Abstract :
A 16 year old male underwent right shoulder arthroscopy and Bankart procedure. The patient weighed 58 Kg and had a BMI of 19.6. He had a history of attention deficit hyperactive disorder(ADHD) treated with atomoxetine, a newer drug that works by selectively inhibiting the re-uptakeof norepinephrine (1). We planned for a general endotracheal anesthetic with interscalene blockfor postoperative analgesia. Monitors were applied in the preoperative block room including: ECG, non-invasive blood pressure, and pulse oximeter. Nasal oxygen was administered at 2 L/min. Sedation was provided with 2 mg of midazolam IV. The patient was positioned in right lateral decubitus. After sterile preparation of the skin with chlorhexidine, a high frequency US probe 12- 15 Hz (HD 11 XE, Phillips, Bothell, WA, USA) was used to localize the brachial plexus roots. A nerve stimulator was set at 0.4 mA with a frequency of 2 Hz and 0.3 ms. Skin and subcutaneous tissue anesthesia was obtained with injection of 3 ml of 1% lidocaine. Using a posterior approach, the interscalene block was performed in plane, using a 90 mm 21 guage nerve stimulator needle (Arrow, StimuQuik, Reading, PA, USA). The C6 root stimulation was confirmed with a biceps twitch, and 20 ml of 0.75% ropivacaine was injected after negative aspiration and negative test dose (D5W with 1:200,000 epinephrine, 3 ml). The C5 root stimulation was confirmed with a brisk deltoid twitch, and 20 ml of 0.75% ropivacaine was injected after negative aspiration and negative test dose. A total of 40 ml of 0.75% ropivacaine was given.
