Oral vs IV Acetaminophen in Preoperative Multimodality Pain Management: Are They Equal?

A retrospective analysis showed that short-term postoperative opioid consumption was not affected by the acetaminophen formulation used in a multimodality perioperative pain management regimen in patients undergoing open surgery for gynecologic cancers. These findings were reported in Gynecologic Oncology.¹

A reduction in postoperative pain as a means to limit opioid consumption following surgery is a key element of an enhanced recovery after surgery (ERAS) program. Hence, ERAS guidelines recommend preoperative administration of a combination of different classes of pharmacologic agents with distinct analgesic mechanisms of action, such as acetaminophen, a nonsteroidal anti-inflammatory drug, and a gabapentinoid.²

Although acetaminophen can be administered as part of a multimodality, perioperative pain management regimen using either the oral or IV route, the cost of a comparable dose of IV acetaminophen has been estimated to be approximately 600-fold higher than oral acetaminophen.¹

This analysis involved consecutive patients undergoing open gynecologic oncology surgery at the University of Texas MD Anderson Cancer Center in Houston, Texas. Patients received either preoperative IV acetaminophen between May 1, 2016, and February 28, 2017, or oral acetaminophen between May 1, 2017, and February 28, 2018, along with the other components of multimodal perioperative pain management, which included pregabalin, celecoxib, and tramadol extended release.

The primary outcome measure was total daily postoperative opioid consumption on postoperative days 0 and 1.

Of the 353 patients included in the analysis, 178 and 175 received preoperative acetaminophen in the IV and oral form, respectively. No significant differences between the 2 patient subgroups with respect to median patient age, median comorbidity score, median time in PACU, and median body mass index were observed. However, a matched-pair analysis was performed to compensate for differences in surgical time, general anesthesia method, and intraoperative dose of dexamethasone observed between those receiving IV vs oral acetaminophen, as well as other potential confounders.

The matched-pair analysis found no significant differences between the 2 subgroups with respect to the amount of opioids consumed on postoperative days 0 (P =.56) and 1 (P =.38).

“The significantly higher cost associated with the preoperative IV acetaminophen formulation and the lack of clinical benefit favors the use of oral acetaminophen when possible,” the study investigators stated in their concluding remarks.

Disclosures: One author declared receiving support through a National Institutes of Health grant. Please see the original article for a full list of disclosures.

References

1. Cain KE, Iniesta MD, Fellman BM, et al. Effect of preoperative intravenous vs oral acetaminophen on postoperative opioid consumption in an enhanced recovery after surgery (ERAS) program in patients undergoing open gynecologic oncology surgery. Gynecol Oncol. Published online December 6, 2020.  doi:10.1016/j.ygyno.2020.11.024

2. Beverly A, Kaye AD, Ljungqvist O, Urman RD, et al. Essential elements of multimodal analgesia in Enhanced Recovery After Surgery (ERAS) guidelines.Anesthesiol Clin. 2017;35(2):e115-e143. doi:10.1016/j.anclin.2017.01.018