Risk scale for COPD could help with hospital admissions

In an attempt to determine which patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) are at high risk for serious adverse events upon presentation to the emergency department, Canadian researchers identified 10 clinical characteristics and developed a preliminary risk scale to help standardize the admission practices of these patients.

In a prospective observational cohort study involving six teaching hospitals, 945 patients were included in the analysis based on exacerbation of COPD, a previous COPD diagnosis or a COPD diagnosis at presentation, smoking history of 15 pack-years or more, prior or current evidence of moderate airflow obstruction, and aged 50 years or older.

Of the enrolled patients, nearly 8% (n=74) had serious adverse events, and 49% (n=36) of these patients had not been admitted to the hospital at the time of first presentation to the hospital. Two of 9 deaths happened within 30 days of the initial discharge from the emergency department. The report was published online Feb. 18 for the Canadian Medical Association Journal.

“The preliminary COPD risk scale consisted of 10 elements from the history (coronary bypass graft, intervention for peripheral vascular disease, intubation for respiratory distress), examination (heart rate on arrival >110/min, post-treatment oxygen saturation <90% or heart rate >120/min) and investigations (acute ischemic changes on electrocardiography, pulmonary congestion on chest radiography, hemoglobin,100 g/L, urea >12 mmol/L, serum carbon dioxide >35 mmol/L),” said study  lead author Ian G. Stiell, MD, MSc, Department of Emergency Medicine, University of Ottawa, Ottawa, Ontario, and his colleagues.

Using a preliminary risk scale, the researchers found the range of a serious adverse event was 2.2% to 91.4%, with a score of 0 to 10, respectively.

“The 10-element preliminary COPD risk scale provides a quantitative estimate of the risk of poor outcomes,” Dr Stiell and his colleagues wrote. “We expect that this risk scale, once fully validated, will be widely used to improve both hospital admission practices and the safety of management decisions in the emergency department.”

The researchers were concerned by the number of serious adverse events that occurred after emergency department discharge. They hoped that the development of a COPD scale could improve patient safety by admitting those at highest risk for poor outcomes.

“Alternatively, the scale could be used to identify at-risk patients who should have guaranteed early follow-up, perhaps in specialized COPD clinics,” the researchers said.

The study was supported by funds from the Canadian Institutes of Health Research.