Diagnostic approach to acute abdomen US Medical PG Practice Questions and MCQs
Practice US Medical PG questions for Diagnostic approach to acute abdomen. These multiple choice questions (MCQs) cover important concepts and help you prepare for your exams.
Diagnostic approach to acute abdomen US Medical PG Question 1: 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)
Diagnostic approach to acute abdomen 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.
Diagnostic approach to acute abdomen US Medical PG Question 2: A 41-year-old woman is brought to the emergency department with the acute-onset of severe abdominal pain for the past 2 hours. She has a history of frequent episodes of vague abdominal pain, but they have never been this severe. Every time she has had pain, it would resolve after eating a meal. Her past medical history is otherwise insignificant. Her vital signs include: blood pressure 121/77 mm Hg, pulse 91/min, respiratory rate 21/min, and temperature 37°C (98.6°F). On examination, her abdomen is flat and rigid. Which of the following is the next best step in evaluating this patient’s discomfort and stomach pain by physical exam?
- A. Auscultate the abdomen (Correct Answer)
- B. Elicit shifting dullness of the abdomen
- C. Perform light palpation at the point of maximal pain
- D. Attempt to perform a deep, slow palpation with quick release
- E. Percuss the point of maximal pain
Diagnostic approach to acute abdomen Explanation: ***Auscultate the abdomen***
- Auscultation is typically performed first in an abdominal exam to assess **bowel sounds** and identify any bruits, as palpation and percussion can alter bowel sound characteristics.
- While the patient has **peritonitis (rigid abdomen)**, initial auscultation is still the logical starting point for a comprehensive physical examination.
*Elicit shifting dullness of the abdomen*
- **Shifting dullness** is used to detect **ascites**, which is not the primary concern given the acute onset of severe pain and rigid abdomen.
- This maneuver typically comes later in the abdominal examination, after initial auscultation and palpation.
*Perform light palpation at the point of maximal pain*
- Given the patient's **rigid abdomen**, suggesting peritonitis, performing palpation (even light) at the point of maximal pain could cause significant discomfort and is secondary to initial auscultation in the *sequence* of physical exam.
- While palpation is crucial, the standard order in an abdominal exam begins with auscultation to ensure unchanged bowel sounds.
*Attempt to perform a deep, slow palpation with quick release*
- This describes evaluating for **rebound tenderness**, a sign of peritonitis, which is indeed suggested by the rigid abdomen.
- However, just like light palpation, this maneuver is performed *after* auscultation and is likely to cause significant pain in a patient with a rigid abdomen, making it not the very next best step.
*Percuss the point of maximal pain*
- Percussion is typically used to assess for **gas, fluid, or organ size/tenderness**, but it is performed after auscultation and before deep palpation in a standard abdominal exam.
- In a patient with a **rigid abdomen**, percussion can also elicit severe pain, and it does not precede auscultation in the examination sequence.
Diagnostic approach to acute abdomen US Medical PG Question 3: A 52-year-old woman presents to the urgent care center with several hours of worsening abdominal discomfort with radiation to the back. The patient also complains of malaise, chills, nausea, and vomiting. Social history is notable for alcoholism. On physical exam, she is febrile to 39.5°C (103.1°F), and she is diffusely tender to abdominal palpation. Complete blood count is notable for 13,500 white blood cells, bilirubin 2.1, lipase 842, and amylase 3,210. Given the following options, what is the most likely diagnosis?
- A. Choledocholithiasis
- B. Ascending cholangitis
- C. Gallstone pancreatitis (Correct Answer)
- D. Cholelithiasis
- E. Acute cholecystitis
Diagnostic approach to acute abdomen Explanation: ***Gallstone pancreatitis***
- The patient presents with classic symptoms of **acute pancreatitis**: severe abdominal pain radiating to the back, nausea, vomiting, and markedly elevated **lipase (842)** and **amylase (3,210)**.
- The **key differentiating feature** is the elevated **bilirubin (2.1 mg/dL)**, which indicates biliary obstruction from a gallstone passing through or obstructing the ampulla of Vater.
- **Gallstone pancreatitis** is the most common cause of acute pancreatitis in women, and the combination of pancreatitis with hyperbilirubinemia strongly suggests a biliary etiology rather than alcoholic pancreatitis (which typically does not cause elevated bilirubin).
- While the patient has a history of alcoholism, the elevated bilirubin makes **gallstone pancreatitis** the most likely diagnosis.
*Choledocholithiasis*
- This refers to a stone in the **common bile duct**, which can cause biliary obstruction and elevated bilirubin.
- However, choledocholithiasis alone does not explain the **markedly elevated lipase and amylase**, which indicate pancreatic inflammation.
- Choledocholithiasis may be present as part of the pathophysiology, but the clinical picture is acute pancreatitis caused by the stone (gallstone pancreatitis).
*Ascending cholangitis*
- This serious bile duct infection presents with **Charcot's triad** (fever, jaundice, right upper quadrant pain) or **Reynolds' pentad** (adds altered mental status and hypotension).
- While the patient is febrile, she lacks **jaundice**, hypotension, or altered mental status.
- The **extremely elevated lipase and amylase** point to pancreatitis rather than cholangitis as the primary process.
*Cholelithiasis*
- This simply means **gallstones in the gallbladder**, which are often asymptomatic.
- The patient's acute presentation with fever, systemic symptoms, and markedly elevated pancreatic enzymes indicates a complication of gallstones (pancreatitis), not just their presence.
*Acute cholecystitis*
- This is **gallbladder inflammation**, typically presenting with right upper quadrant pain, fever, positive Murphy's sign, and leukocytosis.
- The **diffuse abdominal tenderness** (not localized to RUQ), pain radiating to the back, and **extremely elevated lipase and amylase** are characteristic of pancreatitis, not cholecystitis.
- Acute cholecystitis does not cause such dramatic elevations in pancreatic enzymes.
Diagnostic approach to acute abdomen US Medical PG Question 4: A 68-year-old woman is brought to the emergency department with intense abdominal pain for the past 2 hours. She has had 1 episode of bloody diarrhea recently. She has an 18-year history of diabetes mellitus. She was diagnosed with hypertension and ischemic heart disease 6 years ago. She is fully alert and oriented. Her temperature is 37.5°C (99.5°F), blood pressure is 145/90 mm Hg, pulse is 78/min, and respirations are 14/min. Abdominal examination shows mild generalized abdominal tenderness without guarding or rebound tenderness. An abdominal plain X-ray shows no abnormalities. Abdominal CT reveals colonic wall thickening and pericolonic fat stranding in the splenic curvature. Bowel rest, intravenous hydration, and IV antibiotics are initiated. Which of the following is the most important diagnostic evaluation at this time?
- A. Angiography
- B. Gastrografin-enhanced X-ray
- C. Laparotomy
- D. Inpatient observation
- E. Sigmoidoscopy (Correct Answer)
Diagnostic approach to acute abdomen Explanation: ***Sigmoidoscopy***
- The patient's presentation with acute abdominal pain, bloody diarrhea, history of cardiovascular disease, and CT findings consistent with **colonic wall thickening** and **pericolonic fat stranding** strongly suggests **ischemic colitis**.
- **Flexible sigmoidoscopy** allows for direct visualization of the colonic mucosa to confirm the diagnosis, assess the extent and severity of ischemia, and rule out other causes of colitis, such as inflammatory bowel disease or infection.
*Angiography*
- While angiography can identify mesenteric arterial occlusion, it is generally reserved for cases of acute mesenteric ischemia involving the superior mesenteric artery, which typically presents with more severe pain out of proportion to physical exam findings and less clear CT findings of colitis.
- In cases of ischemic colitis, where the primary concern is mucosal ischemia rather than immediate large vessel occlusion, angiography is usually not the first-line diagnostic.
*Gastrografin-enhanced X-ray*
- This study (also known as a **Gastrografin swallow or enema**) is primarily used to evaluate for **perforations** or **obstructions**, or to assess lumen integrity.
- It does not provide the mucosal detail necessary to diagnose or assess the severity of **ischemic colitis**, and the contrast agent itself could potentially exacerbate an inflamed bowel.
*Laparotomy*
- **Laparotomy** (surgical exploration) is an invasive procedure reserved for cases with signs of peritonitis, bowel perforation, or severe, unresponsive ischemia requiring surgical intervention.
- Given the patient's stable vital signs, mild tenderness, and lack of guarding or rebound, immediate surgical exploration is not warranted without further diagnostic steps.
*Inpatient observation*
- While inpatient observation is part of the initial management (bowel rest, IV fluids, antibiotics), it is not a **diagnostic evaluation** itself.
- The question asks for the most important diagnostic evaluation to determine the underlying cause and guide further management.
Diagnostic approach to acute abdomen US Medical PG Question 5: A 75-year-old man presents to the emergency department for abdominal pain. The patient states the pain started this morning and has been worsening steadily. He decided to come to the emergency department when he began vomiting. The patient has a past medical history of obesity, diabetes, alcohol abuse, and hypertension. His current medications include captopril, insulin, metformin, sodium docusate, and ibuprofen. His temperature is 104.0°F (40°C), blood pressure is 160/97 mmHg, pulse is 90/min, respirations are 15/min, and oxygen saturation is 98% on room air. Abdominal exam reveals left lower quadrant tenderness. Cardiac exam reveals a crescendo systolic murmur heard best by the right upper sternal border. Lab values are ordered and return as below.
Hemoglobin: 15 g/dL
Hematocrit: 42%
Leukocyte count: 19,500 cells/mm^3 with normal differential
Platelet count: 226,000/mm^3
Serum:
Na+: 139 mEq/L
Cl-: 101 mEq/L
K+: 4.4 mEq/L
HCO3-: 24 mEq/L
BUN: 22 mg/dL
Glucose: 144 mg/dL
Creatinine: 1.2 mg/dL
Ca2+: 9.8 mg/dL
Which of the following is the most accurate test for this patient's condition?
- A. Colonoscopy
- B. Sigmoidoscopy
- C. Amylase and lipase levels
- D. Barium enema
- E. CT scan (Correct Answer)
Diagnostic approach to acute abdomen Explanation: ***CT scan***
- The patient presents with classic symptoms of **diverticulitis**, including **left lower quadrant pain**, **fever**, and **leukocytosis**. A **CT scan with oral and IV contrast** is the most accurate diagnostic test to identify diverticular inflammation, abscess formation, or perforation.
- A CT scan can also help rule out other causes of abdominal pain and guide further management, such as the need for percutaneous drainage of an abscess.
*Colonoscopy*
- **Colonoscopy is contraindicated during an acute episode of diverticulitis** due to the risk of **perforation** of an inflamed colon.
- It may be considered **6-8 weeks after resolution of acute diverticulitis** to investigate for other pathologies such as malignancy.
*Sigmoidoscopy*
- Similar to colonoscopy, **sigmoidoscopy is generally avoided in acute diverticulitis** because of the risk of **perforation** of the inflamed bowel from instrumentation.
- Its diagnostic yield in acute settings is also limited compared to CT imaging.
*Amylase and lipase levels*
- These tests are primarily used to diagnose **pancreatitis**, which typically presents with **epigastric pain radiating to the back**, often associated with elevated enzyme levels.
- While vomiting is present, the **left lower quadrant tenderness and fever** point away from pancreatitis as the primary diagnosis.
*Barium enema*
- **Barium enema is generally contraindicated in acute diverticulitis** due to the risk of **perforation** and the introduction of barium into the peritoneum, which can cause severe peritonitis.
- It has largely been replaced by **CT scanning** for its superior safety profile and diagnostic accuracy in acute abdominal conditions.
Diagnostic approach to acute abdomen US Medical PG Question 6: A 58-year-old man comes to the emergency department with complaints of abdominal pain, swelling, and fever for the last few days. Pain is situated in the right upper quadrant (RUQ) and is dull and aching. He scores it as 6/10 with no exacerbating or relieving factors. He also complains of anorexia for the same duration. The patient experiences a little discomfort while lying flat and has been sleeping in a recliner for the past 2 days. There has been no chest pain, nausea, vomiting, or change in bowel or bladder habit. He does not use tobacco, alcohol, or any recreational drug. He is suffering from polycythemia vera and undergoes therapeutic phlebotomy every 2 weeks, but he has missed several appointments. The patient’s mother died of a heart attack, and his father died from a stroke. Temperature is 38.2°C (100.8°F), blood pressure is 142/88 mm Hg, pulse is 106/min, respirations are 16/min, and BMI is 20 kg/m2. On physical examination, his heart and lungs appear normal. Abdominal exam reveals tenderness to palpation in the RUQ and shifting dullness.
Laboratory test
Hemoglobin 20.5 g/dL
Hematocrit 62%
WBC 16,000/mm3
Platelets 250,000/mm3
Albumin 3.8 g/dL
Diagnostic paracentesis
Albumin 2.2 g/dL
WBC 300/µL (reference range: < 500 leukocytes/µL)
What is the best next step in management of the patient?
- A. Venography
- B. MRI
- C. Ultrasound (Correct Answer)
- D. Liver biopsy
- E. Echocardiography
Diagnostic approach to acute abdomen Explanation: ***Ultrasound***
- The patient presents with **fever**, **RUQ pain**, and **ascites**, along with a history of **polycythemia vera** which increases the risk of **thrombosis**. These symptoms strongly suggest **Budd-Chiari syndrome**, a condition where there is **hepatic vein obstruction**.
- **Doppler ultrasound** is the **initial diagnostic test of choice** for suspected Budd-Chiari syndrome, as it is non-invasive and can visualize hepatic vein flow, identify clots, and detect ascites.
*Venography*
- **Hepatic venography** is considered the **gold standard** for diagnosing Budd-Chiari syndrome but is **invasive** and typically performed only if Doppler ultrasound is inconclusive or if interventional procedures are planned.
- It would not be the best **next step** given the availability of less invasive imaging options for initial assessment.
*MRI*
- **MRI** with MR venography can provide detailed visualization of hepatic veins and parenchyma, and is useful if ultrasound is inconclusive.
- However, similar to venography, it is **not typically the first-line imaging modality** due to its higher cost and longer acquisition time compared to ultrasound.
*Liver biopsy*
- A **liver biopsy** can confirm liver damage and identify the cause of liver disease, but it is **invasive** and associated with risks like bleeding.
- It is usually reserved for cases where other diagnostic methods have not provided a clear diagnosis, and it would not be the initial diagnostic step for suspected vascular obstruction.
*Echocardiography*
- **Echocardiography** evaluates the heart's structure and function. While important for assessing cardiac causes of abdominal symptoms (e.g., right-sided heart failure causing liver congestion), it would not directly diagnose hepatic vein obstruction.
- The patient's symptoms are localized to the abdomen with **RUQ pain** and signs of **ascites**, making a primary cardiac issue less likely as the initial diagnostic focus.
Diagnostic approach to acute abdomen US Medical PG Question 7: A 42-year-old man presents to the emergency department with abdominal pain. The patient was at home watching television when he experienced sudden and severe abdominal pain that prompted him to instantly call emergency medical services. The patient has a past medical history of obesity, smoking, alcoholism, hypertension, and osteoarthritis. His current medications include lisinopril and ibuprofen. His temperature is 98.5°F (36.9°C), blood pressure is 120/97 mmHg, pulse is 130/min, respirations are 22/min, and oxygen saturation is 97% on room air. The patient is in an antalgic position on the stretcher. His abdomen is rigid and demonstrates rebound tenderness and hypoactive bowel sounds. What is the next best step in management?
- A. CT of the abdomen
- B. Urgent laparoscopy
- C. NPO, IV fluids, and analgesics
- D. Urgent laparotomy (Correct Answer)
- E. Abdominal radiograph
Diagnostic approach to acute abdomen Explanation: ***Urgent laparotomy***
- The patient's presentation with **sudden, severe abdominal pain**, a **rigid abdomen**, **rebound tenderness**, and **hypoactive bowel sounds** indicates **acute peritonitis**, most likely from a **perforated viscus**.
- In a patient with **frank peritonitis** and clinical signs of perforation, the diagnosis is **made clinically** based on physical examination findings.
- **Urgent laparotomy** (exploratory surgery) is the definitive management and should not be delayed for imaging when peritonitis is obvious.
- The patient's risk factors (NSAID use, alcoholism) further support peptic ulcer perforation as the likely etiology.
*CT of the abdomen*
- While CT scan is highly sensitive for identifying perforation and can provide anatomic detail, it is **not necessary when the diagnosis of peritonitis is clinically evident**.
- In a patient with **obvious peritonitis**, obtaining a CT scan would **delay definitive surgical treatment** without changing management.
- CT is more appropriate for stable patients with **uncertain diagnosis** or equivocal physical findings, not for those with frank peritonitis.
*Urgent laparoscopy*
- **Laparoscopy** can be used diagnostically and therapeutically in selected cases of abdominal emergencies.
- However, in a patient with diffuse peritonitis and suspected perforation, **laparotomy** is generally preferred over laparoscopy as it provides better exposure, faster source control, and easier peritoneal lavage.
- Laparoscopy may be considered in stable patients with localized findings, but this patient has signs of diffuse peritonitis.
*NPO, IV fluids, and analgesics*
- These are **essential supportive measures** and should be initiated immediately as part of resuscitation.
- However, they are **adjunctive** to definitive surgical management and do not constitute the "next best step" in a patient requiring emergency surgery.
- These measures should be initiated concurrently while preparing for urgent laparotomy.
*Abdominal radiograph*
- An **upright chest X-ray** or **abdominal radiograph** can show **free air under the diaphragm** (pneumoperitoneum) in cases of perforation.
- However, it is **only 50-70% sensitive**, meaning it misses many perforations.
- In a patient with **clinical peritonitis**, the absence of free air on X-ray does **not rule out perforation** and should not delay surgery.
- Imaging should not delay surgical intervention when peritonitis is clinically evident.
Diagnostic approach to acute abdomen US Medical PG Question 8: A 57-year-old man is admitted to the ER due to an abrupt onset of abdominal pain that radiates to the back, nausea, and multiple vomiting episodes for the past 10 hours. He does not have any significant past medical history. He admits to drinking alcohol every night. During admission, he is found to have a body temperature of 37.5°C (99.5°F), a respiratory rate of 20/min, a pulse of 120/min, and a blood pressure of 120/76 mm Hg. He looks pale with sunken eyes and has significant epigastric tenderness and flank discoloration. An initial laboratory panel shows the following:
Total count (WBC) 10,000/mm3
Platelet count 140,000/mm3
Serum glucose 160 mg/dL
Serum LDH 500 IU/L
Aspartate aminotransferase 400 IU/dL
Serum Amylase 500 IU/L
Serum Lipase 300 IU/L
Which of the following combinations would best predict severity in this case?
- A. WBC, platelet count, AST
- B. Age, glucose, amylase
- C. Age, LDH, AST (Correct Answer)
- D. Glucose, LDH, AST
- E. AST, amylase, lipase
Diagnostic approach to acute abdomen Explanation: ***Age, LDH, AST***
- The **Ranson's criteria** for predicting the severity of acute pancreatitis on admission include **age greater than 55 years**, **LDH greater than 350 IU/L**, and **AST greater than 250 IU/L**.
- In this patient, his age is 57 years, LDH is 500 IU/L, and AST is 400 IU/L, all of which align with poor prognostic indicators according to Ranson's criteria.
*WBC, platelet count, AST*
- While **WBC count** is part of Ranson's criteria (greater than 16,000/mm3 is a poor prognostic sign), the patient's WBC is 10,000/mm3, which is not elevated enough to indicate severe pancreatitis.
- **Platelet count** is not typically used as an acute prognostic indicator in Ranson's criteria for pancreatitis severity.
*Age, glucose, amylase*
- **Age greater than 55 years** and **glucose greater than 200 mg/dL** are initial Ranson's criteria for severity. However, the patient's glucose is 160mg/dL, which is not above the specified cutoff.
- **Amylase** and **lipase** are diagnostic for pancreatitis but are not used as prognostic indicators within Ranson’s criteria to predict severity.
*Glucose, LDH, AST*
- **Glucose greater than 200 mg/dL**, **LDH greater than 350 IU/L**, and **AST greater than 250 IU/L** are all included in Ranson's criteria. However, because the patient’s glucose level (160 mg/dL) is below the cutoff of 200 mg/dL, this combination is not the **best** predictor of severity in this specific case.
- The age of the patient is also an important factor in Ranson's criteria and is missing from this option.
*AST, amylase, lipase*
- While **AST greater than 250 IU/L** is a Ranson's criterion for severity, **amylase** and **lipase** levels, though elevated and diagnostic, are not used as prognostic indicators in Ranson's criteria for predicting the severity of acute pancreatitis.
- Amylase and lipase levels often do not correlate with the severity of the disease.
Diagnostic approach to acute abdomen US Medical PG Question 9: A 55-year-old man presents to the emergency department with nausea and vomiting. The patient states that he has felt nauseous for the past week and began vomiting last night. He thought his symptoms would resolve but decided to come in when his symptoms worsened. He feels that his symptoms are exacerbated with large fatty meals and when he drinks alcohol. His wife recently returned from a cruise with symptoms of vomiting and diarrhea. The patient has a past medical history of poorly managed diabetes, constipation, anxiety, dyslipidemia, and hypertension. His temperature is 99.5°F (37.5°C), blood pressure is 197/128 mmHg, pulse is 100/min, respirations are 17/min, and oxygen saturation is 95% on room air. Physical exam reveals a systolic murmur heard loudest along the left upper sternal border. Abdominal exam reveals an obese, tympanitic and distended abdomen with a 3 cm scar in the right lower quadrant. Vascular exam reveals weak pulses in the lower extremities. Which of the following is the most likely diagnosis?
- A. Enteric nervous system damage
- B. Twisting of the bowel
- C. Adhesions (Correct Answer)
- D. Norovirus
- E. Impacted stool
Diagnostic approach to acute abdomen Explanation: ***Adhesions***
- The patient's history of a 3 cm scar in the right lower quadrant suggests a prior abdominal surgery, which is the most common cause of **intra-abdominal adhesions**.
- **Adhesions** can lead to **small bowel obstruction**, causing symptoms like nausea, vomiting, abdominal distension, and tympany, which are all present in this patient.
*Enteric nervous system damage*
- Poorly managed diabetes can cause **diabetic gastroparesis**, which involves damage to the **enteric nervous system** leading to delayed gastric emptying.
- While it can cause nausea and vomiting, it doesn't typically present with significant abdominal distension or tympany, which are indicative of a mechanical obstruction.
*Twisting of the bowel*
- **Volvulus**, or twisting of the bowel, causes acute abdominal pain, distension, and often complete obstruction.
- While it's a possibility for bowel obstruction, the presence of a surgical scar and gradual worsening of symptoms over a week makes **adhesions** a more likely cause in this scenario.
*Norovirus*
- **Norovirus** is a common cause of acute gastroenteritis, characterized by abrupt onset of vomiting and diarrhea, often with a rapid resolution.
- Although his wife has similar symptoms, the patient's symptoms have been ongoing for a week, are exacerbated by fatty meals, and include abdominal distension, which is inconsistent with typical norovirus infection.
*Impacted stool*
- **Fecal impaction** can cause constipation, abdominal pain, and sometimes paradoxical diarrhea.
- While the patient has a history of constipation, the significant **tympanic distension** and persistent vomiting suggest a mechanical obstruction rather than just impacted stool.
Diagnostic approach to acute abdomen US Medical PG Question 10: 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
Diagnostic approach to acute abdomen 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.
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