Blogs to Boards: Question 10

Mr. G. Da Salva is a 68 year old construction worker who has metastatic non-small cell lung cancer involving his right femur and pelvis. Medications include: Morphine ER 200mg bid, Morphine IR 30-60mg PO q2 hours prn, and dexamethasone 8mg daily. At rest his pain is well managed, 2/10. However, he fears movement due to severe pain and spends most of the day in his recliner, avoiding showering or changing or helping with the meals. He uses approximately 5 doses daily of 60mg short-acting morphine for this pain but once it starts to work the pain has often spontaneously subsided and he becomes sleepy and confused.

Which of the following is LEAST appropriate?

  1. Take a short-acting morphine prior to a clustering his activities: showering, changing, fixing a meal.
  2. Add sublingual fentanyl 200mcg to take prior to his activities.
  3. Increase his long-acting morphine to 200mg tid.
  4. Single-fraction radiation therapy to his pelvis and femur.
  5. Intrathecal pump with morphine and low-dose bupivacaine.

Discussion: Correct answer is (c)

This is an example of incidental pain. It differs from breakthrough pain in that it is associated with movement, and diminishes as soon as the activity ends. The challenge with this form of pain management is that the pharmacology of systemic opioids does not tend to match the timing of this type of pain.

  1. Clustering his activities together so that they all take longer may better match the t1/2 of the short-acting morphine, but he will still need to take the medicine approximately 40 minutes prior to starting the activities.
  2. Sublingual or buccal fentanyl has a shorter half-life and shorter time to onset than other oral opioids and is a better option.
  3. Is the correct answer: Increasing the long-acting morphine is the least appropriate because this will not help the incidental pain and may worsen his confusion when he is not moving around.
  4. Single fraction radiation therapy would be very appropriate in this setting and would likely be one of the most preferred interventions as long as he had not previously been irradiated at the site of pain.
  5. Intrathecal pain medication delivery is another good option. However, this is an expensive procedure and requires a prognosis of at least 3 months to assure coverage by insurance plans. Because the dose of opioid is a fraction of systemic opioid delivery, its risk of side-effects is lower and is a more effective means of managing incidental pain in the lower back and lower extremities.

References:

  • http://www.aahpm.org/apps/blog/?p=809
  • http://www.pallimed.org/2009/12/poll-results-palliative-care-experience.html
  • Bruera, E., & Kim, H. N. (2003). Cancer pain. JAMA : the journal of the American Medical Association, 290(18), 2476-9.
  • Chow, E., Harris, K., Fan, G., Tsao, M., & Sze, W. M. (2007). Palliative radiotherapy trials for bone metastases: a systematic review. Journal of clinical oncology : official journal of the American Society of Clinical Oncology, 25(11), 1423-36.
  • Smith, T. J., Swainey, C., & Coyne, P. J. (2005). Pain management, including intrathecal pumps. Current Pain and Headache Reports, 9(4), 243-248. Current Medicine Group LLC.