Does routine pre-op testing benefit patients?
AHRQ report reveals little direct evidence
If you’ve ever had surgery, you have probably had routine preoperative testing — that is, testing everyone goes through whether or not there is reason to think they have whatever problem the test is for — of some sort. But a new study by the Agency for Healthcare Research and Quality (AHRQ) found that very few studies have been done that could answer whether ordering the same tests for everyone before surgery leads to better patient outcomes. This raises the concern that some routinely ordered preoperative tests may be a waste of time and money at best, and lead to patient harm at worst.
The comparative effectiveness report on the testing (http://www.effectivehealthcare.ahrq.gov/search-for-guides-reviews-and-reports/?pageaction=displayproduct&productid=1847), found that there is a shortage of evidence for most surgeries as to whether routine preoperative testing leads to better outcomes for patients. Elisabeth Kato, MD, MRP, an AHRQ medical officer who oversaw development of the report, says that the idea that more knowledge is better doesn’t always hold true, at least when you look at a large population.
"We went into this knowing there was not a lot of research on this," she says. "There was for cataract surgery, so we know that routine preoperative testing doesn’t do anything to reduce complications for that. But for just about everything else, there just isn’t very much — maybe one or two studies for any given test and type of surgery. There isn’t enough for us to draw any conclusions one way or the other."
All tests have potential harm — usually as minor as a needle prick, but they can also lead to a diagnostic cascade in which one test’s results lead to the need for another test, and then another and another, perhaps more and more invasive. If the tests uncover an illness that needs treating, the tests are worth it. However, a completely healthy person gets nothing from the testing but the risk. And the healthier the population you test, the more likely you are to get false positives that can set off the diagnostic cascade, Kato says.
The cost of routine preoperative testing is about $18 billion per year, which might be a bargain if we were sure they were making patients safer, but for most surgeries we don’t have data that proves that, according to Kato.
What the studies show is that for cataracts programs, it’s pretty safe to stop routine testing and only test patients whose history or exam suggest they may have a condition that could worsen if they have surgery, Kato says. For other surgical patients, there isn’t much data for routine testing that is not based on the individual patient. For hospital managers who are interested in the issue, Kato suggests, "Get people to sit down and look at your preoperative protocols and discuss the risks and benefits of them. If you have access to data on the routine testing you have done, look at it and see how often it comes back something other than normal. What happened when you had an abnormal result? How many were truly abnormal? If you can, prospectively plan a couple of protocols as a study to determine the benefits of routine preoperative testing for various surgeries. There is a serious lack of research in this area, and more good studies would be great."
For more information on this topic, contact Elisabeth Kato, MD, MRQ, Medical Officer, Agency for Healthcare Research and Quality, Rockville, MD. Telephone: (301) 427-1104.
