1 Flashcards
how does acetaminophen differ from salicylates?
no gastric irritation, does not affect plt aggregation, no anti inflam properties
2 prime indications for acetaminophen
-analgesia
-antipyreixa
very little antiinflammatory properties
what are the 2 components of the circle system test on an anesthesia machine? between what 2 machine components does the circle system test?
circle system test evaluates circle breathing system from common gas outlet to y piece
consists of 2 parts: leak test and flow test
most common critical incident in anesthesia
due to breathing circuit disconnections- most commonly happens at y piece!!
an optimal face mask seal will allow for maintence of an airway with no leak at what pressures
at an airway pressure between 20-25
what are the two main factors that determine the resistance to gas flow in an anesthesia circuit?
length of the tube and its diameter
shorter the length and larger diameter- less resistance it offers
what ETT would be best for surgery involving significant flexion of the neck?
armored ETT containing spiral wire in the tube to prevent kinking or bending when neck is flexed
when would high flow nasal warmed humidified oxygen administration be beneficial
high flow nasal warmed humified oxygen administration at flows 30-70 would be beneficial for procedures where rapid oxgen desat is likely such as hypopharyngeal or laryngotracheal procedures
why should be cuff pressure be monitored in pt undergoing long term ventilation via ett
too high-> ischemia of trachea wall. low cuff pressure in the ett increases risk material can pass beside the cuff and into lungs- increased risk of pneumonia in pt on long term ventilation
concerns of 1st generation LMA
does not protect against gastric secretions. ventilation requiring pressures > 20 may result in inflation of stomach.
-can become malpositioned-> inability to ventilate
-c/i in pharyngeal pathology such as tumor or abscess
-pathology at or below level of LMA may make it an ineffective means of ventilation
the plasma half life is inversely proportional to its
rate of clearance
hepatic enzyme induction will result in a reduction in the ___ of a drug
half life
if liver enzymes are exposed to a particular compounds or drugs over a period of time, they will increase their activity, resulting in increased ability to metabolized drugs (hepatic enzyme induction)-> reduces half life of a drug
what plasma proteins bind preferentially to acidic drugs?
albumin
alpha 1 acid glycoprotein and beta globulin bind preferentially to basic drugs
when you bolus a drug IV, what tissue will have an increase in the tissue concentration of the drug first?
liver
vessel rich group: brain, heart, liver, kidneys, lungs, and endocrine
then it goes to muscle, adipose, and bone
plasma half life of a drug is directly proportional to its
volume of distribution
what is ion trapping
when the lipid soluble portion of a basic drug like lidocaine crosses the placenta and enters the acidic enviornment of the fetus, the drugs becomes more ionized and unable to cross back through the placenta.
as a result, a higher concentration of the drug exists in the fetus than in the mother.
at a ph of 7.3 if you administer a drug with a pka of 4.5 how much of the drug would you expect to be ionized
> 50%
at a ph of 7.3 if you administer an acidic drug with a pka of 8.1 how much of the drug would you expect the be ionized
<50%
bases are more ionized below the ph and acids are more ionized above
at a ph of 7.3 if you administer an acidic drug with a pka of 7.3 how much would you expect to be ionized
50%
bases are more ionized below the ph and acids are more ionized above
less ionized=
more non ionized, more lipid soluble, less charged, more likely to cross the cell membrane
Drug A is an acid with a pKa of 9 and Drug B is a base with a pKa of 7.4. When injected into the bloodstream, which will cross the cell membrane most easily?
Drug A is an acid that has a pKa that is below the pH on the mnemonic diagram. This means that it is less ionized (and more non-ionized). The base (Drug B) has a pKa that is the same as the pH of the blood which means it is exactly 50% ionized and 50% non-ionized. Since the acid is more non-ionized, it will be able to cross a cell membrane more easily.
approximately what % of CO goes to adipose tissue group
6
formula for clearance
clearance= blood flow x extraction ratio
what is the LMA size for 35 kg
3
what nerve does the transtracheal block anesthetize?
RLN
penetrate cricothyroid membrane into the trachea
3-5 mL of 2% lidocaine
inject on end expiration-> cough-> spread anesthetic throughout airway
what nerve provides sensation to the anterior 2/3 of the tongue
lingual nerve (branch of trigeminal)
what kind of block is injection of 3 mL of 2% lidocaine bilat 1 cm below each greater cornu of the hyoid
SLN block- anesthetizes airway below the epiglottis and portion of epiglottis itself
how big should thyromental distance be for an adult
6-9 cm (3 fingers)
measure with mouth closed and head extended
what scoring system is used to objectively describe difficulty of laryngoscopy?
cormack and lehane
what complication of an esophogeal intubation is associated with highest mortality rate
mediatinitis - 50% mortality
what 2 rbanches of glossopharyngeal n will be anesthetizes by injecting 2 mL of local at the base of the palatoglossl arch
pharyngeal and lingual
what is the first step for tx laryngospasm
remove offending stimulus
following a difficult intubation, you suspect the patient may have obstructin of the submandubular duct due to trauma establishing the airway. this condition would present as
swelling of the tongue
what method can help prevent lens fogging when using a flexible fiberoptic laryngoscope
soak the scope in warm water
fogging is more common if scope is cold
in pacu, a peds pt exhibits a barking cough and a stridorous sound during respirations. what would be the most appropriate innital treatment?
racemic epi and humidified oxygen
what are the advantages of a lighted stylet over traditional laryngoscopy
-less affected by anterior airway
-associated with lower incidence of sore throat
-less stimulating than traditional laryngoscopy
what nerve provides sensation to the larynx below the vocal cords?
external laryngeal nerve
a cricothyrotomy is performed by inserting a cannula into
the membrane between thyroid and cricoid cartilage
what is the largest size ett the LMA fasttrach (intubating LMA) will accomidate?
8.5
you are administering a LA intranasally to block the anterior ethmodial and sphenopalatine nerves. you know these nerves are braches of the
trigeminal nerve
nose is innervated by opthalmic division of trigeminal nerve (V1) anterior and maxillary division of the trigeminal nerve (v2) posteriorly
under what structure does the R recurrent laryngeal nerve pass?
R RLN branches off the vagus nerve and passes under the innominate artery
L RLN branches off the vagus nerve and passes under the aorta
what muscles lenghen and increase the tension of the vocal cords?
cricothyroids