Home Q&A Wiping out postop MRSA infections

Wiping out postop MRSA infections

March 2011

Published in the March 2011 issue of Today’s Hospitalist

ONE OF THE BIGGEST DEBATES raging in infection prevention is whether inpatients should be screened for MRSA “and if so, which patients and when. Finding the most effective prevention strategy has particular significance now that the Centers for Medicare and Medicaid Services may stop paying the costs of treating post-surgical infections.

At Rochester General Hospital in Rochester, N.Y., Edward E. Walsh, MD, an infectious diseases specialist, has followed that debate. He’s also watched the number of MRSA infections in his hospital’s cardiothoracic surgery patients inch up over the years.

“Almost all were sternal wound infections where staph was the most common pathogen, and about 80% of staph infections are MRSA,” Dr. Walsh says. “Our rate of infection was about 1%, which is considered reasonable in cardiac surgery “but once MRSA settles into the sternum, it’s about as hard a bug to manage as any.” Infected patients were repeatedly failing rounds of therapy, with each round consisting of weeks of vancomycin and return trips to the OR.

As studies have detailed the success rates of various tactics designed to prevent such infections, Dr. Walsh felt time and again that the solutions hospitals were trying weren’t broad enough. “You can beat people over the head to wash their hands and promote all the education you want,” he says. “The only programs that have been successful are really all-encompassing.”

In particular, he adds, programs that rely only on admission screening miss the mark because so many MRSA patients become infected after admission. That’s why Dr. Walsh, in conjunction with his hospital’s cardiothoracic surgeons, designed a series of interventions to combat hospital-acquired MRSA.

Those include nasal screening for all cardiothoracic patients one to three days before surgery, with vancomycin and cefazolin prophylaxis for those found to be carriers; nasal mupirocin for all patients, regardless of their screening status, beginning the day before surgery and continuing for five days or until discharge, if it comes first; rescreening all patients upon discharge; and using mupirocin on the site of all patients’ chest tubes when they’re removed. (When the interventions were first put in place in February 2007, all cardiothoracic staff were also screened and decolonized, if needed.)

As a result, the number of MRSA infections among cardiothoracic patients in the past four years dropped 93% and have remained steady, according to a study for online version: published in the Jan. 10, 2011, Archives of Internal Medicine. Dr. Walsh spoke with Today’s Hospitalist about the interventions and how they’ve been adapted to other surgical services.

Do guidelines endorse the kind of comprehensive program that you put in place?
The Society of Thoracic Surgeons has a large document on how to handle and prevent MRSA infections, but those guidelines target only those admissions known to be colonized with MRSA. Yet MRSA infections after surgery are not limited to those people. If you just target colonized individuals, you’ll see a 50% reduction in MRSA infections, which is nice. But why not try to do better?

Hospitals are just awash in MRSA, and patients are ex posed to the bacteria when they’re going to X-ray, seeing respiratory therapists or just sitting in a room with contaminated curtains. You have to design interventions to prevent people from picking it up while they’re here.

How much does this program cost? And did you need new staff to implement it?
We didn’t need any new staff, so we figure the program costs about $7,000 a year. We have about 800 cardiothoracic surgeries a year; the cultures cost a few dollars each, and then each patient gets a $5 tube of mupirocin.

We’ve eliminated the eight to 10 infections we used to get every year, and each of those would cost between $50,000 and $75,000 to treat. We’re probably saving on the order of $500,000 or $750,000 a year.

You write that the interventions were easy to implement because of the “long-standing use of industrial engineering methods” in how the cardiothoracic service operates. Why was that important?
That really has been key, without question. The cardiothoracic surgeons have always taken a Toyota approach, so every component of surgery and of pre- and postop care is standardized and checklisted. That’s true of glucose control, using a dedicated room and the same nurses for preop evaluations, having the same surgeons and staff, and taking all postop patients first to a cardiac ICU and then to the CT surgical floor.

The CT service took the same factory-type approach to introducing this program, which made it much easier to implement and monitor. It was so successful that we started the program two years ago with our orthopedic surgery patients, and that’s worked well.

A real problem, though, was that we have 10 orthopedic surgeons “some hospital employees, some university employees and some private practitioners. There was more grumbling along the lines of “Why should I do this? I’ve never done this before.” We had a bit more difficulty getting buy-in, but we’ve been able to get to better than 90% compliance in orthopedics.

Are you seeing the same results in those patients?
The results aren’t quite as dramatic because we weren’t starting with as many infections as in CT patients, but yes, we’ve seen a reduction. We also had to reengineer our program for orthopedic patients because they have so many more variables. Not all the surgeries are elective, as most are in CT, and orthopedic patients are first admitted to many different floors. With several groups of surgeons, we had to find a different common point to do the nasal culture and start the mupirocin. So with ortho patients, we start the program once they’ve been assigned a bed in the orthopedic unit before their surgery.

About a month ago, we introduced the program in our neurosurgery service, and we’re trying to work out the same issues. People are funneled into those surgery services in different ways than they are in CT, so it takes a while to figure out at which point in their perioperative care should the MRSA-prevention program kick in.

Are you worried about vancomycin resistance?
Not really, but we didn’t expect vancomycin resistance because we used another strategy to reduce our use of vancomycin by about 80%. In the past, we’d ask patients if they were allergic to penicillin, and if they said “yes,” we’d give them vancomycin.

Now, if they say “yes,” we follow up by asking, “What was the allergy, and can we document it?” If we can’t, they still get a beta-lactam prophylaxis, not vancomycin. When most people say they’re allergic to penicillin and you delve into the story, it’s bogus.

But mupirocin resistance may be the one Achilles’ heel that we have. If we get a clone of mupirocin-resistant MRSA in our hospital, that could unravel this whole program.

We’d have to come up with some other topical antistaph drug. So far, we haven’t seen any resistance, but we’re tracking it.

Phyllis Maguire is Executive Editor of Today’s Hospitalist.