Brain Dumps Flashcards
Which gas has the highest MAC?
N2O
Which gas does not have an etheral odor?
Halothane
TV x RR =
minute ventilation
What is the portion of breath which goes to the mouth, pharynx, and tracheobronchial tree but does not enter alveoli called?
Anatomic dead space
- The flow of anesthesia is:
PA –> Pa –> PBr
What is commonly used as the first gas in second gas effect?
N2O
What mode of ventilation do you lose the protective mechanism?
Mechanical
A Blood:gas partition coefficient of 0.5 =
the concentration of inhaled anesthetic in blood is ½ that of alveolar gases when partial pressure is equal in both phases
oil:gas of 150 =
?
- What stage of anesthesia do you want?
3
- What stage does divergent gaze occur
2
- What gas would you avoid in a pt with history of seizures?
Enflurane
- What clinical scenario would you give succ (renal, head injury, burns)?
Renal
- CBF of volatiles
Halo > Enflu > Iso = Des
- SVR decrease:
Iso > Des > Sevo
- HR increase:
Des > Iso > SEvo
- Do limit for exogenous Epi:
6 mcg/kg
- Which would you avoid in head injury?
Ketamine
- What causes MH?
Increase and continuous leaking of Ca from Ryanodine receptors of sarcoplasmic reticulum
- What would be your pick for NMBD for patient with chronic renal disease? Answers between Roc and Nimbex must know dose
?
- Most MH deaths are d/t ____ and _____.
DIC and delayed Dantrolene treatment
- Increased massestor tone is sign of?
MH after Sux
- Datronlene dose?
2.5 mg/kg every 5-10 minutes
- MOA – Etomidate
?
- MOA – Valium or propofol
?
- The LA least likely to cause fetal ion trapping
?
- Definitions of efficacy and potency
>
- Non ionized vs ionized
?
- More binding to plasma poteins less Vd (what affects)..
ND NMBD bind to protein and are poor lipid soluble high plasma concentration and low Vd
- What occurs during phase II?
Conjugation
- Ester drugs are metabolized by ?
Hydrolysis
- # of ½ lives vs. concentration of drug
?
- Effective TI for anesthesia :
LD1/ED99
- LD1/ED99 requires ______
vigilance
- Match receptor types (full agonist/antagonist/etc)
?
- 1st order vs 0 order elimination
?
- 65% is total body water, 35% is non-water mass
?
- Osmolarity formula?
?
Which anesthetic would you not use in a GI case?
Roc
Which agent has the greatest Vapor pressure?
?
N20 does NOT decrease Bp
>
How is sevo broken down?
Phase 1 or phase 2????
Which is NOT correct regarding Zero Order?
Constant fraction
Giving a beta agonist causing tachy?
Upregulation/downregulation
Halothane—
dose dependent ¯ CO
. The ability of the pulmonary vasculature to constrict in response to regional hypoxemia/ Nitrous inhibits HPV
?
- Ionization pick 3:
a. Determines degree of diffusion
b. Nonionized drugs are lipid soluble -> can absorb
c. Ionized drugs are lipid soluble -> cannot absorb
?
- 94% half time: 4 Half Times
?
- A medication has low lipid solubility = low volume distribution.
>
- B:G similarities: desflurane = sevoflurane
>
- Lipid and maybe oil solubility: book says parallel: think both items were 100:150 option
>
- GABA ligand – Etomidate
- GABA A agonist – Propofol
- Exerts effects on opioid receptors, monoaminergic, muscarinic, NA & CA, NMDA? Ketamine
- Zero order elimination:
a. Decreases linearly with time.
b. Rate of elimination is constant regardless of plasma concentration.
- Three sodium ions ejected and 2 potassium ions entered in the NA-K pump
- NA-K pump: Pick 2 maybe
a. Na/K transporter
b. Responsible for transmembrane electrical potential
- Cerebral Metabolic O2 Requirements:
Isoflurane = Desflurane= Sevoflurane > Halothane
- HPV pick 2:
a. The ability of the pulmonary vasculature to constrict in response to regional hypoxemia
b. Nitrous inhibits HPV.
- What antiepileptic drug should be used with caution in patients with diabetes?
a. Carbamazepine
b. Gabapentin
c. Valproic acid
d. Ethosuximide
VALPROIC ACID
- A young, healthy patient you’re assessing preoperatively begins to have a nonconvulsive generalized seizure. You, as the astute SRNA you are, know that you would NOT administer which medication? Test Question by Bo S. Davis
a. Phenobarbital
b. Ethosuximide
c. Lamotrigine
d. Valproate
PHENOBARBITAL
- A CRNA performs a train of four to detect the amount of twitches present. Upon stimulation, there are four twitches. As a knowledgeable CRNA, they administer a reversal agent due to what percentage of receptors being blocked?
a. 85% or less
b. 75% or less
c. 95% or less
d. 90% or less
75% OR LESS
Which statements are true regarding Felbamate? (Select 3)
a. Concomitant administration of carbamazepine or phenytoin may decrease plasma concentrations of felbamate
b. Felbamate can slow the metabolism of phenytoin, phenobarbital, and valproic acid
c. In receiving phenytoin, carbamazepine, or valproic acid the dose of the drugs should be increased by 20% to 30% to prevent toxic effects
d. in receiving phenytoin, carbamazepine, or valproic acid the dose of the drugs should be decreased by 20% to 30% to prevent toxic effects
A, B, D
a. Concomitant administration of carbamazepine or phenytoin may decrease plasma concentrations of felbamate
b. Felbamate can slow the metabolism of phenytoin, phenobarbital, and valproic acid
d. in receiving phenytoin, carbamazepine, or valproic acid the dose of the drugs should be decreased by 20% to 30% to prevent toxic effects
- An astute CRNA performs a train of four after giving Rocuronium. 2 out of 4 twitches were detected. With this knowledge, what dose of Sugammadex would the CRNA give
a. 5 mg/kg
b. 3 mg/kg
c. 2 mg/kg
d. 8 mg/kg
2 MG/KG
- Your patient has a large amount of secretions so you administer an anticholinergic. As an SRNA, you should monitor for all of the following common side effects EXCEPT for:
a. Tachycardia
b. Urinary retention
c. Mydriasis
d. Miosis
MIOSIS
- The SRNA is aware that a higher dose of non-depolarizing NMBD may need to be administered to which of the following patients? (select 3):
A) Patient with a twenty-year history of generalized seizures controlled with anticonvulsants
B) Patient who takes phenytoin 5mg/kg/day
C) Patient scheduled for a CABG with a pre-op K+ of 4.0
D) Patient scheduled for a parathyroidectomy with a pre-op Ca++ of 12.3
E)Patient who takes gabapentin 30mg/kg/day for partial seizures
A, B, D
A) Patient with a twenty-year history of generalized seizures controlled with anticonvulsants
B) Patient who takes phenytoin 5mg/kg/day
D) Patient scheduled for a parathyroidectomy with a pre-op Ca++ of 12.3
Rationale: Chronic use of anticonvulsants, hyperparathyroidism and hypercalcemia decrease potency of NMBDs (Slide 20, NMBD ppt). Patients receiving phenytoin have higher dose requirements for nondepolarizing NMBDs. Phenytoin induces hepatic enzymes and it is likely that metabolism and elimination of NMBDs is increased. Phenytoin may also produce mild blocking effects at the neuromuscular junction leading to upregulation of aCh receptors
- When reviewing a patient’s chart who had an anaphylactic reaction during anesthesia administration, which element is of most concern as to what caused the reaction?
a. The use of latex gloves
b. Penicillin administration
c. Rocuronium administration
d. Neostigmine administration
e. Thiopental administration
ROCURONIUM ADMIN
ii. Rationale: NMBD accounts for 58.2% of allergic reactions with latex (16.7%) and antibiotics (15.1%) following behind. Although standard doses of Rocuronium do not release histamine, it still accounts for 43.1% of anaphylaxis in front of succinylcholine at 22.6%. Thiopental accounts for 1/30,000 allergic reactions (pg 176).
- You are assessing your patient pre-op and learn that they have been taking phenytoin. Which of the following actions would you be most concerned with?
a. induction
b. intubation
c. emergence
d. administering IV sedation
INTUBATION
Rationale: Phenytoin causes gingival hyperplasia in 20% of patients.
- Epinephrine is the prototype sympathomimetic. Its natural functions upon release into the circulation include regulation of all of the following EXCEPT?
a. Myocardial contractility
b. Bronchial smooth muscle tone
c. Glycogenolysis
d. Stimulates insulin secretion
STIMULATES INSULIN SECRETION
Rationale: Epinephrine can inhibit peripheral glucose uptake, which is also due in part to inhibition of insulin secretion
- During the preoperative assessment, the patient tells the SRNA she takes Baclofen regularly at home. The SRNA knows the mechanism of action of Baclofen is (Choose 2):
a. Acts as an Agonist at GABAb receptors in the ventral horn of the spinal cord
b. Acts as an Agonist at GABAb receptors in the dorsal horn of the spinal cord
c. Centrally acting analeptic that also acts peripherally on chemoreceptors augmenting breath efforts
d. Provides analgesic effects through presynaptic and postsynaptic processes
e. Acts as an Antagonist at GABAb receptors in the dorsal horn of the spinal cord
B & D
b. Acts as an Agonist at GABAb receptors in the dorsal horn of the spinal cord
d. Provides analgesic effects through presynaptic and postsynaptic processes
Rationale: Baclofen is a GABAb receptor AGONIST in the DORSAL horn of the spinal cord. Baclofen also provides analgesic effects through postsynaptic G-proteins and presynaptic inhibition of glutamate and substance P.
- Prior to surgery, the SRNA is reviewing Mrs. Wilson’s labs and notices that her total serum concentration of calcium is 7.8 mg/dL (low), but her ionized calcium is 4.8 mg/dL (normal) and she exhibits no signs of hypocalcemia. What other clinical conditions would the SRNA expect Mrs. Wilson’s lab work to exhibit that would explain this calcium shift? CHOOSE 2
a. hypomagnesemia
b. hyperkalemia
c. hypophosphatemia
d. hypoalbuminemia
C & D HYPOPHOSPHATEMIA AND HYPOALBUMINEMIA
Rationale: Total plasma calcium consists of (1) calcium bound to albumin, (2) calcium complexed with citrate and phosphorus ions, and (3) freely diffusible ionized calcium. As would be expected, total plasma calcium decreases with low serum albumin and with hypophosphatemia. It is the ionized calcium, and not the total plasma calcium, that produces the physiologic effects of calcium. Therefore, hypoalbuminemia and hypophosphatemia typically are not associated with signs of hypocalcemia.
- Patient X comes in for YZ surgery. When reviewing Patient X chart, you notice that Patient X has a history of seizures and is on Carbamazepine for management of their seizures. Which 3 medications should you avoid administering to prevent facilitating Carbamazepine toxicity?
A. Diltiazem
B. Heparin
C. Erythromycin
D. Cimetidine
A, C, D
DILTIAZEM, ERYTHORMYCIN, & CIMETIDINE
- During the postoperative period what drugs should be avoided when treating nausea for a patient with Parkinson’s disease? Choose 2
a. Promethazine
b. Ondansetron
c. Dramamine
d. Metoclopramide
e. Propofol
A & D
PROMETHAZINE AND METOCLOPRAMIDE
1. Rationale: Parkinson’s patients should avoid Dopamine receptor antagonist antiemetics such as Prochlorperazine (Compazine), Promethazine (Phenergan), and Metoclopramide (Reglan) because they can worsen the symptoms of Parkinson’s disease.
- When reviewing the patient history and lab results, the SRNA discovers that the patient has liver impairment but still needs his antiepileptic drug. What is the safest drug for the patient with liver impairment would an astute SRNA recommend?
A. Lamotrigine
B. Phenobarbital
C. Levetiracetam
D. Valproic acid
C - LEVETIRACETAM
The pharmacokinetic profile of levetiracetam is favorable, with the absence of hepatic metabolism and minimal protein binding (Flood pg 345). It is thus excreted by the Kidney and not metabolized by the liver.
- A 60-year-old female patient with a history of Diabetes Mellitus and Coronary Artery Disease is started on a continuous Epinephrine infusion. The provider anticipates that the patient may have lab values that exhibit which of the following effects of this sympathomimetic drug ? (Choose 2)
a. Hyperglycemia
b. Hyperkalemia
c. Hypokalemia
d. Hypotension
e. Hypoglycemia
A & C
HYPERGLYCEMIA & HYPOKALEMIA
Rationale: Epinephrine induced hypokalemia may contribute to cardiac dysrhythmias which can stimulate the sympathetic nervous system. Conversely, it also may stimulate the release of potassium from the liver, tending to offset the decrease in extracellular concentration of potassium produced by entrance into the skeletal muscle. Infusions of epinephrine usually increase concentrations of glucose, cholesterol, phospholipids, and low density lipoproteins.
- Patient X has a history of Parkinson’s Disease. The patient has just started taking their prescription of Levodopa. Knowing the most common side effects of Levodopa in the first few weeks, what would be the greatest concern for this patient?
a. Hypertension
b. Constipation
c. Falls
d. Depression
FALLS
- The patient was experiencing hypotension during the case, so you administered Phenylephrine. You miscalculated the dose to administer and now the patient is experiencing a hypertensive crisis. The blood pressure is not coming down on its own. Which medication will you NOT give to the patient?
a. Nitroglycerin
b. Nitroprusside
c. Metoprolol
d. Phentolamine
METOPROLOL
beta-1 receptor blockers are contraindicated in the treatment of Phenylephrine induced hypertensive crisis because they reduce CO and can cause cardiac collapse. Vasodilating drugs such as nitroprusside or nitroglycerin may be helpful as well as Phentolamine.
- Which of the following does the SRNA know to be true regarding epilepsy with pregnant women? Choose two.
a. Significant teratogenicity can occur within the first 8 weeks of pregnancy if harmful antiepileptic drugs are taken.
b. Lamotrigine and valproate carry more than double the risk of giving birth to a fetus with a congenital malformation.
c. Clobazam is safe to administer during labor.
d. The hypoalbuminemia associated with pregnancy is due to a progressive increase in central volume leading to a toxic therapeutic plasma concentration.
A & C
a. Significant teratogenicity can occur within the first 8 weeks of pregnancy if harmful antiepileptic drugs are taken.
c. Clobazam is safe to administer during labor.
Rationale: Significant teratogenicity can happen if medications are given within the first 8 weeks of pregnancy. Carbamazepine and valproate have more than double the risk of fetus with congenital malformations. Lamotrigine has rates of congenital malformation comparable to the general population. Clobazam may be added as needed, especially during labor. In pregnancy, hypoalbuminemia is due to a progressive increase in central volume which offsets the effect of hypoalbuminemia.
- The SRNA knows that giving a standard dose of Phenytoin to which of the following patients can have the potential for toxicity? (SELECT 3)
a.) The patient in the Stepdown Unit with hepatic failure
b.) The malnourished patient in the ICU who is septic and on a Norepinephrine drip
c.) The patient that is in the PACU post craniectomy
d.) The patient that is in the ICU with Renal Failure
A, B, & D
a.) The patient in the Stepdown Unit with hepatic failure
b.) The malnourished patient in the ICU who is septic and on a Norepinephrine drip
d.) The patient that is in the ICU with Renal Failure
Rational: Patients that are malnourished, has hepatic failure, or has renal failure all run the risk for hypoalbuminemia. Norepinephrine can also cause a loss of protein-free fluid into the extracellular space.
- Which of the following chronic use of the medications should not be discontinued before surgery? Choose two.
a) Levodopa
b) Isoniazid
c) Cimetidine
d) Baclofen
A & D
LEVODOPA & BACLOFEN
A hospitalized 60 year old male patient with a history of parkinson’s disease has been
taking levodopa for a year for the management of his symptoms and is scheduled for
gastric surgery this evening. When reviewing this patient’s chart and performing the
pre-anesthesia assessment, what lab results and/or assessments would the SRNA expect to
see related to levodopa? (Choose 3)
a) A positive ketoacidosis test.
b) Black urine in the patient’s urinal.
c) The patient reports nausea.
d) Elevated liver transaminase concentration.
e) The patient reports stopping all routine meds in preparation for surgery.
A, B, D
a) A positive ketoacidosis test.
b) Black urine in the patient’s urinal.
d) Elevated liver transaminase concentration.
RATIONALE: Urinary metabolites of levodopa cause false positive ketoacidosis test and turn urine red then black upon exposure to air. Increased liver transaminase concentrations occasionally occur with levodopa. Nausea is a symptom of levodopa only within the first few weeks of taking it and this medication should not be discontinued before surgery, so these would be incorrect.