ottawa_copd_risk_scale: Ottawa COPD Risk Scale

In cliot: Clinical Indices and Outcomes Tools

Ottawa COPD Risk Scale

Description

Calculates the Ottawa COPD Risk Scale score to predict the risk of short-term serious adverse events (SAEs) in patients presenting to the Emergency Department with acute exacerbation of COPD. SAEs include death, intubation, non-invasive ventilation, MI, or readmission.

Usage

ottawa_copd_risk_scale(history_copd, history_intubation, history_revascularization,
                       sa02_on_arrival, ecg_ischemia, antianginal_medication,
                       heart_rate_on_arrival, cxr_pulmonary_venous_congestion,
                       hemoglobin_on_arrival, bun_on_arrival)

Arguments

history_copd	Numeric (0 or 1). Validated only for patients with COPD.
history_intubation	Numeric (0 or 1). History of intubation for respiratory distress. (1 = Yes, +2 pts).
history_revascularization	Numeric (0 or 1). History of coronary revascularization (CABG/PCI). (1 = Yes, +1 pt).
sa02_on_arrival	Numeric. Initial oxygen saturation on arrival (%). (< 92% adds 2 pts).
ecg_ischemia	Numeric (0 or 1). Evidence of acute ischemia on ECG. (1 = Yes, +2 pts).
antianginal_medication	Numeric (0 or 1). Use of antianginal medication (e.g., nitroglycerin). (1 = Yes, +1 pt).
heart_rate_on_arrival	Numeric. Initial heart rate (bpm). (>= 110 bpm adds 2 pts).
cxr_pulmonary_venous_congestion	Numeric (0 or 1). Pulmonary venous congestion on Chest X-ray. (1 = Yes, +2 pts).
hemoglobin_on_arrival	Numeric. Hemoglobin level on arrival (g/L). (< 100 g/L adds 3 pts).
bun_on_arrival	Numeric. Urea (BUN) level on arrival (mmol/L). (> 12 mmol/L adds 1 pt).

Value

A list containing:

Ottawa_COPD_Risk_Score	The calculated total score (Range 0-16).
Risk_Short_Term_Adverse_Event	Estimated percentage probability of an adverse event within 30 days.

References

Stiell IG, Clement CM, Aaron SD, et al. Clinical characteristics associated with adverse events in patients with exacerbation of chronic obstructive pulmonary disease: a prospective cohort study. CMAJ. 2014;186(6):E193-204. doi:10.1503/cmaj.130968

Examples

# Example 1: High Risk
# Prior intubation (+2), Low SaO2 (+2), Tachycardia (+2), Low Hb (+3)
# Score = 9
ottawa_copd_risk_scale(1, 1, 0, 88, 0, 0, 120, 0, 90, 5)

# Example 2: Low Risk
# Only high BUN (+1)
# Score = 1
ottawa_copd_risk_scale(1, 0, 0, 95, 0, 0, 80, 0, 140, 15)

cliot documentation built on Dec. 1, 2025, 1:06 a.m.