College of American Pathologists
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  Swapping swabs for syringes and scalpels






August 2004
Feature Story

Anne Paxton

If you have a message for hospital staff, you can’t call Western Union. Whether you want people to wash their hands, shield patient records from view, or send properly collected specimens to the laboratory, you need an awareness program. And a good catch phrase or two doesn’t hurt.

That was what Nancy Cornish, MD, director of microbiology for Omaha’s Methodist Health System, found when she recently launched an in-hospital poster campaign on specimen collection.

Her message is pithy and clear: "Swabs don’t do the job."

Dr. Cornish and other clinical microbiologists are on a mission to educate surgeons, clinicians, and nurses on why laboratory professionals need tissue or fluid—not specimens on swabs—to produce quality laboratory results. The best specimens, these laboratorians insist, are collected with metal, via scalpels, needles, and syringes.

But hammering that lesson home requires creativity and diplomacy, because misconceptions about specimen collection pervade the medical profession. "I would say microbiologists are most aware of the situation," Dr. Cornish says. "I am not sure all pathologists are. But surgeons and clinicians—many of them—just don’t realize they shouldn’t be sending swabs."

Larry D. Gray, PhD, director of clinical microbiology for TriHealth Laboratories, Cincinnati, and volunteer assistant professor at the University of Cincinnati College of Medicine, agrees that the knowledge gap is wide. "Like every other medical center, we want tissue and we want whole fluids, but many physicians, and especially surgeons, continue to send swabs of surfaces and fluids and think these are adequate specimens," he says.

There’s a routine noncompliance on the part of some surgeons, he notes. "They routinely reach over for a swab, use the swab to obtain the specimen, and that’s it. They feel that using a swab is a quick, easy, and sterile way to obtain a specimen, and they know that otherwise they’d have to cut tissue out or use a needle and syringe to aspirate fluid. They probably think they’re doing a good job."

"It’s enough of a problem that we devote a significant amount of technologist time to requesting re-collection of new specimens. It’s not the rule, but the fact that we get a recognizable number of swab specimens has always been disconcerting."

Vaginal swabs work and are adequate specimens, as are throat swabs, Dr. Cornish points out. "Sometimes we don’t find anything on the wet mount and have to set up a more sensitive method, such as cultures for yeast or Trichomonas, for example. Using DNA detection methods for gonorrhea and chlamydia of the cervix amplifies the number of organisms so we can pick them up and overcome the inadequacies of swabs."

By contrast, tuberculosis or fungus infections are harder to detect with a small amount of specimen because these organisms simply do not grow in tissues and fluids at high numbers compared with bacterial infections. "You probably won’t catch them," says Steve Dallas, PhD, director of the microbiology department at Presbyterian Health Care System, Charlotte, NC. "For most tests, we need more specimen, especially if there are multiple tests ordered."

Dr. Gray says: "If we receive a swab, we can do a gram stain and a routine aerobic culture, and maybe a routine anaerobic culture, at the most. But swabs are absolutely, without question, inadequate and nonproductive for mycobacteria and fungal cultures."

What some physicians seem to forget is that surfaces and membranes only become colonized with bacteria; it is tissue and spaces that become infected, he notes. A swab falls short as a collection device because it can sample only the surfaces and membranes, and it’s easily contaminated. But Dr. Gray has known surgeons to aspirate valuable clinical specimens, dip a swab into the specimen, and discard the rest of the valuable specimen.

At least once a day, he estimates, "we have to culture a swab with inadequate specimen and issue a disclaimer that the results will be ’equivocal.’ We usually have to give physicians some kind of result because many of the specimens can’t be re-collected. By the time we receive the specimen the patient is out of surgery and the doctor is not available, so that’s all we have to work with."

Swabs can make it difficult to detect anaerobic bacteria too. Because they live in airless places and don’t like oxygen, they tend not to grow on a swab. For example, a patient at Dr. Cornish’s hospital had a fallopian tube abscess. "They sent us a swab, and we got no bacteria to grow. They complained when they opened her up that they had drained foul-smelling pus from the site, which is usually associated with anaerobes and it should have grown bacteria.

"It was very surprising to them and they couldn’t understand it," she says. "I explained it was because they had sent me a swab, whereas if they had sent me pus I would have had a much better chance of isolating the organisms present."

The list of problems associated with swabs doesn’t end there. Another common scenario, Dr. Gray says, is when the surgeon collects a copious amount of fluid or tissue, but then takes a small amount of the specimen and puts it deep into a swab container (a tube shaped like a hollow pencil). "They use a swab to cram the small specimen down into the container and we have to fish the specimen out or cut the tube open, which is almost impossible to do without contaminating the specimen."

He tells clinicians there are only two good specimens: tissue in a large-mouth sterile container like a urine cup, and whole fluid in the original syringe or container. "My slogan is ’Send me a liter or a lobe.’"

"I’ve told several surgeons, ’You can’t send me enough pus or too much tissue or too much fluid. We want everything you can send. Send all you got.’"

Dr. Cornish has quietly lobbied clinicians and surgeons to stop using swabs for some time. But the poster campaign is new.

"I got an idea for posters, but I didn’t know how to proceed. If I were left to myself, I would have used crayons and magic markers," she confesses. Methodist’s director of pathology suggested she call the hospital public relations department. "So I did," she says, "and I worked with the audiovisual department. We put all our ideas together, gave the PR department all the agar plates and pictures of swabs and syringes, and a week later they showed up with this gorgeous, professional series of posters."

"We just put up our posters and tabletop tents, and we did educational rounds and discussions with different groups two weeks ago," Dr. Cornish told CAP TODAY in an early July interview. "I can tell you we’re already seeing fewer swabs and lots more tissue and fluids, and we’ve gotten many comments from people on the issue."

The place that the posters seemed to be most effective was inside the doors on the bathroom stalls. "We had a captive audience for the few minutes it took to read the poster, and the posters were different in each stall," she says.

In his own campaign at his four-hospital system, Dr. Dallas used a poster board with two swabs and two containers filled with Diet Coke to dramatize the benefits of fluids and tissue over swabs.

"I made a poster board with a mini-tip swab, a regular swab, a syringe, and a wide-mouth sterile cup to visually depict the differences in specimen volume. Out of curiosity, I used the swabs we distribute to surgery and measured the fluid they would absorb, and found the mini-tip swab would only hold 15 microliters of fluid, and the regular swab would only hold 150 microliters. So I filled the syringe with 1.5 milliliters of fluid—Diet Coke—and the wide-mouth sterile cup with 15 milliliters to show a 1x, 10x, 100x, 1,000x difference in specimen volume between the various specimen collection options."

The take-home message, he says, was that the mini-tip swab has 1,000 times less specimen than the container with 15 mL of fluid or tissue. "Because microbiology is a volume-dependent science, our chance of recovering pathogens is likely reduced 1,000-fold with the mini-tip swab," he adds.

At a more informal level, Dr. Gray describes going to nurses to lecture about specimen collection. When he finishes, he offers them cupcakes. When they accept, he takes a swab, sticks it in the cupcake, and hands it to them saying, "That’s a cupcake. Would you rather have a swab of a cupcake or the whole cupcake? If you get the whole cupcake, you can see what you have, but with a swab all you have is a little bit of dough or flour, which is not at all representative of the cupcake."

Illusions about specimen collection run deep. "I’ve had surgeons tell me when I started that because a nurse gave them a swab they thought it was okay to use, and I’ve had nurses tell me doctors ask for the swab," Dr. Cornish says. "Both doctors and nurses tell me they didn’t realize a swab was not an adequate method for cultures."

Dr. Dallas does in-service training to promote proper specimen collection, and he has been surprised by some of the staff’s misinformation. "I was able to get a captive audience of surgical nurses one morning a few months ago. There were more than 100 there, and I asked for a show of hands. Over half thought we actually preferred swabs."

In part, he blames the ready access to swabs, which the hospital supply service hands out freely. "The physicians know that 10 or 20 years ago it took 5 milliliters of blood just to run a blood count, where we can do a count now with only 500 microliters. And I guess they think since we’re microbiologists we can do miracles with small samples, or we can detect everything by PCR."

To get past that mistaken notion, he pegs his hopes mostly on nurses, who can stop the physician if the physician says, Hand me a swab. "The nurses are generally more receptive to CE from the laboratory than are clinicians, who pretty much assume they’ve got it all mastered." Individual physicians are a sort of moving target, Dr. Dallas says. "So with them, it’s more catch-as-catch-can."

But he’s gambling that repetition will get his message across. "It’s kind of like advertising—you just do it over and over" until the message sinks in. And while he hasn’t counted the percentage of swabs received versus fluids, he finds that, generally, the lab is getting better specimens.

At the heart of the problem is the once-over-lightly coverage that medical students get on microbiology. "We did take microbiology in medical school," Dr. Cornish recalls, "but it was classroom-taught, and it didn’t teach the practical aspects of specimen collection but about organisms and what kinds of disease they caused."

Strange as it may seem, she adds, many physicians haven’t a clue as to what goes on in the microbiology department. "They don’t realize how many plates are set up for a test, or even that we have to set up plates to grow organisms. One of our posters said, ’Do the math: An effective culture requires six plates,’ and some surgeons told me they didn’t know what the pictures of the agar plates meant."

With such a sketchy background, it’s understandable that clinicians would think of the laboratory as just a "black box," Dr. Dallas points out. "Generally, as laboratorians, we’re behind the scenes. They work with the patients and we hide behind our test tubes and petri dishes."

Dr. Cornish adds: "They’re very busy, and they don’t come up to look at the cultures; they basically look at the computer to get answers. So I think the laboratory needs to go out and educate physicians so they can use microbiology."

That’s one reason she tries to avoid rejecting specimens outright. "We set it up, but we put a comment on our report that says swabs are a suboptimal form of specimen collection, they yield false-negative results, and aspirate or tissue is preferred. I’m not sure I’d call it a disclaimer; it’s an educational statement."

If a swab is all that’s sent and there are orders for several cultures, Dr. Dallas says, "usually we ask the physician to pick one or two and say we’re not going to have sufficient volume to do the rest." He notes that his microbiology laboratory, with 20,000 tests per month, is unable to perform about 10 a month because there is not enough sample.

Unfortunately, those tend to be important cases. "The surgeons can get pretty mad, especially after they’ve already stitched the patient up. We’ve seen it happen several times with tissues—for example, an open-lung biopsy where the surgeon sends a nice biopsy to pathology, pathology sees acid-fast bacilli in their slides but microbiology only got one swab from the lung with orders for aerobic, anaerobic, tuberculosis, and fungus cultures—and guess what, nothing grew. The patient is not going to want to go through something like that again to get the right specimen."

Dr. Cornish would like to see other hospital laboratories launch campaigns to raise awareness about the deficiencies of swabs. "It would help improve the quality of results for patients and help clinicians better understand how microbiology works."

Dr. Gray says he is sympathetic to surgeons who are tempted to use swabs when operating on patients. "In their defense, it’s not easy sticking needles in people and cutting tissue out." But there’s no doubt about the bottom line, he says: "That’s how you get the best specimens."


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Anne Paxton is a writer in Seattle.