SABER-Bupivacaine Reduces Postoperative Pain and Opioid Consumption After Arthroscopic Subacromial Decompression: A Randomized, Placebo-Controlled Trial

INTRODUCTION

Shoulder arthroscopy can result in substantial postoperative pain. Sucrose acetate isobutyrate extended-release bupivacaine (SABER-Bupivacaine; trade name Posimir) is a novel depot formulation of bupivacaine designed to provide analgesia at the surgical site for up to 72 hours. The objective of this study was to evaluate the effect of SABER-Bupivacaine on pain and opioid consumption after arthroscopic subacromial decompression and to assess short-term and long-term safety.

METHODS

In this double-blind, placebo-controlled trial, 78 subjects were randomized in a 2:1 ratio to SABER-Bupivacaine 5 mL or SABER-placebo 5 mL injected into the subacromial space just before skin closure. Twenty-nine additional subjects were randomized on an exploratory basis to bupivacaine hydrochloride 20 mL, also injected subacromially. Subjects rated pain intensity on a 0 to 10 scale over the first 3 postoperative days and received intravenous or oral morphine for breakthrough pain. The coprimary efficacy end points were pain intensity on 90° shoulder flexion and cumulative morphine intake from 0 to 72 hours after surgery. The time to first use of opioid rescue analgesia was a secondary end point.

RESULTS

The mean (SD) pain intensity was 5.16 (1.94) for SABER-Bupivacaine and 6.43 (1.77) for placebo (P = 0.012). The median consumption of intravenous morphine equivalents was 4.0 mg for SABER-Bupivacaine and 12.0 mg for placebo (P = 0.010). The median time to first use of morphine rescue was 12.4 hours for SABER-Bupivacaine and 1.2 hours for placebo (P = 0.014). The corresponding values for bupivacaine hydrochloride were 5.16 (2.38), 8.0 mg, and 1.4 hours. The incidence and severity of treatment-emergent adverse events were similar for all treatment groups, and no functional or radiographic differences were noted at the 6-month follow-up.

DISCUSSION

Compared with placebo, SABER-Bupivacaine reduced pain and opioid analgesic consumption over 72 hours after arthroscopic subacromial decompression and prolonged the time to first use of opioid rescue analgesia. No safety signals were noted during the immediate postoperative period or at 6-month follow-up.

Safety and efficacy of switching from low molecular weight heparin to dabigatran in patients undergoing elective total hip or knee replacement surgery

Background

The aim of this study was to assess the safety and efficacy of switching therapy from low molecular weight heparin (LMWH; enoxaparin) to dabigatran for prevention of venous thromboembolic events (VTE) in patients undergoing elective total hip or knee replacement surgery (THR/TKR).

Methods

This was a prospective, multicenter, open-label, single-arm, observational, study in patients undergoing THR or TKR who were to receive enoxaparin 40 mg for thromboprophylaxis. Enoxaparin was initiated before or after surgery according to local practice, and was switched to dabigatran 220 mg once daily at a time point chosen by the investigator. The coprimary endpoints were major bleeding events, and the composite of symptomatic VTE and all-cause mortality, from last use of enoxaparin to 24 h after last intake of dabigatran.

Results

Altogether, 168 (81 THR, 87 TKR) patients were enrolled, of whom 161 received both enoxaparin and dabigatran, 2 received dabigatran only and 5 received enoxaparin only. The median time of the first dabigatran tablet was 24.0 h after the last LMWH dosage and the median number of days on dabigatran treatment was 36 days. No symptomatic VTE or death occurred during the study. One major bleeding event was seen at the surgical site and required treatment cessation. Three minor bleeding events were observed.

Conclusions

In the normal clinical setting, switching from LMWH to dabigatran in patients who had undergone THR and TKR was safe and effective in preventing VTE. The reported adverse events and serious adverse events were consistent with the known safety profile for dabigatran. Switching from a subcutaneous to an oral anticoagulant may offer greater convenience in the outpatient setting after discharge.

Trial registration

ClinicalTrials.gov identifier NCT01153698.

[Prevention of venous thromboembolism in musculoskeletal surgery]

Musculoskeletal surgery is associated with a high risk of venous thrombosis and pulmonary embolism. The introduction of direct oral anticoagulants (DOAK) has broadened the possibilities for prevention of venous thromboembolism in the course of orthopedic and trauma surgery. Addressing this recent development, the Austrian Societies of Orthopedics and Orthopedic Surgery (ÖGO), Trauma Surgery (ÖGU), Hematology and Oncology (OeGHO) and of Anaesthesiology, Reanimation und Intensive Care Medicine (ÖGARI) have taken the initiative to create Austrian guidelines for the prevention of thromboembolism after total hip and knee replacement, hip fracture surgery, interventions at the spine and cases of minor orthopedic and traumatic surgery. Furthermore, the pharmacology of the DOAK and the pivotal trial data for each of the three currently available substances - apixaban, dabigatran, and rivaroxaban - are briefly presented. Separate chapters are dedicated to "anticoagulation and neuroaxial anesthesia" and "bridging".

Age predicts outcome of high-tibial osteotomy

This study compares the predictive value of age at surgery in high tibial osteotomy. Twenty-seven high-tibial osteotomies in patients who are 65 years or older (mean age at surgery 68+/-4 years, follow up 12+/-2 years) were compared to 67 osteotomies in patients younger than 65 years (mean age at surgery 56+/-6 years, follow up 13+/-3) with respect to the outcome by Cox regression analysis. Failure, i.e. endpoint, was defined as implantation of a knee endoprosthesis and assessed by Kaplan-Meier analysis. There is a significantly higher risk for failure of high tibial osteotomies in patients of 65 years or more compared to younger patients (failure rate 38.4+/-11.3% vs. 23.1+/-5.8%) resulting in a relative risk of 1.5 (P=0.0461). The hazard of failure increased 7.6% per year of age. We conclude that in regard to the increasing risk of failure per year of age and the higher failure rate in older patients, high-tibial osteotomy should not be performed on patients older than 65 years.