That strict glucose control with a continuous insulin infusion in the perioperative period would reduce hospital mortality.

16.10.2012 22:51

Objective:

Diabetes mellitus is a risk factor for death after coronary artery

bypass grafting. Its relative risk may be related to the level of perioperative

hyperglycemia. We hypothesized that strict glucose control with a continuous

insulin infusion in the perioperative period would reduce hospital mortality.

Methods: Objective: Diabetes mellitus is a risk factor for death after coronary artery
bypass grafting. Its relative risk may be related to the level of perioperative
hyperglycemia. We hypothesized that strict glucose control with a continuous
insulin infusion in the perioperative period would reduce hospital mortality.
Methods: All patients with diabetes undergoing coronary artery bypass
grafting (n  3554) were treated aggressively with either subcutaneous
insulin (1987-1991) or with continuous insulin infusion (1992-2001) for
hyperglycemia. Predicted and observed hospital mortalities were compared
with both internal and external (Society of Thoracic Surgeons 1996)
multivariable risk models.
Results: Observed mortality with continuous insulin infusion (2.5%, n 
65/2612) was significantly lower than with subcutaneous insulin (5.3%,
n  50/942, P  .0001). Likewise, glucose control was significantly better
with continuous insulin infusion (177  30 mg/dL vs 213  41 mg/dL, P  .0001).
For internal comparison, multivariable analysis showed that continuous insulin
infusion was independently protective against death (odds ratio 0.43, P  .001).
Conversely, cardiogenic shock, renal failure, reoperation, nonelective operative
status, older age, concomitant peripheral or cerebral vascular disease, decreasing
ejection fraction, unstable angina, and history of atrial fibrillation increased the risk
of death. For external comparison, observed mortality with continuous insulin
infusion was significantly less than that predicted by the model (observed/expected
ratio 0.63, P  .001). Multivariable analysis revealed that continuous insulin infusion
added an independently protective effect against death (odds ratio 0.50, P  .005)
to the constellation of risk factors in the Society of Thoracic Surgeons risk model.
Conclusion: Continuous insulin infusion eliminates the incremental increase in inhospital
mortality after coronary artery bypass grafting associated with diabetes. The
protective effect of continuous insulin infusion may stem from the effective metabolic
use of excess glucose to favorably alter pathways of myocardial adenosine triphosphate
production. Continuous insulin infusion should become the standard of care for glycometabolic
control in patients with diabetes undergoing coronary artery bypass grafting.

All patients with diabetes undergoing coronary artery bypass

grafting (n 3554) were treated aggressively with either subcutaneous

insulin (1987-1991) or with continuous insulin infusion (1992-2001) for

hyperglycemia. Predicted and observed hospital mortalities were compared

with both internal and external (Society of Thoracic Surgeons 1996)

multivariable risk models.

Results:

Observed mortality with continuous insulin infusion (2.5%, n 

65/2612) was significantly lower than with subcutaneous insulin (5.3%,n 50/942, P .0001). Likewise, glucose control was significantly better

with continuous insulin infusion (177 30 mg/dL vs 213  41 mg/dL, P .0001).

For internal comparison, multivariable analysis showed that continuous insulin

infusion was independently protective against death (odds ratio 0.43,P  .001).

Conversely, cardiogenic shock, renal failure, reoperation, nonelective operative

status, older age, concomitant peripheral or cerebral vascular disease, decreasing

ejection fraction, unstable angina, and history of atrial fibrillation increased the risk

of death. For external comparison, observed mortality with continuous insulin

infusion was significantly less than that predicted by the model (observed/expected

ratio 0.63, P .001). Multivariable analysis revealed that continuous insulin infusion

added an independently protective effect against death (odds ratio 0.50, P  .005)

to the constellation of risk factors in the Society of Thoracic Surgeons risk model.

Conclusion:

Continuous insulin infusion eliminates the incremental increase in inhospital

mortality after coronary artery bypass grafting associated with diabetes. The

protective effect of continuous insulin infusion may stem from the effective metabolic

use of excess glucose to favorably alter pathways of myocardial adenosine triphosphate

production. Continuous insulin infusion should become the standard of care for glycometabolic control in patients with diabetes undergoing coronary artery bypass grafting.