Comparison of 0.1 and 0.05mg Intrathecal Morphine for Post-cesarean Analgesia.

The purpose of this study is to determine the ideal dose of spinal morphine for use in
Cesarean section. Spinal anesthesia (single injection in the lower back to numb patients from
the waist down) is commonly used in Cesarean section to provide numbness and pain relief
during the surgery, and adding morphine to the spinal anesthetic provides long lasting pain
relief for up to 24 hours after surgery. The ideal dose of spinal morphine, when given with
other types of pain medications such as nonsteroidal anti-inflammatories and acetaminophen,
has not been determined. In addition, spinal morphine can have side effects such as nausea
and itching, so using a lower dose of morphine may decrease these side effects while
providing the same amount of postoperative pain relief. Study participants will be divided
into two groups. Group 1 will receive the standard dose of spinal morphine (0.1mg) while
Group 2 will receive a lower dose of spinal morphine (0.05mg). Both groups will receive the
standard dose of spinal bupivacaine (numbing medication) and spinal fentanyl (short acting
pain medication). The additional pain medications (IV Toradol and oral acetaminophen) will be
given to both groups after surgery. Pain control and morphine side effects will be compared
between the two groups in order to determine the best dose of spinal morphine for cesarean
section.