“Workflow trumps Fancy Tests”

I happened to be visiting a microbiology lab in a large teaching hospital last year. We were shown all the assays they used to rapidly identify a pathogen from positive blood cultures: PCR assays, FIuorescent In-Situ Hybridisation (FISH). They had the works!

The range of tests available was very impressive, and would be the envy of most diagnostic microbiology laboratories.

But there was a catch… At 8pm in the evening, the microbiology department shut up shop and everybody went home. The blood culture analyser stood there completely untouched until 8am the next morning, including any bottles that flagged positive during this time.

So a blood culture that went positive at 9pm would be sitting in the analyser for at least 11 hours before any attempt was made to identify the pathogen.

This got me thinking!

It actually doesn’t matter that much how many fancy assays you have, or how much money your laboratory has. If you can’t get your workflow right then it all becomes a bit academic.

I am a big proponent of 24/7 staffing of microbiology laboratories, or at the very least the processing of positive blood cultures being done 24/7. It is after all one of the most important samples in the microbiology department. We have plenty of lesser importance!

Turnaround times generally don’t just include the actual analysis of the sample. More often than not, it includes storage time, transport/courier time, registration time, verification time, etc.

And then the final result has to be both received and acted on by a clinician. This communication step is also vitally important. There are so many steps, pre-analytical, analytical and post-analytical that contribute to the total turnaround time.

It is useful to do intermittent vertical timeline audits of your critical samples, to see where the delays are occurring, and then sort these out first before you consider fancy assays. And often such delays can be sorted without having to spend a lot of money. It might just be a case of relocating a blood culture analyser, or adding an extra courier run…

I am not against fancy assays, they have their place, but only as part of the whole process…


6 thoughts on ““Workflow trumps Fancy Tests”

  1. thank you for the good writing and exploring the matters which we neglect and Microbiology to be 24×7 days is better principle to make it work and continues to be difficult where the staff pattern in poor and and much worse in the developing countries the hospitals are learning just now the importance of clinical Microbiology
    thank you for innovative writing
    Dr.T.V.Rao MD Professor of Microbiology

  2. Michael,
    Do you have any good papers (or reviews) on how to do proper “vertical timeline audits of critical samples” please?
    ID & Micro, FSH & RPH
    Perth WA

    1. Hi Chris
      No!. I would think it is difficult to standardise as it very much depends on your local systems. Your LIS is always a good dtarting point but may not give you all the critical points you want to capture. Sorry for the delay in replying! Cheers, Michael

  3. Hi Michael. Love the book and the blog. I agree 24/7 workflow is highly desirable for blood cultures, but the associated staffing costs might then prevent future delivery of any fancy lab tests, even the needed ones!
    One workaround could be to get non-microbiology lab staff, who are already on overnight shifts, to at least subculture a positive blood bottle to agar plates overnight and to make a smear, but not read or report results since gram stain interpretation requires expertise and continuous maintenance of competency. At least this way the micro tech has a head start on plate incubation, and often enough growth for a “smudge” MALDI identification at 8am. I suspect most decisions on adjusting antibiotics are better left anyway until a “rapid” identification is available and the regular team is around.
    Obviously this won’t work for all hospitals e.g. those with allogenic stem cell transplant patients, but can work in non-tertiary hospitals, with clinical sepsis monitoring as the safety net overnight to catch those deteriorating patients that need antimicrobial escalation.

    1. Hi Patrick. Thanks for your comments. Sorry I am just returning to the website after a two month hiatus. Have had to prioritise other things. Agree with you, if the quality assurance is not there, then it leads to more trouble than it is worth. Best regards, Michael

Leave a Reply

Your email address will not be published. Required fields are marked *