Flashcards in Anaesthesia Deck (120)
Nelissen P, Corletto F, Aprea F, White RAS. Effect of Three Anesthetic Induction Protocols on Laryngeal Motion during Laryngoscopy in Normal Cats. Vet Surg. 2012 Oct;41(7):876–83.
- from intro: in dogs, thiopental is best, but propofol good too
- this study: no difference between alfaxolone, propofol, ket + midazolam
- 6 cats had no movement even though they were normal cats
- (all were premedicated with methadone, Doxapram was not used)
Baetge CL, Matthews NS. Anesthesia and analgesia for geriatric veterinary patients. Vet. Clin. North Am. Small Anim. Pract. 2012 Jul;42(4):643–53–v.
- 30 % of geriatric patients have undiagnosed subclinical disease
Kelly CK, Hodgson DS, McMurphy RM. Effect of anesthetic breathing circuit type on thermal loss in cats during inhalation anesthesia for ovariohysterectomy. J Am Vet Med Assoc. 2012 Jun 1;240(11):1296–9.
- Bain circuit vs a novel mini-rebreathing circuit on temperature in cats
- no difference in temperature (probably would have been a difference in humidity)
- duration of procedure more influential on thermal loss than type of circuit
Zacuto AC, Marks SL, Osborn J, Douthitt KL, Hollingshead KL, Hayashi K, et al. The influence of esomeprazole and cisapride on gastroesophageal reflux during anesthesia in dogs. J Vet Intern Med. 2012 May;26(3):518–25.
- placebo vs esomeprazole vs esomeprazole + cisapride
- results: esomeprazole + cisapride DID reduce # of reflux events and raised pH
- protocol: esomeprazole 1mg/kg IV & cisapride 1mg/kg IV
- 12-18 hrs preop and again 1-1.5 hrs preop
- esomeprazole alone didn’t reduce # of events but it raised pH to non-acid levels
Conner BJ, Hanel RM, Hansen BD, Motsinger-Reif AA, Asakawa M, Swanson CR. Effects of acepromazine maleate on platelet function assessed by use of adenosine diphosphate activated- and arachidonic acid- activated modified thromboelastography in healthy dogs. Am J Vet Res. 2012 May;73(5):595–601.
- intro: previous reports suggest that acepromazine may alter platelet function
- no altered platelet function in dogs getting 0.1 mg/kg or 0.05 mg/kg IV
McSweeney PM, Martin DD, Ramsey DS, McKusick BC. Clinical efficacy and safety of dexmedetomidine used as a preanesthetic prior to general anesthesia in cats. J Am Vet Med Assoc. 2012 Feb 15;240(4):404–12.
- dexmedetomidine was a great preanesthetic for cats compared to no preanesthetic
- 40 mcg/kg IM!
- improved intubation, decreased amount of propofol for induction, decreased amount of iso needed for maintenance, better pain scores after procedure
- decreased heart rate, pale mucous membranes, emesis occurred more often
Escobar A, Pypendop BH, Siao KT, Stanley SD, Ilkiw JE. Pharmacokinetics of dexmedetomidine administered intravenously in isoflurane-anesthetized cats. Am J Vet Res. 2012 Feb;73(2):285–9.
10 mcg/kg given IV over 5 minutes had a T1/2 of 3.3 hours
Franklin MA, Rochat MC, Payton ME, Broaddus KD, Bartels KE. Comparison of three intraoperative patient warming systems. J Am Anim Hosp Assoc. 2012 Jan;48(1):18–24.
- once in the OR, Bair Hugger vs Bair Hugger + water blanket vs warming panels
- once in the OR, all 3 groups maintained temp equally
- the warming panels were as effective as Bair huggers at maintaining temp
- none were able to regain the lost heat from surgical prep
In general, drugs that are more lipid soluble take longer/less time to achieve a steady state concentration with CRI’s or multiple dosing
From the perspective of general anesthetic action, the organs and tissues of the body may be divided into three groups, categorized by how quickly drugs distribute to them after an IV injection. What are the three groups?
vessel-rich group (brain, heart, kidneys)
vessel-poor group (fat)
Most vaporizers used in small animal anesthesia today are:
in-circuit / out-of-circuit
variable-bypass / measured flow
flow-over / bubble-through / injection- type
temperature compensated / not temperature compensated
not agent specific / agent specific
out of circuit, variable-bypass, flow-over, temperature compensated, agent specific
If an incorrect agent is used in an agent-specific vaporizer (e.g. you put isoflurane in a sevoflurane vaporizer), what might happen?
the vaporizer might have an unpredictable output
What makes a desflurane vaporizer unique?
- it is warmed to allow the desflurane to become a gas
- it is an injection-type vaporizer
- it needs to be plugged into a power source
- it has a special refilling mechanism to ensure a tight seal btwn bottle and vaporizer
What does the capnograph of a patient re-breathing CO2 look like?
It does not drop back to 0
In a rebreathing system, what will happen if the inspiratory valve becomes stuck open? What will happen if the expiratory valve becomes stuck open?
-Inspiratory valve open: the patient will rebreathe exhaled gas with CO2
-Expiratory valve open: the patient will rebreathe exhaled gas with CO2
When using a rebreathing circuit, do we usually use the system as a “closed” circuit or a semi-closed circuit?
What is the weight cut-off for using a rebreathing vs a non-rebreathing system?
Equation for Minute volume (MV)
RR x TV
What is the recommended fresh gas flow rate for a nonrebreathing system?
At least 3 times the patient’s respiratory minute volume
Ko JC, Austin BR, Barletta M, Weil AB, Krimins RA, Payton ME. Evaluation of dexmedetomidine and ketamine in combination with various opioids as injectable anesthetic combinations for castration in cats. J Am Vet Med Assoc. 2011 Dec 1;239(11):1453–62.
- playing with different kitty magic cocktails
- all cats got dexmedetomidine (25 ucg/kg) + ketamine (3 mg/kg) with either:
- buprenorphine, butorphanol, or hydro
- results: DKBut and DKH were good cocktails to do a neuter. DKBup not quite enough sedation by 10 min
Fresh gas flows around ________ ml/kg are required to prevent rebreathing in most nonrebreathing systems.
200 – 500 ml/kg
In a rebreathing system, the concentration of inhalant the patient inspires will be less than that dialed on the vaporizer. In a nonrebeathing system, the concentration of inhalant the patient inspires will be the same as that dialed on the vaporizer T/F?
Name the color code and cylinder type that is found in for each of the following gasses color-coded (North American color coding):
Nitrous oxide, carbon dioxide, nitrogen, oxygen, medical air
Blue and E: Nitrous oxide
Gray and E: Carbon dioxide
Black and H: Nitrogen
Green and E or H: Oxygen
Yellow and E: Medical air
If a tank of oxygen has half of the pressure than it did when it was full, then what percentage of oxygen volume is left in the tank?
When reading the flow rate on a flowmeter with a bobbin, you should read the top/middle/bottom of the bobbin. When reading the flow rate on a flowmeter with a ball, you should read the top/middle/bottom of the ball.
Why shouldn’t the oxygen flush valve be used while an anesthetized patient is on a nonrebreathing system? Why shouldn’t the oxygen flush valve be used while an anesthetized patient is on a rebreathing system?
-nonrebreathing: barotrauma from the high flow rate
-rebreathing: the oxygen will dilute the gas anesthetic and alter the plane of anesthesia
How does MAC relate to the body (According to Tobias - the basis for MAC values)
End-tidal concentration (concentration in alveoli at end of expiration) of inhalant is considered to be equal to the concentration of inhalant in the brain at equilibrium
Name two ways to scavenge inhalant anesthetics
active and passive scavenging
What gas cannot be scavenged with the passive charcoal-container scavenging?