Inadvertent Placement of an Infraclavicular Catheter in the Interscalene Region With an Unusual Complication: A Case Report.

An infraclavicular catheter is a very efficient technique to provide excellent perioperative anesthesia/analgesia for upper limb surgery. However, complications can occur and are dependent on the technique used. We report the inadvertent placement of an infraclavicular catheter in the interscalene region when an ultrasound-guided infraclavicular catheter was threaded cranially. We proposed some strategies to avoid the occurrence of complications when performing this block.

Inflammation reduces osteoblast cytotoxicity induced by diclofenac: An in vitro study.

BACKGROUND: Diclofenac and other NSAIDs are routinely used in the postoperative period. Their effect on fracture healing remains unclear and controversial. OBJECTIVE: The primary outcome was to assess the potential cytotoxicity of clinically relevant concentrations of diclofenac on human osteoblasts. DESIGN: Laboratory in vitro study. SETTING: Institute of Physiology, Zurich, Center for Integrative Human Physiology, University of Zurich. MATERIALS: Monolayers of human osteoblasts. INTERVENTIONS: Exposure of human osteoblast monolayers to several concentrations of diclofenac, for different periods of time, with and without an artificially induced inflammatory process. MAIN OUTCOME MEASURES: Cell count, cell viability, cell proliferation and apoptosis. RESULTS: A concentration-mediated, time and exposure dependent cytotoxic effect of diclofenac-mediated apoptosis was observed. Stimulated inflammatory conditions seemed to reduce toxic effects. CONCLUSION: Cytotoxic effects of diclofenac are exposure, time and concentration dependent. Simulating aspects of inflammatory conditions seems to increase resistance to diclofenac cytotoxicity, especially in the presence of higher concentration and longer exposure time.

Dislocation rates of perineural catheters placed either perpendicular or parallel to the femoral nerve: A randomised controlled trial.

BACKGROUND: Ultrasound has increased the efficacy of femoral nerve catheters but their postoperative dislocation still remains a common problem. Although catheter placement parallel to the nerve seems to reduce dislocation rates in other nerves and plexuses, the possible advantage for femoral nerve catheter placement remains unclear. OBJECTIVE: To compare the dislocation rates of femoral catheters when placed perpendicular or parallel to the femoral nerve. DESIGN: Randomised controlled study. SETTING: University orthopaedic hospital. Duration of study: October 2018 to June 2019. PATIENTS: Eighty patients scheduled for major knee surgery with femoral catheter were enrolled and randomly allocated in two groups. Data from 78 patients could be analysed. INTERVENTIONS: The femoral nerve catheters was placed perpendicular to the nerve in Group 1 (n=40), whereas in Group 2 (n=38) parallel to it. For Group 1 the short-axis view of the nerve and an in-plane puncture was used. For Group 2 we used the short-axis view of the nerve and an out-of-plane puncture technique combined with rotation of the transducer to the long-axis view with the needle in-plane. MAIN OUTCOME MEASURES: Primary outcome was the catheter dislocation rate in the first 48 h. Secondary outcomes were pain scores and sensory blockade. RESULTS: There was no statistically significant difference between the two techniques regarding dislocation of the catheters at 24 or 48 h (at 48 h, Group 1: 15%, Group 2: 2.6%, P = 0.109). Also pain scores, sensory blockade and rescue doses of ropivacaine did not differ between the groups. However, in Group 2 the technique took longer. CONCLUSION: Rotating the ultrasound probe to the long-axis in-plane view enabled examination of the catheter position when it was placed parallel to the nerve. The parallel placement of the catheter required more time, but did not significantly improve dislocation rate, pain scores or sensory blockade. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT03693755.

Early Recognition of a Transient Ischemic Attack Utilizing Cerebral Oxygenation Monitoring During Shoulder Surgery in the Beach Chair Position: A Case Report.

Shoulder surgery in the beach chair position is routinely performed, and central neurological events are rare but potentially devastating. We present a patient with transient neurological deficits after a sudden blood pressure drop with a simultaneous decrease of regional cerebral saturation values registered by cerebral oximetry. We reviewed published cases and proposed possible strategies to prevent the occurrence of similar complications in this context.