Comparison of the effectiveness of ultrasound-guided versus fluoroscopy-guided medial lumbar bundle branch block on pain related to lumbar facet joints: a multicenter randomized controlled non-inferiority study.

BACKGROUND: The aim of this multicenter randomized interventional prospective study was to compare the ultrasound (US)-guided lumbar medial branch block (LMBB) with the fluoroscopy (FS)-guided LMBB in terms of analgesic efficacy and disability in the setting of the treatment of pain arising from the lumbar facet joints (LFJ). METHODS: Fifty adults with a "LFJ" syndrome were randomized into two groups: in group FS, fluoroscopic-guidance was used to block the medial branch at three lumbar levels (L3-L4, L4-L5 and L5-S1); in group US, same blocks were performed under ultrasound. Needle transverse approach was used with both techniques. Effects of these procedures were assessed with a Visual Analogue Pain Scale (VAPS), the Oswestry Disability Index (ODI) and the Duke's Activity Status Index (DASI) scale, before the treatment, 1 week and 1 month after. Hospital Anxiety and Depression Scale (HADS) score was also collected before the procedure. Analysis of variance, one (for non-inferiority) and two-sided Mann-Whitney tests and Chi-square tests were performed. RESULTS: LMBB under US-guidance was not inferior to FS-guidance (P = 0.047) in terms of VAPS, ODI and DASI at 1 week and 1 month. Duration of techniques and HADS were similar between groups (=0.34; p = 0.59). CONCLUSIONS: The medial lumbar bundle branch block under ultrasound-guidance is not inferior to the fluoroscopy-guidance procedure in effectively alleviating pain arising from the facet joints. Considering that this ultrasound technique has the benefit of an irradiation-free, real-time procedure, it can be considered as an effective alternative to the fluoroscopy-guided technique.

Influence of height on ED95 of intrathecal 2-chloroprocaine for knee arthroscopy: A prospective dose-response clinical trial.

BACKGROUND: Plain 2-chloroprocaine , a rapid acting amino-ester-type local anaesthetic, is used in short ambulatory procedures under spinal anaesthesia. The ED 95 of 2-chloroprocaine for lower limb surgery has not yet been defined. Moreover, patients' body height could influence the effects of the administered dose. OBJECTIVES: The aim of this study was to determine the ED 95 of plain 2-chloroprocaine based on the height of patients undergoing ambulatory knee arthroscopy under spinal anaesthesia using the continual reassessment statistical method (CRM). DESIGN: Prospective, dose-response, double blind, controlled, bi-center, clinical trial. SETTING: One university teaching hospital in Brussels and one general teaching hospital, Braine l'Alleud, Belgium. Université libre de Bruxelles. PATIENTS: ASA I-III (120 patients) scheduled for day-case knee arthroscopy under spinal anaesthesia. INTERVENTIONS: Patients were divided into three groups of 40, each comprising 10 cohorts of 4 patients, according to their respective heights (Group 1: 150-165 cm, Group 2: 166-180 cm, Group 3: 181-195 cm). Each patient enrolled into one of the 3 groups received an intrathecal dose of plain 2-chloroprocaine determined by the CRM. The starting doses for the first cohorts of four were 40 mg in group 1, 45 mg in group 2 and 50 mg in group 3. The doses for subsequent cohorts were determined by CRM of outcomes in all patients in the previous competed cohorts. Anaesthesia was considered successful when there was a lack of pinprick or cold sensation up to T12, the visual analogue scale score for tourniquet pain was < 2 and no pain during surgery. MAIN OUTCOMES: The primary outcome was the success or failure of the block. Side effects were also recorded. RESULTS: ED 95 of 2-chloroprocaine is 40 mg in group 1, 35 mg in group 2, 45 mg in group 3. Groups were different in terms of height and gender ( P  < 0.05) and similar in terms of body mass index and age ( P  > 0.05). CONCLUSION: The ED95 of intrathecal 2-chloroprocaine for patients undergoing ambulatory knee arthroscopy is between 35 and 45 mg. Height could be a factor involved in the calculation, and patient sex could partly explain the nonlinear relation between height and dose. TRIAL REGISTRY NUMBER: Clinicaltrials.gov NCT03882489.

ED50 and ED90 of intrathecal hyperbaric 2% prilocaine in ambulatory knee arthroscopy.

PURPOSE: Hyperbaric 2% prilocaine (HP) is increasingly used for spinal anesthesia in day-case surgery. The aim of this prospective double-blind study was to determine the effective dose (ED)50 and the ED90 of HP for patients undergoing knee arthroscopy. METHODS: Doses of HP were determined using an up-and-down sequential allocation technique. Sequences were analyzed by isotonic regression analysis. A subsequent observational study was performed with the calculated ED90 in 50 patients to confirm the initial result and to describe the induced blockade effects and side effects. Times corresponding to onset and duration of sensory and motor block, surgical data, and side effects were recorded. RESULTS: The ED50 was estimated at 28.9 mg (95% confidence interval [CI]: 26.5 to 35.3) and the ED90 was estimated to be 38.5 mg (95% CI: 35.7 to 39.5). A 40 mg dose of HP provided efficient anesthesia in 46 patients (92%, 95% CI: 82 to 98). The average (SD) time to effective anesthesia was 14.5 (3.9) min. Complete sensory block at level T12 was obtained after ten minutes in 44 of 50 patients. The average (SD) duration of the sensory block was 205 (36.1) min. Maximal level of sensory block was obtained at the T8-T11 levels in 41 of 50 patients without hemodynamic instability. A Bromage 3 score was obtained in 40 of the 46 patients who achieved successful anesthesia after 30 min. Patients did not experience urinary retention, nor were any signs of transient neurologic symptoms observed. CONCLUSION: This study determined the ED50 of HP is 28.9 mg and suggests that a 40-mg dose of HP is adequate to provide successful spinal anesthesia for outpatient knee arthroscopy.