Nerve blocks and chronic pain states--an update. 1. Basic considerations

Appreciation of the extremely complex nature of pain has resulted, regrettably, in diminished use of nerve blocking to manage chronic pain states. Nevertheless, clinical use of these time-honored techniques remains popular in clinical anesthesia for surgery, in obstetrics, and in the control of pathogenic pain resulting from injury or disease. Patients with chronic pain are best assessed by cross-matched analysis of medical, emotional, and social factors.