Nokea
If you inject a drug with a pH of 6.5 and pka of 8.1 into a tissue with a pH of 7.4, to what extent would you expect this drug to be ionized in the tissue?
- A. over 50%
- B. 50%
- C. under 50%
- D. 100%
Correct Answer: A
Rationale: The percentage of ionization of a weak acid or base can be estimated using the Henderson-Hasselbalch equation:
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Which of the following 'overdoses' is most commonly associated with respiratory alkalosis, but when more severe a metabolic acidosis?
- A. Methanol
- B. Lead
- C. Paracetamol
- D. Salicylate
Correct Answer: D
Rationale: Overdose toxicities differ in acid-base effects. Methanol causes metabolic acidosis via formic acid, not respiratory alkalosis. Lead poisoning leads to anemia or neurologic issues, rarely acid-base shifts. Paracetamol overdose induces lactic acidosis from liver failure, not respiratory changes initially. Salicylate (e.g., aspirin) overdose stimulates the respiratory center early, causing hyperventilation and respiratory alkalosis (low pCO2), but severe cases add metabolic acidosis (high anion gap) from uncoupled oxidative phosphorylation and lactic acid buildup. Codeine, an opioid, depresses respiration, causing acidosis, not alkalosis. Salicylate's dual pattern is distinctive, requiring urgent recognition—initial alkalosis shifts to acidosis as toxicity worsens, guiding bicarbonate or dialysis treatment.
The nurse manages care for several clients receiving hormone replacement therapy (HRT). What will the priority assessment by the nurse include as related to side effects?
- A. Pain in the calf
- B. Decreased libido
- C. Low-back pain
- D. Chronic fatigue
Correct Answer: A
Rationale: HRT increases clotting risk, making calf pain a priority due to potential DVT, a life-threatening side effect. Libido , back pain , and fatigue are less urgent. A ensures safety, aligning with HRT risks, making it the priority.
The pregnant patient tells the nurse that her prescribed medication is not as effective as it was before her pregnancy. What is the best response by the nurse?
- A. This is because your blood volume has increased
- B. Tell me how you have been taking your medication
- C. This is because your baby is receiving part of the medication
- D. Maybe the medication has expired; check the label
Correct Answer: A
Rationale: Pregnancy increases blood volume (50% more), diluting drugs, reducing efficacy-e.g., lower concentration per unit volume, a pharmacokinetic shift. Asking about administration checks adherence, not cause. Baby receiving drug is unlikely-placental transfer varies. Expiration is a guess, not tied to pregnancy. Blood volume explains the change, addressing her concern.
The nurse administers IV push hydralazine (Apresoline) to a client with severe hypertension. Which assessment finding requires immediate action?
- A. Blood pressure of 140/90 mmHg
- B. Heart rate of 110 beats per minute
- C. Headache
- D. Flushing
Correct Answer: B
Rationale: Hydralazine, a vasodilator, lowers blood pressure but triggers reflex tachycardia. A heart rate of 110 bpm indicates significant compensation, risking ischemia or strain, requiring immediate action (e.g., slowing infusion, notifying physician). BP of 140/90 is improved, not critical. Headache and flushing are expected from vasodilation, less urgent. Tachycardia's potential to destabilize circulation, especially in severe hypertension, aligns with hydralazine's pharmacology'arteriolar relaxation prompts sympathetic response. This finding demands swift intervention to prevent cardiovascular collapse, making B the priority over manageable side effects.
Enteric coated acetylsalicylic acid has been prescribed for a patient to treat chronic arthritis. The patient calls the clinic nurse because of gagging and difficulty swallowing the tablets. What response would the nurse give to the patient?
- A. Crush the tablets and mix with juice or food'
- B. I’ll notify the healthcare provider for a medication change'
- C. Open the tablet and mix the contents with food'
- D. Swallow the tablets with large amounts of water or milk'
Correct Answer: D
Rationale: Enteric-coated tablets should not be crushed or opened, as this disrupts their protective coating and can cause gastric irritation. The patient should be instructed to swallow the tablets whole with plenty of water or milk. Crushing (A) or opening the tablets (C) is inappropriate. Notifying the healthcare provider (B) may be necessary if the patient cannot tolerate the medication.