Hyperglycaemia as a predictor of outcome during non-invasive ventilation in decompensated COPD

Chakrabarti B, Angus RM, Agarwal S, et al Hyperglycaemia as a predictor of outcome during non-invasive ventilation in decompensated COPD; Thorax 2009;64:857-862.

ABSTRACT

Rationale:

Hyperglycaemia predicts a poor outcome in Intensive Care Unit (ICU) patients. Whether this is true for respiratory failure necessitating non-invasive ventilation (NIV) is not known.

Objectives:

To determine whether hyperglycaemia within 24 h of admission independently predicts outcome of NIV during acute decompensated ventilatory failure complicating chronic obstructive pulmonary disease (COPD) exacerbations.

Methods:

Patients with COPD presenting with acute hypercapnic respiratory failure at University Hospital Aintree between June 2006 and September 2007 and receiving NIV within 24 h of admission were studied prospectively. Random blood glucose levels were measured before NIV administration.

Results:

88 patients (mean baseline pH 7.25, PaCO2 10.20 kPa, and PaO2 8.19 kPa) met the inclusion criteria, with NIV normalising arterial pH off therapy in 79 (90%). After multivariate logistic regression, the following predicted outcome: baseline respiratory rate (OR 0.91; 95% CI 0.84 to 0.99), random glucose >7 mmol/l (OR 0.07; 95% CI 0.007 to 0.63) and admission APACHE II (Acute Physiology and Chronic Health Evaluation II) score (OR 0.75; 95% CI 0.62 to 0.90). The combination of baseline respiratory rate (RR) ,30 breaths/min and random glucose ,7 mmol/l increased prediction of NIV success to 97%, whilst use of all three factors was 100% predictive. Conclusions: In acute decompensated ventilatory failure complicating COPD, hyperglycaemia upon presentation was associated with a poor outcome. Baseline RR and hyperglycaemia are as good at predicting clinical outcomes as the APACHE II score. Combining these variables increases predictive accuracy, providing a simple method of early risk stratification.

Read the paper: https://thorax.bmj.com/content/thoraxjnl/64/10/857.full.pdf