A local municipality is alerted that low doses of carbon tetrachloride have been dumped into the drinking water. A public health alert is transmitted to all residents of this town. Which of the following signs and symptoms should these residents be aware of?

Correct Answer: C

Rationale: Carbon tetrachloride exposure causes nausea , reflecting GI and hepatic toxicity. Convulsions and stupor occur with high doses. Eye irritation and vomiting (E) are less specific. Low-dose ingestion aligns with nausea as a primary symptom.

Correct Answer: C

Rationale: Tranexamic acid is an antifibrinolytic agent, which means it works by inhibiting the breakdown of blood clots. It does this by blocking the activation of plasmin, which is responsible for breaking down fibrin clots. This action helps in promoting clot stability and reducing bleeding. Tranexamic acid is commonly used to treat or prevent excessive bleeding in various conditions, such as heavy menstrual bleeding, surgery, trauma, and certain medical procedures.

Correct Answer: A

Rationale: ACE inhibitors, such as enalapril and lisinopril, work by blocking the enzyme angiotensin-converting enzyme (ACE), which is responsible for converting angiotensin I into angiotensin II. By inhibiting this conversion, ACE inhibitors prevent the vasoconstrictor and aldosterone-stimulating effects of angiotensin II at the receptor sites. This leads to vasodilation, decreased blood pressure, and reduced aldosterone secretion. This mechanism of action makes ACE inhibitors an important class of medications for managing conditions such as hypertension, heart failure, and chronic kidney disease.

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.

Correct Answer: A

Rationale: The percentage of ionization of a weak acid or base can be estimated using the Henderson-Hasselbalch equation:

Correct Answer: D

Rationale: Depo-Provera, a progestin injection, provides contraception by inhibiting ovulation for 3 months , requiring re-administration every 12 weeks. This duration is based on its pharmacokinetic profile, ensuring reliable hormone levels. Two months underestimates, risking unprotected gaps. Six months or 1 year overestimate, reducing efficacy mid-cycle. The nurse's accurate response (D) educates the client on timing, ensuring adherence and preventing unintended pregnancy, aligning with clinical standards for injectable contraceptives.

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.

Correct Answer: C

Rationale: A common side effect of Heparin, which is an anticoagulant medication, is the risk of bleeding. Heparin works by preventing the formation of blood clots, which can lead to a bleeding risk as it inhibits the normal clotting process. Patients taking Heparin should be monitored closely for signs of bleeding, such as easy bruising, prolonged bleeding from minor cuts, or blood in the urine or stools. It is important for healthcare providers to closely monitor patients on Heparin therapy and adjust the dosage as needed to minimize the risk of excessive bleeding.

Correct Answer: C

Rationale: Seasonal affective disorder (SAD) ties depression to winter-less light, per psychiatry-unlike baby blues (postpartum), bipolar (cycles), or OCD (obsessions). SAD's seasonal link defines it, matching symptoms.