Clinical Nurse Specialist Advanced Pharmacology

Question 1

A 70-year-old patient on warfarin for atrial fibrillation is admitted for pneumonia.
The patient develops QTc prolongation (QTc 520 ms) on the cardiac monitor.
Which antibiotic should the CNS recognize as most likely contributing to QT prolongation?

Accepted Answer

Azithromycin

Answer

Amoxicillin-clavulanate

Answer

Cephalexin

Answer

Trimethoprim-sulfamethoxazole

Question 2

A patient with severe sepsis requires vasopressor support. Norepinephrine has been initiated. The intensivist is considering adding vasopressin. What is the primary pharmacological rationale for vasopressin use in septic shock?

Accepted Answer

Vasopressin acts on V1 receptors independently of adrenergic receptors, compensating for relative vasopressin deficiency in septic shock

Answer

Vasopressin is a more potent alpha-1 agonist than norepinephrine at equivalent doses

Answer

Vasopressin has positive inotropic effects that improve cardiac output in septic shock

Answer

Vasopressin is preferred in septic shock because it does not increase myocardial oxygen demand

Question 3

A 65-year-old patient with CKD stage 4 (GFR 22 mL/min) requires pain management after total knee replacement. Which opioid selection and dosing consideration is most appropriate?

Accepted Answer

Hydromorphone at reduced doses with extended dosing intervals is safer than morphine in significant renal impairment

Answer

Morphine is preferred because it has no active metabolites in renal failure

Answer

Codeine is appropriate for moderate pain because it requires renal dose adjustment only above 75 years

Answer

Meperidine is preferred for post-operative pain because it avoids the constipation of other opioids

Question 4

A patient on chronic prednisone 20 mg daily for rheumatoid arthritis requires emergency appendectomy. What is the critical perioperative pharmacological concern?

Accepted Answer

Hypothalamic-pituitary-adrenal (HPA) axis suppression requiring stress-dose steroids

Answer

Risk of postoperative bleeding due to prednisone's antiplatelet effects

Answer

Increased risk of prednisone toxicity due to surgical anesthesia interactions

Answer

Need to discontinue prednisone 48 hours preoperatively to prevent wound dehiscence

Question 5

A CNS reviewing a patient's medication list notes the patient takes simvastatin 80 mg and has been newly prescribed clarithromycin for H. pylori. What is the critical drug interaction concern?

Accepted Answer

Clarithromycin inhibits CYP3A4, dramatically increasing simvastatin levels and risk of rhabdomyolysis

Answer

Clarithromycin reduces simvastatin efficacy by inducing CYP3A4 metabolism

Answer

The combination increases clarithromycin levels, requiring dose reduction of the antibiotic

Answer

There is no clinically significant interaction between these two medications

Question 6

A patient in the ICU requires sedation management. The CNS is implementing the ABCDEF bundle. Which sedation agent is most appropriate per current evidence for mechanically ventilated patients, and what is the preferred sedation target?

Accepted Answer

Dexmedetomidine or propofol targeting light sedation (RASS -1 to 0) per PADIS guidelines

Answer

Propofol targeting deep sedation (RASS -4 to -5) to ensure patient comfort

Answer

Benzodiazepines (lorazepam) targeting moderate sedation (RASS -2 to -3) as standard of care

Answer

Ketamine for analgesia-first sedation targeting complete dissociation from environment