Glycaemic Control in Critically Ill Adult Patients: Is intensive insulin therapy beneficial?

Abstract

OBJECTIVES Glycaemic control with intensive insulin therapy and its impact on patient outcomes have always been contentious in an intensive care setting. This study aims to assess the patterns of glycaemic control in critically ill patients at a tertiary care institution in Trinidad and its relationship to outcomes. METHODS All adult patients admitted to a multidisciplinary intensive care unit (ICU) for a period of two years were enrolled for a retrospective chart review. Data collected included demographics, admission blood glucose, mean morning blood glucose (MBG), the trend of glucose control, number of hypoglycaemic episodes, admission Simplified Acute Physiology Score (SAPS) II, ICU and hospital length of stay, duration of mechanical ventilation, anaemia, renal replacement therapy and hospital outcome. RESULTS A total of 104 patients were studied. Four different patterns of insulin therapy were practised at the ICU. The median age of patients was 55.5 years, the mean SAPS II was 49.3, the mean predicted mortality was 45.5% and the overall observed mortality was 38.5%. The majority of admissions had cardiovascular illnesses (25%), followed by sepsis (20.2%). Patients with multiple hypoglycaemic episodes had an increased mortality (p<0.01). Patients had a better outcome with a higher MBG (>100 mg/dL) (p<0.05). There was a significant difference in mortality among the four patterns of glycaemic control (p<0.001). Admission blood glucose, length of time of mechanical ventilation, ICU length of stay and renal replacement therapy were not found to be associated with adverse outcomes. CONCLUSION Intensive insulin therapy (IIT) may not benefit ICU patients but can be probably associated with higher mortality. Avoidance of hypoglycaemia as well as persistent hyperglycaemia may lead to a better outcome in critically ill patients.