According to a recent prospective trial, compared to middle-aged patients (<50 years), what volume of local anesthetic (LA) should most likely be administered to elderly patients (>65 years) to achieve adequate anesthesia following an ultrasound-guided supraclavicular brachial plexus block?
Regional anesthesia is commonly performed to achieve surgical anesthesia, and it is well known that regional anesthesia is associated with a lower mortality rate in elderly patients. Despite this observed benefit, no studies have examined the minimum effective anesthetic volume (MEAV) of LA required to achieve surgical anesthesia in 50 percent or 95 percent of the elderly population (MEAV50 and MEAV95, respectively). From a physiologic perspective, it is known that the body changes with age and, as such, the elderly have increased sensitivity to many medications, including LAs.
Prior to initiation of this study, the authors performed a pilot study of the structure of the brachial plexus at...
