NEET-PG 2012 Practice Questions

Q: In which context can helium replace nitrogen as a diluent gas in oxygen mixtures?

None of the options. **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.

Q: Which of the following cannot be given by epidural anaesthesia?

Remifentanil. ***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**.

Q: In a severely anaemic pregnant patient presenting with cardiac failure, what is the most appropriate choice of transfusion?

Exchange transfusion. ***Exchange transfusion*** - In **severe anaemia with cardiac failure**, exchange transfusion simultaneously **removes** and **replaces** blood volume, correcting anaemia without **net volume increase** that could worsen cardiac failure. - This procedure is the **safest option** as it avoids **fluid overload** while effectively improving **oxygen-carrying capacity** in cardiac-compromised pregnant patients. *Platelets* - **Platelets** are indicated for **thrombocytopenia** or **platelet dysfunction** to prevent bleeding, not for correcting anaemia. - They provide no benefit for **oxygen transport** or the underlying cause of cardiac failure in this anaemic patient. *Packed cells* - **Packed red blood cells** still add **net volume** to circulation, which can precipitate **pulmonary edema** and worsen cardiac failure despite slower infusion. - Even with **diuretics**, the risk of **fluid overload** remains significant in patients with pre-existing cardiac compromise. *Whole blood* - **Whole blood** contains **plasma volume** that significantly increases circulatory load, making it particularly dangerous in cardiac failure. - The large **volume expansion** can rapidly lead to **congestive heart failure** and **pulmonary edema** in already compromised patients.

Q: What is the most common cause of hydrops fetalis in current medical practice?

Cardiac malformations. ***Cardiac malformations*** - **Cardiovascular abnormalities** are the **most common cause** of **non-immune hydrops fetalis** in current medical practice, accounting for **20-40%** of cases - Includes **structural heart defects** (septal defects, valvular abnormalities) and **arrhythmias** (supraventricular tachycardia, complete heart block) - These conditions lead to **heart failure** and **increased hydrostatic pressure**, causing fluid accumulation in fetal tissues and body cavities - With the near-elimination of Rh disease through immunoprophylaxis, cardiac causes have emerged as the leading etiology *Chromosomal abnormalities* - Account for **10-20%** of non-immune hydrops cases - **Turner syndrome (45,X)** is the most common chromosomal cause, associated with **cystic hygroma** and **lymphatic dysgenesis** - Other chromosomal conditions include **trisomy 21, 18, and 13**, which can cause hydrops through associated cardiac defects or other mechanisms - While significant, chromosomal causes are less common than cardiovascular causes overall *Fetal infections (e.g., parvovirus B19)* - Infections account for **5-10%** of non-immune hydrops cases - **Parvovirus B19** is the most common infectious cause, leading to severe **fetal anemia** through bone marrow suppression - Other infectious agents include **CMV**, **toxoplasmosis**, and **syphilis** - The TORCH screening helps identify treatable infectious causes *Rh incompatibility (historically significant)* - Historically the **leading cause** before the 1970s, accounting for most hydrops cases - Now accounts for **<10%** of cases due to routine **Rho(D) immune globulin (RhoGAM)** administration at 28 weeks and postpartum - Causes **immune hydrops** through maternal antibodies crossing the placenta and destroying fetal red blood cells, leading to severe anemia and heart failure - Still important in under-immunized populations or cases of missed prophylaxis

Q: Which of the following statements about tuberculosis (TB) of the uterus is NOT true?

Most common is ascending infection. ***Most common is ascending infection*** - Uterine tuberculosis is overwhelmingly due to **hematogenous spread** from a primary site, often the lungs, rather than an ascending infection from the lower genital tract. - Tuberculosis typically reaches the female genital tract by the **bloodstream**, with the fallopian tubes being the most common initial site of involvement. *Mostly secondary* - Genital tuberculosis, including uterine involvement, is almost always a **secondary infection**, meaning it results from the spread of Mycobacterium tuberculosis from another primary site in the body, most commonly the lungs. - The initial infection establishes elsewhere, and then the bacteria **disseminate hematogenously** to the reproductive organs. *Increase incidence of ectopic pregnancy* - Tubal damage and scarring caused by tuberculosis, particularly in the fallopian tubes (**salpingitis**), disrupt the normal passage of the ovum. - This anatomical alteration significantly **increases the risk** of the fertilized egg implanting outside the uterus, leading to ectopic pregnancy. *Involvement of endosalpinx* - The **fallopian tubes (endosalpinx)** are the most common site of genital tuberculosis, with eventual spread to the uterus through the lymphatic system or direct extension. - Tubal involvement can lead to **salpingitis isthmica nodosa** and hydrosalpinx, contributing to infertility and ectopic pregnancy.

Q: What is the primary use of prophylactic methergin?

To stop excess bleeding from uterus. ***To stop excess bleeding from uterus*** - **Methergin (Methylergonovine)** is an **ergot alkaloid** that causes strong contractions of the **uterus**. - Its primary prophylactic use is to **prevent or treat postpartum hemorrhage** by contracting the uterus and compressing blood vessels. *Induction of labour* - **Methergin** is generally **contraindicated for labor induction** as its potent, sustained contractions can cause **hypertonic uterine dysfunction** and fetal distress. - **Oxytocin** is the preferred agent for **labor induction** due to its more physiological contraction pattern. *Induction of abortion* - While methergin can cause uterine contractions, it is **not the primary agent for abortion induction**. - **Prostaglandins (e.g., misoprostol)** and other pharmacological agents are typically used in combination for **medical abortion**. *None of the options* - This option is incorrect because **stopping excess uterine bleeding** is indeed a primary use of prophylactic methergin, particularly in the postpartum period. - The other options describe situations where methergin is either not indicated or is a secondary/contraindicated choice.

Q: What is a definitive indication for performing a Lower Segment Cesarean Section (LSCS)?

Contracted pelvis. ***Contracted pelvis*** - A **contracted pelvis** means the maternal pelvic dimensions are too small to allow for the safe passage of the fetus, making a vaginal birth impossible or highly risky. - This **fetopelvic disproportion** (cephalopelvic disproportion) necessitates a C-section to prevent obstructed labor, fetal distress, and potential harm to both mother and baby. - A contracted pelvis is a **definitive indication** for LSCS as vaginal delivery is contraindicated. *Mento anterior presentation* - In a **mento anterior presentation**, the fetal chin (mentum) is anterior, which is a **favorable position** for vaginal delivery as it allows for proper neck extension and engagement. - This presentation does not typically require a C-section unless there are other complicating factors. *Occipito posterior presentation* - While an **occipito posterior presentation** can sometimes lead to prolonged labor or the need for instrumental delivery, it is **not an absolute indication** for C-section. - Many cases can still deliver vaginally, either spontaneously or with rotation, and surgical intervention is usually reserved for failure to progress or fetal distress. *Vertex presentation* - A **vertex presentation** means the fetal head is flexed and presenting first, which is the **most common and ideal presentation** for a vaginal birth. - This presentation is a sign of a normal, potentially uncomplicated delivery and is the opposite of an indication for C-section.

Q: All are causes of anovulatory amenorrhea except which of the following?

Gonadal dysgenesis. ***Gonadal dysgenesis*** - This condition is a cause of **primary ovarian insufficiency**, leading to amenorrhea but not primarily due to anovulation in a previously cycling individual. - In gonadal dysgenesis, the **ovaries are malformed or absent**, resulting in a lack of follicles and thus no ovulation or estrogen production from the start. *PCOD* - **Polycystic Ovarian Disease** (PCOD/PCOS) is a common cause of anovulatory amenorrhea, characterized by **oligo- or anovulation**, clinical or biochemical hyperandrogenism, and polycystic ovaries on ultrasound. - The hormonal imbalance (e.g., elevated **androgens**, high **LH/FSH ratio**) disrupts normal follicular development and ovulation. *Hyperprolactinemia* - **Elevated prolactin levels** inhibit the pulsatile secretion of **GnRH (Gonadotropin-Releasing Hormone)** from the hypothalamus, which in turn reduces FSH and LH release from the pituitary. - This suppression of gonadotropins leads to impaired follicular development and **anovulation**, resulting in amenorrhea. *Drugs* - Various medications can cause anovulatory amenorrhea by interfering with the **hypothalamic-pituitary-ovarian axis**. - Examples include antipsychotics (which can increase **prolactin levels**), certain antidepressants, opioids, and chemotherapy agents that can damage ovarian function.

Q: Osteonecrosis is seen in all except

Paget's disease. ***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.

Q: Drug of choice for Pneumocystis jirovecii in pregnancy?

Trimethoprim-sulfamethoxazole (SMZ/TMP). ***Trimethoprim-sulfamethoxazole (SMZ/TMP)*** - Despite being a **folate antagonist**, SMZ/TMP is considered safe and the **drug of choice** for treating **Pneumocystis jirovecii pneumonia (PJP)** in pregnant women, particularly as the benefits outweigh the risks. - It is recommended to supplement with **folic acid** during treatment to mitigate potential teratogenic risks, although these risks are generally low. *Primaquine* - **Primaquine** is primarily used for the treatment of **Plasmodium vivax** and **Plasmodium ovale malaria**, specifically targeting hypnozoites in the liver. - It is contraindicated in pregnancy due to the risk of **hemolytic anemia** in the fetus, especially if the fetus has **glucose-6-phosphate dehydrogenase (G6PD) deficiency**. *Dapsone* - **Dapsone** is used in the treatment of **leprosy**, **dermatitis herpetiformis**, and as an alternative for **PJP prophylaxis** in HIV-positive patients. - While it can be used for PJP prophylaxis, its efficacy for **active PJP treatment** is lower than SMZ/TMP, and it carries risks of **hemolytic anemia** and **methemoglobinemia**, particularly in pregnancy. *Pentamidine* - **Pentamidine** is an alternative treatment for **PJP**, especially in patients who cannot tolerate SMZ/TMP. - It is typically reserved for **severe cases** or as a second-line agent due to its potential for **significant toxicity**, including hypotension, nephrotoxicity, and hypoglycemia, which can be particularly concerning in pregnancy.

Question 1

In which context can helium replace nitrogen as a diluent gas in oxygen mixtures?

Accepted Answer

None of the options

Answer

Argon

Answer

Xenon

Answer

Helium

Question 2

Which of the following cannot be given by epidural anaesthesia?

Accepted Answer

Remifentanil

Answer

Morphine

Answer

Alfentanil

Answer

Fentanyl

Question 3

In a severely anaemic pregnant patient presenting with cardiac failure, what is the most appropriate choice of transfusion?

Accepted Answer

Exchange transfusion

Answer

Platelets

Answer

Packed cells

Answer

Whole blood

Question 4

What is the most common cause of hydrops fetalis in current medical practice?

Accepted Answer

Cardiac malformations

Answer

Fetal infections (e.g., parvovirus B19)

Answer

Chromosomal abnormalities

Answer

Rh incompatibility (historically significant)

Question 5

Which of the following statements about tuberculosis (TB) of the uterus is NOT true?

Accepted Answer

Most common is ascending infection

Answer

Increase incidence of ectopic pregnancy

Answer

Involvement of endosalpinx

Answer

Mostly secondary

Question 6

What is the primary use of prophylactic methergin?

Accepted Answer

To stop excess bleeding from uterus

Answer

None of the options

Answer

Induction of labour

Answer

Induction of abortion

Question 7

What is a definitive indication for performing a Lower Segment Cesarean Section (LSCS)?

Accepted Answer

Contracted pelvis

Answer

Mento anterior presentation

Answer

Occipito posterior presentation

Answer

Vertex presentation

Question 8

All are causes of anovulatory amenorrhea except which of the following?

Accepted Answer

Gonadal dysgenesis

Answer

Hyperprolactinemia

Answer

Drugs

Answer

PCOD

Question 9

Osteonecrosis is seen in all except

Accepted Answer

Paget's disease

Answer

Fracture neck femur

Answer

Perthe's disease

Answer

Sickle cell anemia

Question 10

Drug of choice for Pneumocystis jirovecii in pregnancy?

Accepted Answer

Trimethoprim-sulfamethoxazole (SMZ/TMP)

Answer

Primaquine

Answer

Dapsone

Answer

Pentamidine

NEET-PG 2012

Anesthesiology

Obstetrics and Gynecology

Orthopaedics

Pharmacology