The long-held belief that patients with diabetes have a markedly worse perioperative outcome after vascular surgery, compared with patients with normal sugar metabolism steadily crumbled during the 1990s.
A recent success story for vascular surgery in diabetes was a report from surgeons at Beth Israel Deaconess Medical Center in Boston. Those investigators reported their experience during 1990-2000 treating more than 3,100 patients with diabetes and almost 2,000 patients without diabetes.
In this series, the perioperative rates of death, myocardial infarction, and congestive heart failure were essentially identical for patients regardless of whether or not they had diabetes.
The total incidence of these three end points was just under 4% for the entire patient population (Arch. Surg. 137[4]:417-21, 2002).
“The prevailing view among vascular surgeons is to offer corrective, vascular surgery to patients with diabetes,” commented Dr. James Menzoian, who is chief of vascular surgery at Boston Medical Center. “Some physicians hold onto the old view, that surgery is too dangerous for patients with diabetes, but they need to get with it. Modern series clearly show that surgery is safe.”
One limitation of the Beth Israel Deaconess report was that as a retrospectively reviewed series, it relied on clinical diagnoses of myocardial infarction or heart failure. Patients were not followed by serial ECGs or measurement of cardiac enzymes, which are more sensitive gauges of the incidence of cardiovascular disease end points. “There is no question that we underestimated the incidence of myocardial infarction and heart failure in all of our patients,” said Dr. Allen D. Hamdan, who is a vascular surgeon at Beth Israel Deaconess and lead investigator for the study.
Dr. Hamdan attributed his group's success in this series to several aspects of the care that patients received:
Careful
fluid management, with aggressive use of Swan-Ganz catheters.A
dedicated step-down unit staffed with nurses experienced in caring for patients
who have undergone vascular surgery.Aggressive
management of the patients with diabetes, usually by a physician from the Joslin
Diabetes Center in Boston, where many of the patients with diabetes in the
series received their care before and after their surgery.But these features are not unique to this series, according to Dr. Menzoian. Patients can get similar care at many places.” The results are probably generalizable as long as other centers follow similar procedures, he said.
But a key factor is that physicians managing these patients must be aware of a patient's diabetes and then take the appropriate steps.
“I agree that diabetes is not a factor that should prohibit vascular surgery, but these patients face risks and steps must be taken to reduce their risks,” commented Dr. Lee A. Fleisher, vice chairman of anesthesiology at Johns Hopkins University in Baltimore.
This means assessing the patients for occult coronary artery disease before surgery, possibly with a stress test, and treating the patient with a
-blocker.
These drugs have been clearly shown to reduce operative risk in all patients
with underlying vascular disease, Dr. Fleisher said.Although the perioperative outcomes of patients with diabetes are good, the Beth Israel Deaconess report also showed that their long-term prognosis is poor. During 5 years of follow-up, patients with diabetes had about a 50% mortality rate, compared with about a 25% rate among the other patients in the series.
Although the review was unable to show why patients with diabetes did worse over the long term, “my guess is that surgery is probably not affecting their long term survival,” said Dr. Hamdan. We know that patients with diabetes tend to have worse long-term survival. We have not yet figured out what we need to do to help keep these patients alive."