Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
49 Cards in this Set
- Front
- Back
How did Wells contribute to founder of anesthesia
|
-saw person on nitrous hit table and feel no pain
-gave himself nitrous while another dentist took out wisdom teeth -demonstrated at Harvard but student cried out |
|
How did Morton contribute to foundation of anesthesia
|
-followed up Wells, went to Harvard med and administered ether while surgery was performed
|
|
What are some factors that can modify someone's pain threshold
|
-emotional state
-fatigue -age -fear -past experience -drugs |
|
What are the four conceptual ways to control pain
|
block pathway - local anesthesia
raise threshold - analgesic, N2O modify reaction to pain - CNS depression (tranquilizers) psychosomatic methods - iatrosedation, hypnosis (used w/other methods) |
|
What does local anesthesia block and not block
|
-eliminates pain but not pressure, noise, or visual sensations
|
|
How does nitrous help with pain control
|
-decreases patient's perception of local anesthesia injection and other stimuli
|
|
What is conscious sedation
|
-sedating a patient who is still capable of a rational response to a command and has protective reflexes intact including ability to clear and maintain airway
|
|
What are the 5 objectives/goals of nitrous sedation
|
-gain confidence of the patient
-break fear of dental treatment -demonstrate that dental tx is not unpleasant -provide calm atmosphere that benefits patient, dentist and staff -comfort 'normal' patient during painful procedures |
|
T/F - nitrous oxide has an odor
|
-false = tasteless, odorless, colorless, inorganic
|
|
How is nitrous oxide stored
|
-97% pure, blue cylinder, (650-800 psi)
-30% in liquid form in cylinder |
|
What are common impurities of nitrous oxide
|
-nitrogen, ammonia
|
|
T/F - nitrous oxide is flammable
|
-false, it is non-flammable, non-explosive, but can combust
|
|
How is oxygen stored?
-how is the tank read |
-green tank
-full tank = 2000, half full = 1000, empty = 0 |
|
How is nitrous oxide stored?
-how is the tank read |
-blue tank
-full = 750, half full = 750, 20% full = 750, empty = 0 -this is because of the liquid in the tank |
|
N2O Pharmacology:
-strength as a GA -MAC -analgeic strength -highest safe concentration |
-weak GA
MAC = 105% -powerful analgesic -65-70% |
|
What is MAC
|
minimum alveolar concentration - concentration required to keep 50% of humans from respondign to a surgical incision
|
|
What % of nitrous oxide is equal to 10-15 mg of morphine
|
-20% N2O
|
|
What is the optimal analgesic concentration for nitrous
|
35% N2O and 65% oxygen
|
|
What two things are affected for the patient
|
-ability to interpret noxious stimuli as painful
-changes patients attitude toward pain |
|
T/F - N2O reacts in the body
|
-false, no chemical reactions take place
|
|
T/F - nitrous oxide is poorly soluble in blood and tissue
|
-true
|
|
Why is there such a rapid induction of analgesia
|
-because nitrous oxide is so poorly soluble
|
|
What is the tissue saturation with N2O after 5 min
|
90%
|
|
What are the CV effects from nitrous
|
-slight depression of myocardial contractility
-slight decrease in peripheral resistance with resultant cutaneous vasodilation -blood pressure stable, can decrease as sedation continues |
|
What are the respiratory effects from nitrous?
|
-increase in respiratory minute volume
-minimal effect on rate -non-irritating to respiratory epithelium |
|
How is nitrous eliminated from the body
|
-primarily through the lungs
-mostly within 3-5 min after termination of delivery |
|
What is diffusion hypoxia and what may cause it
|
-due to rapid diffusion of nitrous oxide and dilution of oxygen coming in
-so give 100% O2 for 3-5 min after nitrous is turned off |
|
T/F - nitrous should be used for patients who are overly apprehesive
|
-false, should give them IV sedation
|
|
T/F - it is appropriate to use nitrous on the very young, mentally retarded or psychiatric patient who is unable to communicate verbally
|
-false
|
|
What are 4 indications for nitrous oxide sedation
|
-mildly apprehensive pt not involving a long procedure
-child who is not used to dental treatment -medically compromised pt requiring a light sedation -pts with a hyperactive gag reflex |
|
List 6 absolute contraindications to nitrous oxide
|
-active upper airway infection
-severe COPD -sickle cell anemia -any condition that does not allow use of LA -significant cardiac decompensation -uncooperative patient |
|
List 7 "relative" contraindication to nitrous oxide
|
-severe asthma
-alcohol/drug dependence -age extremes -pregnancy -patients who are afraid of losing control -patient who wants to be asleep -claustrophobic patient |
|
List 3 "situational" contraindications to nitrous oxide
|
-patient with a full stomach (should be NPO for 4 hours)
-acute anxiety -no escort |
|
What should you do before treating a patient with nitrous
|
-determine physical condition
-define their emotional state, anxiety level -determine if sedation is needed |
|
What should patients be told about nitrous before appointment
|
-that the pt will not be asleep, just relaxed
-NPO for 4 hours -pt will need an escort |
|
What is the technique for administering nitrous
|
-get informed consent
-record baseline vitals -place pt in semi-reclined position -fit nasal hood -start oxygen at 8 L/min -turn on nitrous and increase by 1 L/min (decrease O2 by 1 L/min) so overall flow is 8 L/min -encourage steady breathing, not deep breathing |
|
When should you first evaluate pt sedation level
|
-at 30% nitrous/70% oxygen
|
|
At what concentrations do unpleasant sensation occur
|
50% nitrous
|
|
When is LA given
|
-when baseline level of sedation is achieved
|
|
What are the signs/symptoms in response to N2O at the following levels:
10-20% 20-30% 30-40% |
10-20 = body warmth, tingling of hands and feet
20-30 = circumoral numbness, numbness of thighs 30-40 = numbness of tongue, hands, feet, droning sounds, hearing distinct but distant, mild sleepiness, analgesia, euphoria, feeling of heaviness or lightness, dissociation |
|
What % of N2O is max analgesia
|
35%
|
|
What are the signs/symptoms of N2O at the following concentrations:
30-50 40-60 50 and up |
30-50 = sweating, nausea, amnesia, sleepiness
40-60 = dreaming, laughing, giddiness, increased N/V, increased sleepiness 50 and up = unconsciousness and light GA |
|
What are the three C's to monitor is regard to sedation
|
-level of conciousness
-level of comfort -level of cooperation |
|
What are some indications to decrease the concentration of nitrous
|
-pt feels uncomfortable
-nausea -pt is poorly responsive to verbal commands -pt makes uncoordinated movements -pt is uncooperative |
|
What vitals should be monitored while on nitrous
|
-respiratory rate
-heart rate -blood pressure -oxygen saturation |
|
What are common complications of nitrous
|
N/V - <1% at conc of <50%
diaphoresis - secondary to peripheral vasodilation and stimulation of sweath glands -hypoxia |
|
What are predisposing factors to nausea/vomiting
|
-full stomach
-kid -hypoxia ->50% nitrous |
|
What are the signs of hypoxia
|
-cyanosis, tachycardia, tachypnea, bradycardia, restlessness, drowsiness, unconciousness, N/V, distress
|
|
What are the effects of chronic exposure to nitrous
|
-spontaneous abortion
-congenital abnormalities -hepatic/renal disease -neurlogic disease -hematologic disease |