MedWire News: Among patients with chronic obstructive pulmonary disease (COPD) who develop decompensated ventilatory failure, those with hyperglycemia at baseline have the greatest risk for failure with non-invasive ventilation, research shows.
Baseline respiratory rate and hyperglycemia were also both as good as standard risk assessment tools used to predict patient outcomes, report Biswajit Chakrabarti (University Hospital Aintree, Liverpool, UK) and colleagues in the journal Thorax.
The group notes that in patients with a wide range of conditions admitted to intensive care, pretherapy hyperglycemia is an independent predictor of poor outcomes, and this might be improved by tight glycemic control.
Unknown at present, however, is the effect hyperglycemia might have on patients with respiratory failure necessitating non-invasive ventilation.
To determine whether hyperglycemia within 24 hours of admission independently predicts outcomes of non-invasive ventilation during acute decompensated ventilatory failure, the researchers studied 88 patients with COPD presenting with acute hypercapnic respiratory failure.
Random blood glucose levels were measured before non-invasive ventilation administration.
Baseline respiratory rate, random glucose levels of more than 7 mmol/l, and the Acute Physiology and Chronic Health Evaluation II (APACHE II) score were all significant predictors of worsened outcomes, such as the failure to resolve respiratory acidosis, or no need for ventilatory support for at least 48 hours.
Combining the use of respiratory rate and blood glucose levels in a risk-prediction model increased the prediction of ventilation success to 97%, while the use of all three – respiratory rate, blood glucose, and the APACHE II score – was 100% predictive.
Chakrabarti and team conclude: “In acute decompensated ventilatory failure complicating COPD, hyperglycemia upon presentation was associated with a poor outcome.”
However, they add: "Whether changes in blood glucose during therapy are as helpful remains to be studied.
"Tight glycemic control has its advocates, but careful prospective studies will be needed before this approach can be recommended in the care of patients with primary respiratory problems treated with non-invasive ventilation."
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