Improving the Care of Bowel Obstruction in People with Advanced Cancer

Abstract

Background: Malignant small bowel obstruction (mSBO) is common in patients with advanced abdominal-pelvic cancers. Management includes prioritizing quality of life and avoiding surgical intervention when possible. Use of dexamethasone to restore bowel function was demonstrated in three small, randomized trials and is recommended in the National Comprehensive Cancer Network (NCCN) guidelines for mSBO. Yet, these guidelines were based upon very limited data related to effectiveness and guideline adherence is unknown in non-research settings. Furthermore, feasibility of a protocol guiding dexamethasone use for mSBO, which represents an opportunity for quality improvement (QI), has not yet been demonstrated. Methods: Project 1: Multi-center retrospective cohort study We undertook a retrospective review of unique admissions for mSBO at 6 academic medical centers (Boston Medical Center, Columbia University, Rush University, University of Iowa, University of Michigan, University of Washington) from 1/1/2019-12/31/21. Dexamethasone use and non-elective operative interventions were abstracted from the medical record and summarized with descriptive and simple comparative statistics. Multiple logistic regression analysis was used to estimate the association between dexamethasone use and likelihood of subsequent non-elective operative intervention adjusted for site, age, sex, history of abdominal surgery, nasogastric tube decompression (NGT), and Gastrografin small-bowel follow-through (SBFT). Project 2: QI initiative implementation We designed, implemented, and evaluated a protocol guiding the use of dexamethasone for mSBO. The protocol was adapted from NCCN guidelines for dexamethasone use in mSBO and incorporated into an existing protocol for small bowel obstruction management, with revision by a multi-disciplinary team including clinicians from General Surgery and Medical Oncology services. It was implemented by the Acute Care Surgery service at the University of Washington Medical Center from 3/1/2022 to 3/1/2023. Protocol adherence was evaluated using a pre-post design comparing rates of dexamethasone use and non-elective operative intervention before and after protocol implementation. Outcomes were summarized with descriptive and simple comparative statistics. Results: Project 1: Multi-center retrospective cohort study There were 571 total admissions where patients were eligible for dexamethasone during the study period (68% female, mean-age 63y, 85% history of abdominal surgery). Dexamethasone was given in 26% (150/571) of these admissions (69% female, mean-age 63y, 88% history of abdominal surgery). Dexamethasone use by site ranged from 13% (25/190 admissions) to 52% (36/69 admissions). Adjusting for site, age, sex, history of abdominal surgery, NGT, and Gastrografin SBFT use, dexamethasone use was associated with a 40% decrease in the odds of subsequent non-elective operative intervention (OR: 0.6, 95%CI 0.3-1.1). The rate of non-elective operative intervention in patients given dexamethasone during the study period was 13% (20/150 admissions) and there were 4 dexamethasone safety-related events. Project 2: QI initiative implementation Following protocol implementation, dexamethasone use increased from 13% (25/190 admissions) pre-implementation to 52% (34/66 admissions) post-implementation. Conclusions: Dexamethasone was used in about 1 in 4 eligible mSBO admissions with high variability of use between tertiary academic centers. This multi-center retrospective cohort study suggested an association between dexamethasone use and lower rates of non-elective surgery. A quality improvement initiative at a single institution demonstrated that implementing a protocol guiding the use of dexamethasone for mSBO resulted in increased use.