Thursday, October 10, 2013

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.


Anonymous said...

I wish the current MD crew liked questions as much as you do. Hope the shoulder is better ... and your wife's patience is holding out. :)

I find this a really great thing. Wish the medical community did more of it. I can applaud and agree with trying to make things better, seeing if there isn't something that could be improved.

Do or do not. Try or try not. Action ... not inaction.

Skeptical Scalpel said...

Thanks. I'm feeling better today. Already 2 weeks postop.

Yes, more studies like this are needed.

Ben Rush MD said...

No worries, Skep. The next batch of studies are sure to prove the opposite to be true.

Skeptical Scalpel said...

Ben, you could be right. It would not surprise me. Thanks for commenting.

Khoi Le, M.D. said...

This is a great article. I particularly like the JAMA article re: VTE. This plays into the larger, more overarching topic of metric tracking and quality based reimbursement in my mind. Though I'm still only a surgical resident (PGY 5), as I continue my job search and knowing what questions to ask, research on these topics brings important relevant questions as to how hospitals are tracking metrics, and what their plans of action are when quality metrics aren't met. One that bothers me a lot is the looking at surgical site infection. I mean, honestly...should a surgeon get dinged when a Hinchey class IV perforated diverticulitis patient gets a wound infection? I guess it's debatable, but my initial inclination is no. But I'm biased...

Thanks for the great blog. Long time reader, first time commenter. Keep up the great work!

Skeptical Scalpel said...

Khoi, I agree about the infections. I've blogged about that before. Thanks for reading and good luck with the job hunt.

Anonymous said...

Cochran review on bowel prep for colon surgery pretty old. majority of people in my society still do it. I do it because I don't want to be admonished for not doing by older surgeons at M&M.

Skeptical Scalpel said...

Anon, good point. I could never bring myself to omit the mechanical prep. Despite the literature on the subject, I think the majority of surgeons in the US still do mechanical preps. It might be that the fear of criticism at M&M conference is a factor.

Anonymous said...


If a well-respected meta-analysis says an intervention is useless, but most clinicians do it anyways (to not look bad in M&M's), what is the point of doing studies?

Skeptical Scalpel said...

That's a good question. I read somewhere recently that it takes about 17 years for doctors to change a practice. That's almost an entire generation. It's probably true.

Anonymous said...

the point of doing studies is to get more NIH funding or to beef up your CV in hopes of landing a chairman job where your surgical productivity can decrease but your pay will increase. Another reason if non academic is to beef up your CV so you can land gigs on the speaking circuit. this is obviously a very cynical and somewhat joking answer.
I brought up the bowel prep example because I was always met with frustration as a resident when dealing with certain attendings who would bend surgical dogma to fit their practice styles. Some surgeons speak as if their means of practice is the only way to practice and as a resident you were wrong to think otherwise. common ways of expressing this would involve some stupid remark about white hair and having more of it.
another trend I read about that I found interesting and was somewhat enthusiastic about was running patients dry post op and how less tissue edema could lead to lower complications. this ran counter current to surgical dogma of urine output>30cc/hr and at various "journal clubs" was met with all kinds of "this was interesting but study wasn't relevant to my patient....etc."
I always try to remain mindful of this frustration and hope to not become the old stubborn surgeon I hated so much as a resident. I strive to be someone dynamic and at least open minded. here's another one for the road ... "no toradol on my causes bleeding!"

Skeptical Scalpel said...

Anon, I appreciate your comments.

I have expressed similar feelings about the purpose of research here

I agree with you about limiting fluids during and after surgery. It's hard to do when the anesthesiologists are not on the same page too.

I had Toradol after my recent surgery. It's good stuff and of course, doesn't cause bleeding.

Anonymous said...

u keep it unbelievably real

Anonymous said...

One of the contributing factors to perioperative over-hydration is the commonly taught idea that crystalloid replacement is 3 x amt of blood loss. The times where I have seen rapid surgical blood loss (accurately measured) and replaced with 3* crystalloid - the patients act overhydrated.

A few years ago, an ICU study found that in their population, 1.7 ml of crystalloid has the same central volume effect as 1 ml of colloid. What ratio are current surgical and anesthesiology residents being taught?

Skeptical Scalpel said...

I am not directly involved in resident teaching any longer. I agree with you that it's probably too much fluid. A quick look at the Internet shows that the 3:1 ratio is alive and well. That has been dogma for over 40 years. It's not going to disappear quickly.

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