

(a)    Diazepam @ 0.05 mg/lb every 40 to 60 minutes

(b)   Add one of the following opioids every 20 to 30 minutes

(i)      Hydromorphone            0.04 mg/kg (0.02 mg/lb)

(ii)    Oxymorphone             0.02 mg/kg (0.01 mg/lb)

(2)   CRI (TIVA) technique

(a)    TBC

iv)               Cautionary Notes

(1)   Watch for bradycardia and respiratory depression

v)                 General Cost Category

(1)   Moderately low with hydromorphone

(2)   Moderately high with oxymorphone

3)     HALOTHANE

a)      General Description

i)                    A volatile halogenated liquid of moderately low solubility that undergoes significant metabolism by the liver

ii)                 Halothane is not available in North America at this time

b)      Patient selection

i)                    Recommended use

(1)   This anesthetic agent is suitable for use with most veterinary patients

(2)   It is an alternative for those patients that demonstrate a poor tolerance for isoflurane or sevoflurane

(3)   The bronchodilatory effect of halothane may make it attractive for selected patients with respiratory disease

ii)                  Cautionary information

(1)   As with any inhalant anesthetic, cardiac and respiratory depression result as anesthetic concentrations are increased

(2)   Chronic exposure has been associated with anesthetic personnel developing liver concerns

(3)   Avoid Halothane when intracranial disease is suspected

(a)    Halothane can raise intracranial pressures

c)      Dosage

i)                    Routine use

(1)   Completing induction following injectable agent

(a)    Initiate flow rates of 1.0 to 1.5 liter per minute at 2.5 % - 4.0 %

(i)      Reduce percentage as indicated by patients response

(2)   Maintenance

(a)    Once stable, reduce oxygen flow to 500 ml to 1 liter per minute

(i)      The reservoir bag must remain moderately full

1.      If not, the flow rate must be increased and the machine must be examined for leaks at the earliest possible convenience

(b)   Remember that prior to surgical stimulation, a patient may appear adequately anesthetized only to show a dramatic response to stimulation

(i)      An experienced anesthetist should be able to anticipate and minimize this event

(ii)    A 0.002 mg/kg (0.001 mg/lb) fentanyl bolus IV at initiation of surgery may help to stabilize a patient that is on the light side

(c)    Effective analgesic & sedative premedicants will significantly reduce the level of inhalant agent necessary for maintenance of a surgical plane of anesthesia

d)      General Cost Category

i)                    Low

4)     ISOFLURANE

a)      General Description

i)                    A volatile liquid of low solubility that is minimally metabolized by the liver

b)      Patient selection

i)                    Recommended use

(1)   This anesthetic agent is suitable for use with most veterinary patients

ii)                  Cautionary information

(1)   As with any inhalant anesthetic, cardiac and respiratory depression result as anesthetic concentrations are increased

(a)    Not all patients under Isoflurane will be able to maintain adequate blood pressures

(b)   Switching to an alternative maintenance agent may be necessary

(2)   Although isoflurane is considered the safest agent as pertains to staff exposure, we should all strive to minimize our exposure to this or any other inhalant agent

c)      Dosage

i)                    Routine use

(1)   Completing induction following injectable agent

(a)    Initiate flow rates of 1 to 1.5 liter per minute at 3.5 % - 5.0 %

(i)      Reduce vaporizer setting as indicated by patients response

(2)   Maintenance

(a)    Once stable, reduce oxygen flow to 500 ml or 1 liter per minute

(i)      The reservoir bag must remain full

1.      If not, the flow rate must be increased and the machine must be examined for leaks at the earliest possible convenience

(b)   Remember that prior to surgical stimulation, a patient may appear adequately anesthetized only to show a dramatic response to stimulation

(i)      An experienced anesthetist should be able to anticipate and minimize this event

(ii)    A 0.002 mg/kg (0.001 mg/lb) fentanyl bolus IV at initiation of surgery may help to stabilize a patient that is on the light side

(c)    Effective analgesic & sedative premedicants will significantly reduce the level of inhalant agent necessary for maintenance of a surgical plane of anesthesia

d)      General Cost Category

i)                    Moderately low

5)     PROPOFOL

a)      General Description

i)                    Propofol is an alkylphenol derivative suspended in a hyperlipid emulsion

b)      Patient selection

i)                    Recommended use

(1)   Canine cases when:

(a)    Tracheal intubation is not possible

(i)      Bronchoscopy

(b)   An anesthetic machine cannot be used

(i)      MRI studies as a constant rate infusion via a plastic drip set

(c)    Isoflurane/Sevoflurane is not well tolerated

(2)   Appropriate for sighthounds

(3)   Appetite appears increased in many patients for a short period of time after recovery from propofol

(a)    This would be an advantage when dealing with diabetic patients where an early return to their normal routine is desired

ii)                  Cautionary Notes

(1)   Hyperlipid emulsion easily promotes bacterial growth

(a)    Once opened, nonpreservative product should be used within 6 to 12 hours

(2)   Feline patients do not clear phenols well 1,2,3,4

(a)    Subsequent boluses or ongoing CRI doses should be adjusted downward over time

(b)   Recovery will be more prolonged than with dogs

c)      Dosage

i)                    Routine maintenance

(1)   Dogs

(a)    Boluses of ¼ to 1/3 of the original induction dose as needed

(b)   CRI at 0.05 to 0.4 mg/kg/minute (0.025 to 0.2 mg/lb/minute)

(i)      If too light, give 0.5 to 1.0 mg/kg (0.25 to 0.5 mg/lb) IV then increase CRI rate by 25%

(ii)    If too deep, stop propofol until suitable anesthetic level is reached, then reinitiate CRI at 25% lower rate

(2)   Cats 1,2,3,4

(a)    Boluses of ¼ to 1/3 of the original induction dose as needed

(b)   CRI at 0.05 to 0.2 mg/kg/minute (0.025 to 0.1 mg/lb/minute)

(i)      If too light, give 0.5 mg/kg (0.25 mg/lb) IV then increase CRI rate by 25%

(ii)    If too deep, stop propofol until suitable anesthetic level is reached, then reinitiate CRI at 25% lower rate

(iii)   Feline patients do not clear phenols well, repetitive day to day use not recommended

(c)    Subsequent boluses or ongoing CRI doses should be adjusted downward over time

(d)   Recovery will be more prolonged than with dogs

d)      General Cost Category

i)                    Moderate

1 The effects of consecutive day propofol anesthesia on feline red blood cells. Andress JL, Day TK, Day D. Vet Surg. 1995 May-Jun;24(3):277-82.

2 Repetitive propofol administration in dogs and cats. Matthews NS, Brown RM, Barling KS, Lovering SL, Herrig BW. J Am Anim Hosp Assoc. 2004 Jul - Aug;40(4):255-60.

3 The effect of the duration of propofol administration on recovery from anesthesia in cats. Pascoe PJ, Ilkiw JE, Frischmeyer KJ. Vet Anaesth Analg. 2006 Jan;33(1):2-7.

4 Clinical assessment of repeated propofol-associated anesthesia in cats. Bley CR, Roos M, Price J, Ruess-Melzer K, Buchholz J, Poirier V, Kaser-Hotz B. J Am Vet Med Assoc. 2007 Nov 1;231(9):1347-53.

6)     SEVOFLURANE

i)                   General Description

(1)   A volatile liquid of low solubility that is minimally metabolized by the liver

(a)    Liver metabolism exceeds that of Isoflurane

ii)                 Patient selection

(1)   Recommended use

(a)    This anesthetic agent is suitable for use with most veterinary patients

(b)   With the exception of patients experiencing extreme respiratory compromise sevoflurane is rarely of any advantage over isoflurane

(2)   Cautionary information

(a)    As with any inhalant anesthetic, cardiac and respiratory depression result as anesthetic concentrations are increased

(i)      Not all patients under Sevoflurane will be able to maintain adequate blood pressures

(ii)    Switching to an alternative maintenance agent may be necessary

(b)   Although sevoflurane is considered a relatively safe agent as pertains to staff exposure, we should all strive to minimize our exposure to this or any other inhalant agent

iii)               Dosage

(1)   Routine use

(a)    Completing induction following injectable agent

(i)      Initiate flow rates of 1.0 to 1.5 liter per minute at 5 % - 7.0 %

1.      Reduce percentage as indicated by patients response

(b)   Maintenance

(i)      Once stable, reduce oxygen flow to 500 ml or 1 liter per minute

1.      The reservoir bag must remain full

2.      If not, the flow rate must be increased and the machine must be examined for leaks at the earliest possible convenience

(ii)    Remember that prior to surgical stimulation, a patient may appear adequately anesthetized only to show a dramatic response to stimulation

1.      An experienced anesthetist should be able to anticipate and minimize this event

2.      A 0.002 mg/kg (0.001 mg/lb) fentanyl bolus IV at initiation of surgery may help to stabilize a patient that is on the light side

3.      Effective analgesic & sedative premedicants will significantly reduce the level of inhalant agent necessary for maintenance of a surgical plane of anesthesia

iv)               General Cost Category

(1)   Moderately high