Inhalation Anesthesia #1 Flashcards Preview

GNURS625 Pharmacology for Anesthesia 1 > Inhalation Anesthesia #1 > Flashcards

Flashcards in Inhalation Anesthesia #1 Deck (39)
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1
Q

2 true gases used in anesthesia

A

Nitrous and Oxygen

2
Q

Other inhaled agents, besides O2 and N2O are known as

A

Lipids, Vapors, or Volatile Liquids

3
Q

All gases are __________

A

non ionized and have low molecular weight and delivered to the blood via the lungs

4
Q

The goal of inhalation anesthesia is to produce the anesthetic state by creating a specific concentration (MAC) of anesthesia molecules in the __________. This si done by establishing a _________ of an agent in the lungs, which then equilibrates with the brain and spinal cord.

A

central nervous system

partial pressure

5
Q

FI (inspired gas concentration) is determined by

A

FGF rate
breathing circuit volume
circuit absorption

6
Q

At equilibrium, CNS partial pressure will = _____, which will = ______

A

CNS partial pressure= blood partial pressure = alveolar partial pressure

Palveoli=Pblood=PCNS

7
Q

FA/FI ratio is the

A

degree to which the alveolar concentration of an anesthetic becomes closer to the inspired concentration of an anesthetic, expressed as a ratio

The rate at which the alveolar concentration of anesthetic equals the inspired concentration of anesthetic

8
Q

Three factors that affect FA/FI ratio

A

minute ventilation
blood:gas partition coefficient
cardiac output

9
Q

Cardiac output has a ______ relationship with speed of induction

A

inverse

10
Q

Sevo is _____% metabolized
Iso is _____% metabolized
Des is _____% metabolized

A

Sevo is 2 % metabolized
Iso is 0.2 % metabolized
Des is 0.02 % metabolized

11
Q

FA (alveolar gas concentration) is determined by

A

uptake
ventilation
the concentration effect and augmented inflow effect

12
Q

Fa (arterial gas concentration) is determined by

A

ventilation/perfusion mismatching

13
Q

The concentration effect is

A

administration of 2-3 times desired concentration of a gas until the desired depth of anesthesia is reached

14
Q

second gas law/ augmented inflow effect is

A

the simultaneous administration of a “slow” agent with a “fast” agent, theoretically can speed the onset of the slower agent
(theoretical concept, clinically insignificant)

15
Q

The ventilation effect is

A

the faster and more deeply a patient breathes or is ventilated the faster a patient loses consciousness at the start of the anesthetic.
Inhalation anesthetics move down a concentration gradient

16
Q

Normally, alveolar and arterial anesthetic partial pressures are assumed to ______

A

equalize

17
Q

Fa is consistently less than end-expiratory gas would indicate __________. This may be due to _____, _______, _______.

A

ventilation/perfusion mismatch

due to venous admixture
alveolar dead space
non-uniform alveolar gas distribution

18
Q

In a right to left cardiac shunt, there is a ______ anesthetic need.

A

Increased

19
Q

In a left to right cardiac shunt, there is a ______ anesthetic need.

A

decreased

20
Q

Oil/gas solubility is a indicator of

A

potency and lipid solubility

the higher the oil/gas solubility, the higher the potency and the higher the lipophilicity

21
Q

The Meyer-Overton correlation states that the

A

potency of an anesthetic can be predicted from its liposolubility

22
Q

The blood/gas partition coefficient is an indicator of

A

how fast the onset is. The lower the number the faster the onset.

23
Q

The pressure exerted by the molecular collisions of the gas against the container walls is known as

A

Vapor Pressure

24
Q

As long as liquid remains in a container, the vapor pressure is ________ of the volume of the liquid

A

independent

25
Q

Vapor pressure is proportional to

A

temperature

26
Q

For any mixture of gases in a closed container, each gas exerts a pressure proportional to its fractional mass; this is known as

A

Partial Pressure

27
Q

The sum of the partial pressures of each gas in a mixture of gases equals the total pressure of the entire mixture, this is known as

A

Daltons Law

28
Q

Term used to describe the tendency of a gas to equilibrate with a solution, hence determining its concentration within the solution

A

Solubility

29
Q

The relationship of concentration of a gas in solution to the partial pressure of the gas with which the solution is in equilibrium

A

Henry’s Law

30
Q

In the gas phase, fractional concentration (% by volume) is equal to the

A

partial pressure divided by ambient pressure

31
Q

The _________ is used for any gas in equilibrium with a liquid, a certain volume of that gas dissolves in a given volume of liquid

A

solubility coefficient

32
Q

The concentration of each gas in a mixture of gases in solution depends on two factors:

A

partial pressure in gas phase in equilibrium with the solution
Its solubility within that solution

33
Q

Anesthetic gases diffuse from the lungs into the blood until the partial pressures in the _____ and _____ are equal

A

alveoli and blood

34
Q

Concentrations of anesthetic in the blood depends on the _______ and the _______.

A

partial pressure of the gas at equilibrium

blood solubility

35
Q

The _________ of a gas in a solution represents the pressure that the gas in equilibrium with the liquid would have if a gas phase existed in contact with the liquid phase.

A

partial pressure

36
Q

The concentration of anesthetic in target tissue (brain) depends on the ______ and _______

A

partial pressure at equilibrium

target tissue solubility

37
Q

Monitoring the alveolar concentration of exhaled anesthetic provides an index of their ________

A

effect in the brain

38
Q

Inhaled anesthetics equilibrate based on their _________ in each tissue, not based on their concentrations

A

partial pressures

39
Q

Three factors that influence the uptake of volatile anesthetic:

A

Alveolar blood flow
Blood: gas solubility
partial pressure gradient between the alveoli and the venous blood