Anesthesiology
1 questionsA patient with mild to moderate renal failure requires reversal of muscle relaxation induced by vecuronium. Which of the following drugs is appropriate for this purpose?
NEET-PG 2024 - Anesthesiology NEET-PG Practice Questions and MCQs
Question 181: A patient with mild to moderate renal failure requires reversal of muscle relaxation induced by vecuronium. Which of the following drugs is appropriate for this purpose?
- A. Physostigmine
- B. Rivastigmine
- C. Sugammadex (Correct Answer)
- D. Succinylcholine
Explanation: ***Sugammadex*** - **Sugammadex** is a modified gamma-cyclodextrin that forms a tight, water-soluble complex with **steroidal non-depolarizing neuromuscular blocking agents** like vecuronium, effectively encapsulating and inactivating them. - Its elimination is primarily renal, but even in **mild to moderate renal failure**, its rapid binding to vecuronium and lack of active metabolites make it a safe and effective choice for reversal. *Physostigmine* - **Physostigmine** is an anticholinesterase that indirectly increases acetylcholine at the neuromuscular junction, but it is not commonly used for reversing **neuromuscular blockade** due to its widespread muscarinic and nicotinic effects. - It can cause significant side effects like **bradycardia**, **bronchospasm**, and increased secretions, and its efficacy for non-depolarizing blockers is limited. *Rivastigmine* - **Rivastigmine** is an **acetylcholinesterase inhibitor** primarily used in the treatment of **Alzheimer's disease** and Parkinson's disease dementia. - It does not have a role in reversing neuromuscular blockade induced by vecuronium. *Succinylcholine* - **Succinylcholine** is a **depolarizing neuromuscular blocker** itself, causing muscle relaxation rather than reversing it. - It would prolong paralysis rather than reverse the effects of vecuronium.
OB/GYN
1 questionsA woman at 8 weeks of gestation is diagnosed with hyperthyroidism. Which of the following is the most appropriate treatment option?
NEET-PG 2024 - OB/GYN NEET-PG Practice Questions and MCQs
Question 181: A woman at 8 weeks of gestation is diagnosed with hyperthyroidism. Which of the following is the most appropriate treatment option?
- A. Methimazole
- B. Carbimazole
- C. Propylthiouracil (Correct Answer)
- D. Radioactive iodine
Explanation: ***Propylthiouracil*** - **Propylthiouracil (PTU)** is the preferred treatment for hyperthyroidism in the **first trimester** of pregnancy due to a lower risk of teratogenic effects compared to methimazole. - While PTU carries a risk of **liver toxicity**, its use is generally favored in early pregnancy to avoid the more severe potential fetal abnormalities associated with other antithyroid drugs during this critical developmental period. *Methimazole* - **Methimazole** is associated with a specific pattern of birth defects, including **aplasia cutis congenita** (scalp defects) and **esophageal/choanal atresia**, when used during the first trimester. - It is generally preferred in the **second and third trimesters** due to a lower risk of maternal hepatotoxicity compared to PTU. *Carbimazole* - **Carbimazole** is a **prodrug** that is metabolized to methimazole; therefore, it carries the same teratogenic risks as methimazole in the first trimester. - Its use during early pregnancy is generally avoided for the same reasons as methimazole. *Radioactive iodine* - **Radioactive iodine (RAI)** is **contraindicated** in pregnancy because it crosses the placenta and can cause **fetal hypothyroidism** and irreversible destruction of the fetal thyroid gland. - It is an effective treatment for hyperthyroidism outside of pregnancy but is never used during gestation.
Obstetrics and Gynecology
1 questionsA woman at 30 weeks of gestation is diagnosed with deep vein thrombosis (DVT). Which of the following is the most appropriate treatment for this patient?
NEET-PG 2024 - Obstetrics and Gynecology NEET-PG Practice Questions and MCQs
Question 181: A woman at 30 weeks of gestation is diagnosed with deep vein thrombosis (DVT). Which of the following is the most appropriate treatment for this patient?
- A. Warfarin
- B. Low Molecular Weight Heparin (LMWH) (Correct Answer)
- C. Apixaban
- D. Fondaparinux
Explanation: ***Low Molecular Weight Heparin (LMWH)*** - **LMWH** is the preferred anticoagulant for DVT during pregnancy because it does **not cross the placenta**, making it safe for the fetus. - It also has a **predictable anticoagulant response** and a lower risk of **heparin-induced thrombocytopenia (HIT)** compared to unfractionated heparin. *Warfarin* - **Warfarin is teratogenic**, especially during the first trimester, and can cause **fetal warfarin syndrome**, which includes skeletal and central nervous system abnormalities. - It can also lead to **fetal bleeding** and miscarriage at any stage of pregnancy. *Apixaban* - **Apixaban** is a **direct oral anticoagulant (DOAC)**, and its safety in pregnancy has not been established. - There is insufficient data regarding its **placental transfer** and potential fetal effects, making its use generally contraindicated in pregnant women. *Fondaparinux* - While **fondaparinux** is an indirect Factor Xa inhibitor and might be considered in cases of heparin allergy or intolerance, its **safety profile in pregnancy is not as well-established** as LMWH. - It is generally reserved for situations where LMWH cannot be used, and its use requires careful consideration due to limited data.
Pharmacology
7 questionsWhich of the following cardioselective betablockers has been shown to decrease mortality in patients with congestive heart failure?
Aprepitant is a drug used in the treatment of some cases of chemotherapy-induced nausea and vomiting. What is the mechanism of action of this drug?
Which of the following is an inclusion criterion for the shorter bedaquiline regimen in the treatment of tuberculosis?
A patient presents with hypertension and has a history of renal stones, along with several episodes of renal colic. Which diuretic is the most appropriate to use?
Which of the following is the most appropriate treatment for an overactive bladder in a patient with dementia?
Which of the following statements regarding the patch shown in the figure is correct?
Lidocaine is used in a loading dose for the treatment of arrhythmias. The loading dose of this drug depends upon which of the following factors?
NEET-PG 2024 - Pharmacology NEET-PG Practice Questions and MCQs
Question 181: Which of the following cardioselective betablockers has been shown to decrease mortality in patients with congestive heart failure?
- A. Propranolol
- B. Bisoprolol (Correct Answer)
- C. Labetalol
- D. Pindolol
- E. Atenolol
Explanation: ***Bisoprolol*** - **Bisoprolol** is a highly cardioselective beta-1 blocker that has been extensively studied and proven to reduce mortality and morbidity in patients with **systolic congestive heart failure**. - It is one of the **"big three" beta-blockers** (along with **carvedilol** and **metoprolol succinate**) recommended for chronic heart failure management by major cardiology guidelines, supported by the **CIBIS-II trial**. *Atenolol* - **Atenolol** is a cardioselective beta-1 blocker commonly used for hypertension and angina. - Despite being cardioselective, it has **not been shown to reduce mortality** in patients with chronic heart failure and is generally **not recommended** for this indication due to lack of supportive clinical trial evidence. *Propranolol* - **Propranolol** is a non-selective beta-blocker that blocks both beta-1 and beta-2 receptors. - While effective for conditions like angina and arrhythmias, it is generally **not recommended** for chronic heart failure due to its non-selectivity and lack of evidence for mortality reduction in this specific patient population. *Labetalol* - **Labetalol** is an alpha- and beta-adrenergic blocker, often used in hypertensive emergencies and for managing hypertension in pregnancy. - It is **not indicated** for mortality reduction in chronic heart failure due to its different pharmacological profile and lack of clinical trial evidence supporting its use for this purpose. *Pindolol* - **Pindolol** is a non-selective beta-blocker with **intrinsic sympathomimetic activity (ISA)**, meaning it partially stimulates beta-receptors while blocking the effects of norepinephrine and epinephrine. - Beta-blockers with ISA are generally **contraindicated** in heart failure because their partial agonist activity can potentially worsen myocardial function, and they have not shown any mortality benefit.
Question 182: Aprepitant is a drug used in the treatment of some cases of chemotherapy-induced nausea and vomiting. What is the mechanism of action of this drug?
- A. NK1 antagonist (Correct Answer)
- B. NK3 antagonist
- C. NK1 agonist
- D. NK2 agonist
- E. NK2 antagonist
Explanation: ***NK1 antagonist*** - **Aprepitant** is a selective, high-affinity antagonist of the **neurokinin 1 (NK1) receptor**, which is activated by **substance P**. - By blocking NK1 receptors in the brainstem's **vomiting center**, aprepitant prevents nausea and vomiting, especially in chemotherapy-induced cases. - Aprepitant is particularly effective for **acute and delayed** chemotherapy-induced nausea and vomiting (CINV). *NK3 antagonist* - While **neurokinin 3 (NK3) receptors** are present in the central nervous system, their specific role in chemotherapy-induced nausea and vomiting is less prominent. - Aprepitant does not primarily target NK3 receptors; its antiemetic action is mediated through NK1 blockade. *NK1 agonist* - An **NK1 agonist** would activate the NK1 receptor, potentially *inducing* nausea and vomiting, which is the opposite of the desired therapeutic effect of aprepitant. - Agonists are typically used to stimulate a receptor, not block it as is done with aprepitant. *NK2 antagonist* - **Neurokinin 2 (NK2) receptors** are also part of the tachykinin receptor family, but they are not the primary target for antiemetic drugs like aprepitant. - While NK2 receptors play roles in smooth muscle contraction and inflammation, blocking them is not the mechanism by which aprepitant prevents nausea and vomiting. - Aprepitant's antiemetic efficacy is specifically due to **NK1 receptor antagonism**. *NK2 agonist* - **Neurokinin 2 (NK2) receptors** are also part of the tachykinin receptor family, but they are not the primary target for antiemetic drugs like aprepitant. - Activating NK2 receptors would not provide the antiemetic effect seen with aprepitant, as NK1 receptor antagonism is crucial.
Question 183: Which of the following is an inclusion criterion for the shorter bedaquiline regimen in the treatment of tuberculosis?
- A. Extrapulmonary TB like Tubercular meningitis
- B. Rifampicin resistance with both KatG and inhA mutation
- C. Rifampicin-sensitive TB
- D. Rifampicin-resistant but fluoroquinolone-sensitive TB (Correct Answer)
- E. Extensively drug-resistant TB (XDR-TB)
Explanation: ***Rifampicin-resistant but fluoroquinolone-sensitive TB*** - The **shorter bedaquiline regimen** is specifically recommended for patients with **rifampicin-resistant tuberculosis** who are also sensitive to fluoroquinolones. - This regimen optimizes treatment outcomes by leveraging the effectiveness of both bedaquiline and a potent fluoroquinolone against sensitive strains. *Extrapulmonary TB like Tubercular meningitis* - The shorter bedaquiline regimen is generally not recommended for severe forms of **extrapulmonary TB**, especially those involving the **central nervous system**, due to concerns about drug penetration and efficacy. - These cases often require longer, individualized regimens with stronger central nervous system penetration. *Rifampicin resistance with both KatG and inhA mutation* - The presence of both **KatG** and **inhA mutations** indicates high-level **isoniazid resistance**, which is not the primary criterion for selecting the shorter bedaquiline regimen. - While these mutations are important for guiding isoniazid use, the core inclusion for this regimen is **rifampicin resistance** and **fluoroquinolone sensitivity**. *Rifampicin-sensitive TB* - Patients with **rifampicin-sensitive TB** are usually treated with standard first-line regimens that do not include bedaquiline, as their disease is susceptible to more conventional therapies. - The shorter bedaquiline regimen is reserved for drug-resistant cases, particularly those with rifampicin resistance. *Extensively drug-resistant TB (XDR-TB)* - While **XDR-TB** patients may receive bedaquiline, they typically require **longer, individualized regimens** rather than the shorter standardized regimen. - The shorter bedaquiline regimen is primarily indicated for **rifampicin-resistant TB** that is **fluoroquinolone-sensitive**, whereas XDR-TB involves resistance to both fluoroquinolones and injectable agents, requiring more complex treatment approaches.
Question 184: A patient presents with hypertension and has a history of renal stones, along with several episodes of renal colic. Which diuretic is the most appropriate to use?
- A. Furosemide
- B. Hydrochlorothiazide (Correct Answer)
- C. Ethacrynic acid
- D. Spironolactone
- E. Indapamide
Explanation: **Hydrochlorothiazide** - **Thiazide diuretics** like hydrochlorothiazide reduce urinary calcium excretion, which is beneficial in patients with a history of **calcium renal stones**. - This effect helps prevent the recurrence of renal stones while also treating hypertension. - Among thiazide and thiazide-like diuretics, hydrochlorothiazide has the **most established evidence** for preventing calcium stone recurrence. *Furosemide* - Furosemide is a **loop diuretic** that increases urinary calcium excretion, which would exacerbate the risk of renal stone formation. - While effective for hypertension, its effect on calcium makes it unsuitable for this patient. *Ethacrynic acid* - Ethacrynic acid is also a **loop diuretic** with similar effects to furosemide, including increasing urinary calcium excretion. - This makes it an inappropriate choice for a patient with a history of renal stones. *Spironolactone* - Spironolactone is a **potassium-sparing diuretic** that works by antagonizing aldosterone, primarily affecting sodium and potassium excretion. - It does not significantly impact urinary calcium excretion in a way that would prevent calcium renal stones, nor is it a first-line agent for hypertension with co-existing renal stones. *Indapamide* - Indapamide is a **thiazide-like diuretic** with some calcium-retaining properties, but it is less effective than hydrochlorothiazide in reducing calcium excretion. - While it can be used for hypertension, **hydrochlorothiazide is preferred** specifically for preventing calcium stone recurrence due to stronger evidence and greater effect on reducing urinary calcium.
Question 185: Which of the following is the most appropriate treatment for an overactive bladder in a patient with dementia?
- A. Tolterodine (Correct Answer)
- B. Mirabegron
- C. Behavioral therapy/bladder training
- D. Oxybutynin
- E. Trospium
Explanation: ***Tolterodine*** - **Tolterodine** is a **muscarinic antagonist** that blocks acetylcholine receptors in the bladder, reducing detrusor muscle contractions and overactive bladder symptoms. - Unlike some other anticholinergics like oxybutynin, it has a **lower propensity to cross the blood-brain barrier** and thus a reduced risk of exacerbating cognitive impairment in patients with dementia. *Mirabegron* - **Mirabegron** is a **beta-3 adrenergic agonist** that relaxes the detrusor muscle, increasing bladder capacity. - While it has a different mechanism of action and is less likely to cause anticholinergic cognitive side effects than older anticholinergics, it can still cause **hypertension** and **tachycardia**, which may be problematic in elderly patients with comorbidities. *Behavioral therapy/bladder training* - **Behavioral therapy** and **bladder training** are important first-line treatments for overactive bladder. - However, for patients with **dementia**, cognitive impairment often makes adherence to and understanding of these complex therapies challenging or impossible without significant caregiver support. *Oxybutynin* - **Oxybutynin** is an **anticholinergic drug** that is effective for overactive bladder. - However, it has a **high affinity for muscarinic receptors** in the brain and readily crosses the blood-brain barrier, significantly increasing the risk of **cognitive impairment, confusion, and delirium** in elderly patients, especially those with pre-existing dementia. *Trospium* - **Trospium** is a **quaternary amine anticholinergic** that is hydrophilic and has minimal blood-brain barrier penetration. - While theoretically safer than oxybutynin in terms of CNS effects, it has **lower bladder selectivity** compared to tolterodine and may cause more peripheral anticholinergic side effects (dry mouth, constipation).
Question 186: Which of the following statements regarding the patch shown in the figure is correct?
- A. It is an equal mixture of local anesthetics.
- B. Excessive use can result in methemoglobinemia. (Correct Answer)
- C. 5 ml of a 5 percent mixture contains 50 mg of lignocaine.
- D. It contains lignocaine and ropivacaine in a ratio of 50 percent each.
- E. It should be applied for at least 2 hours before minor procedures.
Explanation: ***Excessive use can result in methemoglobinemia.*** - The patch shown is likely an **EMLA patch**, which contains **lidocaine** and **prilocaine**. Excessive absorption of prilocaine, especially with large doses or prolonged application, can lead to the formation of **methemoglobinemia**. - **Prilocaine** is metabolized into **ortho-toluidine**, which is an oxidizing agent that can convert hemoglobin to methemoglobin, reducing the blood's oxygen-carrying capacity. *It is an equal mixture of local anesthetics.* - The EMLA patch is a 1:1 mixture of **lidocaine** and **prilocaine**, but the claim that it contains "an equal mixture of local anesthetics" is vague and could imply other compositions not specific to EMLA. - While it's an equal ratio of two specific local anesthetics, the option's wording is not precise enough to be the *most correct* statement. *5 ml of a 5 percent mixture contains 50 mg of lignocaine.* - A 5% solution means 5 grams (5000 mg) per 100 ml. Therefore, 1 ml contains 50 mg of lignocaine. - Thus, 5 ml of a 5% mixture would contain 250 mg of **lignocaine**, not 50 mg. This statement is mathematically incorrect. *It contains lignocaine and ropivacaine in a ratio of 50 percent each.* - **EMLA patches** contain **lidocaine** (lignocaine) and **prilocaine**, not ropivacaine. - While it is a 50% concentration for each active ingredient, the specific combination of local anesthetics mentioned in this option is incorrect. *It should be applied for at least 2 hours before minor procedures.* - For most minor procedures, **EMLA cream** typically requires **30-60 minutes** of application time to achieve adequate topical anesthesia. - While longer application times (up to 2 hours) may enhance depth of anesthesia for certain procedures, stating that it "should be applied for at least 2 hours" is excessive and not a standard recommendation for minor procedures.
Question 187: Lidocaine is used in a loading dose for the treatment of arrhythmias. The loading dose of this drug depends upon which of the following factors?
- A. Clearance
- B. Volume of distribution (Correct Answer)
- C. Half-life
- D. Bioavailability
- E. Elimination rate constant
Explanation: ***Volume of distribution*** - The **loading dose** of a drug is primarily determined by its **volume of distribution (Vd)** and the **target plasma concentration**. - A larger **Vd** means the drug distributes widely into tissues, requiring a larger loading dose to achieve the desired concentration in the central compartment. *Clearance* - **Clearance** dictates the **maintenance dose** needed to sustain a steady-state concentration once the loading dose has been administered. - It reflects the rate at which the drug is eliminated from the body, not how much is initially needed to fill the distribution volume. *Half-life* - **Half-life** determines the **time required to reach steady-state** and the **dosing interval** for maintaining therapeutic concentrations. - While related to clearance and Vd, it does not directly determine the magnitude of the initial loading dose itself. *Bioavailability* - **Bioavailability** is the fraction of administered drug that reaches the systemic circulation in an unchanged form. - It influences the oral dose required to achieve a certain plasma concentration, but the concept of loading dose is typically considered for the intravenous route where bioavailability is 100%. *Elimination rate constant* - The **elimination rate constant (ke)** describes the rate of drug elimination and is related to clearance and volume of distribution (ke = Cl/Vd). - Like clearance, it determines the **maintenance dose** and dosing frequency, not the initial loading dose required to achieve therapeutic levels.