Standardizing IV Patient-Controlled Analgesia Settings Decreased Postoperative Opioid Consumption

Opioid exposure in the first 24 hours after pancreatectomy was reduced after the implementation of standardized intravenous patient-controlled analgesia (IV-PCA) settings, according to a study published in the Journal of Surgical Research.

This retrospective cohort study evaluated patient records from the University of Texas MD Anderson Cancer Center, Houston, TX. Patients who underwent a pancreatectomy and received IV-PCA treatment between 2016 and 2020 were evaluated. Patients were stratified by the period of time prior to implementing a standardized IV-PCA dosing regimen (2016-2017; n=132) and after standardization (2019-2020; n=88).

The standardized IV-PCA dosing was based on an initial limit of 1 mg oral morphine equivalent (OME) every ten minutes as needed with no basal setting and a bolus of 0.2 mg every 2 hours if needed. Patient opioid exposure was evaluated on the basis of the standardization protocol.

Pre- and post-standardization cohorts comprised patients aged mean 65 (range, 25-82) and 66 (range, 32-91) years, 45% and 43% were women, BMI was 26.24 (range, 17.8-43.9) and 25.85 (range, 17.7-36.9) kg/m², and 65.9% and 71.6% had pancreatic adenocarcinoma, respectively.

Fewer of the patients pre-standardization received open pancreatoduodenectomy (74% vs 100%; P <.001) and they were associated with longer hospital stays (median, 7 vs 5 days; P <.001).

Compliance with the standardization protocol was 92%.

IV-PCA OMEs were significantly higher among the pre-standardization patients during the first 24 hours (median, 95 vs 15 mg; P <.0001) and overall (median, 373 vs 64 mg; P <.001). Similarly, combined IV-PCA and oral OMEs were significantly higher prior to standardization (median, 525 vs 129 mg; P <.001).

Among all hospital inpatients during the study period, the proportion of opioids distributed after pancreatomy accounted for 77% of total inpatient opioid use. After implementing the standardization protocol, the proportion of opioids used by this patient population decreased to 56%.

The post-standardization cohort received more adjunct medications (mean, 3.66 vs 2.81; P <.001) and more received methocarbamol (91% vs 52%; P <.001).

Up to postoperative day 4, no significant differences in pain scores were observed between cohorts.

This study may have been limited as the post-standardization cohort received treatment during a time when the treating team put more emphasis on minimizing opioid use overall, which may have biased patient use.

In conclusion, this study found that an IV-PCA standardized protocol reduced postoperative opioid use among patients who underwent pancreatomy. The decrease in opioid use did not associate with patients reporting higher pain scores, but patients did use additional adjunct medications for pain.

Reference

Witt RG, Newhook TE, Prakash LR, et al. Association of patient controlled analgesia and total inpatient opioid use after pancreatectomy. J Surg Res. 2022;275:244-251. doi:10.1016/j.jss.2022.02.031