Morphine for post-caesarean section analgesia: intrathecal, epidural or intravenous?

INTRODUCTION Good analgesia is important after a caesarean section but there are no studies to date that compared intrathecal (IT), epidural (EP) and intravenous patient-controlled analgesia (IV PCA) morphine for post-caesarean section analgesia. In this study, we compared the differences in the quality of analgesia and side effects rendered by IT, EP and IV PCA morphine for post-caesarean section analgesia. METHODS We systematically collected and reviewed the data of 949 women who received IT, EP or IV PCA morphine for post-caesarean analgesia during a six-month period. We reviewed the patients 24 hours after surgery and recorded the type of analgesia, the use of adjuncts, pain scores, side effects and degree of satisfaction with the mode of analgesia. The data was captured in an electronic database and analysed. RESULTS IT morphine was the predominant method of post-caesarean analgesia, accounting for 89.5 percent of the cases. Non-steroidal anti-inflammatory drugs (NSAIDs) were more commonly used in the IT and EP group (IT 76 percent, EP 80 percent and IV PCA 49 percent, p-value is less than 0.05). IT morphine group had a significantly lower pain score at rest (p-value is less than 0.001) and on movement (p-value is less than 0.05) when compared with IV PCA group. EP morphine also resulted in a lower pain score than IV PCA on movement (p-value is less than 0.05). There was no difference in pain scores between EP and IT morphine. In the subgroup analysis of patients who did not receive NSAIDs, IT and EP morphine group also registered lower pain scores at rest and on movement than IV PCA group (p-value is less than 0.05). There was no difference in the satisfaction scores among the three groups. CONCLUSION The use of IT and EP morphine was associated with lower pain scores than IV PCA morphine at rest and on movement in the first 24 hours after caesarean section. No severe side effects were found.