Infrared Thermography for Assessment of Caudal Block in Children

Regional analgesia via caudal neuraxial blockade provides pain relief for pediatric patients following urological and lower extremity procedures. The injection of local anesthetic into the caudal epidural space causes a sensory loss. This sympathetic blockade in turn causes a vasodilation, or increased blood flow, to the lower extremities. The main objective of this study is to evaluate whether a significant change in distal skin temperature (measured at the feet) after caudal block placement can be detected by device users and to evaluate whether these changes can be reliably measured by users as a surrogate marker to predict presence of a caudal block.

Inclusion Criteria: * Children from 6mos to 5 years of age requiring general anesthesia and a caudal block for a surgical procedure Exclusion Criteria: * Patients with preexisting conditions that could affect the skin temperature on the lower extremities such as infection, edema, vascular disorder, etc. * American Society of Anesthesiologists comorbidity ranking of 4 or greater * Patient with contraindications for a caudal block such as: history of allergic, reactions to local anesthetics, coagulopathy, infection at the injection site, spinal abnormality, peripheral neurological disease, Raynaud's disease