Oral versus patient-controlled intravenous administration of oxycodone for pain relief after cesarean section

The optimal postoperative analgesia after cesarean section (CS) remains to be determined. The primary objective of this study was to assess whether oral oxycodone provides the same or better pain control and satisfaction with pain relief as oxycodone given intravenously using a patient-controlled analgesia (PCA) infusion device. The secondary objectives were to compare the gastrointestinal symptoms and postsurgical recovery of the two groups.

This prospective randomized trial was conducted at a University Hospital between February 2015 and June 2017. Altogether 270 CS patients were randomly assigned to receive postoperative oxycodone pain relief by IV PCA (n = 133) or orally (n = 137). Pain control and satisfaction with pain treatment were assessed by a numeric rating scale (NRS) at 2, 4, 8, and 24 h postoperatively.

No differences were found in NRS pain scores or satisfaction between the groups except at 24 h pain when coughing; there was a statistically significant difference favoring the IV PCA group (p = 0.006). In the IV PCA group, the patients experienced more nausea at 4 h (p = 0.001) and more vomiting at 8 h (p = 0.010). Otherwise, postoperative recovery was similar in both groups. The equianalgesic dose of oxycodone was significantly smaller in the oral group (p = 0.003).

This study indicates that oral oxycodone provides pain control and satisfaction with pain relief equal to IV oxycodone PCA for postoperative analgesia after cesarean section. Satisfaction with pain treatment was high in both groups, and both methods were well tolerated. Early nausea was less common with oral medication.