Patient selection: acute exacerbation of COPD with hospitalization
Outcomes: in-hospital mortality and invasive mechanical ventilation
Parameters:
(1) serum creatinine in mg/dL
(2) serum sodium in mmol/L
(3) arterial PaO2 in mm Hg
(4) arterial PaCO2 in mm Hg
(5) Glasgow coma score (GCS)
score for in-hospital mortality =
= (0.74 * (creatinine)) - (0.015 * (sodium)) + 8
score for invasive mechanical ventilation =
= (0.02 * (PaO2)) + (0.05 * (PaCO2)) - (0.47 * (GCS)) + 2.36
where:
• A higher PaO2 was associated with greater need for mechanical ventilation.
Interpretation:
• A score for mortality > 6.74 had a sensitivity of 0.71, specificity 0.64 and negative predictive value of 0.87.
• A score for mechanical ventilation > 0.54 had a sensitivity of 0.82, specificity 0.81, positive predictive value of 0.89 and negative predictive value of 0.70.
Performance:
• The area under the ROC curve was 0.73 for the mortality score.
• The area under the ROC curve is 0.85 for the ventilation score.
