Study to change how critically ill patients are treated across the world

Sydney University researchers have headed up an international study that has found that blood glucose lowering in intensive care patients increases the risk of dying by 10 per cent, indicating that international clinical practice and guidelines need urgent review.

Internationally, intensive blood glucose lowering has been widely recommended and embraced to control hyperglycaemia (high blood sugar) which is extremely common among acutely ill patients and linked with serious complications such as organ failure and death.

Local researchers were concerned with this treatment strategy and decided to conduct a large, landmark trial to confirm the best treatment for critically ill patients. These new findings reveal that international practice to intensively lower blood glucose actually increases the risk of death among intensive care unit (ICU) patients.

"Intensively lowering blood glucose in critically ill patients is not beneficial and may be harmful. Based on our findings, we do not recommend pursuing a normal blood glucose level in critically ill patients. We found that intensively lowering blood glucose levels increased a patient’s risk of dying by 10 per cent," said Chief Investigator, Professor Simon Finfer from the Faculty of Medicine and the University George Institute for International Health.

Researchers from the Australian and New Zealand Intensive Care Society Clinical Trials Group, the George Institute for International Health, the Canadian Critical Care Trials Group and Vancouver Coastal Health Research Institute set out to clarify the target range for blood glucose levels in critically ill patients. They followed 6104 ICU patients in Australia, New Zealand, Canada and the USA for up to 90 days to assess whether the treatment would improve patients chance of survival.

"Previous, smaller research studies have produced conflicting results and overall suggested that intensive blood glucose control didn’t affect death rates in critically ill adults. This new study gives us more powerful information, based on this larger study with stronger evidence, we can conclude that targeting very low levels of blood glucose is not safe," said Professor John Myburgh from the University of Sydney’s George Institute for International Health.

In Australia over 125,000 people are admitted to ICUs each year and around 7,500 patients die in Australian ICUs each year. In New Zealand, every year 17,500 people are admitted to ICUs with around 1,200 patients dying. The new evidence suggests that current guidelines must be reviewed.

"It’s essential that international guidelines reflect this new evidence. Many professional organisations recommend very tight glucose control for ICU patients – they will now need to take this new evidence into consideration and adjust recommendations accordingly," said New Zealand researcher Dr Colin McArthur, Auckland City Hospital.

Commenting on the findings, co-author and Dean of the Faculty of Medicine, Professor Bruce Robinson, said: "Running this study across a large patient group in a number of different countries has been a mammoth effort for clinicians and researchers, and Professor Finfer and colleagues should be congratulated on their achievements. In finding that clinical care guidelines need to be urgently reviewed, they have provided a clear example of how high quality research directly improves patient care."

The study, NICE-SUGAR (Normoglycaemia in Intensive Care Evaluation and Survival Using Glucose Algorithm Regulation) randomly assigned patients to one of two target ranges for blood glucose; an intensive control target (81–108mg/dL; 4.5–6.0 mmol/L) or a conventional control target (180mg/dL; 10.0 mmol/L or less). Control of blood glucose was achieved by the use of an intravenous infusion of insulin.

A unique feature of the NICE-SUGAR study was standardised complex blood glucose management, which was accessed by multiple centres as a computerised algorithm.

The results of the trial were published this week in the New England Journal of Medicine.

(Source: Sydney University: New England Journal of Medicine: April 2009)