Routine preanesthetic tests cost more than $60 billion every year, but far fewer than 1% reveal pertinent abnormalities relating to the anesthetic or the surgery, according to a 1989 study published in the Canadian Journal of Anesthesia (1989;36:S13-S19).
For that reason, national guidelines recommend minimizing preoperative testing in low-risk, stable patients undergoing non-emergent surgery. The American Society of Anesthesiologists (ASA) released a guideline in 2012 that advised against routine testing, such as labs, chest x-rays and electrocardiograms (EKG). But the ASA suggested a tailored approach for anything with a high risk.
Yet testing remains a common practice. Roughly half of low-risk patients still undergo unnecessary preoperative testing, according to two recent studies (Ann Surg 2012;256:518-528 and Anesth Analg 2011;112:207-212).
An interdisciplinary panel of physicians from around New York City met recently to discuss the appropriate use of pre-op testing at the New York Academy of Medicine. The session, “Why Bother! The Comprehensive Pre-Op Panel,” was organized after the American Board of Internal Medicine (ABIM) Foundation listed preoperative testing in patients undergoing routine surgery as one of five medical services of questionable value.
Preoperative testing has been an accepted part of medicine for more than 150 years since the English physician John Snow wrote about the benefit of examining his patient before administering chloroform. In the 1990s, however, doctors began to ask if these tests made any difference in outcome, and the answer was “we always did it that way,” said Elizabeth Frost, MD, clinical professor of anesthesiology at the Icahn School of Medicine at Mount Sinai, in New York City, who appeared on the panel.
“I’ve heard surgeons say that their administrator orders the tests, that the patient expects to give blood and be tested, that anesthesia will cancel the case if there are no tests, that there’s a legal liability without testing and that they have to support the hospital and labs,” Dr. Frost said.
Dr. Frost is the creator of the PreAnesthetic Assessment, a series of continuing medical education articles.
The ABIM Foundation’s “Choosing Wisely” campaign, an initiative to reduce the overuse of tests and procedures, created a guideline to help clinicians better understand and deal with the controversial medical services. The framework consists of four points: evidence of harm or little benefit, frequent misuse in practice, that it be measurable and that it be under provider control.
Preoperative testing certainly is measurable and under provider control, but many physicians are unconvinced about the other two aspects, said panelist Deborah Korenstein, MD, editor of ACP Smart Medicine, a publication of the American College of Physicians.
“There is strong evidence that pre-op testing does not change outcomes or surgery cancellation rates for patients undergoing minor procedures like cataract surgery,” Dr. Korenstein told attendees. “Studies have looked for harms that were a direct result of the tests, like bleeding and nerve damage from blood draws; and although they are rare, they are not nonexistent.”
These tests also can have non-physical consequences, such as false-positive results that trigger patient anxiety and even surgical delays, she continued.
So what do all these tests cost? A chest X-ray is $128, EKG is $216, CBC is $156, electrolytes is $626, urinalysis is $85 and a stress test is $2,300, for a grand total of $3,511, according to prices from Dr. Frost’s bill at White Plains Hospital in 2012 and the cost of a stress test at Mount Sinai.
“Pre-op lab and EKG testing should clearly be driven by history, physical and surgical risk only,” said Dr. Frost, a member of the editorial board of Anesthesiology News. “You should do a test only if it can correctly identify abnormalities, if it can change the diagnosis, or if it’s going to change the management plan or outcome. Such tests are very expensive, can cause delays and can come with unforeseen complications.”
Dr. Frost researched policies around the world and found that several other countries shared her views. Germany and Thailand are using preoperative guidelines that reduce unnecessary testing; the United Kingdom believes that there is no evidence of clinical benefit and cost-effectiveness of routine testing; and Canada supports pregnancy tests but discourages nearly all the rest.
Yet the United States has no consensus. After the ASA released its list of indications for preoperative tests, a surgeon from Texas wrote in a peer-reviewed journal that the recommendations lacked clarity, were not specific to ambulatory surgery and were not based on well-designed studies (Adv Surg 2013;47:81-98).
Panelist Tomas Heimann, MD, chief of surgery at James J. Peters VA Medical Center, in New York City, and professor of surgery at Mount Sinai, said the problem is not that preoperative testing is useless, but rather that the wrong tests are often performed.
“Our system is flawed because if a patient has an operation at Montefiore [in New York City] and is now at Mount Sinai with a complication, that information isn’t always provided,” Dr. Heimann said. “We’re doing a lot of tests now that have some usefulness, but a lot of them aren’t really making any difference. If you’re about to operate on a patient to remove his gallbladder, these routine tests aren’t going to help you. It’s critical that we’re doing tests of clinical benefit.”