Functional Status Can Predict Success in Lower Extremity Revascularization

Newswise — A new study of 5,600 patients undergoing open lower extremity bypass operations, examines the validity of a single preoperative functional status determination, and its ability to predict major morbidity and mortality for patients undergoing open lower extremity bypass operations. It was presented today at the 63rd Annual Meeting(R) of the Society for Vascular Surgery(R).

Peripheral arterial disease (PAD) affects about 8 to 10 million Americans. It is more common as one gets older, and in people who diabetes, high cholesterol, and smokers. According to the Society for Vascular Surgery by age 70, one in three individuals is affected by it.

Common initial complaints include the inability to walk long distances because of pain in the lower extremities. Patients report that they have to stop walking after a few blocks because of cramping, especially in the calf area (claudication). As the condition progresses, patients can experience a more severe form of the disease, where pain is present even when the patients are not ambulating (rest pain). Rest pain tends to be worse at night and when patients are lying flat in their beds. Without treatment, PAD can progress to tissue loss, ulceration, gangrene, and amputation of the limb.

There are new pharmacological therapies to fight high cholesterol and diabetes, and there has been an intense public campaign against smoking. But, it has been the emergence of minimally invasive endovascular surgery, which has greatly expanded the treatment options for patients with severe PAD, much the same way that angioplasty and stenting expanded treatment options for patients with coronary artery disease.

Despite these advancements, certain patients still require traditional open lower extremity vascular surgery in order to relieve life limiting symptoms or to save their extremities from an amputation. The decision to undergo a complex, lower extremity bypass operation is not a simple one. Both doctors and patients must weigh the benefits against the many potential risks associated with the procedure.

Robert S. Crawford, MD, vascular and endovascular fellow at Massachusetts General Hospital and Harvard Medical School in Boston, reported that he and other authors from the institution divided patients into either functionally independent versus functionally dependent status, based on their ability to perform simple activities of daily living (ADL).

"Activities of daily living (ADLs) include routine activities that people do everyday without needing assistance. Eating, bathing, dressing, toileting, transferring (walking), and continence are the six basic ADLs," said Dr. Crawford. "Our results showed that the identification of dependent preoperative functional status independently predicts negative postoperative outcomes in patients undergoing lower extremity bypass operations. Specifically, functional dependency predicted an increase in the incidence of major systemic and major operative site complications, as well as minor complications and death."

Dr. Crawford noted that the successive addition of relevant variables such as the need for hemodialysis (removal of waste from the blood for a patient with previous kidney renal failure), emergency surgery and age (those 80 years or older), increased the chances of dying while undergoing a lower extremity bypass operation by 13-, 38- and 97-times, respectively. Similarly, the risk of major systemic complications can increase 68 times if a functionally dependent patient has been on a ventilator before the operation, is 80 years of age or older and is operated on as an emergency.

"The simple determination of dependent functional status is a sensitive predictor of all major postoperative outcomes," added Dr. Crawford. "When combined when other relevant variables it can identify patients that may be unsuitable to undergo lower extremity bypass operations because of prohibitive postoperative morbidity and mortality. This information can be used by physicians trying to help patients and their families make appropriate decisions regarding the decision to undergo a major operation."

Information about patient cases came from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. The ACS-NSQIP data comes from a consortium of academic and community hospitals, and collects preoperative as well as 30-day morbidity and mortality outcomes for patients undergoing major surgical procedures. The ADL determination was performed independently by a research nurse member of the NSQIP prior to the operation.

About the Society for Vascular Surgery®The Society for Vascular Surgery (SVS) is a not-for-profit society that seeks to advance excellence and innovation in vascular health through education, advocacy, research and public awareness. SVS is the national advocate for 2,800 vascular surgeons dedicated to the prevention and cure of vascular disease. Visit the web site at www.VascularWeb.org® or you can follow SVS on Twitter by searching for VascularHealth or at http://twitter.com/VascularHealth.