Seek And Ye Shall Find
Quality is very difficult to measure in healthcare. As I have said many times before, measures of quality tend to be things that can be easily quantified and put in a checklist. Whether or not these indices have anything to do with actual quality does not seem to matter to the Center for Medicare and Medicaid Services (CMS). One such measure, incidence of venous thromboembolism, has been called into question, most recently in Anesthesiology News, in which Christina Frangou reports on a study recently presented at the American Surgical Association annual meeting. Here’s Frangou quoting Dr. Mila Ju, one of the studies authors:
“Hospital may be unfairly deemed a poor performer for the outcome VTE measure if they have increased vigilance for VTE by performing more VTE imaging studies.”
If you look for it, you’re more likely to find it.
VTE is medical-speak for a blood clot in a vein, usually a large vein, often in the lower leg. These clots can occur for many reasons, but venous stasis caused by prolonged bedrest or immobility is one reason. Patients having hip surgery, for example, might be immobile for enough time for blood clots to form. The problem with these clots is that, in rare cases, they detach and float through the venous system to the lungs, causing a blockage of blood flow to a lung or part of a lung, causing oxygenation problems or even death. Most of the time they don’t. In many post-operative cases VTE is preventable using blood thinners such as Heparin, or devices that compress the muscles of the legs, like Venodyne boots. CMS has deemed the incidence of VTE to be a quality measure, that is, VTE in post-surgical patients should never occur because it is preventable. Medicare will not reimburse for the care of post-surgical VTE and starting in 2015 VTE occurrence will be tied to financial penalties. CMS apparently has a zero-tolerance policy on VTE.
Now, no one can argue that preventing preventable complications is quality care. There are several problems with using VTE as a quality measure, however. Problem number one is that VTE is actually pretty rare, in the 1% range, which limits it’s validity as a basic quality measure. Second problem is that to document the occurrence of VTE, you have to do a venous ultrasound or other imaging study. With a 1% incidence, there’s a lot of extra imaging going on that wouldn’t occur without the mandate to document. In fact, hospitals with higher rates of VTE also performed more imaging studies. Not only that, but the hospitals that did more imaging studies for VTE had also adhered most strictly to prophylaxis guidelines, even though a study in the Annals of Surgery in 2011 found that VTE rates failed to improve after implementation of guidelines that called for more aggressive pharmacologic prophylaxis. Translated, that means blood thinners don’t always work. Compression boots don’t always work, especially if applied incorrectly, something you can’t measure with a check box. Also, blood thinners come with their own risks, leading to complications potentially worse than VTE.
Maybe rate of VTE incidence really is a good quality measure. Maybe some patients get heparin and compression boots and early mobilization and aggressive PT and some don’t. But its also a terrible measure because it aggressive prophylaxis doesn’t always work. It doesn’t matter what you do, some patients are going to get VTE no matter how good the care is. It’s a terrible measure because all the care in the world won’t prevent VTE if the compression boots are hanging off the end of the bed because the patient won’t wear them. It’s a terrible measure because going looking for a problem usually ends in finding one.
Here’s Dr. Sam Finlayson, chair of surgery at the University of Utah:
“The problems that the authors [of Ju’s study] have uncovered related to VTE rates strengthen the argument of those who believe that outcome-based, pay-for-performance programs are not ready for prime time.”