Portenoy et al developed a diagnostic algorithm for breakthrough pain, which necessitated the presence of controlled background pain [1]. Recently, Davies et al adapted the original diagnostic algorithm for breakthrough pain; the updated algorithm utilizes stricter criteria for controlled background pain than the original algorithm (Figure 1) [2].

On the basis of the above, the term breakthrough pain should not be used to describe episodes of pain that occur during the initiation and / or titration of opioid analgesics, since the patient clearly does not have controlled background pain in this situation [2]. Such episodes of pain should be termed either a “background pain flare”, or simply an “exacerbation of background pain” [2].

Similarly, the term breakthrough pain should not be used to describe episodes of pain that occur before the administration of opioid analgesics (“end of dose failure”), since the patient again does not have controlled background pain in this situation [2]. It should be noted, however, that end-of-dose failure is regarded as a subtype of breakthrough pain by some experts in the field.

Figure 1 – Algorithm for diagnosing patients with breakthrough pain [2].

References

[1]. Portenoy RK, Payne D, Jacobsen P. Breakthrough pain: characteristics and impact in patients with cancer pain. Pain 1999; 81(1-2): 129-34.

[2]. Davies AN, Dickman A, Reid C, Stevens AM, Zeppetella G. The management of cancer-related breakthrough pain: recommendations of a task group of the Science Committee of the Association for Palliative Medicine of Great Britain and Ireland. European Journal of Pain 2009; 13(4): 331-8.