Economic Considerations of Acute Pain Medicine Programs

Tramadol/Diclofenac Fixed-Dose Combination for Acute Pain Management: Bioavailability Assessment of a Generic Product

The multimodal analgesia strategy for acute pain involves using 2 or more analgesic medications with distinct mechanisms of action. This study assessed the bioavailability and tolerability of 2 tramadol hydrochloride (50 mg)/diclofenac sodium (50 mg) fixed-dose combination formulations under fed conditions to attend the Brazilian regulatory requirements for generic product registration. An open-label, randomized, single-dose, 2-period, 2-way crossover trial was conducted, including healthy subjects of both sexes. Subjects received a single dose of either the test or reference formulation of tramadol/diclofenac fixed-dose combination tablets with a 7-day washout period. Blood samples were collected up to 36 hours after dosing for tramadol and 12 hours for diclofenac and quantified using a validated liquid chromatography-tandem mass spectrometry method. Of 56 subjects enrolled, 53 completed the study. The 90% confidence intervals for maximum plasma concentration and area under the concentration-time curve from time 0 to the last quantifiable concentration were within acceptable bioequivalence limits of 80%-125%. Considering the results presented in this study, the test formulation is bioequivalent to the reference formulation and could be interchangeable in medical practice.

Effect of Opioids on All-cause Mortality and Opioid Addiction in Total Hip Arthroplasty: a Korea Nationwide Cohort Study

BACKGROUND

The purpose of this study was to investigate the use of opioids before and after total hip arthroplasty (THA), to find out the effect of opioid use on mortality in patients with THA, and to analyze whether preoperative opioid use is a risk factor for sustained opioid use after surgery using Korean nationwide cohort data.

METHODS

This retrospective nationwide study identified subjects from the Korean National Health Insurance Service-Sample cohort (NHIS-Sample) compiled by the Korean NHIS. The index date (time zero) was defined as 90 days after an admission to a hospital to fulfill the eligibility criteria of the THA.

RESULTS

In the comparison of death risk according to current use and the defined daily dose of tramadol and strong opioids in each patient group according to past opioid use, there were no statistically significant differences in the adjusted hazard ratio for death compared to the current non-users in all groups (P > 0.05). Past tramadol and strong opioid use in current users increased the risk of the sustained use of tramadol and strong opioids 1.45-fold (adjusted rate ratio [aRR]; 95% confidence interval [CI], 1.12-1.87; P = 0.004) and 1.65-fold (aRR; 95% CI, 1.43-1.91; P < 0.001), respectively, compared to past non-users.

CONCLUSION

In THA patients, the use of opioids within 6 months before surgery and within 3 months after surgery does not affect postoperative mortality, but a past-use history of opioid is a risk factor for sustained opioid use. Even after THA, the use of strong opioids is observed to increase compared to before surgery.

AAAPT Diagnostic Criteria for Acute Knee Arthroplasty Pain

OBJECTIVE

The relationship between preexisting osteoarthritic pain and subsequent post-total knee arthroplasty (TKA) pain is not well defined. This knowledge gap makes diagnosis of post-TKA pain and development of management plans difficult and may impair future investigations on personalized care. Therefore, a set of diagnostic criteria for identification of acute post-TKA pain would inform standardized management and facilitate future research.

METHODS

The Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership with the US Food and Drug Administration (FDA), the American Pain Society (APS), and the American Academy of Pain Medicine (AAPM) formed the ACTTION-APS-AAPM Pain Taxonomy (AAAPT) initiative to address this goal. A multidisciplinary work group of pain experts was invited to conceive diagnostic criteria and dimensions of acute post-TKA pain.

RESULTS

The working group used contemporary literature combined with expert opinion to generate a five-dimensional taxonomical structure based upon the AAAPT framework (i.e., core diagnostic criteria, common features, modulating factors, impact/functional consequences, and putative mechanisms) that characterizes acute post-TKA pain.

CONCLUSIONS

The diagnostic criteria created are proposed to define the nature of acute pain observed in patients following TKA.