Opioid Poorly-Responsive Cancer Pain. Part 2

Abstract

Basic research in experimental pain models may illuminate the phenomenon of cancer pain that is poorly responsive to opioid drugs. Research findings can be valuable in formulating new strategies in clinical practice. This review evaluated experimental observations in terms of the events that occur in cancer patients receiving opioid therapy for pain.

Pain Experience of Children with Sickle Cell Disease Who Had Prolonged Hospitalizations for Acute Painful Episodes

“…Development of protocols so that all patients receive uniform and aggressive titration for resolution of pain during VOE is recommended. Such protocols would determine whether the persistently high pain ratings in patients with prolonged hospitalizations indicate poor responsiveness to medications [49–51], or suboptimal dosing regimens [38–40]. Several questions emerge from this study that warrant further investigations: 1) What factors are associated with the discrepancy between high pain intensity ratings and low administration of analgesics and the low use of the available prescriptions?…”

A low power, microvalve regulated architecture for drug delivery systems

“…The continuum of treatment modalities for severe chronic pain range from physical therapy and oral medication through the implantation of an intrathecal drug delivery device (IDDD) (Winkelmuller and Winkelmuller 1996;Wermeling 2005;Schug et al 2006, Rauck et al 2003. Advances in technology have led to the development of sophisticated intrathecal drug delivery systems which administer drugs into the cerebrospinal fluid on a continuous basis (Hassenbusch et al 2004;Krames 1999;Rainov and Heidecke 2007;Grabow et al 2001;Anderson and Burchiel 1999;ASHP 2000;Crawford 1980;Baraka 1982;Coombs andFine 1991 Deer et al 2002;Sakurada et al 2005;Mercadante and Portenoy 2001;Mercadante et al 2003). Many of these systems are implantable.…”

The Patient with Difficult Cancer Pain

“…Incident pain is a subtype of breakthrough cancer pain (BTcP). BTcP has been defined as a transient peak of pain that occurs either spontaneously or is triggered by a recognizable cause, despite a stable and well controlled basal pain [3]. In a recent study about 40% of patients with BTcP presented predictable incident pain, prevalently triggered by movement, due to bone metastases [10].…”

“…Neuropathic pain in cancer patients has been consistently described as a negative prognostic factor associated with a decrease in opioid response. However, neuropathic pain does not result in an inherent resistance to opioids, but it may be considered as a prognostic factor limiting a favorable outcome [3]. Other studies assessing the pain prognostic factors have shown that neuropathic pain may require more aggressive pain treatments, which are associated with a larger use of adjuvants and high opioid dosages [3,7,8].…”

“…Analgesics treatments may lose efficacy because dose escalation is not followed by a favorable analgesic response and the therapeutic window is restricted by the development of side effects, despite using symptomatic drugs. A gradual increase in dosage that is not followed by a change in analgesic improvement should suggest that treatment is inefficient, and possibly is creating the conditions for increased neuronal excitability, a phenomenon known as opioid-induced hyperalgesia [3].…”