Effects of target blood glucose control with insulin therapy on systolic and diastolic cardiac function in septic patients

Abstract

To explore the protective effects of target blood glucose control on cardiac dysfunction in septic patients. For this prospective and randomized interventional study, a total of 90 septic patients were divided into group A (blood glucose levels of 4.4 to 6.1 mmol/L), group B (6.1 to 8.3 mmol/L) and group C (8.3 to 10.0 mmol/L) (n = 30 each). And 30 non-septic subjects were selected into control group. Serial transthoracic echocardiogram (TTEs) was performed to measure left ventricle ejection fraction (LVEF) and ratio of blood flow velocity of mitral annulus during early diastole (E) and atrial contraction (A) before and 1, 3, 7 days after blood glucose control with insulin therapy. The plasma level of brain natriuretic peptide (BNP) was detected by enzyme-linked immunosorbent assay (ELISA). The patient records were reviewed to obtain information about demographics, Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, incidence of hypoglycemia and 28-days survival rates. No significant inter-group improvement existed in mean values of LVEFs (P = 0.184). And E/As differed among the groups and there was statistical difference between groups A and C (P = 0.005). There was a increasing trend for the levels of BNP of groups A, B and C. And comparison of group A with group B/C had statistical variability (PAB = 0.028, P(Ac) = 0.000). LVEFs had no variation (P₁= 0.310, P₃= 0.174) while E/A and BNP were significantly higher or lower in group A than those in others at Day 1 and 3 (P = 0.005). The LVEFs were similar at Day 7 and E/As and BNPs of groups A, B and C showed statistical differences. The variation of E/As with time differed between groups A, B and C. Maintaining a target blood glucose of 4.4 to 6.1 mmol/L may improve cardiac dysfunction. Furthermore, it has more significant improvement of diastolic dysfunction than systolic counterpart. Combined utilization of LVEF, E/A and BNP is better in evaluating critical ill patients with sepsis-induced cardiomyopathy under target blood glucose control. It suggests that a glucose level of 4.4 to 6.1 mmol/L may benefit cardiac consistent dysfunction in septic patients during 7 days after treatment.