1. Palliative Care of Malignant Bowel Obstruction

2. The presenter has no financial, or other disclosures to provide

3. Objectives
Recognize medical palliative measures and the importance of implementation regardless of approach to treatment.
Identify role of endoscopic treatment
Identify who benefits from surgical intervention

4. Malignant Bowel Obstruction (MBO)
Occurs predominantly in advanced disease stage
Median survival after onset days
Incidence:
5-51% ovarian cancer
10-28% GI cancer

5. Non pharmacological symptom management
IV hydration (ensure adequacy based on GI output)
Electrolyte replacement
Environmental controls
Decompression
NG tube: acceptable for short term management only
Often occlude
Multiple complications
associated with physical, social and psychological discomfort
Percutaneous gastrostomy tube preferred when symptoms not able to be controlled with medical or surgical management

6. Pharmacological management: Pain
Should always be controlled, regardless….
Will require opioids, use standard dosing and titration
Opioids can aggravate colic by stimulating circular smooth muscle leading to subsegmental contractions
Opioid sparing adjuvant drugs should be maximized.
Ketorolac may improve colic and pain as well as prevent partial obstruction converting to full.
Opioid induced colic can be reduced with anti secretory medications (robinul, scopolamine, sandostantin), which are usually required anyway.

7. Control of nausea and vomiting requires consideration of pathology
Peripheral considerations: Stretch receptors leading to hyperperistalsis and hypersecretion
Chemoreceptor trigger zone activation via toxins, drugs, and metabolic derangements
Cortex involvement: anxiety, anticipatory nausea and vomiting, triggering through senses
Vestibular: less likely etiology in MBO, but may be a factor if dehydrated

8. Pharmacological interventions to block CRTZ: Ondansetron
More effective for chemotherapy and radiation therapy induced nausea and vomiting
Considered to have fewer side effects than other medications that interact with CRTZ; however, constipation, and QT prolongation are known side effects and should be considered
More expensive than others with similar mechanism
Dose: 4mg PO/Iv q4-6h or 8mg PO/IV tid

9. Pharmacological intervention for blocking the CRTZ: Haldol
Considered the most effective for management of nausea and vomiting in MBO
Dosing: 0.5-2mg PO/IV/SQ q6h, then titrate
Side effects: Drowsiness and extrapyramidal symptoms (if necessary can be offset by low dose Cogentin)

10. Pharmacological intervention: metoclopramide
Generally avoided due to prokinetic effects which increases colic pain and secretions
Should only be used in partial obstructions

11. Management of peripheral etiologies
Decompression is essential not only for pain but for nausea and vomiting
Anti secretory agents: Decrease distension and pain as well as nausea and vomiting by decreasing peristalsis as well as secretions
Somatostatin analogue: Effects same as anti secretory agents with additional decreased gastric acid, bile flow and splanchnic blood flow and increases absorption of water and electrolytes

12. Scopolamine Dosing: Side effects: Dry mouth, cognitive, visual
O.1-0.4mg SC q6h
mg/h infusion
Q72h patch
Side effects: Dry mouth, cognitive, visual

13. Glycopyrolate Dosing: Side effects: 0.2-.04mg SQ or IV q6h prn
0.02mg/h infusion
Side effects:
Similar to Scopolamine; however, due to being less lipid solubility has significantly lower impact on CNS side effects

14. Octreotide: mechanism related to decreasing GI hormones
Dosing:
50-100mcg SQ q8h
30mg Sandostatin LAR IM Q month
Side effects: dry mouth, increased thirst, constipation

15. Octreotide/Sandostatin
Have been shown to be more effective and faster than scopolamine in decreasing GI secretions in patient with NG tube.
Decreases intensity and frequency of nausea and emesis
May prevent irreversible bowl obstruction in patients with recurrent obstruction

16. Pharmacological interventions: Corticosteroids
In tumor related obstructions are believed to decrease peri luminal inflammatory edema, increase intestinal mobility as well as decrease nausea.

17. Gastric outlet obstruction: endoscopic scope placement vs Gastrojejunostomy
Endoscopy with stenting: In appropriate patients has increased success rate over gastrojejunostomy:
Shorter time to oral intake
Lower morbidity
Lower rate of delayed gastric emptying
Shorter length of stay

18. Gastric outlet obstruction: endoscopy vs gastrostomy tube
Gastrostomy tube indicated over endoscopy:
Life expectancy less than 1 month
Rapidly progressing disease
Ascites
Carcinomatosis
Multiple obstruction sites

19. Endoscopy with stent : Benefit
Used as a bridge to surgery, or for symptom relief if not surgical candidate
Allows time to mitigate co morbidities, enhance nutrition, and complete staging

20. Endoscopy with stent: Contraindications
Perforation with peritonitis
Rectal tumor within 2cm of anal margin (associated with tenesmus and fecal incontinence)

21. Endoscopy with stent: Complications
Migration:
Incidence 10%
Usually asymptomatic but ½ need repeat intervention
Bleeding 5%
Perforation:
Incidence 4%
Incidence 10% when dilatation performed with stent placement
Recurrent obstruction rate 10%

22. Considerations for determining if surgical intervention is appropriate:
Surgery provides a 10 fold or greater chance of 30 day survival in large bowel obstruction
Surgery generally considered contraindicated in patients with 30 day or less prognosis
Not all who have a better than 30 day prognosis benefit from surgical intervention

23. Short term prognosis scoring system:
Radiographic evidence of carcinomatosis point
Radiographic evidence of ascites point
Complete small bowel obstruction point
Hypoalbuminemia point
Leukocytosis point
Score of greater than 4 associated with 30 day survival of less than 60%

24. Nomogram to determine if surgery will provide benefit in SBO
Radiographic evidence of carcinomatosis point
Leukocytosis point
Hypoalbuminemia point
Non- gynecological cancer point
0-1 point surgery recommended
2 points surgical and non surgical approaches have equal outcomes
3-4 points risks and Burdon outweigh surgical benefit

25. Summary:
All patients should receive aggressive pharmacological symptom management which usually requires multiple medications
Endoscopy with stent placement has few contraindications and low complication rate and should be considered as a bridge to surgery or for symptom management in patients who are not surgical candidates
Three considerations when deciding if surgery is appropriate
LBO vs SBO
Short term prognosis
Apply nomogram to determine if patient will receive benefit from surgical intervention

26. Resources and References
S. Soriano, MD, D. Mellar, MD. Malignant Bowel Obstrution: Indiidualized treatment near the end of life. Cleveland Clinic Juournal of Medicine. Volume 78. March 2011.
J. henry, MD et al. A scoring system for the prognosis and treatment of malignant bowel obstruction. Surgery October: 153(4): doi: /j.surg
EPEC: Education in Palliative and end of life care Modules: Bowel obstruction, and Nausea and vomiting.