Response to “Spinal analgesia: where is the evidence?”

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Transcript of Response to “Spinal analgesia: where is the evidence?”

LETTER TO THE EDITOR

Response to “Spinal analgesia: where is the evidence?”

Jeff Myers

Received: 22 July 2010 /Accepted: 23 July 2010 /Published online: 3 August 2010# Springer-Verlag 2010

Dear Editor,In response to our systematic review [1] addressing intra-spinal analgesia in the setting of cancer pain management,Drs. Bruera and Hui expressed concern regarding ourconclusion that “in general, the evidence supports” theavailability and use of this technique for appropriatelyselected patients. They are in agreement with the acknowl-edged methodologic concerns of three particular random-ized controlled trials (RCTs) and appropriately underscorethe limitations and potential bias associated with open labeland industry-sponsored studies. Of note, Drs. Bruera andHui question the clinical value of the Smith et al. study [2].We would offer that although the reported statisticalsignificance regarding efficacy was indeed borderline(p=0.055), the key strengths of this study include boththe comparatively large study population and the clearquality of life benefit (i.e., less toxicities) for patients withintraspinally delivered opioid. Drs. Bruera and Hui suggestour review addresses only opioids and neglect to acknowl-edge the multiple RCTs exploring the role for non-opioidintraspinal analgesics. We agree that further evidence isnecessary to clarify the specific role for intraspinal opioids,and acknowledge in our discussion the need for adequatelypowered and “well-designed randomized trials”. Further-more, we state unequivocally that adequate accrual “willrequire both a firm commitment from investigators andensuring adequate funding.” The point Drs. Bruera and Huimake in identifying the potential bias of industry-sponsoredtrials is well taken and agree the acknowledged funding

source would ideally be granting agencies and non-industrysponsors.

With respect to Drs. Bruera's and Hui's appropriateconcerns regarding technical complexity, procedural risksand catheter/pump-related complications, we believe theseelements are more than adequately summarized in bothsections “Indications for use” and “Implementation issuesfor safe delivery of intraspinal analgesia” of the review.Concerning these issues, we concluded however that whenthe resources are “available to safely insert and subsequent-ly manage intraspinal infusions, it is essential the institutiondevelop the necessary policies, procedures, and competen-cies to support the healthcare professionals involved in thecare of these patients.”

As Stearns et al. indicates, “clinical care should beguided by the best current evidence with the application ofdata from randomized trials when available” (3, page 408).Despite limited evidence specifically related to the role ofintraspinal opioids, it remains our assertion that the totalbody of evidence currently available combined withopinion achieved through expert consensus [3–5] supportsthe availability and use of intraspinal analgesia in thesetting of cancer pain management. In our conclusion, wewere careful to note that patients must be appropriatelyselected. Although exact numbers are unclear, it is a verysmall percentage of patients with cancer whose pain isrefractory to all conventional strategies and/or experiencedose limiting analgesic-related side effects. By no meansdid we intend to suggest intraspinal analgesia shouldbecome, as Drs. Bruera and Hui state, “part of routinecare”. For the sole reason appropriate or carefully selectedpatients do exist, we remain firm in our suggestion thatalthough clinical circumstances necessitating considerationof intraspinal analgesia are rare, comprehensive cancercenters have a responsibility to ensure this small group of

J. Myers (*)Palliative Care Consult Team, Odette Cancer Centre,Sunnybrook Health Sciences,Toronto, ON, Canadae-mail: jeff.myers@sunnybrook.ca

Support Care Cancer (2010) 18:1239–1240DOI 10.1007/s00520-010-0965-z

patients have access to the necessary clinical resources andprofessional expertise allowing safe implementation of thiscancer pain management strategy. We appreciate thethoughtfulness of Drs. Bruera and Hui to raise anopportunity for us to ensure our message is clear and lookforward to ongoing discussions in the literature on thisimportant topic.

Conflict of interest None.

References

1. Myers J, Chan V, Jarvis V, Walker-Dilks C (2010) Intraspinaltechniques for pain management in cancer patients: a systematicreview. Support Care Cancer 18(2):137–149

2. Smith TJ, Staats PS, Deer T, Stearns LJ, Rauck RL, Boortz-Marx RL et al (2002) Randomized clinical trial of animplantable drug delivery system compared with comprehensivemedical management for refractory cancer pain: impact on pain,drug-related toxicity, and survival. J Clin Oncol 20(19):4040–4049

3. Stearns L, Boortz-Marx R, Du Pen S, Friehs G, Gordon M, HalyardM et al (2005) Intrathecal drug delivery for the management ofcancer pain: a multidisciplinary consensus of best clinical practices.J Support Oncol 3(6):399–408

4. Hassenbusch SJ, Portenoy RK, Cousins M, Buchser E, Deer TR,Du Pen SL et al (2004) Polyanalgesic consensus conference 2003:an update on the management of pain by intraspinal drug delivery—report of an expert panel. J Pain Symptom Manage 27(6):540–563

5. Bennett G, Burchiel K, Buchser E, Classen A, Deer T, Du Pen S etal (2000) Clinical guidelines for intraspinal infusion: report of anexpert panel. PolyAnalgesic Consensus Conference 2000. J PainSymptom Manage 20(2):S37–S43

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