FMGE 2018 Practice Questions

Q: Which of the following is the most suitable anesthetic agent for use in dogs?

Propofol. ***Propofol*** - **Propofol** is a widely used and highly effective intravenous anesthetic in dogs due to its **rapid induction** and **rapid recovery**. - It produces minimal cumulative effects when administered as a constant rate infusion, making it suitable for both short procedures and maintenance of anesthesia. *Medetomidine hydrochloride* - **Medetomidine** is an **alpha-2 agonist** primarily used as a sedative and analgesic in dogs, not typically as the sole anesthetic agent for general anesthesia. - While it provides profound sedation, it is usually combined with other drugs (e.g., ketamine) to achieve surgical planes of anesthesia, and its effects on reducing heart rate and blood pressure can be significant. *Ketamine* - **Ketamine** is a **dissociative anesthetic** that provides good analgesia and somatic anesthesia but often causes muscle rigidity and can increase sympathetic tone. - It is typically used in combination with other sedatives or tranquilizers (e.g., diazepam, midazolam) to ensure smooth induction and recovery and prevent adverse effects like seizures. *Midazolam* - **Midazolam** is a **benzodiazepine** primarily used as a sedative, anxiolytic, and muscle relaxant, often as a premedicant or co-induction agent, not as a primary anesthetic for general anesthesia in dogs. - It offers minimal cardiovascular and respiratory depression when used alone, but it does not produce sufficient anesthetic depth for surgical procedures.

Q: Km increases, but Vmax remains same. This is which type of inhibition?

Competitive. ***Competitive*** - In **competitive inhibition**, the inhibitor **reversibly binds** to the **active site** of the enzyme, competing with the substrate. - This competition means that a higher substrate concentration is required to achieve half-maximal velocity, thus **increasing the Km**, while the maximum velocity (**Vmax**) remains unchanged if sufficient substrate is present. *Uncompetitive* - **Uncompetitive inhibition** involves the inhibitor binding only to the **enzyme-substrate complex**. - This type of inhibition typically leads to a **decrease in both Km and Vmax**. *Non-competitive* - In **non-competitive inhibition**, the inhibitor binds to a site other than the active site (allosteric site) on either the free enzyme or the enzyme-substrate complex. - This binding usually **decreases the Vmax** (due to reduced enzyme efficiency) but does not affect the Km (as substrate binding is not directly hindered). *Irreversible* - **Irreversible inhibition** involves the formation of a strong, often covalent, bond between the inhibitor and the enzyme, permanently inactivating it. - This type of inhibition effectively **reduces the concentration of active enzyme**, leading to a **decrease in Vmax** (as fewer enzyme molecules are available to catalyze the reaction) with varying effects on Km depending on the mechanism.

Q: On ECG, ST segment elevation is seen in all of the following conditions EXCEPT:

Hypocalcemia. ***Hypocalcemia*** - While hypocalcemia affects cardiac electrical activity by prolonging the **QT interval**, it is not typically associated with **ST segment elevation**. [3] - The primary ECG finding in hypocalcemia is a **prolonged ST segment**, which then leads to a prolonged QT interval, not an elevated ST segment. *Acute pericarditis* - Characteristically presents with **diffuse concave ST segment elevation** in many leads, often accompanied by **PR segment depression**. - This is due to inflammation of the pericardium affecting the epicardial layer of the myocardium. *Myocardial infarction* - **ST segment elevation** is a hallmark of an acute **ST-segment elevation myocardial infarction (STEMI)**, indicating transmural ischemia. [1], [2] - The location of ST elevation corresponds to the affected coronary artery and myocardial territory. [4] *Left ventricular aneurysm* - Can cause **persistent ST segment elevation** in the leads corresponding to the aneurysm, even after the acute phase of a myocardial infarction. - This persistent elevation is thought to be due to **dyskinetic or akinetic wall motion** and altered repolarization in the scarred tissue.

Q: Beta-hCG is secreted by:

Syncytiotrophoblast. ***Syncytiotrophoblast*** - The **syncytiotrophoblast** is the outer layer of the trophoblast that surrounds the blastocyst and later the chorionic villi. - It is responsible for the secretion of various hormones, including **beta-hCG**, which is crucial for maintaining the corpus luteum and pregnancy. *Yolk sac* - The **yolk sac** is involved in early nutrient transfer, hematopoiesis, and germ cell formation. - It does not produce **beta-hCG**. *Liver* - The **liver** is a major organ of metabolism, detoxification, and protein synthesis. - It does not produce **beta-hCG**, which is specific to pregnancy. *Umbilical cord* - The **umbilical cord** connects the fetus to the placenta, facilitating nutrient and oxygen exchange. - It does not have endocrine functions and does not secrete **beta-hCG**.

Q: In a patient with ectopic tubal pregnancy which is the earliest to rupture?

Isthmus. ***Isthmus*** - The **isthmus** is the **narrowest part** of the fallopian tube with the **least distensibility** and thin muscular wall. - Due to its limited capacity to accommodate the growing pregnancy, ectopic pregnancies in the isthmus rupture **earliest**, typically between **6-8 weeks of gestation**. - Rupture is often severe due to the narrow lumen and limited ability to expand. *Ampulla* - The **ampulla** is the most common site for ectopic pregnancies (approximately **70%** of cases). - It is wider and more distensible than the isthmus, allowing the pregnancy to grow for a longer period. - Rupture typically occurs **later**, between **8-12 weeks of gestation**. *Interstitial* - The **interstitial** (or cornual) portion is located within the **uterine wall**, surrounded by myometrium and rich vascular supply. - This location allows significant distensibility, so rupture occurs **latest** among tubal sites, typically at **12-16 weeks of gestation**. - When rupture occurs, it is **most catastrophic** with severe hemorrhage and highest risk of **maternal morbidity and mortality** due to the vascular supply. *Infundibulum* - Ectopic pregnancies in the **infundibulum** or fimbrial end are very rare. - Due to the wide opening, these pregnancies typically present as **tubal abortion** through the fimbria rather than rupture. - The area is less muscular, making contained rupture uncommon.

Q: Adamantinoma affects

Tibia. ***Tibia*** - **Adamantinoma** is a rare, malignant bone tumor that almost exclusively affects the **tibia**, accounting for over 90% of cases. - It often presents as a **slow-growing mass** associated with pain and swelling in the shin. *Humerus* - While other primary bone tumors can affect the humerus, adamantinoma is **extremely rare** in this location. - The humerus is more commonly affected by tumors like **osteosarcoma** or **Ewing sarcoma**. *Femur* - The femur is a common site for various bone tumors, but **adamantinoma is not typically found** here. - Tumors like **osteosarcoma** and **chondrosarcoma** are much more prevalent in the femur. *Radius* - Similar to the humerus and femur, the radius is **not a characteristic location** for adamantinoma. - Tumors of the radius are generally less common than in the major long bones.

Q: AFP is a tumour marker for which of the following?

HCC. ***Correct Option: HCC*** - **Alpha-fetoprotein (AFP)** is the most widely recognized tumor marker for **Hepatocellular Carcinoma (HCC)**, the most common primary liver cancer [1] - Elevated AFP levels (>400 ng/mL) are highly suggestive of HCC and are used for **diagnosis, monitoring treatment response, and surveillance for recurrence** [1] - AFP is also elevated in **yolk sac tumors** and some **non-seminomatous germ cell tumors**, but HCC remains the primary clinical association [1] *Incorrect: Chordoma* - **Chordomas** are rare malignant bone tumors arising from notochord remnants, typically in the skull base or sacrum - **No specific tumor marker** is routinely used; brachyury (transcription factor) may be used as an immunohistochemical marker for diagnosis - AFP is not associated with chordomas *Incorrect: RCC* - **Renal Cell Carcinoma (RCC)** is the most common kidney malignancy - No highly specific tumor markers exist for RCC; occasionally **elevated LDH, alkaline phosphatase, or calcium** may be seen - AFP is not a marker for RCC *Incorrect: Oncocytoma* - **Renal oncocytoma** is a **benign** renal tumor composed of oncocytes (cells with abundant mitochondria) - Diagnosed primarily by **imaging and histology**, not serum markers - AFP has no role in oncocytoma diagnosis or monitoring **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 399-400.

Q: Cardiac event at the end of isometric relaxation phase:

Atrioventricular valves open. ***Atrioventricular valves open*** - This event marks the end of isometric relaxation, where ventricular pressure has dropped below atrial pressure, allowing the **mitral and tricuspid valves** to open and ventricular filling to begin. - During **isometric relaxation**, the ventricles relax without changing volume, causing a rapid drop in intraventricular pressure until it is overcome by atrial pressure. *Corresponds to T wave in ECG* - The **T wave** on an ECG represents **ventricular repolarization**, which occurs during the early part of ventricular diastole, *before* the end of isometric relaxation when the AV valves open. - The opening of AV valves occurs a bit later, as ventricular filling phase commences. *Atrioventricular valves close* - The closing of the **atrioventricular valves** (mitral and tricuspid) occurs at the beginning of **isovolumetric contraction (systole)**, not at the end of isometric relaxation (diastole). - This event marks the start of ventricular systole and is associated with the **first heart sound (S1)**. *Corresponds to peak of C wave in JVP* - The **C wave** in the jugular venous pressure (JVP) tracing corresponds to the bulging of the **tricuspid valve** into the right atrium during early ventricular systole, immediately after the AV valves close. - This event is distinct from the end of isometric relaxation, which occurs later in diastole, *before* atrial filling.

Q: Time cut-off for diagnosis of Priapism is?

4 hours. ***4 hours*** - A penile erection lasting longer than **4 hours** is the established cut-off for the diagnosis of **priapism**. - Prolonged erection beyond this duration can lead to **ischemia** and permanent cavernosal damage. *2 hours* - While concerning, an erection lasting 2 hours is typically not classified as priapism, which requires a longer duration to meet diagnostic criteria. - At this stage, the risk of significant ischemic injury is lower compared to longer durations. *3 hours* - An erection lasting 3 hours is still below the clinically defined threshold for priapism. - Although it warrants close monitoring, intervention is usually recommended once the 4-hour mark is reached. *1 hour* - An erection of 1 hour is generally considered a normal physiological response and does not meet the criteria for priapism. - This duration is insufficient to cause the microvascular damage and cellular changes associated with priapism.

Question 1

Which of the following is the most suitable anesthetic agent for use in dogs?

Accepted Answer

Propofol

Answer

Medetomidine hydrochloride

Answer

Ketamine

Answer

Midazolam

Question 2

Km increases, but Vmax remains same. This is which type of inhibition?

Accepted Answer

Competitive

Answer

Uncompetitive

Answer

Non-competitive

Answer

Irreversible

Question 3

Refractory Septic shock is defined as?

Accepted Answer

Shock persisting despite adequate fluid resuscitation and vasopressor support

Answer

Shock requiring mechanical ventilation and inotropic support

Answer

Shock with lactate levels >4 mmol/L despite treatment

Answer

Shock that does not respond to initial fluid bolus within 1 hour

Question 4

On ECG, ST segment elevation is seen in all of the following conditions EXCEPT:

Accepted Answer

Hypocalcemia

Answer

Acute pericarditis

Answer

Myocardial infarction

Answer

Left ventricular aneurysm

Question 5

Beta-hCG is secreted by:

Accepted Answer

Syncytiotrophoblast

Answer

Yolk sac

Answer

Liver

Answer

Umbilical cord

Question 6

In a patient with ectopic tubal pregnancy which is the earliest to rupture?

Accepted Answer

Isthmus

Answer

Infundibulum

Answer

Ampulla

Answer

Interstitial

Question 7

Adamantinoma affects

Accepted Answer

Tibia

Answer

Humerus

Answer

Femur

Answer

Radius

Question 8

AFP is a tumour marker for which of the following?

Accepted Answer

HCC

Answer

Chordoma

Answer

RCC

Answer

Oncocytoma

Question 9

Cardiac event at the end of isometric relaxation phase:

Accepted Answer

Atrioventricular valves open

Answer

Corresponds to T wave in ECG

Answer

Atrioventricular valves close

Answer

Corresponds to peak of C wave in JVP

Question 10

Time cut-off for diagnosis of Priapism is?

Accepted Answer

4 hours

Answer

2 hours

Answer

3 hours

Answer

1 hour

FMGE 2018

Anesthesiology

Biochemistry

Internal Medicine

Obstetrics and Gynecology

Orthopaedics

Pathology

Physiology

Surgery