Thread by @MichalLaurent11

Proud 🤩 to present our preprint on the use of #CO2 monitors in hospital: background, pilot data and protocol for an RCT.
A #COVID19 🧵 @trishgreenhalgh @mjb302

https://twitter.com/medrxivpreprint/status/1393260001939140609

While Belgium is about to become one of the first countries to mandate #CO2monitors in bars, no evidence supports their use, which is particularly problematic in clinical medicine #EBM. How are CO2 levels in hospitals? What does the literature say? @HuffmanLabDU @j_g_allen

Widely varying results have been reported, with values >1000 p.p.m. up to 3000 p.p.m. in low-income setttings vs. excellent values in high-resource settings
@DRTomlinsonEP @ColdProofUK @vanranstmarc @mdc_martinus @PedroFacon
sciencedirect.com/science/articl…
mdpi.com/1660-4601/17/4…

Here's another example of excessive CO2 values which are generally avoided in modern high-resource hospitals
Courtesy @Iamgoingtosleep
@realBertBlocken @CarlvKeirsbilck @CO2meetactie

https://twitter.com/novello_dr/status/1391611823628111878

In two French hospitals, maximal CO2 concentrations of 1121 to 1325 p.p.m. were reported in a hospital nursing care room and plaster room, respectively
@JeroenSchoenm @jeroenbossaert @JochenNijs @Bilulu1 @louis_ide @HarrySpoelstra @DasUlrike
sciencedirect.com/science/articl…

CO2 levels exceed limits when indoor hospital spaces are overcrowded.
In a Taiwanese intensive care unit room, CO2 levels (range 828-1570 p.p.m.) were above 1000 p.p.m. during visitor hours 92% of the year
@GMeyfroidt
ajicjournal.org/article/S0196-…

Another Taiwanese study in 3 hospitals found the worst CO2 concentration on hospital wards (AVERAGE 1063 ± 483 p.p.m.)
@YouAreLobbyLud @k_sienaert
sciencedirect.com/science/articl…

Summary: previous studies have reported widely varying indoor air CO2 levels depending on resource levels, but even in high-income countries, levels >1000 p.p.m. have been reported in hospital rooms, mainly with room overcrowding e.g. visitors
@jljcolorado @DrEricDing @EricTopol

Our RCT aims to provide clinical evidence as to whether provding CO2 monitors in hospital rooms actually improves CO2 levels @OlderTrialsProf
Now some #engineers may think: "wait a minute, isn't that logical... you ask staff to maintain CO2 <800 ppm, what's difficult about that?"

Spoiler alert: Nothing is ever easily implemented in the hospital setting, where we work with PEOPLE.
Any device or peace of equipment is useless without people changing their behavior, opening windows etc. Barriers to improve ventilation are manifold!
@drjohnmorley @wassdoc

One example can be found in our preprint Fig.3B: why do CO2 levels peak up to 1540 p.p.m. around 9 a.m.? 😬
A: Nurses come in the morning to wash two patients, toilet, dress and feed them -doors and windows closed.
Happening in every #hospital everywhere in the world, right now!

Ignorance about this remains astounding.
Most hospitals literally say "our indoor air quality is perfect"
...not based on any actual measurements however. Sometimes measurements are made in the afternoon showing 600 p.p.m., which is what we also found most of the day (Fig. 3B)

So, warning: don't come and B*S* me about how ventilation in our hospital must be awful, and ventilation in your place is perfect. That's probably based on lack of systematic measurements! Previously literature outlined above shows that levels like we found are entirely expected.

To sum up:
1. Now that the #CO2 genie is out of the bottle, it needs to move into hospital infection control.
2. This requires not only #CO2monitors but also implementation science and altering #nursing routines.
Results of our RCT to follow soon!
medrxiv.org/content/10.110…

@WarninkD @peter_persyn