بنك أسئلة التخدير

اقرأ أسئلة عيّنة بنك أسئلة التخدير

1. 1.Preoperative application of scopolamine patch to prevent postoperative nausea and vomiting should be avoided in

   • أ.Female, 35 years old
   • ب.Smoker, 20 years old
   • ج.Patient with a blood pressure of 160/96 mm Hg
   • د.Male, 70 years oldإجابة صحيحة

   لماذا: Scopolamine is an antimuscarinic with central anticholinergic effects, so it is best avoided in the elderly, who are most susceptible to confusion, sedation, and delirium; a 70-year-old male is therefore the patient in whom it should be avoided. Anticholinergics can also precipitate glaucoma and urinary retention, risks that rise with age.

2. 2.Which of the following drugs is least likely to be effective for prophylaxis for postoperative nausea and vomiting?

   • أ.Ondansetron
   • ب.Scopolamine patch
   • ج.Aprepitant
   • د.Metoclopramideإجابة صحيحة

   لماذا: Metoclopramide is a relatively weak antiemetic for PONV prophylaxis at standard doses and is the least effective listed. Ondansetron (5-HT3 antagonist), scopolamine, and aprepitant (NK-1 antagonist) all have well-established prophylactic efficacy.

3. 3.Famotidine, when used for stress ulcer prophylaxis, must be avoided preoperatively in which of the following patients?

   • أ.Patients with replaced mitral valve on warfarin
   • ب.Patients with idiopathic thrombocytopenic purpura (ITP) for splenectomyإجابة صحيحة
   • ج.Patients with achalasia cardia for esophageal myotomy
   • د.Patients with a history of coronary stenting on aspirin

   لماذا: Famotidine is an H2-receptor antagonist used for stress-ulcer/aspiration prophylaxis, but it should be avoided in ITP patients because H2 blockers can cause thrombocytopenia, worsening an already low platelet count before splenectomy.

4. 4.Which of the following drugs antagonizes substance P in the central nervous system and is used as premedication to prevent postoperative nausea and vomiting?

   • أ.Palonosetro
   • ب.Aprepitantإجابة صحيحة
   • ج.Metoclopramide
   • د.Prochlorperazine

   لماذا: Aprepitant is a neurokinin-1 (NK-1) receptor antagonist that blocks substance P centrally, providing prolonged PONV prophylaxis. The other agents act on serotonin, dopamine, or cholinergic pathways.

5. 5.Which of the following predictors is likely to be associated with lower incidence of perioperative nausea and vomiting?

   • أ.Female gender
   • ب.Use of fentanyl for pain relief
   • ج.Patients with a history of smokingإجابة صحيحة
   • د.Patients undergoing laparoscopic surgery

   لماذا: A history of smoking is paradoxically associated with a LOWER incidence of PONV, likely from enzyme induction and altered central nervous system sensitivity. Female gender, opioid (fentanyl) use, and laparoscopic surgery all increase PONV risk.

6. 6.All of the following have an antiemetic action, except

   • أ.Promethazine
   • ب.Propofol
   • ج.Etomidateإجابة صحيحة
   • د.Haloperidol

   لماذا: Etomidate is NOT antiemetic and is actually associated with a relatively high incidence of postoperative nausea and vomiting. Propofol has antiemetic properties, and promethazine and haloperidol (a butyrophenone) both have antiemetic activity.

7. 7.Cefazolin, as a component of perioperative antimicrobial prophylaxis for surgery, must begin within what time before incision?

   • أ.Simultaneously with incision
   • ب.Within 30 minutes prior to incision
   • ج.Within 60 minutes prior to incisionإجابة صحيحة
   • د.Within 120 minutes prior to incision

   لماذا: Cefazolin and most beta-lactam surgical prophylactic antibiotics should be administered within 60 minutes before skin incision to ensure adequate tissue concentrations at the time of contamination.

8. 8.Vancomycin, as a component of perioperative antimicrobial prophylaxis for surgery, must begin within what time before incision?

   • أ.Simultaneously with incision
   • ب.Within 30 minutes prior to incision
   • ج.Within 60 minutes prior to incision
   • د.Within 120 minutes prior to incisionإجابة صحيحة

   لماذا: Vancomycin (and fluoroquinolones) require longer infusion times to avoid reactions such as red-man syndrome, so they should be started within 120 minutes before incision to achieve adequate tissue levels by the time of surgery.

9. 9.A 65-year-old male with a history of hypertension and diabetes presents to emergency department with altered sensation with a likely subdural hematoma. To assess his cardiorespiratory status, he is asked about his level of physical activity. If he is capable of performing at least which of the following activities independently, he is less likely to have significant cardiopulmonary ailment during surgery?

   • أ.Walk to washroom on level floor
   • ب.Play the accordion
   • ج.Walk one block
   • د.Climb a flight of stairsإجابة صحيحة

   لماذا: Functional capacity is assessed in METs; the ability to climb a flight of stairs represents roughly 4 METs, the threshold above which perioperative cardiac risk is considered acceptable and further cardiac testing is often unnecessary.

10. 10.In preoperative assessment of patients, physical activity is graded in terms of metabolic equivalents (METs). The value that corresponds to oxygen consumption of 1 MET in an adult is

    • أ.2 mL/kg/min
    • ب.7 mL/kg/min
    • ج.3.5 mL/kg/minإجابة صحيحة
    • د.5.5 mL/kg/min

    لماذا: By definition, 1 MET equals an oxygen consumption of approximately 3.5 mL/kg/min, the resting metabolic rate of an average adult. Functional capacity is expressed as multiples of this value.