Malignant Bowel Obstruction When Surgery Is Not an Option
Ms. L is a 61-year-old woman with recurrent ovarian cancer, peritoneal carcinomatosis, prior debulking, and two lines of chemotherapy. Over three days she has vomited 8–10 times daily, has colicky periumbilical pain every few minutes, and has passed no flatus or stool. Her abdomen is distended and tympanitic without peritoneal signs. CT shows multiple small-bowel transition points from carcinomatosis, no discrete mass, and no free air. The surgical consultant says neither adhesiolysis nor stenting is appropriate. Ms. L is alert and asks, 'Can't you just fix the blockage so I can go home?' She has a PICC, a creatinine of 1.4 mg/dL, and lives with her sister.
1. Design a subcutaneous medication regimen for her obstruction, giving doses and explaining why prokinetics are avoided.
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Her vomiting makes oral absorption unreliable, so use the subcutaneous route, ideally via a continuous infusion pump to support going home.
- Octreotide 100–200 mcg subcutaneously every 8 hours, titratable to 300–600 mcg/day. It decreases splanchnic secretion and gut-wall tension, reducing both vomiting and colic.
- Dexamethasone 4–8 mg subcutaneously or intravenously daily. It reduces peritumoral edema and may partially relieve obstruction over 3–5 days.
- Haloperidol 0.5–2 mg subcutaneously every 6–8 hours for nausea, an alternative to metoclopramide when obstruction is complete.
- Opioid for colic: hydromorphone 0.5–1 mg subcutaneously every 2–4 hours as needed, or a low continuous infusion once the requirement is known.
- Glycopyrrolate 0.2 mg subcutaneously every 6 hours if secretions or vomiting persist.
Metoclopramide is a prokinetic and is contraindicated in complete obstruction: it raises intraluminal pressure, worsens colic, and risks perforation. Reserve it for incomplete obstruction without colic. Avoid oral medications and review renal dosing of any renally cleared drugs.
2. How would you answer her question about 'fixing' the blockage, and how do you decide about hydration?
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Answer honestly while preserving agency and hope. Say something like: 'I can't promise surgery will open this. In about one in four people with this kind of blockage, medicines alone quiet the vomiting and pain within a few days. What I can promise is that we will work hard to control the symptoms and, if you want, get you home with hospice support.' Avoid 'there is nothing more to do,' which is both untrue and heard as abandonment.
Set a time-limited trial: reassess in 48–72 hours and decide together whether to continue, add an NG tube, or shift fully to comfort care.
Hydration: 500–1,000 mL/day subcutaneously or intravenously may ease thirst and colic, but it can also increase gut secretions and vomiting. There is no survival benefit from large-volume fluids in this setting. Offer ice chips, frequent mouth care, and small sips, and document the reasoning and her preference. Ask about home hospice now, because discharge planning takes time and the subcutaneous pump makes home care feasible.
3. Vomiting persists after 72 hours of octreotide and dexamethasone. What are the next options, and how do you weigh them?
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First, check for reversible contributors: fecal impaction, hypercalcemia, new medications, urinary retention, and whether the octreotide and dexamethasone doses are adequate. Then weigh options against prognosis, setting, and her goals.
- Escalate octreotide to 300–600 mcg/day and add an anticholinergic such as glycopyrrolate or scopolamine.
- Nasogastric decompression can relieve intractable vomiting within hours, but it is uncomfortable, may require ongoing suction, and often prevents home discharge; use it as a time-limited trial, not a default.
- Venting gastrostomy is effective for recurrent obstruction in patients with weeks to months of prognosis and can be done percutaneously, but requires expertise and a procedure.
- If she is actively dying and vomiting remains intractable, low-dose midazolam or levomepromazine-type sedation may be appropriate, with consent and after clarifying goals.
The decision hinges on prognosis, her stated wish to be home, and caregiver capacity. Present two or three concrete options with burdens and benefits, recommend one, and document the conversation.