Anesthesiology
1 questionsThe inducing agent of choice in shock -
NEET-PG 2013 - Anesthesiology NEET-PG Practice Questions and MCQs
Question 1511: The inducing agent of choice in shock -
- A. Isoflurane
- B. Ketamine (Correct Answer)
- C. Desflurane
- D. Thiopentone
Explanation: **Ketamine** * **Ketamine** is preferred in shock due to its sympathomimetic properties, which maintain or increase blood pressure and heart rate, thus preserving **cardiovascular stability**. * It also has minimal respiratory depression and bronchodilatory effects, making it safer for patients with compromised respiratory function. * The cardiovascular stimulating effects of ketamine helps maintain haemodynamic stability in shocked patients. It maintains cerebral autoregulation and perfusion of vital organs. *Isoflurane* * **Isoflurane** is an inhaled anesthetic that typically causes **dose-dependent myocardial depression** and **vasodilation**, which can worsen hypotension in a shock state. * It can significantly decrease systemic vascular resistance, thereby exacerbating the already compromised cardiovascular status of a shock patient. *Desflurane* * **Desflurane** is an inhaled anesthetic known for its rapid onset and offset but can cause a **significant increase in heart rate and blood pressure** upon rapid concentration changes, which may be detrimental in an unstable patient. * Like isoflurane, it also causes dose-dependent peripheral vasodilation and myocardial depression, which can worsen hypotension in patients in shock. *Thiopentone* * **Thiopentone** is a barbiturate that causes significant **myocardial depression** and **peripheral vasodilation**, leading to a substantial drop in blood pressure. * Its use in shock would further compromise cardiovascular stability and is generally contraindicated due to its potent hemodynamic depressant effects.
Internal Medicine
1 questionsTuberculin test is positive in general population (immunocompetent individuals with no specific risk factors) if induration is?
NEET-PG 2013 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 1511: Tuberculin test is positive in general population (immunocompetent individuals with no specific risk factors) if induration is?
- A. >7mm
- B. >5mm
- C. >2mm
- D. >10mm (Correct Answer)
Explanation: >10mm - For **immunocompetent** individuals without specific risk factors, a tuberculin skin test (TST) induration of **≥10 mm** is considered positive. - This threshold indicates a likely **exposure to Mycobacterium tuberculosis** and a cellular immune response. *>7mm* - This is not a standard threshold for a positive TST in any risk group. - TST interpretation is based on specific **induration sizes** corresponding to different risk factors. *>5mm* - An induration of **≥5 mm** is considered positive for individuals with compromised immunity, those in close contact with active TB cases, or those with fibrotic changes on chest X-ray. - This lower threshold is used for **high-risk groups** due to their increased susceptibility to developing active tuberculosis. *>2mm* - An induration of **≥2 mm** is not typically used as a positive threshold for the tuberculin test in any established guidelines. - Such a small induration is generally considered **negative** or clinically insignificant.
Ophthalmology
1 questionsSurgery of choice in a patient with congenital ptosis with good levator action is:
NEET-PG 2013 - Ophthalmology NEET-PG Practice Questions and MCQs
Question 1511: Surgery of choice in a patient with congenital ptosis with good levator action is:
- A. Fascia lata sling surgery
- B. Fasanella-Servat operation
- C. Müller's resection
- D. LPS resection (Correct Answer)
Explanation: ***LPS resection*** - **Levator palpebrae superioris (LPS) resection** is the surgery of choice for congenital ptosis with **good levator action** (typically defined as >8-10 mm of levator function). - This procedure directly shortens and strengthens the **levator muscle**, improving eyelid elevation. *Fascia lata sling surgery* - This procedure is indicated for patients with **poor or absent levator function** (typically <4 mm). - It involves suspending the eyelid to the **frontalis muscle** using a sling material, often **fascia lata**, to allow eyebrow elevation to lift the eyelid. *Fasanella-Servat operation* - This is a minimally invasive procedure used for **mild ptosis** with **excellent levator action** (>10 mm). - It involves resecting a small amount of **Müller's muscle**, **conjunctiva**, and occasionally the **tarsal plate**, but is less effective for moderate-to-severe ptosis. *Müller's resection* - **Müller's muscle resection** is generally reserved for **mild ptosis** (1-2 mm) that responds positively to the **phenylephrine test**. - It primarily addresses ptosis due to sympathetic denervation or mild aponeurotic disinsertion, not significant congenital ptosis with good levator function.
Pediatrics
1 questionsAll are used in the treatment of nocturnal enuresis except?
NEET-PG 2013 - Pediatrics NEET-PG Practice Questions and MCQs
Question 1511: All are used in the treatment of nocturnal enuresis except?
- A. Voiding of urine before sleeping (Correct Answer)
- B. Imipramine
- C. Alarm setup
- D. Maintenance of calendar of day night wetting
Explanation: ***Voiding of urine before sleeping*** - **Voiding before sleep** is a **general hygiene measure and preventive advice** rather than a specific therapeutic intervention for nocturnal enuresis. - While it may reduce bladder volume at bedtime, it does **not address the underlying pathophysiology** of nocturnal enuresis (arousal deficit, nocturnal polyuria, or detrusor overactivity). - It is **routine advice** given to all children, not a targeted treatment modality for curing enuresis. *Imipramine* - **Imipramine**, a tricyclic antidepressant, is an established **pharmacological treatment** for nocturnal enuresis. - Its mechanisms include: **anticholinergic effects** (increasing bladder capacity and functional bladder capacity), **alpha-adrenergic effects** (increasing bladder outlet resistance), and **antidiuretic effects**. - Typical dosing: **25-50 mg at bedtime**, with success rates of 40-60%. *Alarm setup* - **Bed-wetting alarms** are the **first-line behavioral therapy** with the highest long-term cure rates (60-70% success). - Works through **classical conditioning**: the alarm triggers when moisture is detected, training the child to either wake to void or develop nocturnal bladder control. - Requires **8-12 weeks** of consistent use and has the lowest relapse rates among treatments. *Maintenance of calendar of day night wetting* - **Voiding diary/calendar** is an essential **behavioral intervention** for monitoring and managing nocturnal enuresis. - Helps identify patterns, track treatment progress, and provides **positive reinforcement** through visual feedback. - Part of comprehensive behavioral management alongside fluid restriction and scheduled voiding during daytime.
Pharmacology
1 questionsWhich is not used in status epilepticus?
NEET-PG 2013 - Pharmacology NEET-PG Practice Questions and MCQs
Question 1511: Which is not used in status epilepticus?
- A. Lorazepam
- B. Phenytoin
- C. Phenobarbitone
- D. Metformin (Correct Answer)
Explanation: ***Metformin*** - **Metformin** is an **oral hypoglycemic agent** used to treat **type 2 diabetes mellitus** and has no role in the management of seizures or status epilepticus. - Its primary mechanism involves decreasing **hepatic glucose production** and improving **insulin sensitivity**. *Lorazepam* - **Lorazepam** is a first-line treatment for **status epilepticus** due to its rapid onset of action and efficacy in terminating seizures. - It enhances the effect of **GABA** (gamma-aminobutyric acid) at the GABA-A receptor, leading to neuronal hyperpolarization and reduced excitability. *Phenytoin* - **Phenytoin** is a common second-line agent used in status epilepticus, administered after benzodiazepines, to maintain seizure control. - It works by blocking **voltage-gated sodium channels**, thereby stabilizing neuronal membranes and preventing repetitive firing. *Phenobarbitone* - **Phenobarbitone** (phenobarbital) is an effective antiepileptic drug, often considered as a second or third-line agent in status epilepticus, especially when other treatments fail. - It acts primarily by enhancing the activity of **GABA** at the GABA-A receptor, similar to benzodiazepines, but with a longer duration of action.
Physiology
2 questionsHormone primarily responsible for blood pressure regulation following acute blood loss is:
Which of the following actions of GH is mediated by IGF-1?
NEET-PG 2013 - Physiology NEET-PG Practice Questions and MCQs
Question 1511: Hormone primarily responsible for blood pressure regulation following acute blood loss is:
- A. Aldosterone
- B. ANP
- C. Epinephrine
- D. ADH (Correct Answer)
Explanation: ***ADH*** - **Antidiuretic hormone (ADH)**, also known as **vasopressin**, is released in response to decreased blood volume and pressure detected by **baroreceptors**. - Its primary role is to increase water reabsorption in the **renal collecting ducts** and cause **vasoconstriction**, both of which help restore blood volume and pressure. - This makes ADH the key **hormonal mechanism** for BP regulation following acute blood loss. *Aldosterone* - **Aldosterone** is crucial for long-term **blood pressure regulation** by increasing sodium and water reabsorption in the kidneys. - While important for volume restoration, its effects are **slower** (hours) and more focused on electrolyte balance rather than immediate BP stabilization after acute blood loss. *ANP* - **Atrial natriuretic peptide (ANP)** is released in response to **atrial stretch** due to increased blood volume and acts to lower blood pressure. - It promotes **vasodilation** and **sodium/water excretion**, counteracting the body's efforts to raise blood pressure after blood loss. - ANP levels are **suppressed** during hypovolemia. *Epinephrine* - **Epinephrine** increases heart rate and cardiac contractility, and causes vasoconstriction, providing an immediate increase in blood pressure. - However, it's primarily a **catecholamine** (not a classic hormone) part of the **sympathetic nervous system** response, and while it acts immediately, ADH provides the sustained hormonal BP regulation.
Question 1512: Which of the following actions of GH is mediated by IGF-1?
- A. Na+ retention
- B. decreases insulin
- C. Antilipolysis (Correct Answer)
- D. Lipolysis
Explanation: ***Antilipolysis*** * **Insulin-like growth factor 1 (IGF-1)**, stimulated by GH, plays a role in reducing **lipolysis** indirectly. * IGF-1 promotes **anabolic processes** and nutrient storage, which can lead to decreased fat breakdown. *Na+ retention* * **Na+ retention** is more directly influenced by hormones like **aldosterone** and **ADH**, not IGF-1. * While GH can exert some influence on fluid and electrolyte balance, this specific action is not primarily mediated by IGF-1. *decreases insulin* * IGF-1 and GH generally tend to **increase insulin sensitivity** in some tissues or antagonize insulin effects indirectly. * IGF-1's primary metabolic role is not to decrease insulin itself directly. *Lipolysis* * **Growth hormone (GH)** directly promotes **lipolysis**, breaking down fat for energy. * However, the question specifically asks for actions mediated by **IGF-1**, which has an opposite, antilipolytic effect.
Surgery
3 questionsFatal exsanguination occurs most commonly in
Tensile strength of a wound becomes normal after:
Sistrunk operation is for:
NEET-PG 2013 - Surgery NEET-PG Practice Questions and MCQs
Question 1511: Fatal exsanguination occurs most commonly in
- A. Closed fracture of the femoral shaft
- B. Partial transection of an artery (Correct Answer)
- C. Complete transection of an artery
- D. Open fracture of the femur and tibia
Explanation: ***Partial transection of an artery*** - A **partially transected artery** is the most dangerous scenario for fatal exsanguination - The vessel walls **cannot retract or undergo effective vasospasm** because they remain tethered - The torn opening remains patent, allowing **continuous and profuse bleeding** - This is a classic surgical principle: **partial arterial injuries bleed more than complete transections** - Without prompt surgical control, this leads to rapid and fatal exsanguination *Complete transection of an artery* - When an artery is completely transected, the vessel ends **retract and go into spasm** - This natural hemostatic mechanism significantly **reduces immediate blood loss** - While still serious and requiring urgent treatment, complete transection is **less likely to cause fatal exsanguination** than partial transection - The retraction and spasm provide temporary hemostasis until definitive repair *Open fracture of the femur and tibia* - Can cause significant bleeding from muscle, soft tissue, and bone - However, the bleeding is typically **not from major arterial injury** unless vessels are directly damaged - Usually controllable with **tourniquets, pressure dressings, and splinting** - Less likely to cause immediate fatal exsanguination compared to major arterial injury *Closed fracture of the femoral shaft* - Can result in substantial internal blood loss (up to **1-1.5 liters** into the thigh compartment) - May cause **hypovolemic shock** requiring transfusion - However, the closed space provides some tamponade effect - Rarely causes immediate **fatal exsanguination** unless associated with other major injuries
Question 1512: Tensile strength of a wound becomes normal after:
- A. Never (Correct Answer)
- B. 6 months
- C. 4 months
- D. 6 weeks
Explanation: ***Never*** - A healed wound, even after complete maturation, only achieves about **80% of the original tissue's tensile strength** - The process of scar formation involves the realignment of collagen fibers and increased cross-linking, but it can **never perfectly replicate** the pre-injury tissue architecture and strength - This is a fundamental principle of wound healing - scar tissue is structurally different from normal tissue *6 months* - By 6 months, a wound's tensile strength has typically reached its **maximum potential** of approximately 80%, but this is still less than 100% of the original tissue's strength - This period marks the end of the significant remodeling phase, where collagen fibers are reorganized and strengthened *4 months* - At 4 months, the wound is still undergoing substantial **remodeling and strengthening**, achieving approximately 70-80% of eventual tensile strength - While considerable strength is gained by this time, further improvements continue for several more months *6 weeks* - At 6 weeks, the wound has achieved about **50-70% of its eventual tensile strength** - This stage is characterized by increased collagen deposition and cross-linking, making the wound clinically strong, but it is far from its maximum or normal strength
Question 1513: Sistrunk operation is for:
- A. Thyroglossal fistula
- B. Branchial fistula
- C. Thyroglossal cyst (Correct Answer)
- D. Branchial cyst
Explanation: ***Thyroglossal cyst*** - The **Sistrunk operation** is the definitive surgical procedure for the removal of a **thyroglossal duct cyst**. - This procedure involves excising the cyst along with the central portion of the **hyoid bone** and a core of muscle from the posterior aspect of the hyoid to the foramen cecum to prevent recurrence. *Thyroglossal fistula* - A **thyroglossal fistula** is a complication of a thyroglossal cyst that has ruptured or been surgically incised, leading to a persistent tract to the skin. - While a Sistrunk operation may be performed for a fistula, it is primarily indicated for the *cyst* itself to prevent both recurrence of the cyst and subsequent fistula formation. *Branchial fistula* - A **branchial fistula** is a congenital anomaly resulting from incomplete closure of the branchial arches during embryonic development, leading to an abnormal tract between the neck and the pharynx or skin. - Surgical excision of a branchial fistula is a different procedure from the Sistrunk operation, as its anatomical location and developmental origin are distinct from those of a thyroglossal cyst. *Branchial cyst* - A **branchial cyst** is a congenital neck mass arising from remnants of the branchial arches, typically presenting as a painless, soft, movable lump in the lateral neck. - While also a congenital neck cyst requiring surgical excision, the surgical approach for a branchial cyst does not involve the hyoid bone in the same manner as the Sistrunk operation due to its different embryological origin and location.