A practical guide to adopting Bayesian analyses in clinical research.

Background: Bayesian statistical approaches are extensively used in new statistical methods but have not been adopted at the same rate in clinical and translational (C&T) research. The goal of this paper is to accelerate the transition of new methods into practice by improving the C&T researcher's ability to gain confidence in interpreting and implementing Bayesian analyses. Methods: We developed a Bayesian data analysis plan and implemented that plan for a two-arm clinical trial comparing the effectiveness of a new opioid in reducing time to discharge from the post-operative anesthesia unit and nerve block usage in surgery. Through this application, we offer a brief tutorial on Bayesian methods and exhibit how to apply four Bayesian statistical packages from STATA, SAS, and RStan to conduct linear and logistic regression analyses in clinical research. Results: The analysis results in our application were robust to statistical package and consistent across a wide range of prior distributions. STATA was the most approachable package for linear regression but was more limited in the models that could be fitted and easily summarized. SAS and R offered more straightforward documentation and data management for the posteriors. They also offered direct programming of the likelihood making them more easily extendable to complex problems. Conclusion: Bayesian analysis is now accessible to a broad range of data analysts and should be considered in more C&T research analyses. This will allow C&T research teams the ability to adopt and interpret Bayesian methodology in more complex problems where Bayesian approaches are often needed.

Comparing liposomal bupivacaine plus bupivacaine to bupivacaine alone in interscalene blocks for rotator cuff repair surgery: a randomized clinical trial.

BACKGROUND: Single-injection interscalene brachial plexus blocks are used for analgesia for rotator cuff repair (RCR) but have limited duration. The value of adding liposomal bupivacaine (LB) to prolong single-injection interscalene blocks is unclear. The purpose of this trial is to evaluate the addition of LB to regular bupivacaine interscalene blocks for patients undergoing arthroscopic RCR. METHODS: In this prospective, randomized trial, 70 patients undergoing primary RCR with equal group allocation were randomized by random number generator to receive an interscalene block with 20 mL of 0.5% bupivacaine or 10 mL 0.5% bupivacaine plus 133 mg LB. The primary outcome was cumulative opioid consumption within 72 hours of the procedure. Secondary outcomes included maximum pain scores and quality of recovery 15 survey scores. RESULTS: 70 of the 80 randomized patients were included in final analysis following exclusion for protocol violations and loss to follow-up. Cumulative opioid consumption (oral morphine equivalents) within 72 hours in patients receiving LB was a median (IQR) of 31.9 mg (0, 73.1) compared with 45.0 mg (15.0, 108.8) among patients receiving bupivacaine alone (p=0.312). Patients receiving LB demonstrated mixed results regarding worst pain scores with improvements at 24 hours and 72 hours, but not 48 hours. CONCLUSIONS: LB added to bupivacaine interscalene blocks does not reduce opioid consumption within 72 hours following arthroscopic RCR. TRIAL REGISTRATION NUMBER: NCT03587584.

Evaluation of Diaphragmatic Function after Interscalene Block with Liposomal Bupivacaine: A Randomized Controlled Trial.

BACKGROUND: Interscalene blocks provide analgesia for shoulder surgery but also cause phrenic nerve paralysis. Liposomal bupivacaine is approved for use in interscalene blocks with the potential to provide longer pain control. However, the impact of liposomal bupivacaine on the phrenic nerve has not been evaluated. It was hypothesized that patients who received an interscalene block with both bupivacaine and liposomal bupivacaine would have a decreased diaphragmatic excursion when compared to bupivacaine alone at 24 h. METHODS: This was a double-blinded study of adult patients who were randomized to receive an interscalene block with either 20 ml 0.5% bupivacaine (bupivacaine group) or 10 ml 0.5% bupivacaine plus 10 ml liposomal bupivacaine (liposomal bupivacaine group). Twenty-six patients were randomized with 22 included in the analysis. Diaphragmatic excursion (via ultrasound) and spirometry were assessed before the block, in the postanesthesia care unit, and at 24 h postblock. The primary outcome was diaphragm excursion with sigh. No adverse events were observed. RESULTS: At 24 h, the liposomal bupivacaine group median [25th, 75th], had a greater percent change in diaphragmatic excursion during sigh breath compared to the bupivacaine group, -24% [-30, -9] versus 9% [-8, 26], difference in location, 32 (95% CI, 12 to 52), P = 0.007. Five patients in the liposomal bupivacaine group had a greater than 25% reduction in diaphragmatic excursion at 24 h versus zero in the bupivacaine group. They also had a significantly greater percent reduction in forced expiratory volume in 1 s and forced vital capacity compared with the bupivacaine group at 24 h (median decrease of 22% vs. 2%, P = 0.006, and median decrease of 19% vs. 1%, P = 0.049, respectively). CONCLUSIONS: The addition of liposomal bupivacaine to bupivacaine in an interscalene block results in statistically significant reductions in diaphragm excursion and pulmonary function testing 24 h after block placement when compared to bupivacaine alone. This reduction, however, falls within the range of normal diaphragmatic function.

Patient Complications after Interscalene Block: A Retrospective Comparison of Liposomal Bupivacaine to Nonliposomal Bupivacaine.

BACKGROUND: The purpose of this study was to investigate if the addition of liposome bupivacaine (LB) to an interscalene block (ISB) had an effect on the number of patients with surgical- or block-related complications. METHODS: This was a single-center retrospective chart view performed by identifying patients who received an ISB from January 1, 2014, through April 26, 2018, at the University of Minnesota. 1,518 patients were identified who received an ISB (LB = 784, nonliposomal bupivacaine = 734). Patients were divided into two groups those who did receive liposome bupivacaine in their ISB and those who did not receive liposome bupivacaine in their ISB. Medical records were individually reviewed for surgical procedure, block medications, complications related to the block or surgical procedure, phone calls to the healthcare system for issues related to opioids or pain within 3 and within 30 days, readmissions within 30 days, and emergency room visits for complications within 3 and 30 days. RESULTS: There was no significant difference in the number of patients with surgical or anesthetic complications. Only phone calls for pain within 3 days were significantly different. The LB group had 3.2% of patients call compared to 5.6% in the nonliposomal bupivacaine group (aOR = 1.71 (95% CI: 1.04-2.87), p=0.036). We found no significant difference in any of the other secondary outcomes. CONCLUSIONS: The use of LB in an ISB demonstrated no significant difference compared to nonliposomal bupivacaine in numbers of complications, emergency room visits, and readmissions.

Pooled Dosing and Efficacy Analysis of the Sufentanil Sublingual Tablet 30 mcg Across Demographic Subgroups for the Management of Moderate-to-Severe Acute Pain.

PURPOSE: To aid nurses in dosing sufentanil sublingual tablet (SST) 30 mcg administered via a single-dose applicator, dosing requirements and efficacy of SST 30 mcg were analyzed across age, sex, race, and body mass index subgroups. DESIGN: Patient characteristics were pooled from three postoperative studies (two placebo-controlled and one open-label) and one open-label emergency department study. Drug dosing and efficacy data were pooled from the postoperative studies. METHODS: Efficacy was assessed through summed pain intensity difference to baseline during 12 hours across subgroups. FINDINGS: Mean (standard deviation) drug doses administered from 0 to 12 hours was 3.9 (2.0) for SST 30 mcg and was less frequent for older (≥65 years) versus younger patients. The summed pain intensity difference to baseline during 12 hours was superior with SST 30 mcg versus placebo across all subgroups. CONCLUSIONS: SST 30 mcg is a sublingual opioid analgesic with efficacy across demographic subgroups.

The addition of intrathecal morphine to a transversus abdominis plane block with liposome bupivacaine provides more effective analgesia than transversus abdominis plane block with liposome bupivacaine alone: a retrospective study.

OBJECTIVE: The purpose of this study was to determine if the standardization of using liposomal bupivacaine in transversus abdominis plane (LB TAP) blocks eliminated the benefit of intrathecal morphine (ITM) in patients after undergoing a cesarean section. METHODS: This was a retrospective review of 358 patients who underwent cesarean section over an 11-month period. Patients were divided into two groups: those who received only an LB TAP (67 patients) vs those who received an LB TAP and ITM (291 patients). All blocks were placed bilaterally under ultrasound guidance after closure of the surgical incision, and morphine was added to the spinal used for the case. RESULTS: The group that received ITM in addition to the LB TAP received less opioids in the first 24 hours (median 5 range 0-150 mg morphine equivalents [ME] vs 15 range 0-76 mg ME; P<0.001) and less opioids overall (35 mg range 0-450 mg ME vs 47.5 mg range 0-189 mg ME; P=0.041) when compared to the LB TAP block only group. There was no difference between the two groups in opioid use from 24 to 48 hours or 48 to 72 hours. CONCLUSION: Patients who received ITM in addition to an LB TAP block received less opioids in the first 24 hours and overall when compared to those who received an LB TAP alone. This suggests that ITM still plays a role in providing analgesia to patients who have also received an LB TAP block as a part of their multimodal pain regimen for cesarean sections.

Thoracic paravertebral block versus thoracic epidural analgesia for post-operative pain control in open pancreatic surgery: A randomized controlled trial.

STUDY OBJECTIVE: The purpose of this study was to compare the efficacy of bilateral ultrasound guided thoracic paravertebral catheters to a thoracic epidural after open pancreatic surgery. DESIGN: This was a prospective non-blinded randomized controlled trial. SETTING: Academic hospital operating room, postoperative recovery area, and ward. PATIENTS: 53 patients aged 18 and above who had open pancreatic surgery. INTERVENTIONS: Patients received either bilateral thoracic paravertebral block at T8 with an infusion of 0.2% ropivacaine or thoracic epidural analgesia at T7/8 with an infusion of 0.125% bupivacaine with hydromorphone 6 µg/mL. MEASUREMENTS: Pain scores, opioid use, length of recovery room and hospital stay, adverse events, and incidence of nausea and vomiting. MAIN RESULTS: There was no difference in baseline demographics between the two groups. There were no significant differences in pain scores between the two groups in each of the first five days after surgery. There was no difference in length of stay nor nausea and vomiting. There was significantly less modality related adverse events in the paravertebral group compared to the epidural group (p = 0.02). CONCLUSIONS: The use of thoracic paravertebral catheters provided comparable analgesia and less modality related adverse events when compared to a thoracic epidural in patients undergoing open pancreaticoduodenectomy.

An Open-Label Study of Sufentanil Sublingual Tablet 30 Mcg in Patients with Postoperative Pain.

Objective: To evaluate sufentanil sublingual tablet 30 mcg (SST 30 mcg) for postoperative pain in an older patient population with comorbidities. Design: Multicenter, open-label, single-arm study. Setting: Nine hospitals across the United States. Subjects: Adults aged ≥40 years who had undergone a surgical procedure. Methods: Patients with a postoperative pain intensity score ≥4 on an 11-point numeric rating scale (NRS) were allowed to enter the study and receive SST 30 mcg as requested for pain (minimum 60-minute redosing interval) over the 12-hour study period. Efficacy was assessed by patient reports of pain intensity on the NRS and a five-point pain relief scale. Safety was monitored throughout the study; plasma sufentanil concentrations were also measured. The primary efficacy endpoint was the time-weighted summed pain intensity difference (SPID) to baseline over 12 hours (SPID12). Results: Of the 140 patients enrolled, 69% were American Society of Anesthesiologists Physical Class II or III, 44% had a body mass index (BMI) ≥30 mg/kg2, and 29% had hepatic and/or renal impairment. Average age was 54.7 years (SD = 9.9 years), and average baseline pain intensity was 6.2 (SD = 1.9). The most common surgeries were abdominal (59%) and orthopedic (20%). The mean SPID12 was 36.0 (standard error of the mean = 2.2); mean scores were similar, regardless of age, sex, race, and BMI. From baseline, mean pain intensity decreased significantly starting 30 minutes postdose, and mean pain relief increased significantly starting 15 minutes postdose, remaining relatively stable through 12 hours (P < 0.001 at each time point). Four (3%) patients discontinued due to inadequate analgesia, and 45 (32%) patients had one or more adverse events that were considered possibly or probably related to the study drug. Mean plasma sufentanil concentrations were generally similar regardless of age, sex, BMI, or organ impairment status. Conclusions: SST 30 mcg was effective and well tolerated for the management of moderate-to-severe acute postoperative pain.

Thoracic paravertebral catheter placement for acute rib pain in a pregnant patient with cystic fibrosis.

A 30-year-old woman with cystic fibrosis at 33 weeks, 4 days' gestation sustained a rib injury during an acute pulmonary exacerbation, resulting in noncompliance with her chest wall oscillation therapy and worsening of her respiratory status with concern for inducing labor early. Insertion of an ultrasound-guided thoracic paravertebral catheter produced immediate pain relief, eliminating the need for further opioids, and she was able to tolerate her chest wall oscillation treatment. She was discharged home after 7 days and was able to deliver a healthy baby at 38 weeks via spontaneous vaginal delivery.