Surgeons need to do more to identify patients who are taking opioids preoperatively, because this is a population that appears to be at a higher risk of worse surgical outcomes, according to a large retrospective investigation.
“Opioid users represent a potentially high-risk surgical population and may require tailored perioperative care [and] the prevalence and clinical impact of this problem in the general surgery population remain unclear,” wrote the authors of a study, led by David C. Cron, a medical student of the University of Michigan, Ann Arbor. “Given the impact of pain control and gastrointestinal function on hospital stay, it is intuitive that opioid users may have increased hospital length of stay (LOS) and may incur more costs [and] also be at higher risk for surgical complications.”
The study was published in the Annals of Surgery (2017;465[4]696-701).
Mr. Cron and his coauthors made a study cohort retrospectively from abdominopelvic surgery patients from the Michigan Surgical Quality Collaborative (MSQC) database who had surgery between 2008 and 2014. All patients were treated at the University of Michigan, and were admitted within 2 days of undergoing their operation. Any patient with data indicating use of buprenorphine prior to surgery, or those were who opioid naive before admission but received opioids after being admitted, were excluded.
Investigators found a total of 3,107 patients in the MSQC database that underwent abdominopelvic surgery at the University of Michigan during the designated time frame; from that group, 2,413 were ultimately found to match the inclusion criteria for the study. The primary outcomes were 90-day total hospital costs, along with patient LOS, and 30-day rates of complications and readmissions. Data underwent covariate risk adjustment to account for age, race, gender, body mass index, insurance class, and other factors.
“Major complications are recorded by the MSQC and include: surgical site infection, deep venous thrombosis, acute renal failure, postoperative bleeding requiring transfusion, stroke, unplanned intubation, fascial dehiscence, prolonged mechanical ventilation longer than 48 hours, myocardial infarction, pneumonia, pulmonary embolism, sepsis, vascular graft loss, and renal insufficiency,” the authors noted.
Of the 2,413 subjects overall, 502 (20.8%) were found to use opioids before surgery. Differences between opioid users and nonusers were not significant in terms of age (P = .10), gender (P = .76), and race (P = .78). After adjustment, data indicated that preoperative opioid users had 9.2% higher hospital costs than nonusers (95% confidence interval, 2.8%-15.6%, P = .005) and 12.4% longer hospital stay (95% CI, 2.3%-23.5%; P = .015). Complications and readmission rates were quantified by odds ratios, which were also found to be significantly higher in subjects who were preoperative opioid users: OR = 1.36 (95% CI, 1.04-1.78; P = .023) and OR = 1.57 (95% CI, 1.08-2.29; P = .018), respectively.
The study had some limitations, including being conducted at a single center and potentially not generalizable to other types of health care facilities and population types. Additionally, information on opioid dosage and duration of use was lacking, making it that “possible that some opioid users in our study were using opioids over a shorter time period for pain related to their surgical disease,” according to the investigators.
“These results argue the potential cost-effectiveness of intervention in this unique patient population,” Mr. Cron and his colleagues concluded. “Opioid use is a potentially modifiable risk factor, and major surgery can provide powerful leverage to improve health behavior [and] our institution has implemented a preoperative program to optimize high-risk patients for surgery.”
Mr. Cron received funding from the 2015 AOA Carolyn L. Kuckein Student Research Fellowship and the Blue Cross Blue Shield of Michigan Foundation Student Research Award for this study. He and his coauthors reported no relevant financial disclosures.