Clinical Research Directory

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.

Ropivacaine Alone Versus Ropivacaine Plus Lidocaine With or Without Epinephrine for Supraclavicular Brachial Plexus Block in Upper Limb Orthopedic Surgery

This randomized controlled trial compared three local anesthetic solutions for ultrasound-guided supraclavicular brachial plexus block in adults aged 18 to 59 years undergoing upper limb orthopedic and trauma surgery at a general hospital of the Mexican Social Security Institute (IMSS) in Aguascalientes, Mexico. Participants were randomly assigned to receive 30 mL of ropivacaine 0.375% alone, ropivacaine 0.375% plus lidocaine 1%, or ropivacaine 0.375% plus lidocaine 1% with epinephrine. The main question was whether adding lidocaine, with or without epinephrine, to ropivacaine improves postoperative analgesia. Pain intensity (0 to 10 Numeric Rating Scale) at 6 hours after surgery was the primary outcome. Secondary outcomes were pain at 0 and 12 hours, need for rescue analgesia, analgesic and opioid consumption, motor block (modified Bromage scale) and adverse events during the first 12 postoperative hours. Block onset time was also recorded.

Cerebral Oximetry During Awake Carotid Endarterectomy

Surgery to remove plaque from the carotid artery in the neck requires the artery to be clamped for a period of time. In some patients this reduces blood flow to the brain enough to cause temporary symptoms, and a temporary plastic tube called a shunt has to be inserted to restore flow. When the operation is performed with the patient awake under a local anaesthetic block, doctors decide whether a shunt is needed by talking to the patient and testing the strength of the hand on the opposite side during clamping. This is called the awake neurological test. A device called a cerebral oximeter can measure the oxygen level in the front part of the brain continuously and without needles, using light shone through the forehead. It has been suggested as a way of detecting reduced brain blood flow during this operation, and would be particularly useful for patients who are asleep under general anaesthesia and cannot be tested. However, previous studies have often chosen their alarm level after looking at their own results, and have often allowed the operating team to see the oximeter readings, which makes the results appear better than they really are. In this study, 150 adults having planned carotid surgery under a local anaesthetic block will have a cerebral oximeter attached to the forehead throughout the operation. The screen will be covered so that neither the anaesthetist nor the surgeon can see the readings, and the decision to insert a shunt will be based only on the awake neurological test, exactly as it is now. The oxygen readings will be stored inside the device and examined only after the operation. The main question is how accurately a fall of 20% or more in brain oxygen level, a level chosen in advance from previous published research, identifies the patients whose awake test becomes abnormal during clamping. The second question is whether the total amount of low brain oxygen during clamping is related to confusion or stroke in the first three days after surgery, and to memory change one month later. Participants complete a short memory test before the operation and again at one month, using different versions of the test on each occasion.