The ACTTION-APS-AAPM Pain Taxonomy (AAAPT) Multidimensional Approach to Classifying Acute Pain Conditions.

Objective: With the increasing societal awareness of the prevalence and impact of acute pain, there is a need to develop an acute pain classification system that both reflects contemporary mechanistic insights and helps guide future research and treatment. Existing classifications of acute pain conditions are limiting, with a predominant focus on the sensory experience (e.g., pain intensity) and pharmacologic consumption. Consequently, there is a need to more broadly characterize and classify the multidimensional experience of acute pain. Setting: Consensus report following expert panel involving the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION), American Pain Society (APS), and American Academy of Pain Medicine (AAPM). Methods: As a complement to a taxonomy recently developed for chronic pain, the ACTTION public-private partnership with the US Food and Drug Administration, the APS, and the AAPM convened a consensus meeting of experts to develop an acute pain taxonomy using prevailing evidence. Key issues pertaining to the distinct nature of acute pain are presented followed by the agreed-upon taxonomy. The ACTTION-APS-AAPM Acute Pain Taxonomy will include the following dimensions: 1) core criteria, 2) common features, 3) modulating factors, 4) impact/functional consequences, and 5) putative pathophysiologic pain mechanisms. Future efforts will consist of working groups utilizing this taxonomy to develop diagnostic criteria for a comprehensive set of acute pain conditions. Perspective: The ACTTION-APS-AAPM Acute Pain Taxonomy (AAAPT) is a multidimensional acute pain classification system designed to classify acute pain along the following dimensions: 1) core criteria, 2) common features, 3) modulating factors, 4) impact/functional consequences, and 5) putative pathophysiologic pain mechanisms. Conclusions: Significant numbers of patients still suffer from significant acute pain, despite the advent of modern multimodal analgesic strategies. Mismanaged acute pain has a broad societal impact as significant numbers of patients may progress to suffer from chronic pain. An acute pain taxonomy provides a much-needed standardization of clinical diagnostic criteria, which benefits clinical care, research, education, and public policy. For the purposes of the present taxonomy, acute pain is considered to last up to seven days, with prolongation to 30 days being common. The current understanding of acute pain mechanisms poorly differentiates between acute and chronic pain and is often insufficient to distinguish among many types of acute pain conditions. Given the usefulness of the AAPT multidimensional framework, the AAAPT undertook a similar approach to organizing various acute pain conditions

Pain ratings by patients and their providers of radionucleotide injection for breast cancer lymphatic mapping

Background. Disparity between patient report and physician perception of pain from radiotracer injection for sentinel node biopsy is thought to center on the severity of the intervention, ethnic composition of population queried, and socioeconomic factors. Objective. The objectives of this study were, first, to explore agreement between physicians' and their breast cancer patients' pain assessment during subareolar radionucleotide injection; and second, to evaluate potential ethnic differences in ratings. Methods. A trial was conducted, from January 2006 to April 2009, where 140 breast cancer patients were randomly assigned to standard topical lidocaine-4% cream and 99mTc-sulfur colloid injection, or to one of three other groups: placebo cream and 99mTc-sulfur colloid injection containing NaHCO3, 1% lidocaine, or NaHCO3 + 1% lidocaine. Providers and patients completed numeric pain scales (0–10) immediately after injection. Results. Patients and providers rated pain similarly over the entire cohort (median, 3 vs 2, P = 0.15). Patients rated pain statistically significantly higher than physicians in the standard (6 vs 5, P = 0.045) and placebo + NaHCO3 (5 vs 4, P = 0.032) groups. No significant difference in scores existed between all African Americans and their physicians (3 vs 4, P = 0.27). Conclusion. Patient–physician pain assessment congruence over the less painful injections and their statistically similar scores with the more painful methods suggests the importance of utilizing the least painful method possible. Providers tended to underestimate patients with the highest pain ratings—those in the greatest analgesic need. Lack of statistical difference between African American and physician scores may reflect the equal-access-to-care over the entire patient cohort, supporting the conclusion that socioeconomic factors may lie at the heart of previously reported discrepancies

Methadone Destabilizes Cardiac Repolarization During Sleep

Methadone, a widely prescribed medication for chronic pain and opioid addiction, is associated with respiratory depression and increased predisposition for torsades de pointes, a potentially fatal arrhythmia. Most methadone-related deaths occur during sleep. The objective of this study was to determine whether methadone's arrhythmogenic effects increase during sleep, with a focus on cardiac repolarization instability using QT variability index (QTVI), a measure shown to predict arrhythmias and mortality. Sleep study data of 24 patients on chronic methadone therapy referred to a tertiary clinic for overnight polysomnography were compared with two matched groups not on methadone: 24 patients referred for overnight polysomnography to the same clinic (clinic group), and 24 volunteers who had overnight polysomnography at home (community group). Despite similar values for heart rate, heart rate variability, corrected QT interval, QTVI, and oxygen saturation (SpO(2)) when awake, patients on methadone had larger QTVI (P = 0.015 vs. clinic, P 1,000 premature beats per median sleep period), a precursor for torsades de pointes, was uncommon but more frequent in patients on methadone (P = 0.039). This study demonstrates that chronic methadone use is associated with increased cardiac repolarization instability. Methadone's pro-arrhythmic impact may be mediated by sleep-related hypoxemia, which could explain the increased nocturnal mortality associated with this opioid