Induction Agents and Adjuvants (Mod 3) Flashcards
What is the MAC of Isoflurane?
0.0115 atm (low)
What is the B/G coefficient of Isoflurane
1.4 (Large)
What are common and adverse effects of Isoflurane?
Could depress CV (affects the myocardium) and the respiratory depression
- could lead to arrhythmias
Is isoflurane dose dependant?
Yes; it has a high potency (low MAC) with low solubility (large b/G)
Contraindications for Isoflurane?
susceptibility to malignant hyperthermia
What is the relative potency and solubity of Sevoflurane?
High potency (low Mac) and low solubility (high b/g coefficient)
What can Sevoflurane be used as?
A potent bronchodilator; has been used in treatment of status asthmatics
- Can be used for Asthma
- Sweet smell and well tolerated for inhalation induction
Complications with Sevoflurane
Sevoflurane degrades into toxic compounds in the presence of a carbon dioxide absorber. Can cause nephrotoxitiy
- causing CV and resp depression (and arrhythmias)
- **Renal Toxicity)
Desflurane relative potency and solubility?
Moderate potency (MAC 0.06 atm mod) and low b/g coefficient (0.45)
Why is Desflruane a poor induction agent?
Pungency irritates the airway; increases risk of cough and laryngospasm
Which anesthetic gas has a similar induction time as nitrous oxide?
Desflurane; much more potent though (oil/gas partition coefficient is higher)
What occurs with increased/rapidly high concentration of anesthetics? -> think Desflurane
edit
Causes marked activation of the sympathetic nervous system
Relative potency and solubility of Nitrious Oxide?
Low potency (High MAC:1.04) and low b/g coefficient (b/g = 0.47)
Why is Nitrous oxide paired with other anesthetic agents?
Low potency means the need to maintain a acceptable partial pressure of O2 prevents the attainment of full anesthesia
- Can provide a analgesic effect in combo with other agents
- 2nd gas effect?
What are some adverse effects and considerations for Nitrous Oxide?
2nd gas effect; diffusion hypoxia aka cana displaces other gases
- Can cause expansion of air collections (pneumothorax, bowel obstruction, obstructed middle ear, intracranial air)
Which anesthetic gas does not require a vaporizer?
Nitrous oxide, it mixes in with regular O2
What is Thiopental?
Barbiturate; ultra short acting; can induce anesthesia in seconds; BUT no reversal agent
Dose for Thiopental?
3-4 mg/kg IV
What are indications for Thiopental aside from
Reduction in elevated ICP (cerebral vasoconstriction) and seizures (increases the threshold for action potneitals in teh brain)
General doses for IV anesthetics?
3-4 mg/kg IV
Risk factor with Thiopental (barb)
Laryngospasm or Bronchospasm may occur with induction of light anesthesia and with airway manipulation (intubation).
- potent short acting drug with no reversal agent. subbed out with propofol
- indicated for elevated ICP or seizures, but benzos are preferred if available
Why is Propofol preferred to short acting barbiturates?
Ultra short acting; rapidly metabolized, meaning faster recovery than barbiturates
What is Propofol used for?
Induction and maintenance (sedation for mech. ventilation)
Why could Propofol be a source of infection?
It’s a intralipid preparation; side note, its also a large caloric source