Post-operative ileum

Question 1

A 55 year old woman had has severe constipation five days after her abdominal hysterectomy. How would you assess and manage her?

Answer 1

Impression
In this case of post-operative constipation, there are a number of potential causes to consider in this patient, both mechanical and non-mechanical.

DDx
- Paralytic Ileus (peak occurrence at 2-3 days post-op)
- pseudo-obstruction (megacolon
- medications (anaesthetic)
- SBO/LBO (mechanical obstruction)

Goals
- thorough Hx/Ex/Ix, rule out HD instability. Treatment is aetiology dependent

Question 2

Post-op constipation - History

Answer 2

History
- sx: distension, bloating, N/V - colour of vomit? bilious vs faecalant. constipation/obstipation, Pain (SOCRATES, colicky vs constant)
- Features of peritonism/severe: fever, lethargy/fatigue, confusion, haematochezia, malaena
- Review op report notes, medical management, any relevant nursing obs, fluid balance chart.

Question 3

Post-op constipation - Examination

Answer 3

Examination
- Vitals: should be HD stable in ileus
- hydration status assessment
- Abdo exam: distension, tenderness, look for wound infection, signs of peritonism, evidence of hernias, assess any intra-abdominal drains
- PR exam: masses and blood

Question 4

Post-op constipation - Investigations

Answer 4

Investigations
- bedside: VBG (lactic acidosis), ECG
- bloods: FBC, G+H if back for theatres, coags, UEC/LFT, blood cultures if septic, lipase
- imaging: upright AXR for air under diaphragm (perf), look for dilated loops of bowel in SBO/LBO/megacolon, Abdo CT with IV contrast +/- oral contrast

Question 5

Post-op constipation - Management

Answer 5

Management
- call for surgical consult and review, notify the gen surg reg on call.
- initiate supportive treatment of symptoms

Supportive
- antiemetics, analgesia (avoid opioids as increase risk of ileus), antipyretics (if fevers)
- NBM for bowel rest
- PPI as there is a risk of developing ulcers if NBM
- regular obs
- fluids + electrolytes, consider TPN if likely ongoing NBM
- NGT for gastric decompression, to prevent the risk of aspiration pneumonia particularly if N/V sx. initially aspirate, then on free drainage + 4-hourly aspirates.
- medications review

Definitive
- address reversible factors: medications, inflammation, infection, metabolic (electrolyte derangements)
- Aperients (osmotic, stimulant, fibre supplement)
- Gastrografin challenge for SBO
- theatres for LBO
- flexible sigmoidoscopy for LBO in select cases (sigmoid volvulus, decompression of megacolon
- IV antibiotics for any complicated infection (sepsis, toxic megacolon, etc)