10-Nitrous Oxide Pt. 2

Question 1

T/F there are no contraindications with N2O and the cardiovascular system

Answer 1

true
sometimes it’s beneficial for them (e.g. suspected MI: morphine or 50% N2O)

Question 2

with the respiratory system which disease would we be most concerned about?

Answer 2

severe COPD

Question 3

when will we want to avoid using nitrous with the respiratory system?

Answer 3

Gas retention with increased pressure– avoid use
Sinusitis
Middle ear disturbance/surgery
Cystic fibrosis & severe COPD– bullae as consequence of disease
Pneumothorax
Certain recent ophthalmic surgeries

Question 4

T/F you can’t do nitrous if the pt has anemia

Answer 4

false
no contraindications with N2O and hematopoietic system

Question 5

T/F with the endocrine, hepatic, GI, genitourinary, and neuromuscular systems you are ok to do N2O

Answer 5

true

Question 6

what chemotherapy drug is a contraindication for N2O?

Answer 6

Bleomycin sulfate therapy
increases incidence of pulmonary fibrosis and other pulmonary diseases

Question 7

what surgery is contraindicated for N2O?

Answer 7

Vitreoretinal surgery – gas bubble placed to assist healing
Middle ear – tympanic membrane rupture, graft displaced

Question 8

what drugs are contraindicated for N2O?

Answer 8

Antidepressants or psychotropic drugs
Recovering alcohol and drug addicts
when taking meds to induce sleep (Combined oral/inhalation sedation – increased depth)

Question 9

what gene mutation is contraindicated with N2O? what happens?

Answer 9

MTHFR (involved with vit. B12 prod)
can result in irreversible, catastrophic neurological damage or even death

Question 10

how long should a pregnant mother be exposed to N2O if needed for tx?

Answer 10

30 min

Question 11

what trimester can a pregnant pt use N2O?

Answer 11

2nd/3rd

Question 12

what percentage of O2 should be used if using N2O on a pregnant woman?

Answer 12

50%

Question 13

what happens with chronic N2O and pregnancy?

Answer 13

can cause cellular abnormality in animals (inactivation of methionine synthetase and vit B12)

Question 14

N2O affects Vit ______ metabolism

Answer 14

B12

Question 15

who are the primary victims of overexposure to N2O?

Answer 15

dentists or other helathcare providers delivering w/o scavenger systems

Question 16

what can a pt experience with N2O?

Answer 16

sexual phenomena
can accuse you of sexual assault while under drug effect
make sure another person is present

Question 17

what can unscavenged N2O do to you?

Answer 17

irreversible toxic changes associated with reproductive, neurological, hematological, immunological, renal and liver disease

Question 18

what reproductive effects does occupational exposure of N2O do to you?

Answer 18

Exposure to high levels of unscavenged N2O can decrease fertility
Exposure to high levels of unscavenged N2O can increase levels of spontaneous abortion and low birth weight
There is no significant increase in congenital abnormalities

Question 19

what neurological effects does occupational exposure to N2O do?

Answer 19

Neurological symptoms are loss of ability to concentrate, numbness of the extremities, paresthesia, ataxia, impotence, and loss of bladder and bowel sphincter control

Question 20

what are the health hazards with recreational abuse of N2O?

Answer 20

Chronic abuse
Hemotologic
Leukopenia
Megaloblastic changes
Pernicious anemia
Neurologic
Numbness – arm, legs, trunk
Equilibrium, gait disturbance
Impotence
Sphincter control
Inability to work, difficulty thinking

Question 21

what are the constituents of earth atmosphere?

Answer 21

78% - nitrogen
21% - oxygen
1% - trace amounts of various gases

Question 22

there is a major difference in partial pressure gradients b/t N2O and _____

Answer 22

N2 (nitrogen)
in high amounts in natural air and will displace N2O

Question 23

what solubility do you want?

Answer 23

Low solubility -
Blood-brain barrier crossed quickly
Equilibrium quickly achieved
Rapid onset

Question 24

T/F N2O is relatively soluble

Answer 24

false
insoluble

Question 25

T/F N2O is not metabolized by the liver

Answer 25

true

Question 26

N2O is the _________ inhalation agent?

Answer 26

least potent

Question 27

what is MAC?

Answer 27

minimum alveolar concentration

Amount of drug to prevent movement in 50% of patients subjected to surgical incision
MAC for N2O is 104-105%
Therefore, unable to produce surgical anesthesia by using nitrous alone, even if the patient was breathing 100% nitrous