Nokea
Antibiotics altering permeability of cell membranes are:
- A. Glycopeptides
- B. Polymyxins
- C. Tetracyclines
- D. Cephalosporins
Correct Answer: B
Rationale: The correct answer is B: Polymyxins. Polymyxins are antibiotics that work by altering the permeability of the bacterial cell membrane, leading to leakage of cellular contents and ultimately bacterial cell death. This mechanism of action is specific to polymyxins, making it the correct choice.
Incorrect Choices:
A: Glycopeptides - Glycopeptides work by inhibiting cell wall synthesis, not by altering cell membrane permeability.
C: Tetracyclines - Tetracyclines inhibit protein synthesis in bacteria, they do not target cell membrane permeability.
D: Cephalosporins - Cephalosporins interfere with cell wall synthesis, they do not directly affect cell membrane permeability.
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The following statements are true except: Unfractionated heparin:
- A. Binds to antithrombin III
- B. Inhibits the action of thrombin
- C. Is monitored in the laboratory by measurement of activated partial thromboplastin time (APTT)
- D. Is reversed by protamine sulphate
Correct Answer: d
Rationale: Unfractionated heparin enhances antithrombin III (A), inhibits thrombin (B), is monitored by APTT (C), is less effective with antithrombin deficiency (D), and is reversed by protamine (E).
Indicate an antiseizure drug, which has an impotent effect on the T-type calcium channels in thalamic neurons?
- A. Carbamazepin
- B. Lamotrigine
- C. Ethosuximide
- D. Phenytoin
Correct Answer: C
Rationale: Certainly! Ethosuximide is the correct answer because it specifically targets T-type calcium channels in thalamic neurons, effectively controlling absence seizures. Carbamazepine, Lamotrigine, and Phenytoin primarily act on sodium channels, making them ineffective in treating absence seizures. Ethosuximide's mechanism of action makes it the ideal choice for this specific type of seizure.
A patient is receiving thrombolytic therapy, and the nurse monitors the patient for adverse effects. What is the most common undesirable effect of thrombolytic therapy?
- A. Dysrhythmias
- B. Nausea and vomiting
- C. Anaphylactic reactions
- D. Internal and superficial bleeding
Correct Answer: D
Rationale: The correct answer is D: Internal and superficial bleeding. Thrombolytic therapy works by breaking down blood clots, which can lead to bleeding as a side effect. This occurs because the medication can also affect the body's ability to form clots at the site of injury. Internal and superficial bleeding are the most common and serious adverse effects of thrombolytic therapy. Dysrhythmias (choice A) are not typically associated with thrombolytic therapy. Nausea and vomiting (choice B) are common side effects of many medications, but not specifically thrombolytic therapy. Anaphylactic reactions (choice C) are rare but serious allergic reactions and are not the most common undesirable effect of thrombolytic therapy.
Tick the synthetic vasoconstrictor having an adrenomimic effect:
- A. Noradrenalin
- B. Adrenalin
- C. Phenylephrine
- D. Angiotensinamide
Correct Answer: C
Rationale: The correct answer is C: Phenylephrine. Phenylephrine is a synthetic vasoconstrictor that acts by stimulating adrenergic receptors, specifically alpha-adrenergic receptors, leading to vasoconstriction. Noradrenaline (A) and adrenaline (B) are endogenous catecholamines that also have vasoconstrictive effects but are not synthetic. Angiotensinamide (D) is not a synthetic vasoconstrictor and acts through a different mechanism involving the renin-angiotensin system. In summary, Phenylephrine is the correct choice as it is a synthetic vasoconstrictor with adrenomimetic effects, while the other options do not fit this description.
A patient who takes lithium phones the nurse at the clinic to say, “I’ve had diarrhea for 4 days. I feel weak and unsteady when I walk. My usual hand tremor has gotten worse. What should I do?” Which instruction by the nurse is appropriate?
- A. “Have someone bring you to the clinic immediately.”
- B. “Restrict food and fluids for 24 hours and stay in bed.”
- C. “Drink a large glass of water with 1 teaspoon of salt added.”
- D. “Take antidiarrheal medication hourly until the diarrhea subsides.”
Correct Answer: A
Rationale: The correct answer is A: "Have someone bring you to the clinic immediately." This is the appropriate instruction because the patient is experiencing symptoms of lithium toxicity, such as diarrhea, weakness, unsteadiness, and worsening hand tremor. Lithium toxicity is a serious condition that can lead to life-threatening complications if not treated promptly. Bringing the patient to the clinic immediately allows for proper evaluation, monitoring, and treatment by healthcare professionals.
Summary:
- Choice B: "Restrict food and fluids for 24 hours and stay in bed" is incorrect as it does not address the urgency of the situation and may worsen dehydration.
- Choice C: "Drink a large glass of water with 1 teaspoon of salt added" is incorrect as it can exacerbate the electrolyte imbalance caused by lithium toxicity.
- Choice D: "Take antidiarrheal medication hourly until the diarrhea subsides" is incorrect as it does not address the root cause of the symptoms and may delay necessary medical intervention.