Pharmacokinetics of Inhalational Agents -
Anesthesia Pharm EXAM 1 UPDATED
ACTUAL Exam Questions and
CORRECT Answers
What describes the uptake (absorption) of inhalation agents from alveoli into systemic
circulation - CORRECT ANSWER - Pharmacokinetics
- Distribution into the body
- Metabolism primarily the liver
- Elimination primarily via the lungs
Volatile agents are delivered from a vaporizer that is calibrated in _______ - CORRECT
ANSWER - Percent or Fraction Delivered (FD)
Steps of getting the Inhalation agent to the pt - CORRECT ANSWER - 1. Vapor is picked up
by the FGF & delivered to the breathing circuit
2. Gas then enters the inspiratory limb of the circuit to be inspired by the patient (FI)
3. Inspired concentration is then taken into the lungs and transferred to the alveoli (FA)
4. Gas must then cross the pulmonary and vascular membranes (alveoli and capillary) to dissolve
in the blood
Inspired concentration in alveoli & in the blood is referred to as ____ - CORRECT
ANSWER - mmHg
,Concentration of agent is directly proportional to the ______ exerted - CORRECT
ANSWER - Partial Pressure
Partial Pressures (4) - CORRECT ANSWER - • Alveolar Partial pressure PA
• Inhaled partial pressure PI
• Brain partial pressure Pbr
• Arterial Partial pressure Pa
Blood:gas Partition Coefficient:
Agents w/ a low blood: gas partition coefficient equilibrate *(faster or slower?)* than high blood:
gas partition coefficient if all other variables are the same - CORRECT ANSWER - Faster
Des = 0.42
N2O = 0.47
Sevo = 0.65
Iso = 1.4
Halothane = 2.4
What does the blood: gas PC determine - CORRECT ANSWER - Rate of equilibration b/w
the blood & gas phase
Expired vs inspired concentrations are measured using _______ - CORRECT ANSWER -
Mass Spectrometry
, *T/F* The rate of equilibration of the FA toward the initial FI is used to evaluate equilibration of
the agents b/w blood & gas phases - CORRECT ANSWER - TRUE - this is the FA/FI ratio
The variables involved in the uptake of inhaled anesthetics include ________ (3) - CORRECT
ANSWER - CO
Concentration Gradient (PA/Pa)
Blood: Gas Solubility
Any increase of the variables involved in the uptake of inhaled anesthetics will do what to the
uptake? - CORRECT ANSWER - Increase uptake
Variables: CO, concentration gradient (PA/Pa) & Blood: gas solubility
Increased uptake will do what to the rise in Pa (?) - CORRECT ANSWER - Slow the rise
Where in the circuit does dead-space begin - CORRECT ANSWER - Y piece
FGF is determined by what 2 things - CORRECT ANSWER - Vaporizer & Flowmeter settings
FI (inspired gas concentration) is determined by what 3 things - CORRECT ANSWER - FGF
rate
Breathing-Circuit Volume
Circuit Absorption
*** *Inhalation agents chart...* - CORRECT ANSWER - *Pg 13 !!!!*
Anesthesia Pharm EXAM 1 UPDATED
ACTUAL Exam Questions and
CORRECT Answers
What describes the uptake (absorption) of inhalation agents from alveoli into systemic
circulation - CORRECT ANSWER - Pharmacokinetics
- Distribution into the body
- Metabolism primarily the liver
- Elimination primarily via the lungs
Volatile agents are delivered from a vaporizer that is calibrated in _______ - CORRECT
ANSWER - Percent or Fraction Delivered (FD)
Steps of getting the Inhalation agent to the pt - CORRECT ANSWER - 1. Vapor is picked up
by the FGF & delivered to the breathing circuit
2. Gas then enters the inspiratory limb of the circuit to be inspired by the patient (FI)
3. Inspired concentration is then taken into the lungs and transferred to the alveoli (FA)
4. Gas must then cross the pulmonary and vascular membranes (alveoli and capillary) to dissolve
in the blood
Inspired concentration in alveoli & in the blood is referred to as ____ - CORRECT
ANSWER - mmHg
,Concentration of agent is directly proportional to the ______ exerted - CORRECT
ANSWER - Partial Pressure
Partial Pressures (4) - CORRECT ANSWER - • Alveolar Partial pressure PA
• Inhaled partial pressure PI
• Brain partial pressure Pbr
• Arterial Partial pressure Pa
Blood:gas Partition Coefficient:
Agents w/ a low blood: gas partition coefficient equilibrate *(faster or slower?)* than high blood:
gas partition coefficient if all other variables are the same - CORRECT ANSWER - Faster
Des = 0.42
N2O = 0.47
Sevo = 0.65
Iso = 1.4
Halothane = 2.4
What does the blood: gas PC determine - CORRECT ANSWER - Rate of equilibration b/w
the blood & gas phase
Expired vs inspired concentrations are measured using _______ - CORRECT ANSWER -
Mass Spectrometry
, *T/F* The rate of equilibration of the FA toward the initial FI is used to evaluate equilibration of
the agents b/w blood & gas phases - CORRECT ANSWER - TRUE - this is the FA/FI ratio
The variables involved in the uptake of inhaled anesthetics include ________ (3) - CORRECT
ANSWER - CO
Concentration Gradient (PA/Pa)
Blood: Gas Solubility
Any increase of the variables involved in the uptake of inhaled anesthetics will do what to the
uptake? - CORRECT ANSWER - Increase uptake
Variables: CO, concentration gradient (PA/Pa) & Blood: gas solubility
Increased uptake will do what to the rise in Pa (?) - CORRECT ANSWER - Slow the rise
Where in the circuit does dead-space begin - CORRECT ANSWER - Y piece
FGF is determined by what 2 things - CORRECT ANSWER - Vaporizer & Flowmeter settings
FI (inspired gas concentration) is determined by what 3 things - CORRECT ANSWER - FGF
rate
Breathing-Circuit Volume
Circuit Absorption
*** *Inhalation agents chart...* - CORRECT ANSWER - *Pg 13 !!!!*
