Why make a drama out of a crisis when you can turn in into a proper opera? The particular crisis the μGnome is concerned about here is the one that sucked him into μGnostics in the early days; the one that travels under a series of guises and that is variously known as septicaemia, systemic infection, blood poisoning, bacteremia and (for the four letter acronym fanatics) SIRS.
Before the days of high-tech medicine, the doctor had to hitch up his waistcoat as he bent over the patient to feel their sweaty brow and feel their thready pulse. There was weighty certainty in his prognostications as he proclaimed an imminent fever crisis. He might not have been able to tell you what the microbial cause of the infection was (μGnosis, or ætiology) but, by golly, he could make it all sound very grim.
The difference now is that we are no longer willing to wait for diagnostic certainty if it is at the price of increasing mobidity or risk of death. Septicaemia remains a potentially fatal condition, even in the best equipped centres. The diversity of potential infective agents will keep the attending physician guessing until we have faster, more accurate decision support tools. And a series of non-infective conditions may be mistaken for sepsis.
Which brings us to critical decision points: in a previous study we discovered almost by accident that if you performed a blood culture on the day the patient arrived in hospital there was a significantly lower mortality rate than if you delayed blood culture until the next day. We interpreted this incidental observation to mean that thinking about septicaemia early in the piece probably means you do something about it like start IV antibiotics earlier. In other words, it implies that there is a critical decision point somewhere in that first few hours after hospital admission. The clever people who are working up molecular tests to tell us exactly what the μGnosis is shortly after the patient arrives with a fever aim to exploit that crisis point. None of those new methods have quite made it over the line yet, so we have to make do with the good old blood culture for the time being.
Hence the opera, and not just any opera. The one that matters is AIDA. In this case the letters are an aide memoire for
Assess (the patient)
Inoculate (the blood culture)
Decide (how to manage the patient), and
Act (to start antibiotic therapy)
Specific skills need to be mastered in the correct use of blood cultures as part of the clinical investigative repertoire. These are summarised below in a Medical Interns talk. The part that the μGnome regrets cannot be provided on-line is the practical task of performing a blood culture. That is something practitioners will have to practice themselves. Happy bug hunting.