[Effect of blood glucose control on level of lactic acid in patients with cardic-valve replacement]

To evaluate the effect of different control levels of glucose on the serum lactic acid during operation, and to investigate the relation between glucose and lactic acid to find a new way of myocardial protection.

Volunteers were divided into an experiment group(n=38) and a control group(n=33) by random sampling and double blind method. The experiment group received intensive insulin therapy and the control group received traditional therapy. The arterial blood gas samples of all the patients at different time points after the operation were harvested in the intensive care unit for blood gas analysis. The related data were collected and analyzed.

The serum glucose level in the 2 groups decreased firstly, then increased, and recovered finally. The serum lactic acid level in the 2 groups increased firstly, decreased later, then reincreased, and recovered finally. The highest level of the serum lactic acid was found 2 hours after the operation. There were significant differences in serum glucose and lactic acid levels at 2, 12, and 24 h after the operation in the two groups (P<0.01). The other data were not significant (P>0.05).

The variation of serum glucose and lactic acid level at 2, 12, 24 h after the valve replacement is consistent and significant. The serum lactic acid in the serum may be decreased by controlling the blood glucose, which provides experiment basis for myocardial protection.