Prolonged Opioid Use and Pain Outcome and Associated Factors after Surgery under General Anesthesia: A Prospective Cohort Association Multicenter Study.

BACKGROUND: There is insufficient prospective evidence regarding the relationship between surgical experience and prolonged opioid use and pain. The authors investigated the association of patient characteristics, surgical procedure, and perioperative anesthetic course with postoperative opioid consumption and pain 3 months postsurgery. The authors hypothesized that patient characteristics and intraoperative factors predict opioid consumption and pain 3 months postsurgery. METHODS: Eleven U.S. and one European institution enrolled patients scheduled for spine, open thoracic, knee, hip, or abdominal surgery, or mastectomy, in this multicenter, prospective observational study. Preoperative and postoperative data were collected using patient surveys and electronic medical records. Intraoperative data were collected from the Multicenter Perioperative Outcomes Group database. The association between postoperative opioid consumption and surgical site pain at 3 months, elicited from a telephone survey conducted at 3 months postoperatively, and demographics, psychosocial scores, pain scores, pain management, and case characteristics, was analyzed. RESULTS: Between September and October 2017, 3,505 surgical procedures met inclusion criteria. A total of 1,093 cases were included; 413 patients were lost to follow-up, leaving 680 (64%) for outcome analysis. Preoperatively, 135 (20%) patients were taking opioids. Three months postsurgery, 96 (14%) patients were taking opioids, including 23 patients (4%) who had not taken opioids preoperatively. A total of 177 patients (27%) reported surgical site pain, including 45 (13%) patients who had not reported pain preoperatively. The adjusted odds ratio for 3-month opioid use was 18.6 (credible interval, 10.3 to 34.5) for patients who had taken opioids preoperatively. The adjusted odds ratio for 3-month surgical site pain was 2.58 (1.45 to 4.4), 4.1 (1.73 to 8.9), and 2.75 (1.39 to 5.0) for patients who had site pain preoperatively, knee replacement, or spine surgery, respectively. CONCLUSIONS: Preoperative opioid use was the strongest predictor of opioid use 3 months postsurgery. None of the other variables showed clinically significant association with opioid use at 3 months after surgery.

An Observational Study of the Pharmacokinetics of Surgeon-Performed Intercostal Nerve Blockade With Liposomal Bupivacaine for Posterior-Lateral Thoracotomy Analgesia.

BACKGROUND: Intercostal nerve blocks with liposomal bupivacaine are commonly used for thoracic surgery pain management. However, dose scheduling is difficult because the pharmacokinetics of a single-dose intercostal injection of liposomal bupivacaine has never been investigated. The primary aim of this study was to assess the median time to peak plasma concentration (Tmax) following a surgeon-administered, single-dose infiltration of 266 mg of liposomal bupivacaine as a posterior multilevel intercostal nerve block in patients undergoing posterolateral thoracotomy. METHODS: We chose a sample size of 15 adults for this prospective observational study. Intercostal injection of liposomal bupivacaine was considered time 0. Serum samples were taken at the following times: 5, 15, and 30 minutes, and 1, 2, 4, 8, 12, 24, 48, 72, and 96 hours. The presence of sensory blockade, rescue pain medication, and pain level were recorded after the patient was able to answer questions. RESULTS: Forty patients were screened, and 15 patients were enrolled in the study. Median (interquartile range [IQR]) Tmax was 24 (12) hours (confidence interval [CI], 19.5-28.5 hours) with a range of 15 minutes to 48 hours. The median (IQR) peak plasma concentration (Cmax) was 0.6 (0.3) µg/mL (CI, 00.45-0.74 µg/mL) in a range of 0.3-1.2. The serum bupivacaine concentration was undetectable (<0.2 µg/mL) at 96 hours in all patients. There was significant variability in reported pain scores and rescue opioid medication across the 15 patients. More than 50% of patients had return of normal chest wall sensation at 48 hours. All patients had resolution of nerve blockade at 96 hours. No patients developed local anesthetic toxicity. CONCLUSIONS: This study of the pharmacokinetics of liposomal bupivacaine following multilevel intercostal nerve blockade demonstrates significant variability and delay in systemic absorption of the drug. Peak serum concentration occurred at 48 hours or sooner in all patients. The serum bupivacaine concentration always remained well below the described toxicity threshold (2 µg/mL) during the 96-hour study period.

Multicenter Perioperative Outcomes Group Enhanced Observation Study Postoperative Pain Profiles, Analgesic Use, and Transition to Chronic Pain and Excessive and Prolonged Opioid Use Patterns Methodology.

To study the impact of anesthesia opioid-related outcomes and acute and chronic postsurgical pain, we organized a multicenter study that comprehensively combined detailed perioperative data elements from multiple institutions. By combining pre- and postoperative patient-reported outcomes with automatically extracted high-resolution intraoperative data obtained through the Multicenter Perioperative Outcomes Group (MPOG), the authors sought to describe the impact of patient characteristics, preoperative psychological factors, surgical procedure, anesthetic course, postoperative pain management, and postdischarge pain management on postdischarge pain profiles and opioid consumption patterns. This study is unique in that it utilized multicenter prospective data collection using a digital case report form integrated with the MPOG framework and database. Therefore, the study serves as a model for future studies using this innovative method. Full results will be reported in future articles; the purpose of this article is to describe the methods of this study.

Safety profile of intraoperative methadone for analgesia after major spine surgery: An observational study of 1,478 patients.

OBJECTIVE: To investigate the incidence of perioperative adverse events in patients receiving intravenous methadone for major spine surgery. DESIGN: Retrospective review of perioperative records from March 2011 and February 2016. SETTING: University of Virginia Healthsystem. PATIENTS: Adult patients undergoing elective spinal fusion of two or more levels. MAIN OUTCOME MEASURES: Incidence of respiratory depression, time to extubation, hypotension, hypoxemia, reintubation, cardiac complications, and death. RESULTS: Reviewed 1,478 patient records. Mean intraoperative methadone dose was 0.14 ± 0.07 mg/kg. A total of 1,142 patients (77.4 percent) were extubated in the operating room, 543 (36.8 percent) experienced respiratory depression, 1,180 (79.8 percent) hypoxemia, and 22 (1.5 percent) required reintubation. Cardiac complications included arrhythmias (289 patients, 29.9 percent), QTc prolongation (568 patients, 58.8 percent), and myocardial infarction (16 patients, 1.1 percent). Two in hospital deaths occurred (0.14 percent). CONCLUSIONS: Mild-moderate respiratory depression is observed following a one-time dose of intraoperative methadone, and monitoring in an appropriate postoperative setting is recommended.