Minimum Effective Volume of Local Anesthetic for Shoulder Analgesia by Ultrasound-Guided Block at Root C7 With Assessment of Pulmonary Function

• DOI: 10.1097/aap.0b013e3181fa1190
• Publication Date: 2010-10-01T10:07:35Z
• Authors: Steven H. Renes; Geert J. van Geffen; Harald C. Rettig; Mathieu J. Gielen; Gert J. Scheffer
• Keywords: Ropivacaine

<h3>Background and Objectives:</h3> This study was performed to determine the minimum effective volume of ropivacaine 0.75% required produce shoulder analgesia for an ultrasound (US)-guided block at C7 root level with assessment pulmonary function. <h3>Methods:</h3> Using Dixon Massey up-and-down method design, 20 patients scheduled elective open surgery under combined general anesthesia continuous interscalene brachial plexus were included. Initial 6 mL; success or failure determined a 1-mL decrease increase subsequent patient, respectively. General standardized. A infusion 0.2% started rate mL/hr 2 hrs after completion surgery. Ventilatory function assessed using spirometry, movement hemidiaphragm by US. <h3>Results:</h3> The local anesthetic in 50% 95% 2.9 mL (95% confidence interval, 2.4-3.5 mL) 3.6 3.3-6.2 mL), hemidiaphragmatic not reduced up including surgery, but 22 start 0.2%, ventilatory significantly (<i>P</i> &lt; 0.001). <h3>Conclusions:</h3> US-guided mL, Pulmonary unchanged until 0.2%.