Anesthesiology
3 questionsWhat is the most reliable indicator to prevent esophageal intubation?
In which context can helium replace nitrogen as a diluent gas in oxygen mixtures?
Which of the following cannot be given by epidural anaesthesia?
NEET-PG 2012 - Anesthesiology NEET-PG Practice Questions and MCQs
Question 1141: What is the most reliable indicator to prevent esophageal intubation?
- A. Oxygen saturation on pulse oximeter
- B. Direct visualization of passing tube beneath vocal cords
- C. Auscultation over chest
- D. Measurement of CO2 in exhaled air (EtCO2). (Correct Answer)
Explanation: ***Measurement of CO2 in exhaled air (EtCO2)*** - The presence of **carbon dioxide** in exhaled air confirms tracheal intubation as the esophagus does not contain CO2. - This method provides a **real-time**, objective assessment of tube placement that is highly reliable because even small amounts of CO2 are detected. *Oxygen saturation on pulse oximeter* - This indicator measures **oxygenation**, which can remain adequate for several minutes after esophageal intubation due to pre-oxygenation. - A **delayed drop in saturation** might indicate esophageal intubation, but it's not immediate and therefore not the most reliable early indicator. *Direct visualization of passing tube beneath vocal cords* - While helpful, **direct visualization** can sometimes be misleading due to difficult airways or poor visibility, where the tube might appear to pass correctly but enter the esophagus. - This method is **operator-dependent** and its reliability can vary based on the intubator's experience and the patient's anatomy. *Auscultation over chest* - **Auscultation** can detect breath sounds; however, sounds can be transmitted from the stomach or surrounding tissues, leading to false positives. - It is also very difficult to reliably distinguish between **esophageal and tracheal sounds**, especially in noisy environments or with inexperienced personnel, making it less reliable than EtCO2.
Question 1142: In which context can helium replace nitrogen as a diluent gas in oxygen mixtures?
- A. Argon
- B. Xenon
- C. Helium
- D. None of the options (Correct Answer)
Explanation: **None of the options** - This question implies that helium might replace *another noble gas* as a diluent, but the correct application is for helium to replace **nitrogen** in oxygen mixtures, particularly in **diving applications**. This question likely has a flaw in its premise if expecting one of the noble gases listed to be the 'replacement' for nitrogen, as helium *is* the replacement. - Helium is used instead of nitrogen in diving gases (**trimix, heliox**) for deep dives because it is less narcotic than nitrogen under pressure, reducing the risk of **nitrogen narcosis**. *Argon* - **Argon** is denser than nitrogen and has a higher narcotic potential at depth, making it unsuitable as a replacement for nitrogen in diving gases. - It is sometimes used during **dry suit inflation** for insulation due to its low thermal conductivity, but not as a breathing gas diluent. *Xenon* - **Xenon** is a potent anesthetic agent, even at atmospheric pressure, due to its high lipid solubility. - Its use as a diluent would cause severe **narcosis** and render a diver unconscious, making it entirely inappropriate for diving mixtures. *Helium* - While helium is indeed the gas that replaces nitrogen as a diluent in oxygen mixtures for deep diving, it being listed as an option here suggests a misunderstanding of the question's phrasing. The question is asking for **in which context** helium can replace nitrogen, not asking to identify helium itself as the replacement. - Given the other options are noble gases that *cannot* replace nitrogen in this context, "None of the options" is the most accurate answer if the question implies picking from the provided list for a replacement *for helium* or a suitable *alternative* to helium, which isn't the case here.
Question 1143: Which of the following cannot be given by epidural anaesthesia?
- A. Morphine
- B. Remifentanil (Correct Answer)
- C. Alfentanil
- D. Fentanyl
Explanation: ***Remifentanil*** - **Remifentanil** is specifically designed for **intravenous administration** and is rapidly metabolized by plasma esterases, making it unsuitable for epidural use. - Due to its short half-life and rapid metabolism, epidural administration would provide inconsistent and fleeting analgesia, and its breakdown products are not inert in the epidural space, potentially causing **neurotoxicity**. *Morphine* - **Morphine** is a commonly used opioid for **epidural analgesia** due to its hydrophilicity, allowing for prolonged action in the cerebrospinal fluid. - It provides effective **postoperative pain relief** and has a relatively slow onset but long duration of action when administered epidurally. *Alfentanil* - **Alfentanil** is a synthetic opioid that has been used for **epidural analgesia**, though less commonly than fentanyl or sufentanil, sometimes in conjunction with local anesthetics. - It has a faster onset and shorter duration of action compared to morphine, but still provides effective **analgesia** when administered epidurally. *Fentanyl* - **Fentanyl** is a widely used lipophilic opioid for **epidural analgesia**, often combined with local anesthetics, for both surgical and obstetric pain. - Its lipophilicity allows for rapid absorption and a relatively quick onset of action, providing effective **segmental analgesia**.
Dermatology
1 questionsPhrynoderma is primarily associated with a deficiency of which of the following?
NEET-PG 2012 - Dermatology NEET-PG Practice Questions and MCQs
Question 1141: Phrynoderma is primarily associated with a deficiency of which of the following?
- A. Essential fatty acid
- B. Vitamin A (Correct Answer)
- C. Vitamin D
- D. Niacin
Explanation: ***Vitamin A*** - **Phrynoderma** (toad skin) has been **classically attributed to vitamin A deficiency** in traditional medical literature and was the accepted answer in historical examinations. - It presents as **follicular hyperkeratosis** with dry, scaly, rough skin having prominent hair follicles with a sandpaper-like texture. - However, **modern evidence** suggests phrynoderma is a **multifactorial condition** often involving **multiple nutritional deficiencies**, with vitamin A being one important contributor among others. *Essential fatty acid* - Deficiency of **essential fatty acids** (linoleic and alpha-linolenic acid) causes **skin dryness, flakiness, and follicular hyperkeratosis**. - **Recent studies** indicate EFA deficiency may play a **significant role** in phrynoderma, particularly in developing countries where multiple nutritional deficiencies coexist. - The clinical presentation can closely mimic vitamin A deficiency-related skin changes. *Vitamin D* - Deficiency of **vitamin D** primarily causes **rickets** in children and **osteomalacia** in adults with bone pain, muscle weakness, and skeletal deformities. - While vitamin D has roles in skin health, its deficiency does not directly cause the follicular hyperkeratosis characteristic of phrynoderma. *Niacin* - **Niacin (vitamin B3)** deficiency causes **pellagra** with the classic \"3 Ds\": **dermatitis, diarrhea, and dementia**. - Pellagra dermatitis is typically **symmetrical in sun-exposed areas** with redness, scaling, and hyperpigmentation—distinctly different from the follicular pattern of phrynoderma.
Internal Medicine
2 questionsHereditary angioneurotic edema is due to?
In a severely anaemic pregnant patient presenting with cardiac failure, what is the most appropriate choice of transfusion?
NEET-PG 2012 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 1141: Hereditary angioneurotic edema is due to?
- A. Deficiency of C1 inhibitor (Correct Answer)
- B. Deficiency of NADPH oxidase
- C. Deficiency of MPO
- D. Deficiency of properdin
Explanation: ***Deficiency of C1 inhibitor*** - **Hereditary angioedema (HAE)** is caused by a genetic deficiency or dysfunction of the **C1 esterase inhibitor (C1-INH)** protein. - C1-INH normally regulates the **complement system**, kinin system (mediating **bradykinin** release), and coagulation pathways, and its deficiency leads to uncontrolled activation and excessive bradykinin production, causing angioedema. *Deficiency of NADPH oxidase* - A deficiency in **NADPH oxidase** is associated with **Chronic Granulomatous Disease (CGD)**, a primary immunodeficiency characterized by recurrent bacterial and fungal infections due to impaired phagocytic oxidative burst. - It does not cause angioedema, which involves fluid extravasation rather than impaired microbial killing. *Deficiency of MPO* - **Myeloperoxidase (MPO) deficiency** typically leads to mild to moderate impairment in the killing of certain microorganisms by phagocytes but is often asymptomatic or causes only recurrent candidal infections. - It is not linked to the pathogenesis of angioedema, which involves dysregulation of vasoactive peptides. *Deficiency of properdin* - A deficiency in **properdin** affects the **alternative pathway of the complement system**, increasing susceptibility to **Neisseria infections**. - While properdin is part of the complement system, its deficiency does not directly lead to the uncontrolled production of bradykinin, which is the primary mediator in angioedema due to C1-INH deficiency.
Question 1142: In a severely anaemic pregnant patient presenting with cardiac failure, what is the most appropriate choice of transfusion?
- A. Platelets
- B. Packed cells (Correct Answer)
- C. Whole blood
- D. Exchange transfusion
Explanation: ***Packed cells*** - **Packed red blood cells (PRBCs)** increase **oxygen-carrying capacity** with minimal volume expansion, which is crucial in patients with cardiac compromise [1]. - Slow infusion of PRBCs, often with a **diuretic**, can improve anaemia and cardiac function while preventing **fluid overload**. *Platelets* - **Platelets** are primarily transfused for **thrombocytopenia** or **platelet dysfunction** to prevent or treat bleeding. - They do not address the low haemoglobin and oxygen-carrying deficit directly contributing to cardiac failure in an anaemic patient. *Whole blood* - **Whole blood** contains plasma, which can significantly increase circulatory volume and worsen **cardiac failure** in patients already struggling with fluid balance. - While it does provide red cells, the added volume makes it a less safe option compared to packed cells in this scenario. *Exchange transfusion* - An **exchange transfusion** involves removing a patient's blood and replacing it with donor blood, typically used for severe conditions like **sickle cell crisis** or **severe hyperbilirubinemia** [2]. - This procedure is complex and carries higher risks, and is not the first-line treatment for anaemia-induced cardiac failure in pregnancy.
Orthopaedics
3 questionsOsteonecrosis is seen in all except
In elbow, osteochondritis usually involves
What is the primary use of a knuckle bender splint?
NEET-PG 2012 - Orthopaedics NEET-PG Practice Questions and MCQs
Question 1141: Osteonecrosis is seen in all except
- A. Fracture neck femur
- B. Paget's disease (Correct Answer)
- C. Perthe's disease
- D. Sickle cell anemia
Explanation: ***Paget's disease*** - **Paget's disease of bone (osteitis deformans)** is a localized disorder of bone remodeling, characterized by excessive and disorganized bone formation, leading to enlarged, softened, and misshapen bones, but not directly causing osteonecrosis. - While complications like **pathological fractures** and **osteosarcoma** can occur, primary osteonecrosis is not a typical feature of Paget's disease itself. *Fracture neck femur* - **Fractures of the femoral neck** can disrupt the blood supply to the femoral head, particularly the medial circumflex femoral artery, leading to **avascular necrosis** (osteonecrosis) of the femoral head. - This is a well-known and common complication, especially in displaced fractures. *Sickle cell anemia* - **Sickle cell anemia** causes sickling of red blood cells, leading to **vaso-occlusion** and impaired blood flow to bones, resulting in **bone infarcts** (osteonecrosis). - This can affect various bones, including the femoral head, humeral head, and vertebrae. *Perthe's disease* - **Perthe's disease** (Legg-Calvé-Perthes disease) is a childhood condition characterized by **idiopathic osteonecrosis** of the femoral head. - It involves the collapse and subsequent re-ossification of the femoral epiphysis due to an interruption of its blood supply.
Question 1142: In elbow, osteochondritis usually involves
- A. Olecranon
- B. Trochlea
- C. Radial head
- D. Capitulum (Correct Answer)
Explanation: ***Capitulum*** - The **capitulum** of the humerus is the most common site for **osteochondritis dissecans (OCD)** in the elbow, especially in throwing athletes and gymnasts. - This condition involves an avascular necrosis of the subchondral bone leading to a detachment of a cartilage fragment. *Olecranon* - The **olecranon** is part of the ulna and is more commonly affected by **stress fractures** or **bursitis**, not typically osteochondritis. - While it articulates with the trochlea, it does not bear the primary compressive forces that lead to osteochondritis in the same way the capitulum does. *Trochlea* - The **trochlea** of the humerus articulates with the trochlear notch of the ulna and is less frequently involved in primary osteochondritis compared to the capitulum. - Pathologies here are more likely related to **instability** or **fractures**. *Radial head* - The **radial head** articulates with the capitulum and is more prone to **fractures** or degenerative changes like **osteoarthritis**. - While it can be affected by **osteochondral lesions**, the capitulum is the classic site for elbow osteochondritis dissecans.
Question 1143: What is the primary use of a knuckle bender splint?
- A. Ulnar nerve palsy (Correct Answer)
- B. Radial nerve palsy
- C. Median nerve palsy
- D. Axillary nerve palsy
Explanation: ***Ulnar nerve palsy*** - A knuckle bender splint is primarily used to counteract the characteristic **claw hand deformity** seen in ulnar nerve palsy [1] by maintaining the **metacarpophalangeal (MCP) joints** in flexion. - This splint helps improve function by preventing hyperextension of the MCP joints, which commonly occurs due to the unopposed action of the extensor muscles when the ulnar nerve is compromised. *Radial nerve palsy* - Radial nerve palsy typically results in **wrist drop** and an inability to extend the wrist and fingers, which is managed with wrist extension splints, not knuckle benders. - The primary goal of splinting in radial nerve palsy is to support the wrist in extension to facilitate grasping and carrying objects. *Median nerve palsy* - Median nerve palsy causes problems with thumb opposition and sensation in the first three and a half digits, often leading to an **ape hand deformity**. - Splints for median nerve palsy focus on maintaining the thumb in opposition, such as a **thumb spica splint**, which differs from a knuckle bender. *Axillary nerve palsy* - Axillary nerve palsy primarily affects the **deltoid muscle**, leading to weakness in shoulder abduction and external rotation. - Splinting for axillary nerve palsy typically involves shoulder immobilizers or abduction splints, which address shoulder joint positioning rather than hand function.
Physiology
1 questionsWhich hormone surge indicates the fertile period in females?
NEET-PG 2012 - Physiology NEET-PG Practice Questions and MCQs
Question 1141: Which hormone surge indicates the fertile period in females?
- A. LH (Correct Answer)
- B. FSH
- C. Estrogen
- D. Oxytocin
Explanation: ***LH*** - The **luteinizing hormone (LH) surge** triggers **ovulation**, releasing a mature egg from the follicle. - This surge is a key indicator of the **fertile window** in a woman's menstrual cycle. *FSH* - **Follicle-stimulating hormone (FSH)** primarily stimulates the growth and development of **ovarian follicles** early in the menstrual cycle, prior to the fertile period. - While essential for follicle maturation, it does not directly signal the immediate fertile window or ovulation. *Estrogen* - **Estrogen levels peak** just before the LH surge, playing a role in triggering the surge itself through positive feedback. - However, estrogen itself does not directly indicate the onset of the fertile period; rather, the subsequent LH surge does. *Oxytocin* - **Oxytocin** is largely involved in processes like **uterine contractions during childbirth** and **milk ejection during lactation**. - It has no direct role in indicating a female's fertile period or timing of ovulation.