The human gut microbiome is truly mind-boggling. We are teaming with microorganisms and their presence has been implicated not just in C. difficile colitis but in obesity, cardiovascular disease and a whole host of other diseases. The suggestion has even been made that our genetic code should be described as not only the DNA found within our cells, but as an amalgamation of that and the genes found in the microorganisms that surround and cover us – that the microorganisms are an intrinsic part of ‘us’.
When a patient bleeds they lose whole blood, but we also see a reduction in Hb concentration. The reason for this is apparently ‘transcapillary filling’ which always sounded to me like it could be bullshit (see earlier post).
The use of positive end expiratory pressure (PEEP) when ventilating patients in critical care is pretty universal, but it’s also true that we don’t entirely know how much to use and when. The rationale for PEEP is to prevent alveolar collapse (and possibly to take some role in recruiting areas already collapsed) and improve oxygenation. The costs of PEEP however are a rise in intrathoracic pressure (with the associated haemodynamic effects) and the risk of overdistension of lung units (leading to cytokine release etc.).
The addition of Metronidazole to an antibiotic regimen is something generally done without much concern. We ‘trust’ Metronidazole to not cause resistance, and to do the job we ask of it. Why is that? I honestly can’t remember ever looking after a patient with an anaerobic infection resistant to Metronidazole.
When a doctor diagnoses atrial fibrillation, 'the guideline' says that a CHA2DS2VASc and HAS-BLED score should be calculated, and depending on the outcome an anticoagulant given. We see a lot of AF in the critical care (not as much as in CICU but that’s a different game), but we don’t follow the guidance. Or at least I don’t, but why?
The EDEN trial is one of the go-to trials for feeding in the ICU. The paper can be found here, but essentially it recruited 1000 patients with respiratory failure, comparing different calorie targets for a period of 6 days. One group received 25% of requirements (the trophic feeding group), with the other aiming for full requirements (receiving 80% of goal).* The primary outcome was ventilator free days to day 28, with the study powered to detect a 2.25 day difference. 60 day mortality was a secondary outcome.
Healthcare is a high risk and complex environment, and discussion of risk is emotive (take, for example, the headline chosen by the Times to put above a story making some effort to explain a fair blame approach).
In trying to make sense of this this complex difficult and uncomfortable area however, one of the first steps must be to quantify and describe the risk.
Unplanned admissions to critical care would seem a reasonable place to look; sampling such cases for review is an accepted method that in an ideal world all critical care units would do in co-operation with the rest of the hospital.
During my training I think I’ve been steered to think of 0.9% saline as akin to the devil, causing hyperchloraemic acidosis in all it touches – is that true?
I picked up this paper as a local news story rather than because of its content - it was written by our local neurosurgical research group. Turns out it was very interesting, but not for the reasons I thought it might be..
One of our nurses always asks me for a Nicotine patch if she’s looking after a smoker. We always have the same discussion; how the 20ml/hr of Propofol is making it unnecessary and how Nicotine patches increase mortality. In reply she always tells me we wouldn’t need 20ml/hr Propofol if I treated the Nicotine withdrawal, and to stop being so awkward, uncaring and obnoxious (the last bit is implied by the ‘look’!). To try and reassure myself I’ve dug out the paper on which I base my mortality claim. It can be found here.
This is a collection of blog posts written about new research or topics of interest.
This site is written for healthcare professionals. Nothing on it constitutes medical advice, and opinions expressed are those of the authors.
Dr Peter Hersey & Dr Laura O'Connor