Pharmacology
1 questionsA patient undergoing a minor surgical procedure is given lignocaine injection. Assertion: Local anaesthetics act by blocking nerve conduction. Reason: Small fibers and non-myelinated fibers are blocked more easily than large myelinated fibers.
NEET-PG 2015 - Pharmacology NEET-PG Practice Questions and MCQs
Question 1241: A patient undergoing a minor surgical procedure is given lignocaine injection. Assertion: Local anaesthetics act by blocking nerve conduction. Reason: Small fibers and non-myelinated fibers are blocked more easily than large myelinated fibers.
- A. Assertion is false, but Reason is true
- B. Both Assertion and Reason are true, and Reason is not the correct explanation for Assertion (Correct Answer)
- C. Both Assertion and Reason are true, and Reason is the correct explanation for Assertion
- D. Assertion is true, but Reason is false
Explanation: ***Both Assertion and Reason are true, and Reason is NOT the correct explanation for Assertion*** - The **Assertion** is true: Local anesthetics (like lignocaine) block nerve conduction by inhibiting **voltage-gated sodium channels**, preventing the depolarization necessary for action potential propagation - The **Reason** is also true: Small diameter and non-myelinated fibers (like C and Aδ pain fibers) are blocked more easily than large myelinated fibers (like Aα motor fibers), which explains the **differential blockade** pattern seen clinically - However, the **Reason does NOT explain WHY** local anesthetics block nerve conduction—it describes **WHICH** nerve fibers are blocked preferentially. The mechanism of blocking conduction is sodium channel inhibition, not fiber size selectivity - The differential sensitivity is a consequence of fiber characteristics (surface area-to-volume ratio, number of nodes of Ranvier), not the explanation for the blocking mechanism itself *Both Assertion and Reason are true, and Reason is the correct explanation for Assertion* - While both statements are individually true, the Reason does not explain the **mechanism** by which local anesthetics block nerve conduction - The Reason addresses fiber **selectivity**, which is a separate pharmacological property from the **mechanism of action** (sodium channel blockade) *Assertion is true, but Reason is false* - The Assertion is demonstrably true—local anesthetics block nerve conduction - The Reason is also true—this is well-established pharmacology: autonomic (small) > sensory (medium) > motor (large) fiber blockade sequence *Assertion is false, but Reason is true* - The Assertion is fundamentally correct and represents the primary pharmacological action of local anesthetics - Blocking nerve conduction is the therapeutic goal of local anesthetic administration
Radiology
1 questionsRigler's sign is suggestive of?
NEET-PG 2015 - Radiology NEET-PG Practice Questions and MCQs
Question 1241: Rigler's sign is suggestive of?
- A. Pneumothorax
- B. Pneumoperitoneum (Correct Answer)
- C. Peritonitis
- D. Hemothorax
Explanation: ***Correct: Pneumoperitoneum*** - **Rigler's sign** (double wall sign) is the visualization of both the **inner (mucosal) and outer (serosal) surfaces** of the bowel wall on an abdominal X-ray. - This occurs when **free intraperitoneal air** outlines both sides of the bowel wall, making it a **pathognomonic sign of pneumoperitoneum**. - Commonly seen in **bowel perforation** from causes like peptic ulcer, trauma, or iatrogenic injury. *Incorrect: Pneumothorax* - Refers to air in the **pleural space** (thoracic cavity), not the peritoneal cavity. - Diagnosed on chest X-ray by the **visceral pleural line** with absent lung markings peripherally. - Completely different anatomical compartment from where Rigler's sign is observed. *Incorrect: Peritonitis* - Represents **inflammation of the peritoneum**, which is a clinical and pathological diagnosis. - While pneumoperitoneum from perforation can **lead to peritonitis**, Rigler's sign specifically indicates the **presence of free air**, not inflammation itself. - Peritonitis has no specific pathognomonic radiological sign like Rigler's. *Incorrect: Hemothorax* - Refers to **blood in the pleural cavity** (thoracic, not abdominal). - Appears as a **pleural effusion** with meniscus sign on chest X-ray. - Unrelated to abdominal radiological findings or free air.
Surgery
8 questionsWhich of the following statements about Gallbladder carcinoma is true?
Which of the following stoma is formed in Hartmann's procedure?
Most common site of colorectal carcinoma?
Which of the following characteristics is most accurate about Boerhaave syndrome?
Which of the following is true about Mallory-Weiss tear -
A 55 year old woman presented with history of recurrent episodes of right upper abdominal pain for the last one year. She presented to emergency with history of jaundice and fever for 2 days. On examination, the patient appeared toxic and had a blood pressure of 100/60 mmHg. She was started on intravenous antibiotics. Ultrasound of the abdomen showed presence of stones in the common bile duct. What would be the best treatment option for her -
A 70 year old male complaining of per rectal bleeding was diagnosed with rectal/anorectal cancer. The distal margin of the tumor was 5 cm from the anal verge. The treatment of choice would be -
Which of the following statements about Hirschsprung disease is incorrect?
NEET-PG 2015 - Surgery NEET-PG Practice Questions and MCQs
Question 1241: Which of the following statements about Gallbladder carcinoma is true?
- A. Carries a good prognosis
- B. Gallstones may be a predisposing factor (Correct Answer)
- C. Commonly squamous cell carcinoma
- D. Jaundice is rare
Explanation: ***Gallstones may be a predisposing factor*** - The chronic inflammation and irritation caused by **gallstones (cholelithiasis)** are considered major risk factors for the development of gallbladder carcinoma. - Approximately 70-90% of patients with gallbladder carcinoma also have **cholelithiasis**, suggesting a strong association. *Carries a good prognosis* - Gallbladder carcinoma generally has a **poor prognosis** due to its asymptomatic nature in early stages and aggressive local invasion. - Most cases are diagnosed at an advanced stage, leading to a **low 5-year survival rate**. *Commonly squamous cell carcinoma* - The vast majority of gallbladder carcinomas are **adenocarcinomas** (around 90%), arising from the glandular epithelium. - **Squamous cell carcinoma** is rare, accounting for only a small percentage of cases. *Jaundice is rare* - **Jaundice** is a common symptom in advanced gallbladder carcinoma, often indicating obstruction of the biliary ducts. - It arises when the tumor invades or compresses the **common bile duct**, leading to bilirubin backup.
Question 1242: Which of the following stoma is formed in Hartmann's procedure?
- A. End Colostomy (Correct Answer)
- B. End Ileostomy
- C. Loop Ileostomy
- D. Caecostomy
Explanation: ***End Colostomy*** - Hartmann's procedure involves resection of a diseased segment of the **colon**, typically the sigmoid colon, with the creation of a **proximal colostomy** and closure of the distal rectal stump. - The proximal end of the colon is brought out through the abdominal wall to form a **stoma**, which is a type of end colostomy. *End Ileostomy* - An end ileostomy involves bringing the **ileum** (small intestine) to the abdominal wall, which is not part of the standard Hartmann's procedure. - This is typically performed after a **total colectomy** or in cases of severe Crohn's disease affecting the colon. *Loop Ileostomy* - A loop ileostomy involves bringing a **loop of the ileum** to the surface of the abdomen, creating two openings that are then joined together. - This is often a **temporary diversion** and does not involve resection of the colon in the same manner as Hartmann's procedure. *Caecostomy* - A caecostomy is a stoma created from the **cecum**, the beginning of the large intestine. - This is typically performed for various reasons such as **bowel decompression** or management of fecal incontinence, and is not a component of Hartmann's procedure.
Question 1243: Most common site of colorectal carcinoma?
- A. Ascending Colon
- B. Descending Colon
- C. Rectum
- D. Sigmoid Colon (Correct Answer)
Explanation: ***Sigmoid Colon*** - The **sigmoid colon** is the most common site for colorectal carcinoma, accounting for approximately **25%** of all cases. - This higher incidence is potentially due to its role in stool storage, leading to longer contact time with potential carcinogens. *Rectum* - While the rectum is a common site, it accounts for about **15-20%** of colorectal cancers, making it less frequent than the sigmoid colon. - Rectal cancers often present with **hematochezia** and changes in bowel habits. *Ascending Colon* - The **ascending colon** is less frequently affected, around **10-15%** of cases. - Tumors here are often associated with **iron deficiency anemia** due to chronic blood loss. *Descending Colon* - The **descending colon** is also less commonly affected, making up approximately **5-10%** of colorectal cancers. - Tumors in this segment may present with **obstruction** due to the narrower lumen.
Question 1244: Which of the following characteristics is most accurate about Boerhaave syndrome?
- A. Most cases follow a bout of heavy eating or drinking
- B. Perforation of the esophagus due to barotrauma
- C. Sudden severe chest pain is an early manifestation
- D. Most common site is left posterolateral aspect 3 - 5 cms above the gastroesophageal junction (Correct Answer)
Explanation: ***Most common site is left posterolateral aspect 3 - 5 cms above the gastroesophageal junction*** - This anatomical location represents the **most characteristic and specific feature** of Boerhaave syndrome, occurring in approximately **90% of cases**. - The **left posterolateral wall** at this site is inherently weaker due to fewer muscle fibers and represents the point of maximal stress during sudden pressure increases. *Most cases follow a bout of heavy eating or drinking* - While **heavy eating or drinking** often precedes the syndrome, this is a **precipitating factor** rather than a defining characteristic. - Many other conditions can follow heavy consumption, making this a **non-specific association** rather than a distinguishing feature. *Perforation of the esophagus due to barotrauma* - This describes the **pathophysiological mechanism** of Boerhaave syndrome but is essentially the **definition** of the condition itself. - While accurate, it doesn't distinguish specific characteristics that differentiate Boerhaave syndrome from other esophageal perforations. *Sudden severe chest pain is an early manifestation* - **Sudden severe chest pain** is indeed a common presenting symptom but represents a **clinical manifestation** rather than a characteristic feature. - This symptom can occur in many thoracic emergencies, making it **non-specific** for Boerhaave syndrome diagnosis.
Question 1245: Which of the following is true about Mallory-Weiss tear -
- A. It is a mucosal tear not extending through the muscle layer (Correct Answer)
- B. It is more common in women than men
- C. It is common in young individuals
- D. It is associated with achalasia cardia
Explanation: ***It is a mucosal tear not extending through the muscle layer*** - A **Mallory-Weiss tear** is defined as a longitudinal tear in the **mucosa** of the distal esophagus or proximal stomach. - These tears typically do not extend through the **muscularis propria** layer, distinguishing them from a Boerhaave syndrome, which is a full-thickness rupture. *It is more common in women than men* - Mallory-Weiss tears show a **male predominance** with a male-to-female ratio of approximately 2-4:1. - Risk factors like **alcohol use disorder** and forceful vomiting are more common in males, contributing to this gender distribution. *It is common in young individuals* - Mallory-Weiss tears are more common in **middle-aged to older individuals**, typically between 40 and 60 years old. - The condition is rare in young children or teenagers. *It is associated with achalasia cardia* - While both conditions affect the esophagus, there is **no direct causal association** between Mallory-Weiss tears and **achalasia cardia**. - Achalasia is a motility disorder, whereas Mallory-Weiss tears are caused by sudden increases in intra-abdominal pressure.
Question 1246: A 55 year old woman presented with history of recurrent episodes of right upper abdominal pain for the last one year. She presented to emergency with history of jaundice and fever for 2 days. On examination, the patient appeared toxic and had a blood pressure of 100/60 mmHg. She was started on intravenous antibiotics. Ultrasound of the abdomen showed presence of stones in the common bile duct. What would be the best treatment option for her -
- A. Open bile duct surgery for stone removal
- B. Lithotripsy for bile duct stones
- C. Laparoscopic cholecystectomy (gallbladder removal)
- D. Endoscopic Retrograde Cholangiopancreatography (ERCP) and bile duct stone extraction (Correct Answer)
Explanation: ***Endoscopic Retrograde Cholangiopancreatography (ERCP) and bile duct stone extraction*** - The patient presents with **Reynolds' pentad** (Charcot's triad - right upper abdominal pain, jaundice, fever - plus hypotension and toxic appearance/altered mental status), indicating severe acute **cholangitis with septic shock** due to common bile duct stones. - **ERCP with stone extraction** is the most appropriate initial treatment in this unstable patient to achieve rapid biliary decompression and remove the obstruction, which is life-saving in septic cholangitis. - This minimally invasive approach provides urgent drainage while minimizing surgical stress in a critically ill patient. *Laparoscopic cholecystectomy (gallbladder removal)* - While cholecystectomy addresses gallbladder stones, it does not directly remove **common bile duct stones** causing the current acute cholangitis. - Performing cholecystectomy alone in an acutely septic patient would not resolve the immediate life-threatening biliary obstruction. - Cholecystectomy can be considered later (interval cholecystectomy) after stabilization and ERCP. *Open bile duct surgery for stone removal* - This is a more invasive procedure with higher morbidity and mortality compared to ERCP for initial management of common bile duct stones, especially in an acutely ill, hemodynamically unstable patient. - **Open surgery** is typically reserved for cases where ERCP fails or is not feasible, or for complex cases requiring biliary reconstruction. *Lithotripsy for bile duct stones* - **Lithotripsy** (fragmenting stones) is not appropriate for initial management of acute cholangitis with sepsis, as it does not provide immediate biliary drainage. - It might be considered as an adjunct for very large or impacted stones during ERCP, but it's not the primary immediate treatment in this emergency setting.
Question 1247: A 70 year old male complaining of per rectal bleeding was diagnosed with rectal/anorectal cancer. The distal margin of the tumor was 5 cm from the anal verge. The treatment of choice would be -
- A. Palliative Radiotherapy
- B. Low anterior resection (Correct Answer)
- C. Local Excision
- D. Abdominoperineal resection
Explanation: ***Low anterior resection*** - A tumor located 5 cm from the anal verge is considered a **low rectal tumor**, which is typically amenable to a **low anterior resection** with sphincter preservation. - This procedure aims for complete tumor removal while preserving anal function, which is often achievable when the distal margin allows for a safe distal resection margin (usually 1-2 cm). *Palliative Radiotherapy* - This is typically reserved for patients with advanced, **unresectable disease** or those who are not candidates for surgery due to comorbidities, aiming to alleviate symptoms rather than cure. - The scenario describes a potentially resectable tumor, making curative surgery the preferred initial approach. *Abdominoperineal resection* - This procedure involves the removal of the rectum, anus, and creation of a permanent colostomy, typically reserved for very **low rectal tumors** that are extremely close to or involve the anal sphincter, and cannot safely achieve a negative distal margin with sphincter preservation. - A tumor 5 cm from the anal verge usually allows for a sphincter-sparing procedure like low anterior resection. *Local Excision* - **Local excision (transanal excision)** is suitable for very superficial, small, well-differentiated tumors without lymph node involvement, typically T1N0M0 tumors. - The question does not provide details on tumor depth or nodal status, but a 5 cm tumor usually indicates a need for a more comprehensive resection to ensure oncological clearance.
Question 1248: Which of the following statements about Hirschsprung disease is incorrect?
- A. The non-peristaltic affected segment is dilated (Correct Answer)
- B. Absence of ganglion cells in the involved segment
- C. Mainly presents in infancy
- D. Swenson, Duhamel, and Soave are surgical procedures for this condition
Explanation: ***The non-peristaltic affected segment is dilated*** - In Hirschsprung disease, the **aganglionic segment** is typically **constricted** and **narrow**, not dilated, due to continuous contraction without relaxation. - The healthy colon proximal to the affected segment becomes dilated due to the obstruction caused by the constricted, aganglionic segment. *Absence of Ganglion cells in the involved segment* - This statement is **correct**. Hirschsprung disease is fundamentally characterized by the **absence of intramural ganglion cells** (Meissner and Auerbach plexuses) in a segment of the distal colon. - This aganglionosis results in a failure of relaxation and normal peristalsis in the affected bowel segment. *Swenson, Duhamel, and Soave are surgical procedures for this condition* - This statement is **correct**. These are the classic and most common **pull-through surgical procedures** used to treat Hirschsprung disease. - They involve resecting the aganglionic segment and pulling the normal, ganglionated bowel down to the anus. *Mainly presents in infancy* - This statement is **correct**. Hirschsprung disease is primarily a **congenital condition** and is typically diagnosed in newborns and infants. - Common presenting symptoms include **failure to pass meconium** within the first 24-48 hours of life, abdominal distension, and bilious vomiting.