Malignant Bowel Obstruction

•    Causes:

o    Common in advanced intra-abdominal malignancies 

                                    (e.g., ovarian, gastric, colorectal, pancreatic cancers).

o    Mechanical obstruction from tumour mass, peritoneal carcinomatosis, or extrinsic compression.

•    Clinical features:

o    Nausea and vomiting (may be feculent if distal).

o    Colicky abdominal pain.

o    Distension.

o    Absolute constipation (no flatus or stool).

•    Management:

o    Medical approach preferred in advanced disease:

    Steroids (e.g., dexamethasone 8–16 mg/day): reduce peritumoural oedema, may help lumen patency.

    Antiemetics:

    Cyclizine (vestibular/central antiemetic) — often first choice.

    Haloperidol for chemical causes.

    Octreotide (somatostatin analogue):

    Reduces GI secretions and motility.

    Dose: 300–600 micrograms SC/24 h.

o    Analgesia:

    Opioids for pain control (usually continuous SC infusion).

o    Fluids:

    Avoid aggressive IV fluids unless specific indication (may worsen vomiting).

o    Surgery:

    Only considered in highly selected cases (fit patients, isolated obstruction amenable to bypass).

Massive Haemorrhage ("Catastrophic Bleed")

•    Common causes:

o    Erosion of tumour into major vessels (e.g., head and neck cancers, advanced GI cancers).

o    Local ulceration.

•    Clinical features:

o    Sudden, large-volume bleeding (e.g., haematemesis, epistaxis, external bleeding).

o    Rapid deterioration → imminent death.

•    Management priorities:

o    Sedation:

    Midazolam (e.g., 5–10 mg SC or IV bolus) to reduce awareness and distress.

o    Environmental measures:

    Use dark towels (minimise visible blood for family).

    Calm, quiet surroundings.

o    Focus on dignity and comfort rather than invasive resuscitation.

•    Family support:

o    Provide anticipatory guidance if high risk identified.

o    Reassure that patient is unlikely to be aware or distressed during catastrophic bleed.

Extra Revision Pearls

•    Malignant obstruction: if high small bowel obstruction → may see large volume vomit; if low, distension is more prominent.

•    Octreotide: useful even if obstruction is partial — reduces secretions, improves symptom burden.

•    Haemorrhage packs: prepare anticipatory medications and dark towels in high-risk patients.

•    Avoid futile interventions: focus is on symptom control, not on prolonging life in these emergencies.

•    Anticipatory prescribing: essential in community palliative care — ensures rapid access to sedation if needed.