Intensive insulin therapy on infection rate, days in NICU, in-hospital mortality and neurological outcome in severe traumatic brain injury patients: A randomized controlled trial

Abstract

Objectives Evaluate the impact of an intensive insulin therapy and conventional glucose control protocol during staying in neurological intensive care unit (NICU) on infection rate, days in NICU, in-hospital mortality and long-term neurological outcome in severe traumatic brain injury (TBI) patients. Methods A total of 240 patients with severe TBI (GCS score 3–8) admitted to NICU were prospectively enrolled and randomly assigned either to conventional insulin therapy or to intensive insulin therapy. Patients in intensive glucose control group ( n = 121) received continuous insulin infusion to maintain glucose levels between 4.4 mmol/l (80 mg/dl) and 6.1 mmol/l (110 mg/dl). Patients in the conventional treatment group ( n = 119) were not given insulin unless glucose levels were greater than 11.1 mmol/l (200 mg/dl). Both groups were treated with insulin infusion to maintain normoglycemia after leaving NICU. Comparison was made against conventional insulin therapy using a randomized trial design. The primary outcomes is the mortality rate at 6 months follow-up. The second outcomes including ICU infection rate, duration of ICU stay, in-hospital mortality rate and neurologic outcome at 6 months follow-up. Results There was no significant difference in gender (66% vs. 67% male), age (46 ± 11 years vs. 45 ± 10 years), APACHE II score (30 vs. 29), TISS-28 score (47 vs. 46), and Glasgow Coma Score (GCS, 5.3 vs. 5.3) between the two groups. Overall mortality rates at 6 months follow-up were similar in the 2 groups (61 of 117, 52.1% vs. 62 of 116, 53.4%; P = 0.8). The infection rate during the study was significantly higher in patients who received conventional insulin therapy than that in patients who received intensive insulin therapy (46.2% vs. 31.4%; P < 0.05). The days stay in NICU was shorter in intensive insulin control group than that in conventional therapy group [4.2 days vs. 5.6 days (medians) P < 0.05]. The in-hospital mortality during the study was similar in conventional and intensive therapy groups (34 of 119, 28.6% vs. 35 of 121, 28.9% in the conventional and intensive insulin therapy groups; P = 0.85). The neurologic outcome according to Glasgow Outcome Score (GOS) at 6 months (GOS 5 and 4) was better in the intensive insulin therapy group (34 of 117, 29.1%) than that in the conventional therapy group (26 of 116, 22.4%, P < 0.05). Conclusions Mortality rates at 6 months follow-up are not affected by intensive glucose control in patients with severe TBI. Intensive insulin therapy decreases infection rate and days in NICU and improves the neurological outcome at 6 months follow-up, while has no obvious influence on in-hospital mortality of severe TBI patients.