Preoperative Testing Could Be a Waste of Time and Money
Jan. 19, 2000 (Washington) -- Whether prompted by fear or good clinical
judgment, physicians routinely order billions of dollars' worth of preoperative
tests for patients, particularly for older individuals undergoing common
procedures such as cataract surgery. But those tests don't seem to matter a bit
when it comes to patient outcomes, and, according to the co-author of a study
published in the Jan. 20 issue of The New England Journal of Medicine,
they should no longer be performed.
"The statement [we] want to make is that people need preoperative
histories and physicals, but that routine testing does not produce better
outcomes," co-author James M. Tielsch, PhD, tells WebMD. He adds that the
research study was purposely designed to "provide more convincing evidence
to change practice."
The research, conducted by Oliver D. Schein, MD, MPH, Tielsch, and
colleagues from the Dana Center for Preventive Ophthalmology at the Wilmer Eye
Institute at Johns Hopkins University in Baltimore, is the first large study to
assess the clinical value of tests that are customarily ordered prior to
surgery. And although the surgery specifically examined was cataract removal, a
co-author and another prominent researcher in the field say the research is
applicable to preoperative tests for a host of other surgeries, as long as an
adequate history and physical exam are performed prior to the procedures.
"I think there is little doubt on our team that [the findings] certainly
apply to a large amount of ophthalmic surgeries," such as glaucoma surgery,
some types of retinal surgery, and most corneal surgeries, Tielsch says.
Similarly, no routine preoperative testing is necessary for surgeries in which
there is little blood loss, and when local anesthesia is used, with or without
IV sedation, says Tielsch, a professor of international health who holds joint
appointments at the Johns Hopkins schools of medicine and public health.
The investigators hope to convene meetings this spring with internists,
anesthesiologists, and surgeons to develop guidelines based on the findings.
Initially, they will concentrate on eye surgeries, he says, and likely will
address what effect different modes of anesthesiology management may have on
According to the study, the federal Health Care Financing Administration,
which runs Medicare, spends $150 million annually on routine preoperative tests
done before cataract surgery. Based on surveys with ophthalmologists,
anesthesiologists, and internists, the authors write that these preoperative
tests usually consist of complete blood counts, serum electrolyte measurements,
and electrocardiograms (ECGs). In 1996, the most recent year for which
statistics are available, some 1.5 million beneficiaries underwent cataract
surgery, which the authors describe as "the most commonly performed
operation in elderly people in developed countries."
The study compared the adverse events associated with more than 9,400
patients who had preoperative tests with the same number of patients who did
not have preoperative tests. Patients were given a letter and study brochure to
bring to their provider. Those in the no-testing group were to receive
preoperative studies only if they "presented with a new or worsening
medical problem that would warrant medication evaluation with testing, even if
surgery were not planned," write the authors. Prior to surgery, those in
the testing group were given a complete blood count, and measurements of serum
electrolytes, urea nitrogen, creatinine, and glucose were taken.