Nagelhout Local Anesthetics 2 - Exam 2 Flashcards
(95 cards)
T/F Pregnancy enhances the effects of LA.
true
-more sensitive to LA
T/F Epidurals, even when placed properly, can cause decreased uterine tone, slows labor, and affects uterine/ umbilical blood flow
FALSE
T/F If a pt with preeclampsia receives repeated epidural injections of lidocaine, they can develop greater accumulation of LA
true
Which LA drug has greater cardiotoxicity, predisposing it to causing ventricular arrhtyhmias?
Bupivacaine
T/F Ropivacaine and Levobupivacaine can cause even higher cardiotoxic effects than standard racemic bupivacaine
false
T/F LA are teratogenic
false
Fetal acidosis results in a greater accumulation of _ (amide/ester) LA in the fetus
amide
The elimination half life of amide LA is _ (shorter/longer) in newborns than in adults
longer
-fetuses have larger volume of distribution, ALSO more acidotic
T/F Compared to adults, fetuses and newborns are more vulnerable to the toxic effects of LA
false
T/F Neonatal neurobehavior solely depends on the choice of LA
false
Alkalinization of LA solutions _ (shortens/lengthens) the latency of neural blockade but increases the risk of _ when giving epidurals.
shortens the latency (speeds onset)
HoTN
Neuraxial opioid anesthesia produces analgesia without the loss of _ or _
sensation or proprioception
Combining neuraxial LA and opioids _ (increases/decreases) block density and allows for admin of a _ (higher/lower) total dose of LA
increases
lower
-reduces S/E risk too!
Spinal bioavailability of hydrophilic drugs (morphine and hydromorphone) are _ (more/less) than hydrophobic drugs (fentanyl, sufentanil)
less
3 most common S/E of neuraxial opioid admin are:
-pruritis
-N
-V
-fetal bradycardia and maternal resp depression are the most serious tho
What is the benefit of mixing 2 different LA?
-helps speed onset and prolong duration when done properly
Mixing LA compensates for the _ duration of short -acting agents (Lido, chloroprocaine) and the _ latency of long-acting agents (Tetracaine, Bupivacaine)
short
long
Use of _ techniques for regional anesthesia make it possible to give a rapid acting LA then start a short or long acting infusion.
catheter
T/F Due to LA toxicities being different between drugs, when mixing them, you are able to give both max doses.
FALSE!
-cut toxic doses to whatever % of the total mix solution
ex) you want a 50/50 bupivacaine and lidocaine solution: give 3.5 lidocaine and 1.5 bupivacaine
T/F Spread and depth of LA is less in pregnant pts than nonpregnant pts
false
-pregnant pts have LA spread more and works more significantly
-why?: mechanical and hormonal change-most likely a hormonal factor
T/F LA doses should be cut in pregnant pts, but especially in their 1st trimester
true
-hormone changes(progesterone) are the most significant factor increasing the spread/depth of LA, NOT gravid uterus
If you give a max dose of a spinal LA at the start of a procedure for a patient, and the surgeon asks if they can give some more 1.5 hr into the case, can they give more LA?
yes
-can safely readminister LA 90 mins after the max dose is given
Tumescent anesthesia, known for its use during liposuction, is more common with _ _ procedures in NORA settings
minimally-invasive
Tumescent anesthesia involves injecting lidocaine into fat during liposuction at doses of _ - _ mg/kg.
35-55mg/kg
-conc can peak 12-16 hr after infusion
