Insulin Treatment Often Needed after Surgery

A significant minority of those patients might need to take medicines for days or even weeks after they leave the hospital, to help their blood sugar levels reach a normal level again, the researchers show. Stress-induced hyperglycemia (SIH) occurs when the body reacts to the double insults of having an operation on the heart or major blood vessels, and of being cooled down by the heart-bypass machine to protect the heart muscle during surgery.

Heart and vascular surgeons already know that high blood sugar during surgery itself is associated with worse recovery and a higher risk of infection and death. So, most heart and blood vessel surgery patients currently have their blood sugars monitored while they're in the operating room, and many patients receive doses of insulin while the operation is going on.

The new study looked at what happened after surgery, and what factors predicted a need for blood sugar treatment. By far, the most telling sign that a person was likely to need such treatment was their average blood sugar two days after surgery. Those patients whose glucose levels were still high at this point were more than two and a half times more likely to need post-hospital medicines, even after other factors were considered.

Patients who had a body mass index (BMI) over 35, which is consistent with a diagnosis of obesity, were also somewhat more likely to develop SIH, as were older patients. But these factors were not nearly as strongly predictive of SIH as was the glucose level on the second day after surgery.

The patients in the study had either a coronary artery bypass operation, a heart valve operation, or an operation on the upper part of their aorta, the major blood vessel that leads out of the heart to the rest of the body.; Source: University of Michigan Health System