FLUID RESUSC Flashcards
(20 cards)
Your trauma patient has received 6 units of pRBCs and 4 units of FFP for ongoing resuscitation prior to arriving at your Role 3 facility. The patient continues to be hypotensive despite bedside TTE showing adequate volume in his IVC. Assuming none of the medications below have been given yet, which medication will correct his underlying issue.
A. Tranexamic acid 1g
B. Hypdrocortisone 100mg
C. Vasopressin 5 units
D. Calcium chloride 1g
Given the context of massive transfusion (6 units pRBCs, 4 units FFP) and persistent hypotension despite adequate IVC volume, hypocalcemia due to citrate toxicity is a highly likely underlying metabolic derangement. Correcting this with calcium chloride directly addresses the impaired myocardial function and vasodilation caused by low calcium, thus correcting the underlying issue contributing to hypotension.
While vasopressin addresses vasodilation, hypocalcemia directly causes myocardial depression and vasodilation as a complication of the resuscitation itself. Therefore, addressing the hypocalcemia is a more fundamental correction of an underlying physiological derangement in this specific scenario.
Which metabolite is NOT correctly linked to its parent drug?
A. Normeperidine – meperidine
B. Morphine-6-glucuronide – morphine
C. Morphine – codeine
D. Hydroxyfentanyl – fentanyl
D. Hydroxyfentanyl – fentanyl: This is NOT correct. The primary and major inactive metabolite of fentanyl is norfentanyl, formed by N-dealkylation. While fentanyl can undergo other minor metabolic pathways, hydroxyfentanyl is not its major or commonly cited metabolite.
Which of the following is the shortest-acting opioid (shortest terminal context sensitive half-time)?
A. Fentanyl
B. Remifentanil
C. Alfentanil
D. Sufentanil
Let’s look at approximate CSHTs for these opioids (which vary depending on infusion duration and source, but the relative order is consistent):
Remifentanil: ~3-5 minutes (largely independent of infusion duration)
Alfentanil: ~50-90 minutes (can increase with longer infusions, but less than fentanyl)
Fentanyl: ~260 minutes after a 4-hour infusion, can increase significantly with longer infusions.
Sufentanil: ~1 hour after a 6-hour infusion, generally shorter than fentanyl’s CSHT for prolonged infusions, but longer than alfentanil.
What is the correct sequence of tissue layers through which the needle ideally passes when administering spinal anesthesia?
1/1
a) superficial fascia, supraspinous ligament, interspinous ligament, ligamentum flavum, epidural space, subarachnoid space
b) superficial fascia, interspinous ligament, supraspinous ligament, ligamentum flavum, epidural space, subarachnoid space
c) superficial fascia, interspinous ligament, supraspinous ligament, ligamentum flavum, subarachnoid space, epidural space
d) superficial fascia, ligamentum flavum, supraspinous ligament, interspinous lig., epidural space, subarachnoid space
a) superficial fascia, supraspinous ligament, interspinous ligament, ligamentum flavum, epidural space, subarachnoid space
The most important factor affecting the levels achieved with an epidural anesthetic is:
a) Addition of epinephrine to local anesthetics
b) Number mg of local injected
c) Volume of solution injected
d) The local anesthetic utilized
c) Volume of solution injected: When a local anesthetic solution is injected into the epidural space, it spreads cephalad and caudad (up and down the spinal canal) primarily due to the physical volume of the injectate. A larger volume will occupy more of the epidural space, contacting more nerve roots, and thus resulting in a higher dermatomal level of sensory and motor blockade.
Which of the following opioids may cause an increased HR and mydriasis?
a) morphine
b) fentanyl
c) remifentanyl
d) meperidine
D
a) Morphine: Typically causes bradycardia and miosis.
b) Fentanyl: Typically causes bradycardia and miosis.
c) Remifentanil: Typically causes bradycardia and miosis.
d) Meperidine (Demerol): This is the opioid that is known to cause tachycardia (increased HR) and mydriasis (pupil dilation). This is due to its structural similarity to atropine (an anticholinergic) and its weak anticholinergic properties, as well as its interaction with other receptors (e.g., kappa and delta opioid receptors, and potentially some serotonin reuptake inhibition).
Choose the item below that places the opioids in the correct order from least potent to most potent.
fentanyl,
sufentanyl,
meperidine,
morphine,
remifentanyl
a) meperidine, morphine, fentanyl, remifentanyl, sufentanyl
Which of the following opioids has an active metabolite?
A. Alfentanil
B. Meperidine
C. Remifentanil
D. Fentanyl
Meperidine is the opioid among the choices that has a clinically significant active metabolite.
A. Alfentanil: Alfentanil is primarily metabolized in the liver by the CYP3A4 enzyme system to inactive metabolites. It does not have clinically significant active metabolites.
B. Meperidine: Meperidine (Demerol) is metabolized in the liver primarily by N-demethylation to normeperidine. Normeperidine is an active metabolite with both analgesic properties (though less potent than meperidine) and significant CNS excitatory effects, including tremors, myoclonus, and seizures, especially with accumulation in renal impairment or prolonged use.
C. Remifentanil: Remifentanil is unique among opioids due to its metabolism by non-specific plasma and tissue esterases to inactive carboxylic acid metabolites. This rapid metabolism to inactive forms is why its offset of action is so rapid and independent of infusion duration.
D. Fentanyl: Fentanyl is primarily metabolized in the liver by the CYP3A4 enzyme to norfentanyl. Norfentanyl is generally considered inactive or to have very minimal opioid activity.
Early signs of local anesthetic toxicity after intravenous administration include all of the following except:
0/1
A. Tinnitus
B. Tachycardia
C. Agitation
D. Metallic Taste
B. Tachycardia
Addition of epinephrine to lidocaine
A. Speeds absorption and increases peak blood levels.
B. Prolongs duration of action of lidocaine.
C. Has no effect on systemic toxicity.
D. Causes local vasodilation.
B. Prolongs duration of action of lidocaine.
Tachyphylaxis
Tachyphylaxis is a phenomenon where there is a rapid decrease in response to a drug after repeated administration over a short period. In the context of local anesthetics, it means that subsequent doses of the local anesthetic produce a weaker or shorter-lasting block than the initial dose.
The drug you should avoid in a patient with a history of procaine allergy is:
a) Bupivacaine
b) Etidocaine
c) Lidocaine
d) Tetracaine
Tetracaine
Systemic toxicity of local anesthetics may initially manifest as the following clinical symptoms:
a) systemic hypotension and/or dysrhythmias
b) restlessness, tinnitus, seizures
c) hyperthermia and delirium
d) parasthesias and/or dysasthesias
restlessness, tinnitus, seizures
50 cc of lidocaine 1% with epinephrine 1:200,000 contains:
0/1
a) 50 mg lidocaine and 250 mcg epinephrine
b) 50 mg lidocaine and 100 mcg epinephrine
c) 500 mg lidocaine and 250 mcg epinephrine
d) 500 mg lidocaine and 25 mcg epinephrine
c) 500 mg lidocaine and 250 mcg epinephrine
Why is bupivacaine more cardiotoxic than lidocaine?
bupivacaine more slowly dissociates from the cardiac sodium channels
The major action of local anesthetics is to
Decrease sodium conductance
Amino esters are metabolized by which of the following?
1/1
A. Hepatic microsomal enzymes
B. Plasma esterases
C. Pseudocholinesterase
D. Acetylcholinesterase
B. Plasma esterases
A healthy G1 at term gestation is admitted to the labor and delivery unit for induction of labor. As she progresses, she requests an epidural for labor analgesia. The patient is properly positioned and the anesthesiologist performs a midline approach to placing a lumbar epidural. In order, name the layers that the needle will traverse before it enters the epidural space.
Skin -> Subcutaneous tissue -> Supraspinous ligament -> Interspinous ligament -> Ligamentum flavum
In the diagram above, at which of the following sites do local anesthetics mainly exert their effects?
C
What sie effects do we see with meperidine that we dont get with opioids like fentanyl or morphine?
Meperidine (Demerol) possesses weak anticholinergic properties due to its structural similarity to atropine.
