Screening Employees for Tuberculosis

In my experience, few infection control topics confuse people as much as tuberculosis screening. Except maybe the chickenpox-shingles relationship, but mostly it’s TB.  Whether it’s who gets tested after known exposure, dealing with new employees with vague histories, or BCG vaccine, it’s always something.

I’ve gone in circles for hours with staff who’ve had BCG while they insist that not only should they not be screened for TB, the BCG has given them a force field that will magically repel TB for the rest of their days on earth.  There’s little point in trying to convince them otherwise, as they will, without exception, grab another foreign-born staff member who will vehemently confirm their beliefs, and say, “See, I told you so.  This is what we were told 30 years ago in {insert name of country here}.”  For added emphasis, I’ve had doctors confirm such beliefs for them. Topic for another day.

Another side of TB screening that I’ve seen pop up on infection control message boards lately is the frequency of testing. This is determined by the TB assessment done on your facility each year.  Like any assessment, you’ll consider the population you serve, the incidence of disease in the facility and the surrounding community, protections you have in place, and anything unique. Use it to classify your facility into a risk category according to that assessment-- low-, medium-, or ongoing risk, which will determine your testing frequency.  

TB screening involves a skin test or blood test, and a risk and symptom questionnaire.  If you are a facility at medium-risk, meaning you have cases of TB regularly or serve a high-risk population, then you need to be testing your staff.  Let’s first be clear on why we screen staff for TB.

1. We test new staff on hire to identify anyone with latent or active TB coming to work at your facility  
2. We offer treatment to anyone with latent TB before it becomes active
3. We remove any staff with active TB from the premises, and get them treated so they don’t infect staff or patients
4. We identify any current staff who may have been exposed to TB during their employment, so that you can do #2 and #3 above
5. We use #4 to identify lapses in infection control

I see so many variations on testing, that it seems we’ve forgotten what it’s for.  It is to identify exposed or sick staff, get them treated, and find out where your infection control practices went wrong. If your facility sees TB patients or those at high-risk, you need to make sure you are identifying them and protecting your staff.  This is done through annual TB testing (or more often in settings with ongoing risk, like TB hospitals or clinics). Not every 2 years, not every 3.  Not with a health questionnaire on odd years, and a skin test on even years.  And certainly not by testing everyone at the same time.  

If you have a low-risk facility, where you rarely or never have or anticipate TB patients, you don’t need annual testing.  So don’t test every 2 or 3 years just to make yourself feel better, or because it seems like a good idea.  Your staff are either at risk or at no/low risk.  Testing staff who are at low risk is expensive in the time it takes, the false positives it produces, and the lack of benefit it has.  This is not how diagnostic testing is meant to be used.  It’s the opposite.

If you have determined through your assessment that staff need regular testing, you must do it an interval that is useful.  You cannot pro-rate it, depending on what Human Resources finds convenient or financially acceptable.   You cannot test your contracted or agency staff less frequently than employed staff who are doing the same jobs with the same exposure risk.  You should not do all employees during the same week. And you cannot do one-step testing when 2-step is indicated.    

If you test your staff throughout the year (either on their date of hire or birthday), and some have a conversion, you will use that valuable information.  You will see what they had in common, where they worked.  Perhaps you’ll find no relationship.  But you must arrange your system so that you have every opportunity to find the issues if they exist.

Let’s say an unknown TB patient is present on unit/ward 4West in January, and he is discharged without ever getting a correct TB diagnosis.  If I perform annual testing on all of the 4West staff in February (because we’ve elected to follow a unit-based schedule), many staff will have been exposed, unlikely any will yet test positive in February, and we won’t know about the exposure until they are tested next February, at which point it’ll be quite late to determine which patient had TB.  

Similar caveat for testing staff based on job title.  Nurses will have the highest likelihood of exposure, as they often spend the most time with the patients.  So if I test all of the hospital’s nurses in January or February, I’ll miss the exposure yet again.

However, if I test staff more randomly, by date of hire or alphabetically, I’ll be testing the 4West staff all year long, and as they start popping up positive, I may identify the issue in just 2 months time, rather than 12 months.  I’ll figure out which patient it was perhaps, identify how he went unnoticed, test the rest of the 4West staff, get them treatment if they want it, and put measures into place to prevent the next occurrence.

If I test every 2 years, I’ll never find that patient, some of my 4West staff will have moved to other jobs in parts unknown, and some may unfortunately develop active tuberculosis.  If I wait 3 years, well, what’s the point at all?

TB screening is not like insulin, where you adjust the dose depending on the blood glucose.   There isn’t “more” or “less” screening by spreading out the interval; there is one way to do it properly: testing at a useful interval, and using the health screening to improve the sensitivity and specificity of the diagnostic test.  Making unfounded adjustments alters the effectiveness significantly.

Ex-Foleyating Your Patients

I feel like I’ve talked to a dozen people about indwelling urinary catheters this week.  Sometimes a topic just keeps coming up.  So let’s review.

Doctors seem to rely on urinary output as a vital sign.*  It’s not.  If the patient is drinking and peeing, things are probably good.  If the urine is yellow, it’s good.  If you suspect retention, scan the bladder, or use a straight cath.  You could even palpate the bladder and actually physically assess the patient like they did in the old days.  Incontinence, while inconvenient, is OK.  Really.  I promise.  Very few patients need all of their urine collected and measured.  

Even dialysis patients.  A chronic dialysis patient will tell you if they make urine or not, and how often. The most accurate I&O comes from the dialysis run--it is the majority of the patient’s volume loss, and is accurately counted.  Use a less invasive method to measure the urine--bladder scan or straight catheter.  Acute renal failure?  Bladder scan to see if urine is being made.  Can I say bladder scan any more?

Indwelling catheters are only for a few select reasons (CDC, APIC)

1.      Critical illness.  When you absolutely need to count every drop in and every drop out.  This patient is in your intensive care unit, on several types of drips, unable to use a urinal or bedpan, experiencing some organ failure, or all of the above.  

There seems to be a lot of misunderstanding amongst physicians about what an “accurate” I &O is and when it is needed.   Your patient is on the telemetry/cardiac unit and is getting IV push Lasix every 8 hours.  Do you need an indwelling/Foley?  Nope.  This is a patient in mild to moderate heart failure. The diuretic will help (minus renal issues).  Your nursing staff will use a bedpan or a hat in the toilet.  If there is incontinence, they will document frequency and a semi-quantitative volume (small, medium, large).  They will monitor heart and lung sounds and edema.  The patient will or will not improve.  It doesn’t matter one bit if the output for a shift is 412mL or 523mL.   If your patient is on an intraaortic balloon pump in cardiogenic shock and can’t get to the toilet for fear of displacing the balloon, then you may have a Foley catheter. :)

2.      Immobility due to fracture.  Unstable pelvic, spinal, or hip fracture where getting on the bedpan is impossible, dangerous, or extremely painful.  Not an ankle fracture, and not a repaired hip fracture (unless ortho says so, but not until after a face-to-face talk).

3.      Non-healing perineal or sacral ulcers.   When you are desperately trying to keep a significant wound dry or a dressing in place, you can have a foley.  This is not a replacement for routine hygiene and incontinence care, or for a chapped bottom.  You do not use it as a preventive measure for skin breakdown.  You use good nursing care for that.  My son was incontinent for the first 3 years of his life. He turned out fine due to good hygiene, skin care, and frequent repositioning. :)

4.      Genitourinary or rectal surgery.  See above, for a site that must be kept dry.

5.      End of life care and comfort.   I’ve been here, personally and professionally.  By all means, the Foley.

6.      Acute urinary retention.  This is a bladder that isn’t working right now (not forever).  Usually due to meds like narcotics, anaesthesia, etc.  The plan is to get the bladder re-trained.  Take the catheter out after a few days, institute your bladder protocol (you have one, right?  No? get one.), and then bladder scan and straight cath until the bladder is working again.  Not working after a few days, then the Foley can go in and you start over.

7.      Outlet obstruction.  Physical issues of the urinary tract that don’t allow urine out: large prostate, strictures, blood clots.

If you qualify for one of these reasons, great….for today.  It’s not a season pass to the catheter club. Tomorrow you reassess all over again to see if the issue has resolved.  You should also have a nurse-driven catheter removal policy.  This is an evidence-based practice.  If the patient doesn’t meet one of those reasons, nurses can remove it.  I’ve heard docs say they didn’t know their patient had a catheter, so don’t wait on them to remove it.  My practice as a nurse was to be sure I saw every inch of my patient on first assessment.  So, sadly, it’s nursing who tells the docs their patient has a catheter.  Or a pessary.  Or that the patient’s contact lenses are still in on day 8.

And give feedback to units, nurses, and doctors.  It’s super simple to make a graph of catheter utilization, using the NHSN 50% median as your benchmark.  Is your unit doing better or worse than other similar units in the US?  And to anyone who says, “Well, our patients are much sicker/older/different”, they’re not.  You’re not special.  There are 5000 hospitals reporting into NHSN. If you are significantly worse than most, you need to improve.

After encouraging more careful assessment of catheter use at my facility last week, a nurse manager called me in a panic on Wednesday.  She said, “We have a young female patient, a new mom who was a multi trauma.  She’s trying not to use narcotics, because she’s pumping breast milk. Unfortunately she’s screaming in pain trying to get on a bedpan.  We took the catheter out yesterday and she wants it back in.  Can we?”

First, holy cow.  Bless you nurses out there on the floors.  

Second, Yes, put that thing back in.

Third, you don’t need to call me to bless your catheter placement.  Be thoughtful about it, be careful and creative to avoid use, but never forget the patient.  I know you are doing your very best.  Do those things, and don’t worry about our utilization rates, or NHSN, or anything else I tell you that you need to worry about.  If you are practicing good care, they will work themselves out.

*I hear other ICPs ask how they can get their docs on board with current guidelines. They use words like 'conservative,' and 'senior' to describe their physicians. These are euphemisms for "Out of Touch With Current Science." Don't be that doctor. As a nurse, I know nothing about Case Management. But if I need to, I'll ask the Case Management nurses. For physicians who don't know current infection control practice, ask your staff...so they don't tell all their colleagues how outdated your practices are.