Test Details: Pseudocholinesterase (PCHE) testing has two main uses: -Monitoring for toxic exposure in people who work with organophosphate compounds by establishing a baseline PCHE activity level. Then routine testing is used to monitor for a significant reduction in PCHE activity. -Preoperative screening for patients with a history or family history of prolonged paralysis and apnea after the use of the muscle relaxant, succinylcholine, for anesthesia