Gastrointestinal perforation US Medical PG Practice Questions and MCQs
Practice US Medical PG questions for Gastrointestinal perforation. These multiple choice questions (MCQs) cover important concepts and help you prepare for your exams.
Gastrointestinal perforation US Medical PG Question 1: A 66-year-old man is brought to the emergency department after a motor vehicle accident. The patient was a restrained passenger in a car that was struck on the passenger side while crossing an intersection. In the emergency department, he is alert and complaining of abdominal pain. He has a history of hyperlipidemia, gastroesophageal reflux disease, chronic kidney disease, and perforated appendicitis for which he received an interval appendectomy four years ago. His home medications include rosuvastatin and lansoprazole. His temperature is 99.2°F (37.3°C), blood pressure is 120/87 mmHg, pulse is 96/min, and respirations are 20/min. He has full breath sounds bilaterally. He is tender to palpation over the left 9th rib and the epigastrium. He is moving all four extremities. His FAST exam reveals fluid in Morrison's pouch.
This patient is most likely to have which of the following additional signs or symptoms?
- A. Pain radiating to the back
- B. Gross hematuria
- C. Muffled heart sounds
- D. Free air on chest radiograph
- E. Shoulder pain (Correct Answer)
Gastrointestinal perforation Explanation: ***Shoulder pain***
- The presence of **fluid in Morrison's pouch** (hepatorenal recess) on FAST exam indicates **intra-abdominal bleeding**, likely from a liver or spleen injury.
- **Diaphragmatic irritation** due to intra-abdominal hemorrhage often manifests as referred **shoulder pain** (Kehr's sign), especially on the left side with splenic injury or right side with liver injury.
*Pain radiating to the back*
- While pancreatic injury can cause pain radiating to the back, the primary finding of **fluid in Morrison's pouch** points towards hemoperitoneum, less specifically to pancreatic trauma.
- Significant pancreatic injury would likely involve more severe abdominal tenderness and potentially elevated **amylase/lipase**, which are not mentioned here.
*Gross hematuria*
- **Gross hematuria** would suggest a **renal or urologic injury**, but the patient's primary finding is intra-abdominal fluid in Morrison's pouch, which is more indicative of solid organ injury like the liver or spleen.
- Though concurrent injuries are possible in trauma, hepatorenal fluid points specifically to **hemoperitoneum**, not necessarily kidney damage.
*Muffled heart sounds*
- **Muffled heart sounds** are a component of **Beck's triad** (along with hypotension and jugular venous distension), indicative of **cardiac tamponade** due to fluid around the heart.
- There is no clinical information in the stem suggestive of cardiac injury or tamponade; the fluid is specifically mentioned in the abdomen.
*Free air on chest radiograph*
- **Free air on chest radiograph** (pneumoperitoneum) indicates a **perforated hollow viscus**, such as the bowel or stomach.
- The FAST exam finding of fluid in Morrison's pouch is characteristic of **hemoperitoneum** from a solid organ injury, not free air from a perforation.
Gastrointestinal perforation US Medical PG Question 2: A 52-year-old man is brought to the emergency department with severe epigastric discomfort and left-sided chest pain radiating to the back that began after waking up. He has also vomited several times since the pain began. He underwent an esophagogastroduodenoscopy the previous day for evaluation of epigastric pain. He has ischemic heart disease and underwent a coronary angioplasty 3 years ago. His mother died of pancreatic cancer when she was 60 years old. His current medications include aspirin, clopidogrel, metoprolol, ramipril, and rosuvastatin. He is pale, anxious, and diaphoretic. His temperature is 37.9°C (100.2°F), pulse is 140/min, respirations are 20/min, and blood pressure is 100/60 mm Hg in his upper extremities and 108/68 mm Hg in his lower extremities. Pulse oximetry on room air shows oxygen saturation at 98%. An S4 is audible over the precordium, in addition to crepitus over the chest. Abdominal examination shows tenderness to palpation in the epigastric area. Serum studies show an initial Troponin I level of 0.031 ng/mL (N < 0.1 ng/mL) and 0.026 ng/mL 6 hours later. A 12-lead ECG shows sinus tachycardia with nonspecific ST-T changes. Which of the following is the most likely diagnosis?
- A. Esophageal perforation (Correct Answer)
- B. Pneumothorax
- C. Aortic dissection
- D. Acute pancreatitis
- E. Acute myocardial infarction
Gastrointestinal perforation Explanation: ***Esophageal perforation***
- The patient's recent **esophagogastroduodenoscopy (EGD)**, followed by severe epigastric and chest pain radiating to the back, vomiting, and **subcutaneous emphysema (crepitus)**, is highly suggestive of esophageal perforation.
- **Mackler's triad** (vomiting, chest pain, and subcutaneous emphysema) is characteristic, and the overall clinical picture, including stable troponins and ECG, rules out cardiac events.
*Pneumothorax*
- While pneumothorax can cause chest pain and dyspnea, it typically presents with **diminished breath sounds** and **hyperresonance** on percussion, not crepitus over the chest (which indicates subcutaneous emphysema).
- A recent EGD is not a direct risk factor for pneumothorax, and the pain radiation to the back is less typical for a simple pneumothorax.
*Aortic dissection*
- Aortic dissection presents with sudden, **excruciating tearing chest pain** radiating to the back, and can cause a pulse deficit or **blood pressure differential** between limbs.
- While a slight BP differential is noted (100/60 vs 108/68), it's not significant enough for dissection, and the crepitus makes this diagnosis less likely without other definitive signs.
*Acute pancreatitis*
- Acute pancreatitis causes severe epigastric pain radiating to the back and vomiting, similar to this presentation.
- However, the presence of **crepitus** (subcutaneous emphysema) and a recent EGD makes esophageal perforation a more likely diagnosis, as EGD is not a typical trigger for acute pancreatitis.
*Acute myocardial infarction*
- The patient has risk factors for cardiac disease, and initial symptoms like chest pain and diaphoresis could suggest an MI.
- However, the **normal serial troponin levels** and **nonspecific ECG changes** rule out an acute myocardial infarction, especially given the presence of crepitus.
Gastrointestinal perforation US Medical PG Question 3: A 51-year-old man with a recent diagnosis of peptic ulcer disease currently treated with an oral proton pump inhibitor twice daily presents to the urgent care center complaining of acute abdominal pain which began suddenly less than 2 hours ago. On physical exam, you find his abdomen to be mildly distended, diffusely tender to palpation, and positive for rebound tenderness. Given the following options, what is the next best step in patient management?
- A. Serum gastrin level
- B. Urgent CT abdomen and pelvis (Correct Answer)
- C. H. pylori testing
- D. Abdominal radiographs
- E. Upper endoscopy
Gastrointestinal perforation Explanation: ***Urgent CT abdomen and pelvis***
- The sudden onset of severe abdominal pain, diffuse tenderness, and **rebound tenderness** in a patient with a history of peptic ulcer disease (PUD) suggests a **perforated ulcer**, which is a surgical emergency.
- A CT scan is the **most sensitive imaging modality** for detecting **free air** (pneumoperitoneum) and can confirm the diagnosis with >95% sensitivity, helping to localize the perforation and identify complications such as abscess formation.
- CT also helps evaluate alternative diagnoses in the acute abdomen and provides detailed anatomic information for surgical planning.
*Serum gastrin level*
- This test is primarily used in the diagnosis of **Zollinger-Ellison syndrome**, a rare condition characterized by gastrinomas leading to severe, refractory PUD.
- It is not indicated in an acute emergency setting with signs of perforation, as it would delay critical diagnostic imaging and management.
*H. pylori testing*
- **_H. pylori_ infection** is a common cause of PUD, but testing for it is part of routine initial management or follow-up for chronic disease.
- Testing would not address the immediate life-threatening complication of suspected perforation and would delay definitive diagnosis.
*Abdominal radiographs*
- An upright chest X-ray or abdominal radiograph can detect **free air under the diaphragm** in cases of perforation and is a reasonable initial imaging test.
- However, plain radiographs have lower sensitivity (75-80%) compared to CT scan and may miss smaller perforations or provide insufficient information about the location and extent of injury.
- In modern practice with readily available CT, cross-sectional imaging is preferred for its superior diagnostic accuracy in evaluating the acute abdomen.
*Upper endoscopy*
- **Upper endoscopy** is a valuable diagnostic and therapeutic tool for stable PUD but is **absolutely contraindicated** in cases of suspected or confirmed hollow viscus perforation.
- Introducing an endoscope with air insufflation could worsen the perforation and lead to further contamination of the peritoneal cavity, increasing morbidity and mortality.
Gastrointestinal perforation US Medical PG Question 4: A 45-year-old man is brought to the emergency department because of severe abdominal pain for the past 2 hours. He has a 2-year history of burning epigastric pain that gets worse with meals. His pulse is 120/min, respirations are 22/min, and blood pressure is 60/40 mm Hg. Despite appropriate lifesaving measures, he dies. At autopsy, examination shows erosion of the right gastric artery. Perforation of an ulcer in which of the following locations most likely caused this patient's findings?
- A. Anterior duodenum
- B. Posterior duodenum
- C. Lesser curvature of the stomach (Correct Answer)
- D. Greater curvature of the stomach
- E. Fundus of the stomach
Gastrointestinal perforation Explanation: ***Lesser curvature of the stomach***
- Erosion of the **right gastric artery** by a gastric ulcer is characteristic of an ulcer located on the **lesser curvature of the stomach**.
- Ulcers in this location can erode into adjacent blood vessels, leading to **severe hemorrhage** as evidenced by the patient's **hypotension** and subsequent death.
*Anterior duodenum*
- Ulcers in the **anterior duodenum** typically present with **perforation into the peritoneal cavity**, leading to generalized peritonitis, not primarily hemorrhage from a major artery.
- While bleeding can occur, it's usually from smaller duodenal arteries and less commonly involves large arteries like the right gastric artery.
*Posterior duodenum*
- Ulcers in the **posterior duodenum** are known to erode into the **gastroduodenal artery**, leading to massive upper gastrointestinal bleeding.
- This is a distinct arterial involvement compared to the erosion of the right gastric artery.
*Greater curvature of the stomach*
- Ulcers on the **greater curvature of the stomach** are less common and often associated with malignancy.
- If they bleed, it would typically involve branches of the **gastroepiploic arteries**, not the right gastric artery.
*Fundus of the stomach*
- Ulcers in the **fundus** are rare.
- If a vessel were involved, it would typically be a short gastric artery, not the right gastric artery which courses along the lesser curvature.
Gastrointestinal perforation US Medical PG Question 5: A 52-year-old man comes to the physician because of a 3-month history of upper abdominal pain and nausea that occurs about 3 hours after eating and at night. These symptoms improve with eating. After eating, he often has a feeling of fullness and bloating. He has had several episodes of dark stools over the past month. He has smoked one pack of cigarettes daily for 40 years and drinks 2 alcoholic beverages daily. He takes no medications. His temperature is 36.4°C (97.5°F), pulse is 80/min, and blood pressure is 110/70 mm Hg. Abdominal examination shows epigastric tenderness with no guarding or rebound. Bowel sounds are normal. Which of the following treatments is most appropriate to prevent further complications of the disease in this patient?
- A. Intravenous vitamin B12 supplementation
- B. Truncal vagotomy
- C. Amoxicillin, clarithromycin, and omeprazole (Correct Answer)
- D. Fundoplication, hiatoplasty, and gastropexy
- E. Distal gastrectomy with gastroduodenostomy
Gastrointestinal perforation Explanation: ***Amoxicillin, clarithromycin, and omeprazole***
- This patient's symptoms (epigastric pain 3 hours after eating and at night, improvement with eating, dark stools) are highly suggestive of a **duodenal ulcer complicated by upper gastrointestinal bleeding**. The most common cause of duodenal ulcers is *H. pylori* infection.
- The recommended first-line treatment for *H. pylori* infection involves a triple therapy regimen, including two antibiotics (like **amoxicillin and clarithromycin**) to eradicate the bacteria and a **proton pump inhibitor (omeprazole)** to reduce acid production and promote ulcer healing.
*Intravenous vitamin B12 supplementation*
- This treatment is appropriate for **vitamin B12 deficiency**, which can occur in conditions like atrophic gastritis, pernicious anemia, or following gastric resections, but is not indicated for acute peptic ulcer disease and wouldn't address the primary pathology.
- There is no clinical indication in the patient's presentation (e.g., neurological symptoms, macrocytic anemia) to suggest a deficiency in vitamin B12.
*Truncal vagotomy*
- **Truncal vagotomy** is a surgical procedure that was historically performed to reduce gastric acid secretion by cutting the vagus nerve. It is rarely used now due to the effectiveness of medical therapies for peptic ulcer disease.
- This invasive surgical option is generally reserved for refractory cases of peptic ulcer disease not responsive to medical management, or when complications like uncontrolled bleeding or perforation necessitate surgical intervention.
*Fundoplication, hiatoplasty, and gastropexy*
- These surgical procedures are primarily used to treat **gastroesophageal reflux disease (GERD)** and **hiatal hernia**, not peptic ulcer disease.
- Fundoplication wraps the stomach fundus around the lower esophagus to reinforce the lower esophageal sphincter, addressing reflux symptoms which are not the primary complaint here.
*Distal gastrectomy with gastroduodenostomy*
- **Distal gastrectomy** is a major surgical procedure involving the removal of the distal part of the stomach. It is typically reserved for severe complications of peptic ulcer disease (e.g., perforation, obstruction, recurrent bleeding unresponsive to other treatments) or gastric cancer.
- While it might be considered in extreme cases of complicated peptic ulcer, it is not the initial or most appropriate treatment for preventing further complications in a patient who has yet to receive standard anti-*H. pylori* therapy.
Gastrointestinal perforation US Medical PG Question 6: A 65-year-old woman presents with severe abdominal pain and bloody diarrhea. Past medical history is significant for a myocardial infarction 6 months ago. The patient reports a 25-pack-year smoking history and consumes 80 ounces of alcohol per week. Physical examination shows a diffusely tender abdomen with the absence of bowel sounds. Plain abdominal radiography is negative for free air under the diaphragm. Laboratory findings show a serum amylase of 115 U/L, serum lipase 95 U/L. Her clinical condition deteriorates rapidly, and she dies. Which of the following would most likely be the finding on autopsy in this patient?
- A. Perforated appendicitis
- B. Small bowel ischemia (Correct Answer)
- C. Ulcerative colitis
- D. Acute pancreatitis
- E. Small bowel obstruction
Gastrointestinal perforation Explanation: ***Small bowel ischemia***
- The patient's history of **myocardial infarction**, **smoking**, and **alcohol abuse** are significant risk factors for **atherosclerosis** and vascular compromise. The rapid deterioration with **severe abdominal pain** out of proportion to physical findings, bloody diarrhea, and absence of bowel sounds, is classic for **mesenteric ischemia**.
- On autopsy, this typically reveals **necrotic segments of the bowel** due to a lack of blood supply, often associated with an occluded mesenteric artery or watershed ischemia.
*Perforated appendicitis*
- While it causes **severe abdominal pain** and peritonitis, it typically presents with **localized pain** in the right lower quadrant, often with fever and leukocytosis, which are not mentioned.
- **Bloody diarrhea** is not a common symptom of perforated appendicitis.
*Ulcerative colitis*
- This is a **chronic inflammatory bowel disease** that causes bloody diarrhea, but the acute, severe presentation with rapid clinical deterioration and absence of bowel sounds is more consistent with an acute vascular event.
- It usually presents with a history of **recurrent symptoms**, and while severe cases can lead to toxic megacolon, the patient's risk factors point elsewhere.
*Acute pancreatitis*
- This condition is characterized by **severe epigastric pain** radiating to the back, often with elevated amylase and lipase. While the patient has alcohol abuse, her amylase and lipase are only mildly elevated (115 U/L and 95 U/L respectively), which are not indicative of severe pancreatitis.
- **Bloody diarrhea** is not a typical symptom of acute pancreatitis.
*Small bowel obstruction*
- Presents with colicky abdominal pain, **vomiting**, and **abdominal distention**, often with **high-pitched bowel sounds** initially, followed by absence.
- While it can lead to bowel ischemia in severe cases (strangulation), bloody diarrhea and rapid deterioration are more directly indicative of primary ischemia rather than an uncomplicated mechanical obstruction.
Gastrointestinal perforation US Medical PG Question 7: A 50-year-old male presents to the emergency with abdominal pain. He reports he has had abdominal pain associated with meals for several months and has been taking over the counter antacids as needed, but experienced significant worsening pain one hour ago in the epigastric region. The patient reports the pain radiating to his shoulders. Vital signs are T 38, HR 120, BP 100/60, RR 18, SpO2 98%. Physical exam reveals diffuse abdominal rigidity with rebound tenderness. Auscultation reveals hypoactive bowel sounds. Which of the following is the next best step in management?
- A. Admission and observation
- B. Chest radiograph
- C. 12 lead electrocardiogram
- D. Abdominal CT scan (Correct Answer)
- E. Abdominal ultrasound
Gastrointestinal perforation Explanation: ***Abdominal CT scan***
- This patient presents with classic signs of a **perforated peptic ulcer**: sudden severe epigastric pain radiating to the shoulders (diaphragmatic irritation), fever, tachycardia, hypotension, and peritoneal signs (rigid abdomen with rebound tenderness).
- While the patient shows signs of **early shock** (BP 100/60, HR 120), he is **conscious and maintaining adequate oxygenation** (SpO2 98%), making him stable enough for rapid CT imaging.
- **Abdominal CT scan** is the **most sensitive and specific** test for detecting free air, identifying the location of perforation, and assessing for complications (abscess, contained perforation).
- CT provides **critical surgical planning information** about the extent and location of perforation, which can guide the surgical approach.
- This should be followed by **immediate surgical consultation** and preparation for emergency laparotomy.
*Chest radiograph*
- While an **upright chest X-ray** can detect free air under the diaphragm (pneumoperitoneum), it has **lower sensitivity** (70-80%) compared to CT scan (>95%).
- In a patient who is stable enough for imaging, **CT is preferred** as it provides more information for surgical planning.
- Chest X-ray would be the appropriate choice only if **CT is unavailable** or if the patient is **too unstable** to be transported to the CT scanner.
*Admission and observation*
- This patient has **acute peritonitis** from a likely perforated viscus, which is a **surgical emergency** requiring operative intervention.
- Observation would be inappropriate and dangerous, leading to **septic shock**, **multi-organ failure**, and death.
*12 lead electrocardiogram*
- While epigastric pain can sometimes be cardiac in origin, the **peritoneal signs** (rigid abdomen, rebound tenderness, hypoactive bowel sounds) clearly indicate an **intra-abdominal pathology**.
- The pain radiation to **both shoulders** (Kehr's sign) suggests diaphragmatic irritation from intraperitoneal air or fluid, not cardiac ischemia.
*Abdominal ultrasound*
- Ultrasound is useful for evaluating **solid organ injury**, **free fluid**, and conditions like **cholecystitis** or **appendicitis**.
- However, it is **poor at detecting free air** due to bowel gas artifact and has limited sensitivity for perforated viscus.
- It would not provide adequate information for this surgical emergency.
Gastrointestinal perforation US Medical PG Question 8: A 68-year-old man presents to the emergency department with left lower quadrant abdominal pain and fever for 1 day. He states during this time frame he has had weight loss and a decreased appetite. The patient had surgery for a ruptured Achilles tendon 1 month ago and is still recovering but is otherwise generally healthy. His temperature is 102°F (38.9°C), blood pressure is 154/94 mmHg, pulse is 90/min, respirations are 15/min, and oxygen saturation is 98% on room air. Physical exam is remarkable for an uncomfortable and thin man with left lower quadrant abdominal tenderness without rebound findings. Fecal occult test for blood is positive. Laboratory studies are ordered as seen below.
Hemoglobin: 10 g/dL
Hematocrit: 30%
Leukocyte count: 3,500/mm^3 with normal differential
Platelet count: 157,000/mm^3
Which of the following is the most appropriate next step in management?
- A. Ceftriaxone and metronidazole
- B. Ciprofloxacin and metronidazole
- C. Colonoscopy
- D. CT abdomen (Correct Answer)
- E. MRI abdomen
Gastrointestinal perforation Explanation: ***CT abdomen***
- A **CT scan of the abdomen and pelvis** is the most appropriate initial diagnostic step for acute left lower quadrant pain with fever, leukopenia, and a positive fecal occult blood test, as it can efficiently evaluate for **diverticulitis**, bowel perforation, or **colonic malignancy**.
- The patient's presentation with constitutional symptoms like **weight loss and decreased appetite** in an older male, along with signs of anemia and occult blood, raises concern for **colorectal cancer**, making imaging a critical next step to differentiate potential etiologies.
*Ceftriaxone and metronidazole*
- While this is a common antibiotic regimen for suspected **diverticulitis**, it should not be initiated without definitive imaging, especially given the patient's concerning systemic symptoms and signs of **anemia and occult bleeding**, which could indicate a more serious underlying condition.
- Empirical antibiotic therapy without a clear diagnosis could delay the identification of conditions like **colorectal cancer** or abscess, which require different management strategies.
*Ciprofloxacin and metronidazole*
- This is also a typical antibiotic combination for uncomplicated **diverticulitis**; however, giving antibiotics without confirmation of the diagnosis via imaging is inappropriate in this case due to the patient's **systemic symptoms** and signs of **GI bleeding**.
- Without imaging to rule out intestinal perforation or malignancy, starting antibiotics could mask symptoms or delay crucial diagnostic and therapeutic interventions.
*Colonoscopy*
- A **colonoscopy** is indicated to investigate the **positive fecal occult blood** and rule out colorectal malignancy, but it is generally *contraindicated* in the acute setting of suspected diverticulitis due to the risk of **perforation**.
- Imaging (like CT) should always precede colonoscopy when acute abdominal pain and inflammation are present to assess for safety and guide the timing of endoscopy.
*MRI abdomen*
- While **MRI provides excellent soft tissue delineation**, it is typically not the first-line imaging modality for acute abdominal pain presentations in the emergency department.
- **CT scans are faster, more readily available**, and provide comprehensive imaging of the bowel, mesentery, and surrounding structures, making them superior for initial evaluation of acute abdominal conditions like diverticulitis or perforation.
Gastrointestinal perforation US Medical PG Question 9: A 72-year-old female presents to the emergency department complaining of severe abdominal pain and several days of bloody diarrhea. Her symptoms began with intermittent bloody diarrhea five days ago and have worsened steadily. For the last 24 hours, she has complained of fevers, chills, and abdominal pain. She has a history of ulcerative colitis, idiopathic hypertension, and hypothyroidism. Her medications include hydrochlorothiazide, levothyroxine, and sulfasalazine.
In the ED, her temperature is 39.1°C (102.4°F), pulse is 120/min, blood pressure is 90/60 mmHg, and respirations are 20/min. On exam, the patient is alert and oriented to person and place, but does not know the day. Her mucus membranes are dry. Heart and lung exam are not revealing. Her abdomen is distended with marked rebound tenderness. Bowel sounds are hyperactive.
Serum:
Na+: 142 mEq/L
Cl-: 107 mEq/L
K+: 3.3 mEq/L
HCO3-: 20 mEq/L
BUN: 15 mg/dL
Glucose: 92 mg/dL
Creatinine: 1.2 mg/dL
Calcium: 10.1 mg/dL
Hemoglobin: 11.2 g/dL
Hematocrit: 30%
Leukocyte count: 14,600/mm^3 with normal differential
Platelet count: 405,000/mm^3
What is the next best step in management?
- A. Emergent colonoscopy
- B. Contrast enema
- C. Colectomy
- D. Plain abdominal radiograph
- E. Abdominal CT with IV contrast (Correct Answer)
Gastrointestinal perforation Explanation: ***Abdominal CT with IV contrast***
- The patient presents with **severe abdominal pain, bloody diarrhea, fever, hypotension, tachycardia, abdominal distension, rebound tenderness, and leukocytosis**, all suggestive of **toxic megacolon** complicating her ulcerative colitis.
- An **abdominal CT with IV contrast** is the most appropriate next step to confirm the diagnosis, assess the extent of colonic dilation and inflammation, and rule out complications like perforation.
*Emergent colonoscopy*
- **Colonoscopy** is generally **contraindicated** in suspected toxic megacolon due to the high risk of **perforation** of the severely inflamed and dilated colon.
- While it can diagnose ulcerative colitis, the current acute, severe presentation makes it too risky.
*Contrast enema*
- A **contrast enema** is also **contraindicated** in setting of potential **toxic megacolon** or suspected colonic perforation.
- The pressure from the contrast agent could worsen dilation or cause perforation in an already compromised colon.
*Colectomy*
- **Colectomy** is a surgical intervention reserved for cases of **toxic megacolon** that **fail medical management** or when there is evidence of **perforation** or **ischemia**.
- It is not the *immediate* next step in management without further imaging and attempts at medical stabilization.
*Plain abdominal radiograph*
- A plain abdominal radiograph can show colonic dilation and air-fluid levels, which are indicative of toxic megacolon; however, it has **limited ability to assess the extent of inflammation**, detect complications like **perforation**, or rule out other intra-abdominal pathologies.
- It might be a useful initial screen but is not as comprehensive as a CT scan, especially when a definitive diagnosis and management plan is needed.
Gastrointestinal perforation US Medical PG Question 10: A 69-year-old male presents to the Emergency Department with bilious vomiting that started within the past 24 hours. His medical history is significant for hypertension, hyperlipidemia, and a myocardial infarction six months ago. His past surgical history is significant for a laparotomy 20 years ago for a perforated diverticulum. Most recently he had some dental work done and has been on narcotic pain medicine for the past week. He reports constipation and obstipation. He is afebrile with a blood pressure of 146/92 mm Hg and a heart rate of 116/min. His abdominal exam reveals multiple well-healed scars with distension but no tenderness. An abdominal/pelvic CT scan reveals dilated small bowel with a transition point to normal caliber bowel distally. When did the cause of his pathology commence?
- A. One week ago
- B. Six months ago
- C. 20 years ago (Correct Answer)
- D. At birth
- E. 24 hours ago
Gastrointestinal perforation Explanation: ***20 years ago***
- The patient's history of a **laparotomy 20 years ago** for a perforated diverticulum is the most likely cause of his current small bowel obstruction. **Adhesions** from prior abdominal surgery are the leading cause of small bowel obstruction.
- The CT scan finding of **dilated small bowel** with a **transition point** confirms a mechanical obstruction, and the operative scarring supports adhesions as the etiology.
*One week ago*
- While **narcotic pain medicine** can cause constipation and ileus, it typically leads to a more diffuse distention without a clear transition point characteristic of a mechanical obstruction.
- The development of a clear transition point on CT after only one week of narcotic use makes a mechanical obstruction from adhesions more likely than a pure narcotic-induced ileus.
*Six months ago*
- A **myocardial infarction** six months ago is not directly related to the development of a small bowel obstruction.
- While cardiac events can sometimes lead to mesenteric ischemia, the CT findings of a transition point are more indicative of a mechanical obstruction rather than ischemia.
*At birth*
- Congenital conditions causing small bowel obstruction, such as **atresia** or **malrotation**, typically present in infancy or early childhood.
- Given the patient's age and history of prior abdominal surgery, a congenital cause is highly unlikely.
*24 hours ago*
- The onset of symptoms within the past 24 hours describes the **acute presentation** of the obstruction, not its underlying cause.
- The obstruction itself developed over time due to a predisposing factor from his past medical history.
More Gastrointestinal perforation US Medical PG questions available in the OnCourse app. Practice MCQs, flashcards, and get detailed explanations.
