Some venous thromboembolic events can’t be prevented even with optimal care

I have written several posts about how I get things right before others see the light, but none better than one from three years ago pointing out that some of the Centers for Medicare and Medicaid Services (CMS) "never events" can't really be completely prevented and therefore should not be considered "never events."

One specific "never event" I questioned was hospital acquired venous thromboembolic (VTE) disease which encompasses deep venous thrombosis (DVT) and/or pulmonary embolism (PE). I wrote "I am unaware of any DVT study in which no patients in the experimental arm developed DVTs or PEs. Patients will develop DVT or PE even with the best evidence-based care."

Along comes a brief research letter published last month in JAMA Surgery by a group from Johns Hopkins led by surgeon Elliott R. Haut.

Of 92 patients in their institution who had VTEs in a single year, 43 (47%) had received defect-free care. That is, each of those patients received all doses of risk-appropriate pharmacological prophylaxis ordered for the entire hospitalization.

To put it another way, VTEs for those 43 patients were not preventable. There would be no way to do a quality improvement project for a group of patients who received the right prophylaxis throughout their hospital stays and still got VTEs.

The Joint Commission/CMS criterion states that a hospital is in compliance with VTE prophylaxis if a patient receives one dose of an appropriate drug within 24 hours of admission. The Hopkins study showed that of the 49 patients (53%) whose care was suboptimal, 36 (73%) missed at least one dose of prophylaxis that was correctly ordered. Other studies have shown that missing even one dose of prophylaxis at any time during a hospitalization increases the risk of VTE.

So about half of VTEs are not preventable even with perfect adherence to the prophylaxis protocol, and the standard for compliance established by the JC/CMS is inadequate to judge the quality of an institution's performance for VTE prevention.

The study shows that 1) a lot of good information can be delivered in a two-page paper, 2) JC/CMS criteria for compliance with VTE prophylaxis need to be revisited, and 3) VTE should be removed from the list of "never events.”

What is an acceptable rate of VTE prophylaxis?

According to the paper “Hospital Performance for Pharmacologic Venous Thromboembolism Prophylaxis and Rate of Venous Thromboembolism: A Cohort Study” that appeared online in JAMA Internal Medicine last month, a rate of 70% for all eligible patients is good enough.

The retrospective study looked at rates of prophylaxis for VTE at 35 Michigan hospitals.

Of the 20,794 eligible patients included in the analysis, 1,658 either died or were transferred to higher or lower levels of care leaving 19,136 evaluable patients, 226 (1.2%) of whom suffered a VTE during either the hospitalization or the 90-day follow-up period.

Reviewing three studies that question dogma

I like studies that question accepted practices. I also like to question studies that question accepted practices. [See this post about discrediting discredited practices.]

Here are three new studies with surprising and thought-provoking results.

A few years ago, the idea of rapid response teams surfaced. These teams were supposed to be called when patients on regular floors became unstable. It was thought that such teams would be able to intervene more rapidly than simply paging the patient's physician.

Every hospital established rapid response teams, and early studies tended to confirm that they were efficacious. So all is well.

But a paper from the journal Critical Care Medicine shows that rapid response teams increase costs and intensive care unit admissions without showing any improvement in risk-adjusted patient outcomes.

Naysayers will complain that it wasn't a randomized prospective double-blind study. But it was a large before-and-after cohort study from a respected institution, the Mayo Clinic.

The authors concluded that hospitals should at least evaluate their own experiences with rapid response teams.

Another study, this time in JAMA, questions the validity of using rates of venous thromboembolic events as markers of hospital quality.

It seems the more diligently one looks for VTEs, the more one finds them. Hospitals that did more imaging studies looking for VTEs had significantly higher rates of VTE. They also had significantly higher rates of adherence to prophylaxis guidelines.

So if a patient was looking for a hospital with high quality care in the area of venous thromboembolic events, the rate of VTE might be very misleading.

A third study, also from JAMA, looked at the use of universal precautions for all ICU patients in an effort to decrease the incidence of colonization or infection by antibiotic-resistant organisms.

This was a randomized trial in 20 American ICUs, 10 of which involved health care workers donning gowns and gloves for all patient contact and 10 where gown and glove use was required only for patients with established MRSA or VRE colonization or infection. Over 26,000 patients were included.

Although the acquisition of MRSA or VRE declined from baseline in both groups, the difference was not statistically significant. [Digression. This may have been due to the famous "Hawthorne Effect," which is that behavior improves when subjects are aware that they are being watched.]

When only MRSA was looked at, a barely significant difference in acquisition was noted for the ICUs in which all personnel took precautions for all patients.

Other interesting findings were that personnel in the gown and gloves for all patients ICUs entered patient rooms significantly less frequently. The rate of occurrence of the adverse events was not different in the two groups.

To review.

Rapid response teams may not be as useful as once thought. They may lead to increased costs and ICU admissions.

Hospitals with higher rates of VTE may actually be better quality hospitals than those with lower rates.

Observing gown and glove precautions for all patients ICUs does not appear to affect the rate of acquisition of antibiotic-resistant organisms.