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.

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.

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 2chloroprocaine 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. Universit e 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.

No abstract

No abstract