Intrathecal Hydromorphone and Morphine for Postcesarean Delivery Analgesia: Determination of the ED90 Using a Sequential Allocation Biased -Coin Method

摘要

BACKGROUND: Intrathecal (IT) morphine is considered the "gold standard" for analgesia after cesarean delivery under spinal anesthesia, most commonly administered at a dose of 100 to 200 pg. There is less experience with IT hydromorphone for postcesarean analgesia and limited information on its optimal analgesic dose. We conducted this study to determine the effective analgesic dose for 90% patients (ED90) of IT hydromorphone that provides effective analgesia for women undergoing elective cesarean delivery and its potency ratio to IT morphine.