Flashcards in UWorld Random facts Deck (22):
Tendency of study subjects to change their behavior as a result of their awareness that they are being studied
The fact that the a researcher's beliefs in the efficacy of treatment can potentially change the outcome
Why does a TCA overdose cause arrhythmias and how do you treat it?
Blockage of fast cardiac sodium channels, can see prolonged QRS, treat with sodium bicarbonate (increases serum pH, which favors the non-ioned form of the drug, making it less accessible to bind to sodium channels)
MOA of cyanide toxicity
Cyanide is a potent mitochondrial toxin that binds to Fe3+ in cytochrome oxidase, inhibiting the electron transport chain and halting aerobic respiration in the cell
Presentation of cyanide toxicity
Altered mental status, seizures, cardiovascular collapse, lactic acidosis, and bright red venous blood
Sx of phenylketonuria even with tyrosine supplementation
Deficiency of dihydrobiopterin reductase
Most common pathologic cause of unilateral fetal hydronephrosis is
A narrowing or kinking of the proximal ureter at the ureteropelvic junction
What does the internal laryngeal nerve do?
(CN X) Contains only sensory and autonomic fibers, mediated the affect limb of the cough reflex by carrying sensation from the mucosa superior to the vocal cords
Causes of pulsus paradoxus
Pericardial effusion, constrictive pericarditis, asthma/COPD exacerbation
When would you not want to use probenecid?
In a patient with bad renal function. It should not be used in patients at risk for nephrolithiasis or uric acid nephropathy
MOA of rasburicase
A recombinant version of urate oxidase that catalyzes the conversion of uric acid to alienation, which is 5-10 times more soluble than uric acid
Non-surgical tx for gallstone
Bile acid supplementation (e.g., ursodeoxycholic acid)
What prevents the hematogenous spread of candida?
MOA of enfuvirtide
Interacts with the p41 antigen on HIV-1 and prevents p41-mediated membrane fusion between the vision and host cells
Respiratory changes seen in ARDS
Ventilation-perfusion mismatch (causes right-to-left shunting and hypoxemia) and increased physiologic dead space (leads to decreased alveolar ventilation and hypercapnia)
Major adverse effect of amphotericin B
MOA of imiquimod
Imidazoquinolone nucleoside analog that acts as an agonist of TLR 7 and 8 and leads to activation of NF-kB. Used as an immunomodulator in the tx of genital or perianal warts/condyloma acuminata and actinic keratosis
Best indicator of severity on auscultation of mitral stenosis
Length of time between S2 and the opening snap
What factors keep a drug in the plasma compartment?
Large molecular weight, extensively bound to plasma proteins, or is highly charged
Lab values in primary hyperaldosteronism
Normal sodium (b/c of aldosterone escape), low potassium, high bicarb
Smooth muscle cell antibodies