History Taking · Intermediate · Surgery

Severe Abdominal Pain with Vomiting and Distension

Practise this PLAB 2 history taking station on Intestinal Obstruction. 8-minute voice AI simulation with feedback on all 3 marking domains.

Clinical scenario

You are an FY2 doctor in the emergency department. Mrs Victoria Beck, a 68-year-old woman, has presented with severe colicky abdominal pain, repeated vomiting, and abdominal distension. She has not opened her bowels for three days. Please take a focused history and discuss your initial assessment and management plan.

Background notes: PMH: Type 2 diabetes, Hypertension, Previous abdominal surgery (hysterectomy 30 yrs ago), Diverticulosis

What this station tests

  • Classic obstruction tetrad: colicky pain, vomiting, distension, absolute constipation (no flatus is the key)
  • Adhesional small bowel obstruction as the most likely cause in a patient with previous abdominal surgery
  • Strangulation screening: continuous pain, fever, peritonism, elevated lactate indicating compromised blood supply
  • 'Drip and suck' management: IV fluids, NG tube, nil by mouth, catheter for monitoring
  • Conservative versus surgical decision: most adhesional SBO resolves conservatively, surgery if no improvement in 24-48 hours or if strangulated

How to use your 8 minutes

  • 0-1 min — Introduction: Introduce yourself, confirm identity, open question. 'What's brought you in today?'
  • 1-4 min — Systematic History: Presenting complaint detail (SOCRATES for pain, timeline, severity). Systems review. PMH, medications, allergies.
  • 4-6 min — Context and ICE: Social history (smoking, alcohol, occupation, living situation). Family history. Ideas, Concerns, Expectations.
  • 6-7 min — Summary and Plan: Summarise findings back to patient. Share differential/working diagnosis. Outline investigation and management plan.
  • 7-8 min — Closing: Safety netting with specific red flags. Arrange follow-up. Check for questions.

Consultation approach

The opening

Bowel obstruction presents with the classic tetrad: colicky abdominal pain, vomiting, distension, and absolute constipation. The candidate must assess for complications (strangulation, perforation) and initiate the 'drip and suck' management. Mrs Beck is 68, presenting with 18 hours of colicky pain, vomiting, distension, and no bowels or flatus for 3 days. Open with: 'Mrs Beck, you are clearly very unwell. I am going to start treating you while I take a quick history.'

Core approach

Confirm the obstruction pattern. Colicky pain (waves, cramping, 'twisting'): suggests mechanical obstruction. Vomiting (initially food, now bilious/greenish): suggests proximal obstruction. Abdominal distension (progressive). Absolute constipation (no faeces and no flatus for 36 hours): the absence of flatus is the key indicator of complete obstruction.

Identify the likely cause. She had a hysterectomy 30 years ago. Adhesional small bowel obstruction is the most likely diagnosis (adhesions from previous surgery are the commonest cause of SBO in developed countries). She also has known diverticulosis (less likely cause but possible). Ask about previous similar episodes (adhesional obstruction can be recurrent).

Screen for strangulation (surgical emergency). Continuous rather than colicky pain (suggests ischaemia). Fever. Tachycardia with peritonism. Localised tenderness with guarding. Elevated lactate. These features indicate compromised blood supply and need emergency surgery. Currently she has colicky pain without peritonism, suggesting simple obstruction.

ICE: She wonders if previous operations caused this (correct). She is terrified of cancer (her concern) and emergency surgery (at her age with diabetes).

Closing and safety netting

Immediate management: 'drip and suck.' IV fluids for rehydration (she has been vomiting for 18 hours and is dehydrated). NG tube for gastric decompression (relieves vomiting and distension). Nil by mouth. Catheter for urine output monitoring. Bloods: FBC, U&E, amylase, lactate, group and save.

Imaging: abdominal X-ray (air-fluid levels, dilated loops) and CT abdomen (to confirm level and cause of obstruction and exclude strangulation). Surgical review: all bowel obstructions need surgical assessment even if initially managed conservatively.

Many adhesional SBOs resolve with conservative management (drip and suck). Surgery is needed if no improvement in 24 to 48 hours, or immediately if strangulation is suspected. Address her cancer fear: 'The most likely cause given your previous surgery is scar tissue from the operation, not cancer. The CT scan will clarify this.' Safety net: she is admitted with surgical team oversight.

How examiners mark this station

Examiners will focus on the thoroughness and structure of your history taking for intestinal obstruction. Domain 1 (Data Gathering) carries the most weight: expect marks for systematic coverage of presenting complaint, red flags, PMH, medications, social and family history. Domain 2 (Clinical Management) requires a clear differential, appropriate investigations, and a safe management plan with safety netting. Domain 3 (Interpersonal Skills) is assessed throughout: genuine exploration of ICE, active listening, empathic responses, and clear communication without jargon.

Domain 1: Data Gathering, Technical and Assessment Skills (Primary focus)

Scores well: Obstruction tetrad confirmed. Surgical history obtained (hysterectomy 30 years ago). Strangulation screened (pain character, peritonism, fever). Dehydration assessed. Duration of absolute constipation quantified.

Costs marks: Not confirming the tetrad. Missing surgical history. Not screening for strangulation. Not assessing dehydration.

Domain 2: Clinical Management Skills (Primary focus)

Scores well: Drip and suck (IV fluids, NG tube, nil by mouth, catheter). Appropriate investigations (AXR, CT, bloods including lactate). Surgical review arranged. Conservative versus surgical pathway understood. Cancer concern addressed.

Costs marks: No NG tube. No CT. No surgical review. Not understanding conservative vs surgical management.

Domain 3: Interpersonal Skills (Throughout)

Scores well: Addressing cancer fear (adhesions most likely from previous surgery). Acknowledging her fear of emergency surgery. Explaining the conservative approach first. Honest about the possibility of surgery if needed.

Costs marks: Not addressing cancer concern. Being alarmist about surgery. Not explaining the management plan.

Common examiner feedback (and how to fix it)

Did not gather sufficient information to make an adequate assessment of the patient's condition

Fix: Use a consistent framework for every history. After covering the presenting complaint, systematically move through PMH, drug history, social history, family history, and ICE. Keep a mental checklist.

Did not identify the patient's problems and/or did not develop a management plan adequately

Fix: Reserve the final 2 minutes to summarise your findings, share your working diagnosis with the patient, and outline your investigation and management plan including safety netting.

Common mistakes in this station

  1. Not asking about previous abdominal surgery. Adhesions from previous surgery are the commonest cause of SBO. Candidates who do not take a surgical history miss the most likely aetiology.
  2. Not screening for strangulation. Simple obstruction can be managed conservatively. Strangulated obstruction needs emergency surgery. Candidates who do not check for continuous pain, fever, and peritonism cannot make this critical distinction.
  3. Not inserting an NG tube. Gastric decompression is a core part of obstruction management. Candidates who prescribe IV fluids and nil by mouth but do not mention NG tube provide incomplete management.

Resitting PLAB 2?

If you have previously struggled with history taking stations, focus on building a consistent systematic framework that you apply to every case. Practise structuring your history into clear phases (presenting complaint, systems review, PMH, social, ICE) so that even under pressure, you cover all domains. Many resitters lose marks not on knowledge but on organisation and time management.

Example opening

Good morning/afternoon, my name is Dr [Name], I'm one of the doctors here today. Could I confirm your name and date of birth please? Thank you. So, what's brought you in to see me today?

Frequently asked questions

How should I structure the intestinal obstruction history in this PLAB 2 station?

Bowel obstruction presents with the classic tetrad: colicky abdominal pain, vomiting, distension, and absolute constipation. The candidate must assess for complications (strangulation, perforation) and initiate the 'drip and suck' management. Mrs Beck is 68, presenting with 18 hours of colicky pain, vomiting, distension, and no bowels or flatus for 3 days.

What are examiners marking in this intestinal obstruction station?

Marks are won for: Obstruction tetrad confirmed. Surgical history obtained (hysterectomy 30 years ago). Strangulation screened (pain character, peritonism, fever). Dehydration assessed. Marks are lost for: Not confirming the tetrad. Missing surgical history. Not screening for strangulation. Not assessing dehydration.

What is the most common mistake candidates make in this intestinal obstruction station?

Not asking about previous abdominal surgery. Adhesions from previous surgery are the commonest cause of SBO. Candidates who do not take a surgical history miss the most likely aetiology.

How do I prepare for this station if I have not managed intestinal obstruction in clinical practice?

Structure beats experience here. Focus on adhesional small bowel obstruction as the most likely cause in a patient with previous abdominal surgery. Work through the consultation approach above, then rehearse it aloud under the 8-minute time pressure so the structure holds up in the exam.

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