Opioid-Sparing Effects of the Bupivacaine Pleural Catheter in Surgical Decompression of the Thoracic Outlet.

BACKGROUND: Rib resection in thoracic outlet decompression can result in significant postoperative pain requiring high levels of opioid medications. We evaluated the impact of a bupivacaine infusing pleural catheter on postoperative pain and opioid usage in patients undergoing rib resection for thoracic outlet syndrome. We hypothesized that delivery of local anesthetic via the pleural catheter would improve postoperative pain control compared to standard multimodal analgesia, and that the use of the catheter would decrease opioid use during the index hospitalization and prescriptions for opioid pain medications at discharge. METHODS: We conducted a single-center retrospective cohort study of 26 patients who underwent rib resection for thoracic outlet decompression. Primary outcome was opioid consumption during the index hospitalization, measured in morphine milligram equivalents (MME). Secondary outcomes were MME prescribed at discharge and pain scores during the index hospitalization before and after the pleural drain and pleural catheter were removed. RESULTS: Patients in the bupivacaine infusion pleural catheter group (n = 11) had significantly lower MME usage during the index hospitalization (22.5 [1.9, 65.6] vs. 119.8 [76.5, 167.4]), and significantly lower MME prescribed at discharge (0 [0, 37.5] vs. 225 [183, 315]), compared to standard multimodal analgesia in controls (n = 15). Only 3 patients in the bupivacaine pleural catheter group were discharged with any opioid prescriptions (27%), compared to 14 patients in the control group (93%). There was no difference in postoperative pain scores between groups before or after removal of the pleural drain, which was placed in all cases (P = 0.31 and P = 0.76, respectively). CONCLUSIONS: Intraoperative placement of a bupivacaine infusion pleural catheter significantly reduced opioid use during the index hospitalization and opioid prescribing at discharge. Anesthetic infusion pleural catheters should be the treatment modality of choice for postoperative pain management in patients undergoing thoracic outlet decompression.

Non-inferiority study assessing the utility of postcervical and lumbar radiofrequency ablation steroid use.

INTRODUCTION: Many physicians administer steroids after radiofrequency ablation (RFA) to mitigate postprocedural inflammation and decrease postprocedural pain. However, robust evidence supporting the benefits of steroids after RFA is lacking and steroids have risks. METHODS: This study was a single-center, prospective, observational study designed to assess whether RFA alone is inferior to RFA with steroids for postprocedure pain. Eligible patients were at least 18 years of age and scheduled to undergo cervical or lumbar RFA. The primary outcome measure was the average pain score on the numeric rating scale (NRS) 7 days after the RFA. The secondary outcome measures included anxiety, depression and physical function, measured via the Patient-Reported Outcomes Measurement Information System short forms. All outcome measures were completed prior to the procedure and at 7 and 60 days postprocedure. RESULTS: Out of the 365 participants who completed baseline assessments, 175 received steroids and 190 did not receive steroids. The pain intensity at 7 days postprocedure was similar between the steroid and non-steroid groups (mean difference (steroid-non-steroid): -0.23). The 95% CI of the estimate (-0.76 to 0.30) was within the prespecified non-inferiority margin of 1.5 NRS points. Similar results were obtained for pain at 60 days (mean difference: 0.09; 95% CI -0.48 to 0.65). No significant differences between groups were observed for anxiety, depression or physical function at either 7 or 60 days. CONCLUSION: This study suggests that the addition of steroids to the RFA procedure does not provide added benefits and is therefore not worth the additional risks that they pose.

Evaluating predictors of pain reduction after genicular nerve radiofrequency ablation for chronic knee pain.

Aim: Radiofrequency ablation (RFA) of genicular nerves can treat refractory chronic knee pain. This study evaluated association between patient and procedural characteristics and pain improvement after genicular nerve RFA. Materials & methods: A retrospective chart review. Data were extracted from patients who underwent thermal or cooled RFA of the knee. Results: A total of 124 patients were included. 81% of patients reported ≥75% pain relief after diagnostic nerve blocks. 35% reported ≥50% pain reduction from the RFA. Predictors of improved pain outcomes included higher baseline pain, no depression and thermal (vs cooled) RFA. Conclusion: Identifying patients who may benefit the most from genicular RFA is still not clear. Pain reduction differences between patients with and without depression and RFA type deserves further exploration.

Lay abstract Aim: Using heat energy to stun the nerves (Radiofrequency ablation) that supply knee joint is a technique that can be used to decrease persistent knee pain. This study was performed to try to see if there are any ways that doctors are able to predict which patients will benefit from this therapy. Materials & methods: The data were collected by reviewing charts. Results: A total of 124 patients were included in this study. The data did not show that good pain relief after diagnostic injection guaranteed success with this technique of stunning of the nerve with heat energy (RFA). The things that can possibly predict success are more severe pain to start with, people who do not suffer from depression and use of higher level of heat energy to stun the nerves. Conclusion: It is still not clear which patients will benefit from this technique of stunning the nerves of the knee with heat energy.

Reporting of sample size calculations in analgesic clinical trials: ACTTION systematic review.

UNLABELLED: Sample size calculations determine the number of participants required to have sufficiently high power to detect a given treatment effect. In this review, we examined the reporting quality of sample size calculations in 172 publications of double-blind randomized controlled trials of noninvasive pharmacologic or interventional (ie, invasive) pain treatments published in European Journal of Pain, Journal of Pain, and Pain from January 2006 through June 2013. Sixty-five percent of publications reported a sample size calculation but only 38% provided all elements required to replicate the calculated sample size. In publications reporting at least 1 element, 54% provided a justification for the treatment effect used to calculate sample size, and 24% of studies with continuous outcome variables justified the variability estimate. Publications of clinical pain condition trials reported a sample size calculation more frequently than experimental pain model trials (77% vs 33%, P < .001) but did not differ in the frequency of reporting all required elements. No significant differences in reporting of any or all elements were detected between publications of trials with industry and nonindustry sponsorship. Twenty-eight percent included a discrepancy between the reported number of planned and randomized participants. This study suggests that sample size calculation reporting in analgesic trial publications is usually incomplete. Investigators should provide detailed accounts of sample size calculations in publications of clinical trials of pain treatments, which is necessary for reporting transparency and communication of pre-trial design decisions. PERSPECTIVE: In this systematic review of analgesic clinical trials, sample size calculations and the required elements (eg, treatment effect to be detected; power level) were incompletely reported. A lack of transparency regarding sample size calculations may raise questions about the appropriateness of the calculated sample size.

Reporting of intention-to-treat analyses in recent analgesic clinical trials: ACTTION systematic review and recommendations.

The intention-to-treat (ITT) principle states that all subjects in a randomized clinical trial (RCT) should be analyzed in the group to which they were assigned, regardless of compliance with assigned treatment. Analyses performed according to the ITT principle preserve the benefits of randomization and are recommended by regulators and statisticians for analyses of RCTs. The objective of this study was to determine the frequency with which publications of analgesic RCTs in 3 major pain journals report an ITT analysis and the percentage of the author-declared ITT analyses that include all randomized subjects and thereby fulfill the most common interpretation of the ITT principle. RCTs investigating noninvasive, pharmacologic and interventional (eg, nerve blocks, implantable pumps, spinal cord stimulators, surgery) treatments for pain, published between January 2006 and June 2013 (n=173), were included. None of the trials using experimental pain models reported an ITT analysis; 47% of trials investigating clinical pain conditions reported an ITT analysis, and 5% reported a modified ITT analysis. Of the analyses reported as ITT, 67% reported reasons for excluding subjects from the analysis, and 18% of those listing reasons for exclusion did not do so in the Methods section. Such mislabeling can make it difficult to identify traditional ITT analyses for inclusion in meta-analyses. We hope that deficiencies in reporting identified in this study will encourage authors, reviewers, and editors to promote more consistent use of the term "intention to treat" for more accurate reporting of RCT-based evidence for pain treatments.