Bowel obstruction UK Medical PG Practice Questions and MCQs
Practice UK Medical PG questions for Bowel obstruction. These multiple choice questions (MCQs) cover important concepts and help you prepare for your exams.
Bowel obstruction UK Medical PG Question 1: A 38-year-old man presents with acute onset severe lower back pain and bilateral leg weakness. He has saddle anesthesia and cannot urinate. What is the most appropriate immediate management?
- A. MRI lumbar spine
- B. Emergency surgical decompression (Correct Answer)
- C. High-dose steroids
- D. Catheter insertion
- E. Pain relief
Bowel obstruction Explanation: ***Emergency surgical decompression***
- This patient's presentation with acute severe lower back pain, bilateral leg weakness, **saddle anesthesia**, and inability to urinate is highly indicative of **Cauda Equina Syndrome (CES)**.
- **Emergency surgical decompression** is the most appropriate immediate management to relieve pressure on the compromised **sacral nerve roots** and prevent irreversible neurological deficits, including permanent loss of bladder, bowel, and sexual function.
*MRI lumbar spine*
- An **MRI lumbar spine** is essential for confirming the diagnosis of CES and identifying the exact cause of compression (e.g., massive disc herniation, tumor).
- However, obtaining an MRI, while necessary, should not delay the preparation for **emergency surgical decompression**, as timely intervention is critical for functional recovery.
*High-dose steroids*
- **High-dose steroids** are typically used to reduce inflammation and edema in certain compressive conditions, such as spinal cord injury or epidural compression due to malignancy.
- They are not the primary treatment for **mechanical compression** of the cauda equina, as they do not remove the underlying structural cause of the compression.
*Catheter insertion*
- **Catheter insertion** is an important supportive measure to manage the **urinary retention** and prevent bladder overdistension and damage.
- However, it addresses a symptom rather than the underlying neurological emergency and does not resolve the **spinal cord compression** itself.
*Pain relief*
- Providing adequate **pain relief** is crucial for patient comfort and is part of initial supportive care.
- However, focusing solely on pain relief delays the definitive and urgent surgical intervention required to treat the **neurological emergency** and preserve function.
Bowel obstruction UK Medical PG Question 2: A 31-year-old man presents with acute severe testicular pain. The pain started suddenly 4 hours ago. Doppler ultrasound shows absent blood flow. What is the expected salvage rate for this condition if treated at this time?
- A. >95%
- B. 80-90% (Correct Answer)
- C. 60-70%
- D. 40-50%
- E. <20%
Bowel obstruction Explanation: ***80-90%*** - Testicular torsion **salvage rates** are inversely proportional to the duration of **ischemia**, with optimal outcomes expected within the first 6 hours. - At 4 hours, a high **salvage rate** is still anticipated, typically falling within the 80-90% range, reflecting a good prognosis for timely intervention. * >95%* - While rates can approach 100% for interventions within **3 hours**, a 4-hour delay makes achieving greater than 95% less likely. - Maximal **testicular salvage** for absent blood flow requires extremely rapid surgical treatment, making earlier intervention crucial for these peak rates. *60-70%* - This salvage rate is more commonly associated with presentations occurring between **6 and 12 hours** after the onset of torsion. - Beyond 6 hours, the likelihood of irreversible damage to the **seminiferous tubules** significantly increases due to prolonged ischemia. *40-50%* - This lower rate indicates a longer duration of ischemia, typically seen when presentation is between **12 and 24 hours**. - Prolonged lack of **oxygenation** causes extensive testicular necrosis, often leading to the need for orchiectomy. *<20%* - This very low salvage rate applies to cases presenting more than **24 hours** after symptom onset. - At this stage, the testicle is almost universally non-viable due to **irreversible cellular damage** from prolonged ischemia.
Bowel obstruction UK Medical PG Question 3: A 26-year-old man presents with acute onset severe chest pain and dyspnea. He is tall and thin with marfanoid features. Chest X-ray shows a large right pneumothorax. What is the most appropriate management?
- A. Observation
- B. Needle aspiration
- C. Chest drain insertion (Correct Answer)
- D. Thoracotomy
- E. VATS procedure
Bowel obstruction Explanation: ***Chest drain insertion***- This is the standard definitive management for a **large** or **symptomatic** pneumothorax, especially given the patient's acute presentation with **severe chest pain** and **dyspnea**.- Insertion of a **tube thoracostomy** allows immediate and continuous decompression of the pleural space, which is critical for lung re-expansion and stabilization.*Observation*- Observation is reserved only for patients with a **small** (<2 cm apical rim) pneumothorax who are **asymptomatic** or clinically stable.- This patient is experiencing severe symptoms requiring prompt intervention, making observation an unsafe and inappropriate management choice.*Needle aspiration*- **Needle aspiration** (or simple aspiration) is typically reserved for smaller, asymptomatic, or minimally symptomatic **primary spontaneous pneumothoraces**.- This method has a lower success rate and is insufficient for effective decompression in a patient with a large, symptomatic pneumothorax and high risk features.*Thoracotomy*- **Thoracotomy** is a highly invasive open surgical approach, typically reserved for complicated, recurrent, or persistent air leak cases (e.g., failed VATS) or trauma.- This patient requires immediate stabilization and decompression, for which thoracotomy is disproportionately aggressive and unnecessary as a primary measure.*VATS procedure*- The **Video-Assisted Thoracoscopic Surgery (VATS)** procedure is an elective operative measure used for the prevention of recurrence (e.g., bullectomy and **pleurodesis**).- It is not the appropriate emergency treatment for the acute decompression of a symptomatic pneumothorax.
Bowel obstruction UK Medical PG Question 4: A 27-year-old man presents with acute onset severe chest pain and dyspnea. He is tall and thin with a marfanoid habitus. Chest X-ray shows a large left-sided pneumothorax. What is the most appropriate management?
- A. Observation
- B. Needle aspiration
- C. Chest drain insertion (Correct Answer)
- D. Thoracotomy
- E. VATS procedure
Bowel obstruction Explanation: ***Chest drain insertion*** - A **large pneumothorax** causing acute symptoms (severe chest pain and dyspnea) requires immediate air removal. A **chest drain (tube thoracostomy)** is the most appropriate and definitive management for this.- The patient's **tall, thin build** and **marfanoid habitus** increase the risk for **Primary Spontaneous Pneumothorax (PSP)**, and a symptomatic large pneumothorax in such a patient mandates chest tube placement according to guidelines.*Observation*- **Observation** is generally reserved for **small pneumothoraces (apex to cupola distance <2 cm)** in hemodynamically stable patients with minimal symptoms.- This patient has a **large pneumothorax** with **severe chest pain and dyspnea**, making observation an unsuitable and potentially dangerous approach.*Needle aspiration*- **Needle aspiration** is typically used for **small to moderate** pneumothoraces in stable patients, often as an initial, less invasive step.- Given the **large size** of the pneumothorax and the patient's acute symptoms and Marfanoid habitus, a chest drain provides more reliable and sustained decompression and reduces recurrence risk more effectively than needle aspiration.*Thoracotomy*- **Thoracotomy** is a highly invasive open surgical procedure, not the first-line treatment for an acute, primary spontaneous pneumothorax.- It is usually reserved for **complex cases**, such as recurrent pneumothorax after less invasive surgeries, persistent air leaks, or situations where VATS is contraindicated.*VATS procedure*- The **Video-Assisted Thoracoscopic Surgery (VATS)** procedure is primarily indicated for the *prevention of recurrence* (e.g., pleurodesis, bullectomy) or for managing complications *after initial stabilization* with a chest drain.- It is an elective surgical intervention, not the immediate management for an acute, symptomatic large pneumothorax requiring urgent decompression.
Bowel obstruction UK Medical PG Question 5: A 46-year-old man presents with sudden onset severe "tearing" chest pain radiating to his back. His blood pressure is 180/100 mmHg in the right arm and 120/80 mmHg in the left arm. What is the most likely diagnosis?
- A. Myocardial infarction
- B. Aortic dissection (Correct Answer)
- C. Pulmonary embolism
- D. Pericarditis
- E. Pneumothorax
Bowel obstruction Explanation: ***Aortic dissection*** - The presentation of **sudden onset, severe, "tearing" chest pain** radiating to the back is a classic symptom triad for aortic dissection. - The **significant inter-arm systolic blood pressure differential** (e.g., >20 mmHg difference) is a critical finding, indicating potential compromise of a major branch vessel (like the subclavian artery) due to the dissection flap. *Myocardial infarction* - MI pain is typically described as **crushing** or **pressure-like**, radiating to the neck, jaw, or left arm, not typically
Bowel obstruction UK Medical PG Question 6: A 39-year-old man with ulcerative colitis presents with a 5-day history of increasing bloody diarrhea (>10 times daily), abdominal pain, and fever. Examination shows a distended tender abdomen with reduced bowel sounds. Abdominal radiograph shows transverse colon diameter of 7.5 cm with loss of haustrations and mucosal islands. Blood tests: Hb 89 g/L, WBC 18.4×10⁹/L, CRP 245 mg/L, albumin 22 g/L, potassium 3.1 mmol/L. Despite 72 hours of IV hydrocortisone, broad-spectrum antibiotics, and optimization, he remains systemically unwell with persistent fever and 8 bloody stools in 24 hours. What is the most appropriate next step?
- A. Add infliximab rescue therapy and continue intensive medical management
- B. Urgent flexible sigmoidoscopy to assess disease severity
- C. Commence ciclosporin as second-line medical therapy
- D. Emergency subtotal colectomy with end ileostomy (Correct Answer)
- E. Continue IV corticosteroids for total of 7 days before considering surgery
Bowel obstruction Explanation: ***Emergency subtotal colectomy with end ileostomy***
- This patient has **toxic megacolon** (transverse colon >6 cm on radiograph) and meets **Truelove and Witts criteria** for acute severe ulcerative colitis, failing to improve after 72 hours of intensive medical therapy.
- Surgical intervention is mandatory when there is **clinical deterioration**, signs of peritonitis, or persistent dilatation despite treatment to prevent **perforation** and high mortality.
*Add infliximab rescue therapy and continue intensive medical management*
- While **infliximab** is a valid rescue therapy for acute severe UC, it is generally contraindicated or highly risky in the presence of **toxic megacolon** and systemic deterioration due to the increased risk of perforation.
- Delaying surgery to attempt further medical therapy in a patient with a colon diameter of 7.5 cm and persistent systemic unwellness significantly increases the risk of **colonic perforation** and sepsis.
*Urgent flexible sigmoidoscopy to assess disease severity*
- The diagnosis of **toxic megacolon** is already established via **abdominal radiograph** and clinical findings, and disease severity is evident from inflammatory markers and persistent symptoms.
- Performing a sigmoidoscopy in the setting of extreme colonic dilatation is dangerous as it increases the risk of **iatrogenic perforation** due to air insufflation.
*Commence ciclosporin as second-line medical therapy*
- **Ciclosporin** is used as rescue therapy in steroid-refractory UC but, like infliximab, is inappropriate when **toxic megacolon** and clear surgical indications are present, especially with systemic unwellness.
- The patient's **hypoalbuminemia** and systemic toxicity make him a poor candidate for further medical delay; surgical consultation should have occurred given the failure of initial intensive therapy.
*Continue IV corticosteroids for total of 7 days before considering surgery*
- Management guidelines (e.g., **Travis criteria**) dictate that response to IV steroids for acute severe UC should be assessed at **72 hours**; delayed surgery beyond this window in non-responders increases morbidity and mortality.
- Waiting 7 days in a patient with **toxic megacolon** and persistent severe symptoms despite steroids allows progression to **sepsis**, bowel rupture, and significantly worse outcomes.
Bowel obstruction UK Medical PG Question 7: A 44-year-old woman presents with sudden onset severe right upper quadrant pain radiating to the right shoulder tip. She has had previous episodes of biliary colic. Ultrasound shows gallstones with gallbladder wall thickening (6 mm), pericholecystic fluid, and a positive sonographic Murphy's sign. Blood tests show WBC 15.3×10⁹/L, CRP 78 mg/L. What is the optimal timing for cholecystectomy?
- A. Immediate emergency cholecystectomy within 6 hours
- B. Early laparoscopic cholecystectomy within 72 hours of symptom onset (Correct Answer)
- C. Conservative management with antibiotics followed by interval cholecystectomy at 6-8 weeks
- D. Percutaneous cholecystostomy followed by delayed cholecystectomy after 3 months
- E. Urgent ERCP within 24 hours followed by cholecystectomy during same admission
Bowel obstruction Explanation: ***Early laparoscopic cholecystectomy within 72 hours of symptom onset***- The clinical presentation of severe right upper quadrant pain radiating to the shoulder, previous biliary colic, fever, elevated WBC and CRP, alongside ultrasound findings of gallstones, gallbladder wall thickening, pericholecystic fluid, and a positive sonographic Murphy's sign, strongly indicates **acute cholecystitis**.- **Early laparoscopic cholecystectomy (ELC)** within 72 hours of symptom onset is the **gold standard** for acute cholecystitis, as it reduces hospital stay, prevents recurrence, and allows for easier dissection of tissue planes before dense inflammatory adhesions develop.*Immediate emergency cholecystectomy within 6 hours*- While early intervention is crucial, an **immediate emergency operation** within 6 hours is typically reserved for severe, complicated cases such as **gallbladder perforation**, emphysematous cholecystitis, or rapidly deteriorating sepsis.- For uncomplicated acute cholecystitis, a brief period for **fluid resuscitation** and **antibiotic administration** is usually preferred to stabilize the patient before definitive surgery.*Conservative management with antibiotics followed by interval cholecystectomy at 6-8 weeks*- This
Bowel obstruction UK Medical PG Question 8: A 76-year-old man with known colorectal adenocarcinoma presents with a 72-hour history of absolute constipation and abdominal distension. CT shows dilated colon up to 11 cm in diameter at the caecum with an obstructing sigmoid tumour. The caecal wall appears thinned. He has multiple comorbidities including severe COPD and recent myocardial infarction 8 weeks ago. What is the most appropriate management strategy?
- A. Emergency subtotal colectomy with end ileostomy
- B. Hartmann's procedure with sigmoid resection and end colostomy (Correct Answer)
- C. Endoscopic stent placement across obstructing tumour as bridge to surgery
- D. Proximal defunctioning transverse loop colostomy without tumour resection
- E. On-table lavage with primary resection and anastomosis
Bowel obstruction Explanation: ***Hartmann's procedure with sigmoid resection and end colostomy***
- This procedure is the safest emergency option as it resolves the **mechanical obstruction** and relieves the pressure on the **dilated caecum (11 cm)**, which is at high risk of perforation due to the thinned wall.
- It avoids a high-risk **primary anastomosis** in an unprepared, obstructed bowel, minimizing operative time and physiological stress for a patient with significant comorbidities like **recent MI** and **severe COPD**.
*Emergency subtotal colectomy with end ileostomy*
- This is a more extensive and physiologically demanding operation that carries a significantly higher **morbidity and mortality** rate in a frail patient with severe comorbidities.
- While it addresses the entire colon, it is generally reserved for diffuse colonic disease or actual perforation/ischemia of the right colon, not solely for a distal obstruction with impending rupture.
*Endoscopic stent placement across obstructing tumour as bridge to surgery*
- Stenting is **contraindicated** when there are signs of **impending perforation**, such as a caecal diameter >10 cm and a thinned wall, as it may not achieve rapid enough decompression.
- The procedure carries a risk of **diastatic caecal rupture** and has been associated with poor oncological outcomes in emergency settings.
*Proximal defunctioning transverse loop colostomy without tumour resection*
- This procedure does not remove the **primary malignancy**, leaving the source of obstruction and potential future complications in situ.
- A loop colostomy often provides inadequate decompression of a massively dilated caecum, especially if the **ileocaecal valve** is competent.
*On-table lavage with primary resection and anastomosis*
- This requires a prolonged operative time and stable hemodynamics, making it unsuitable for a patient with a **recent myocardial infarction** and severe lung disease.
- There is a very high risk of **anastomotic leak** in the setting of acute obstruction and an unprepared bowel, which would be catastrophic for this high-risk patient.
Bowel obstruction UK Medical PG Question 9: A 67-year-old man presents with a 6-hour history of sudden onset severe epigastric pain. Erect chest radiograph shows free gas under the diaphragm. At laparotomy, a 1 cm perforated anterior duodenal ulcer is identified with minimal peritoneal contamination. What is the most appropriate surgical management?
- A. Partial gastrectomy with Billroth II reconstruction
- B. Truncal vagotomy and pyloroplasty with ulcer excision
- C. Whipple's procedure to ensure complete resection of ulcer-bearing area
- D. Simple closure with omental patch (Graham patch) and peritoneal lavage (Correct Answer)
- E. Ulcer excision with primary closure and highly selective vagotomy
Bowel obstruction Explanation: ***Simple closure with omental patch (Graham patch) and peritoneal lavage***- This is the **standard of care** for a **perforated duodenal ulcer** as it is quick, safe, and effective in an emergency setting, especially with **minimal peritoneal contamination**.- The procedure involves closing the perforation, reinforced with an **omentum patch** (Graham patch), and then **lavaging the peritoneal cavity** to reduce infection, followed by **H. pylori eradication** and **PPIs**.*Partial gastrectomy with Billroth II reconstruction*- This is a **major resective procedure** with high morbidity and is **rarely indicated** for acute perforated duodenal ulcers.- It is typically reserved for **malignant gastric ulcers**, intractable bleeding, or severe **gastric outlet obstruction** from chronic ulcer disease, not for acute perforation.*Truncal vagotomy and pyloroplasty with ulcer excision*- Historically, **vagotomy** was performed to reduce acid secretion, but it has largely been replaced by effective **pharmacological agents** (PPIs) for ulcer disease.- These complex anti-secretory procedures add significant **operative time** and risk postoperative complications like **dumping syndrome** or **diarrhea**, making them unsuitable for an acute emergency.*Whipple's procedure to ensure complete resection of ulcer-bearing area*- A **Whipple's procedure (pancreaticoduodenectomy)** is an extremely radical operation primarily indicated for **periampullary malignancies** (e.g., pancreatic head cancer).- Performing this extensive surgery for a benign 1 cm duodenal perforation is **grossly inappropriate** and carries an unacceptably high **morbidity and mortality** risk.*Ulcer excision with primary closure and highly selective vagotomy*- While **highly selective vagotomy** aims to reduce acid secretion with fewer side effects than truncal vagotomy, it is a **technically demanding** procedure and **unnecessary** in the acute setting of a perforated ulcer.- The immediate priority in an acute perforation is to **secure the leak** and manage peritonitis, rather than performing a complex elective-style anti-secretory procedure.
Bowel obstruction UK Medical PG Question 10: A 53-year-old woman undergoes CT for suspected appendicitis. The appendix appears normal, but CT shows streaky infiltration of mesenteric fat with a hyperdense ring surrounding a central hypodense nodule in the right lower quadrant, described as a 'fat ring sign'. The patient is haemodynamically stable with localized tenderness. What is the most appropriate management?
- A. Emergency appendicectomy due to early appendicitis not yet showing on CT
- B. Conservative management with analgesia and observation as this represents epiploic appendagitis (Correct Answer)
- C. Urgent laparotomy for suspected mesenteric vein thrombosis
- D. Right hemicolectomy to exclude underlying colonic malignancy
- E. Broad-spectrum antibiotics for presumed bacterial peritonitis
Bowel obstruction Explanation: ***Conservative management with analgesia and observation as this represents epiploic appendagitis***
- The **'fat ring sign'** (a hyperdense ring around a hypodense nodule) on CT is pathognomonic for **epiploic appendagitis**, a self-limiting inflammatory condition.
- This condition is caused by **torsion or venous thrombosis** of the epiploic appendages and typically resolves within 3 to 14 days without surgical intervention.
*Emergency appendicectomy due to early appendicitis not yet showing on CT*
- CT has a very **high sensitivity** for appendicitis, and in this case, the appendix was explicitly described as **normal**.
- Pursuing surgery for a benign condition like epiploic appendagitis would lead to **unnecessary operative risks** and complications.
*Urgent laparotomy for suspected mesenteric vein thrombosis*
- **Mesenteric vein thrombosis** usually presents with severe, diffuse abdominal pain out of proportion to physical findings and systemic illness, not localized tenderness.
- CT findings for thrombosis would show **filling defects** in the mesenteric veins and signs of bowel ischemia rather than localized fat ring signs.
*Right hemicolectomy to exclude underlying colonic malignancy*
- A **right hemicolectomy** is a radical surgical procedure reserved for confirmed malignancy or severe inflammatory bowel disease, which is not indicated by a localized fat inflammation.
- While malignancy can mimic abdominal pain, the **specific CT features** described are distinct for a benign process and do not justify major resection.
*Broad-spectrum antibiotics for presumed bacterial peritonitis*
- Secondary **peritonitis** would typically present with generalized guarding, rebound tenderness, and systemic signs such as **fever and tachycardia**.
- Epiploic appendagitis is a **sterile inflammatory process**, so antibiotics are generally not required unless a secondary infection is suspected.
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