After baseline measurements, the investigators will insert a peripheral intravenous catheter. Then, the investigators will insert a suture-method peripheral nerve catheter (Certa CatheterTM). Procedures will be done in a sterile manner as a standard of practice. The investigators will use an ultrasound (US)-guided short-axis, needle in-plane technique. For the US-scan, the investigators will use a linear or a curvilinear transducer.