Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

AS - N926 Pharmacology > Inhalational Agents I > Flashcards

Inhalational Agents I Flashcards

1
Q

Amnesia

A

Loss of memory

Forget

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Analgesia

A

Loss of sensation and pain control

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Areflexia

A

Lack of movement

Skeletal muscle relaxation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

General Anesthesia MOA

A

Altered transmission in cerebral cortex

Additional effects on brain stem arousal centers, central thalamus, and spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Anesthesia Stages

A

I Amnesia & Anesthesia
II Delirium & Excitation
III Surgical Anesthesia
IV Anesthetic Overdose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Stage I

A

Amnesia & Anesthesia
Initiation of anesthesia to the loss of consciousness; patient able to follow simple commands, protective reflexes remain intact, eyelid reflex intact
Drift off to sleep
Induction - irregular pulse and normal BP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Stage II

A

Delirium & Excitation
Loss of consciousness and lid reflex, irregular breathing pattern, dilated pupils
Neurons that inhibit excitation are not functional and can lead to vomiting, laryngospasm cardiac arrest and emergence delirium
More exaggerated in younger individuals
Hyper-reactive
Broncho or laryngospasm
Excitement - irregular and fast pulse w/ elevated BP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Stage III

A

Surgical Anesthesia
Cessation of spontaneous respirations, absence of eyelash response and swallowing reflexes
NO airway protection
Operative - steady slow pulse and normal BP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Stage IV

A

Anesthetic Overdose
Cardiovascular collapse requiring provider intervention
DANGER - weak and thready pulse w/ low BP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Factors that impact Anesthetic choice:

A 
Proposed surgery
Patient comorbidities
Provider experience
Surgeon - capabilities & limitations
Anesthetic agents available
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Pharmacokinetics

A

Liquid vaporization
Main factors in anesthetizing patient:
- Technical & machine related
- Drug specific
- Patient factors (respiratory, circulatory, tissue)
Absorption r/t ventilation, blood uptake, CO, blood solubility, alveolar to blood partial pressure difference
Concentration or partial pressure in lungs assumed to be equal in brain
Gas dose expressed as MAC - age dependent peaks at 6mos & decreases w/ age
Faster lung concentration rises, faster anesthesia achieved

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

MAC

A

Minimum alveolar concentration % required to produce anesthesia (lack of movement) in 50% population

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Factors that increase MAC required

A 
Hyperthermia
Drug-induced increases in CNS activity
Hypernatremia
Chronic alcohol abuse
*Assuming only utilizing gas to achieve effects*
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Factors that decrease MAC required

A 
Hypothermia
Elderly
Alpha 2 agonists
Acute alcohol ingestion
Pregnancy
Hyponatremia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Machine-Related Factors

A

Rubber & plastic machine pieces & CO2 absorbent able to retain gas delaying initial uptake
Liter flow carrier gas - air, oxygen, nitrous oxide
Increasing liter flows during induction accelerates agent intake

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Gas-Related Factors

A

Blood:Gas solubility
Amount gas dissolves or becomes unavailable - binds to blood vs. amount able to diffuse into the tissues
Gas bound to blood unable to cross the blood-brain barrier
Factors that determine how fast an anesthetic gas is delivered to the tissues
Low blood solubility coefficient indicates availability to tissues (faster rate increase in lung and brain concentrations)

17
Q

Ventilation-Related Factors

A

All inhalational agents move down concentration gradient
Uptake slow as drug redistributes into tissue
Ventilation rate & depth influence uptake on distribution & removal on emergence
Ventilation-perfusion defects alter uptake
Anesthetics w/ low blood solubility coefficient more impacted

18
Q

Concentration

A

Over-pressurizing or concentration effect
Administer higher gas concentration than necessary to speed up initial uptake
Increased effect on high solubility gases

19
Q

Second Gas Effect

A

Co-administer slower agent w/ nitrous oxide to increase onset 2nd agent
Not entirely understood - large N2O uptake concentrates 2nd gas?
Also used during emergence to quickly remove slower gas

20
Q

Tissue-Related Factors

A

Oil:Gas solubility
Indicates potency
Highly lipid soluble drugs tend to be more potent
How efficiently that anesthetic gas can access the tissues to cause its effect

21
Q

Circulatory-Related Factors

A

Circulatory system influences anesthetic gases uptake & distribution
1° blood distributed to vessel rich organs or central compartment
↑ CO → slow uptake
High solubility gases are affected more (Isoflurane)

22
Q

Metabolism-Related Factors

A

Modern anesthetics are minimally metabolized
Breathe in & breathe out
Historically various agents were associated w/ toxic metabolites (Halothane hepatitis - hepatotoxicity)
Sevoflurane 5-8% liver metabolism releases free fluoride ions
*Only modern anesthetic agent w/ metabolism

23
Q

Temperature-Related Factors

A 
Hypothermia:
↑ potency & solubility
↓ tissue perfusion → slowed induction
Overcome w/ ↑ gas concentration
↑ tissue anesthetic capacity → slowed recovery

Hyperthermia:
↑ CO ↑ anesthetic requirement → slowed induction

GOAL: Normothermia

24
Q

Emergence Phase 1

A

Stop anesthetic drugs
Reverse NMBA
Transition from apnea to breathing
Increase alpha & beta waves on EEG

25
Q

Emergence Phase 2

A 
Increased HR/BP
Return autonomic responses
Responsive to pain
Salivation, tearing, grimacing
Defensive posturing
Swallowing & gagging
Extubation possible*
26
Q

Emergence Phase 3

A

Eye opening
Response to verbal commands
Awake EEG patterns
Extubation possible

27
Q

Malignant Hyperthermia Precautions

A

All inhalational anesthetic except N2O able to trigger malignant hyperthermia
Flush 10L/min for 20min
Replace all breathing circuits & CO2 absorbent
Remove vaporizers
Charcoal filters on inspiratory & expiratory limbs
Keep gas concentration at <5 ppm for 12hrs at 3 lpm

28
Q

Emergence-Related Factors

A

Longer an anesthetic gas used during case → slower emergence
Higher solubility gases = slower emergence
Isoflurane → Sevoflurane → Desflurane → Nitrous oxide
Routine practice to administer 100% oxygen

29
Q

Diffusion Hypoxia

A

Anesthetic leaves the blood via lungs w/ ventilation (except Sevo 5-8% metabolized)
Patients receiving nitrous oxide should receive 100% FiO2 on emergence to prevent atelectasis
High concentration insoluble anesthetics (N2O) delivered rapidly exits the lungs during emergence & replaced by Nitrogen resulting in less soluble gas dilution (oxygen & carbon dioxide)
100% FiO2 prevents this phenomenon

30
Q

Anesthesia

A

Stable administration of anesthetic drugs

31
Q

Emergence as compared to Induction

A

Tends to be smoother than induction
Especially true after longer cases

Not as accurate in pediatrics
Exaggerated stages
Flow more important than FiO2
10L 30% vs. 5L 100%

AS - N926 Pharmacology (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions