Intensive insulin therapy and indications for intensive care admission
© BioMed Central Ltd. 2007
Published: 22 March 2007
Insulin resistance and hyperglycemia are common in critically ill patients, and are associated with higher morbidity and mortality in these patients if not controlled. Intensive insulin therapy has been shown to reduce morbidity and mortality. It is not clear, however, whether the patients' indication for admission into the ICU is related to the time to achieve glycaemic control or the total dose of insulin required. This study was designed to audit the efficacy of an intensive insulin therapy protocol in achieving glycaemic control in patients presenting with different conditions.
A prospective observational study was performed over 8 weeks on patients admitted to an adult ICU who received nutrition support for up to 48 hours. Intensive insulin therapy was administered to those patients who developed hyperglycemia. The demographics, blood glucose and insulin doses were documented. Haemoglobin, white cell count, neutrophil count, antioxidants, CRP and prealbumin were measured. Outcome measures were the mean and total insulin dose and the time to achieve glycaemic control.
Forty patients, 22 (55%) males and 18 (45%) females, who received nutritional support for 48 hours or more were studied. The mean (SD) age was 59.4 (14.7) years. Enteral feeding was given in 32 (80%) and parenteral feeding in 14 (35%) patients, while six (15%) patients received both enteral and parenteral feeding. The mean (SD) energy in 48 hours was 3,307.4 (527.0) kcal, mean (SD) insulin was 1.37 (1.23) IU, mean (SD) blood glucose was 7.76 (0.9) mmol/dl and total insulin to achieve glycaemic control was 65.51 (58.6) IU. The time taken (SD) to achieve glycaemic control was 15.16 (12.65) hours. As expected, there was a relationship between the total insulin dose and the time to achieve three consecutive glycaemic controls (r = -0.43, P = 0.023). Also, between the total insulin dose and mean blood glucose r = 0.508, P = 0.001. There was no significant relationship between the total insulin dose and indication for ICU admission, and the total insulin dose and body mass index.
Findings from this study showed that the indication for admission did not affect either the total dose of insulin required to achieve glycaemic control or the time it takes to achieve three consecutive glycaemic controls.