A new risk scale for chronic obstructive pulmonary disease (COPD) accurately identifies patients at high risk for serious outcomes in the emergency department, researchers from Canada report.
“The Ottawa COPD Risk Scale (OCRS) provides the attending physician with an estimate of the medical risk for these patients and the likelihood they will suffer serious outcomes,” Dr. Ian G. Stiell from Ottawa Hospital Research Institute at the University of Ottawa told Reuters Health by email. “This information can be incorporated into the overall disposition decision.”
Dr. Stiell’s team previously developed the OCRS, made up of 10 items from history, physical examination and bedside tests. The total score estimates the risk of short-term serious outcomes within 14 days, ranging from 2.2 percent for a total score of 0 to 91.4 percent for a total score of 10. The highest possible score is 16, but to date no patients have scored greater than 10.
In the current study, the team sought to validate the OCRS prospectively for its accuracy in predicting short-term serious outcomes. They enrolled 1,415 patients with exacerbation of COPD who were considered by the attending physician to be potentially well enough to be discharged from the emergency department.
Among these participants, 9.5 percent had short-term serious outcomes, including 11.0 percent of those admitted and 8.3 percent of those discharged from the emergency department.
The incidence of a short-term serious outcome in this group ranged from 4.6 percent for a total score of 0 to 100 percent for a score of 10, the researchers report in CMAJ, online December 3.
Only 51.9 percent of patients who had short-term serious outcomes were admitted at the first visit to the emergency department. Using an OCRS score of 1 or more would increase the sensitivity for identifying short-term serious outcomes by 50 percent, but would require 25 percent more admissions.
Using a threshold of 2 or more would improve sensitivity by 38 percent while increasing admission rates only slightly.
“We wish to improve the safety of COPD-patient management by decreasing the ED discharges of higher risk patients and decreasing unnecessary admissions for patients at low risk,” Dr. Stiell said. “We believe this scale can be easily used on all such patients; currently there is nothing else to provide the physicians with objective information on the risk of poor outcomes.”
Other COPD risk scales already exist. Dr. Stephen C. Bourke from Northumbria Healthcare NHS Foundation Trust, in North Shields, U.K., has previously evaluated the PEARL score for predicting readmission or death after hospitalization for acute exacerbation of COPD and the DECAF score for selecting patients for home treatment of COPD exacerbation.