Presenting Complaint:

Severe, sudden-onset upper abdominal pain, associated with nausea and vomiting.

“It felt like someone stabbed me in the belly, out of nowhere. I’ve never had anything like this before.”

Symptoms:

• Site: Epigastric initially
  “Right in the top middle of my belly.”
  
• Onset: Sudden onset, around 6 hours prior to arrival in A&E.
  “It just came on out of the blue – sharp and intense, right under my ribs.”
  
• Character: Sharp, stabbing pain
  “Like a knife.”
  
• Radiation: Now generalised across entire abdomen
  “Now it feels like it’s everywhere.”
  
• Associated Symptoms: Nausea, vomited once, feeling bloated
  “I feel sick and bloated.”
  
• Timing: Continuous, no pain-free intervals
  “Hasn’t let up since it started.”
  
• Exacerbating/Relieving Factors: Worse on movement, slightly relieved by being still. Over-the-counter analgesia is completely ineffective.
  
• Severity: 9/10
  “Almost unbearable, one of the worst pains I’ve ever felt.”

Systemic Symptoms:

• Fatigue:
  “I’m wiped out – just exhausted.”
• Fever: Mild, feeling hot and flushed
  “Felt hot before coming in.”
• Night Sweats: None
  “No sweating at night.”
• Weight Loss: No recent unintentional weight loss
• Malaise:
  “I just feel unwell all over.”
• Bowel Habits: No bowel movement since yesterday morning
  “Nothing’s moved since yesterday.”
• Urinary Habits: Normal before this episode
• Gastrointestinal: No haematemesis, no melaena 
• Respiratory: No cough or dyspnoea
• Cardio: No chest pain, dizziness or palpitations
• Peripheral Oedema: None

Past Medical History:

• Hypertension (diagnosed 2010)
• H. pylori infection (treated in 2012)
• Right inguinal hernia repair (2015)

Drug History:

• Amlodipine 5mg once daily
• Ibuprofen as needed for occasional back pain, taken more regularly recently

Allergies:

• Penicillin – Causes urticaria and wheezing
  “I break out in hives and my chest tightens up if I take it.”

Social History:

• Occupation: Retired electrical engineer
• Living Situation: Widowed, lives alone in a ground-floor flat, iADLs
• Exercise: Walks to local shops, otherwise sedentary
• Smoking: Quit 20 years ago, previously 20 pack-years
• Alcohol: None
• Travel: No recent travel; last international trip was 2019

“I used to smoke, but I gave that up long ago. I don’t drink alcohol.”

Ideas, Concerns, and Expectations:

Ideas: “Maybe it’s just some bad food I ate… or gas? But it feels too strong for that.”

Concerns: “I’m worried something’s burst inside… I’ve never felt pain like this in my life.”

Expectations: “I want to know what’s going on quickly. Please check properly – scans, bloods, whatever you need.”

A-E Examination

Observations:

• Respirations: 24 breaths/min
• Oxygen Saturation: 95% on room air
• Air or Oxygen: Air
• Blood Pressure: 98/67 mmHg
• Pulse: 110 bpm
• Consciousness: Alert (A)
• Temperature: 38.1°C

NEWS Total Score: 7

General Inspection:

• Unwell, lying still, grimacing in pain

• Abdomen slightly distended

Airway:

• Patent, patient speaking

• Nil action required 

Breathing:

• Resp rate 24, SpO2 95% on room air

• Speaking full sentences, slightly tachypnoeic but not obviously short of breath

• No cyanosis

• Trachea central

• Percussion resonant bilaterally

• Chest clear

Investigations

• Erect CXR for subdiaphragmatic free air

• ABG for lactate

Interventions

• In line with CCRISP principles, provide high-flow oxygen during initial assessment/resuscitation

Circulation:

• Pulse 110 bpm, BP 98/67

• Slightly dry mucous membranes

• Cool peripheries

• CRT 4s

• Radial pulse fast and regular

• JVP not raised

• HS I+II+0

Investigations

• ECG – sinus tachycardia

• Blood tests – FBC, U&E, LFTs, CRP, lactate (if ABG/VBG not taken), clotting screen, 2x G&S +/- crossmatch

• VBG (if ABG not done)

• Blood cultures

Interventions

• IV access with two wide-bore cannulas – resuscitate with crystalloid bolus (e.g Plasmalyte, Hartmann’s, normal saline)

• Catheterise for fluid balance monitoring

• Commence intravenous antibiotics in line with local guidelines (note penicillin allergy)

• High dose IV PPI e.g. pantoprazole

Disability:

• Pupils 4mm PEARL

• Capillary glucose 5.6

• Alert, GCS 15/15

• Neurology grossly intact, moving all 4 limbs

• Severe pain

Interventions

• Strong analgesia e.g. oral or IV morphine + paracetamol

Exposure:

• Temperature 38.1

• Abdomen slightly distended

• Right inguinal hernia repair scar noted

• Diffuse severe tenderness all quadrants/regions, especially epigastric

• Guarding and rigidity present on palpation 

• Rebound and percussion tenderness positive

• Nil bowel sounds auscultated

• Nil abdominal masses palpated

• No peripheral oedema

• No rashes or wounds

Investigations

• Urine dipstick – negative

Interventions

• If profuse vomiting, consider Ryles tube insertion

Other (if asked for):

• Digital rectal examination: Empty rectum, no masses, no blood, no mucous

• Genitourinary: Normal external genitalia

Examiner Questions:

1. Please interpret the following investigations:

Case courtesy of Frank Gaillard, Radiopaedia.org, rID: 17957

Answer:

• ABG – Metabolic acidaemia with low bicarb and low base excess, raised lactate. GI perforation and intra-abdominal sepsis can cause metabolic acidosis.
• Bloods – Raised inflammatory markers (WBC, neutrophils, CRP). Evidence of some renal impairment could be resulting from developing intra-abdominal sepsis.
• CXR – subdiaphragmatic air under both diaphragmatic domes (yellow dotted line). Gas also seen in stomach (red dotted line) and splenic flexure of colon (blue dotted line). In keeping with pneumoperitoneum which is highly suggestive of perforation in this clinical presentation.

2. What is your working diagnosis and differential diagnoses and why?

• Gastrointestinal perforation (most likely diagnosis) – likely secondary to peptic ulcer given the clinical features, history and risk factors (previous H. pylori infection and NSAID use). Examination findings in keeping with perforation – severe tenderness, abdominal rigidity and guarding in addition to percussion and rebound tenderness. CXR shows subdiaphragmatic air indicative of GI perforation.
• Acute pancreatitis – less likely here given normal amylase however also presents with acute epigastric pain and vomiting. Free air on radiology suggests perforation.
• Small bowel obstruction +/- perforation – there are risk factors for adhesional SBO with previous surgery for hernia repair so this is a key differential. Vomiting (may be bilious) would typically be a more significant feature, with marked abdominal distension. Examination findings (rigidity, severe tenderness, guarding) in keeping with perforation.
• Acute diverticulitis – pain typically in the left lower quadrant, and history may include diverticular disease. Can perforate as well.
• Acute mesenteric ischaemia – presents with severe diffuse abdominal pain +/- bloody diarrhoea, and can cause perforation due to local ischaemia and necrosis of bowel. Key clues in history would be possible thromboembolic source (e.g. AF, cardiac mural thrombus, severe arterial disease). Lactate is typically high, in keeping with an ischaemic picture.

3. What are some of the causes of gastrointestinal perforation and what is the most likely site here given the risk factors and clinical features?

• Peptic ulcer disease, usually secondary to NSAID use or H. pylori infection – most likely here given the risk factors in the history and clinical features (severe epigastric pain).
• Perforated diverticulitis – pain typically localises to lower left quadrant, may be history of diverticular disease +/- constipation.
• Small bowel perforation secondary to small bowel obstruction (SBO) – this could be possible given the previous abdominal surgery which can cause adhesional SBO and lead to perforation. Bilious vomiting would typically be a feature (if the transition point is distal to the major papilla). SBO can also be cause by hernias and tumours.
• Large bowel perforation – can be secondary to malignancy, appendicitis, diverticulitis, severe colitis, volvulus and other causes of large bowel obstruction. History may include malignant B-symptoms or longer period of unopened bowels.
• Biliary perforation – can occur in severe cholecystitis or a complication of ERCP.
• Oesophagus – foreign body ingestion (batteries, caustic chemicals), severe vomiting (Boerhaave syndrome).

4. Following A-E resuscitation, what is your management plan? 

• Urgent surgical referral and review.
• Urgent CT abdomen if clinically stable to confirm diagnosis before surgery.
• Anaesthetic review.
• Will need consenting and booking in theatre for emergency laparotomy for washout and repair of perforation.