(1206) Evaluation of a Pharmacist-Driven Peripheral Opioid Antagonist Protocol in Critically Ill Patients

Introduction: Peripherally acting opioid antagonists result in inhibition of opioid-induced decreased gastrointestinal motility and delay in gastrointestinal transit time. High quality data supporting these agents in the inpatient setting is largely lacking. High frequency utilization of methylnaltrexone was reported at our institution, resulting in the creation of a pharmacist-driven protocol allowing pharmacists to order bowel regimens and restrict ordering of methylnaltrexone. The objective was to evaluate this protocol at our institution.

Methods: This was a retrospective pre- and post-intervention quality improvement project conducted at a single center large community hospital. We included adult patients over the age of 18 years admitted to an intensive care unit who received at least one dose of methylnaltrexone. In the pre-protocol cohort, 50 patients meeting inclusion criteria were randomly selected during January 2020 to December 2021. The post-protocol cohort included all patients meeting inclusion criteria from January 2023 to June 2023. We assessed receipt of bowel regimens pre-administration of methylnaltrexone and documentation of bowel movements after methylnaltrexone administration.

Results: Overall, 100 patients were included with 50 patients in the pre-protocol cohort and 50 patients in the post-protocol cohort. Patients started on an appropriate bowel regimen including two or more agents was increased from 54% pre-protocol to 80% post-protocol, p=0.011. Use of suppositories increased from 20% to 44% post-protocol, p=0.018. Administration of naloxegol post-protocol implementation increased from 0% to 26%, p< 0.001. Bowel movements within 48 hours after methylnaltrexone administration was low pre- and post-protocol implementation at 40% and 31% respectively.

Conclusions: Our results suggest improvement in the initiation of traditional bowel regimens prior to use of parenteral methylnaltrexone with this pharmacy-driven protocol. Future prospective data is warranted to further evaluate the effectiveness of peripheral opioid antagonists for suspected opioid-induced constipation in the critically ill population as compared to traditional bowel regimens.