Negative pressure ventilation protects the brain

Blog by Tineke (CM) van Rijn.

It was in the early lockdown Covid days, that Jan van Egmond, my colleague in music and in science, told me in one of our regular telephone calls that the old-fashioned iron lung could prevent many of the devastating effects of mechanical ventilation on the lungs. He enthusiastically spoke about the Exovent charity team and their efforts to reintroduce negative pressure ventilation. I could barely interrupt him, in a rare respiratory pause of his plea I raised the suggestion that such ventilation aid might also prevent the problems of the brain associated with anaesthesia, because patients in an iron lung don’t have to be sedated.

I had a scientist/lecturer position at the Donders Institute and the Department of Psychology of the Radboud University in Nijmegen, The Netherlands. Having a bachelor in chemistry, an MD, and a PhD in neuropharmacology, I investigated molecular mechanisms of anti-epileptic and of anaesthetic drugs. My lectures focused on functional neuroanatomy and on behavioural neuropharmacology. Back in 1998 I had learned from one of our anaesthesiologists, Herman van Beem, that he was involved in a study on effects of anaesthesia on cognitive performance. This knowledge was important for my students, many of whom would become clinical psychologists, and so will see these patients.

The paper of Hermans van Beem c.s. 1 was a landmark and in the years that followed it was confirmed by many others: anaesthesia is a risk factor to develop cognitive decline especially in the elderly 1,2. Then came Covid-19, many patients needed mechanical ventilation, and thus anaesthesia/sedation, during a long period never seen before. The reports in the newspapers were alarming and heartbreaking for elderly patients and their families: before admitting their elderly patients to the hospital, GPs asked them whether they would take the risk of coming back with cognitive problems 3,4.

The aim to reintroduce negative pressure ventilation using a modern iron lung was a message of hope for these patients and their caretakers. I incorporated this message in my next lecture, June 2020, online, so the students could learn about it: alas changes must come from the young ones.


Since I retired a year ago, I have searched the literature for papers on cognition post-ICU to learn whether invasive mechanical ventilation includes risk factors connected with cognitive dysfunction. I hypothesize that negative pressure ventilation avoids such risk factors. We posted this hypothesis in a letter to the editor of the journal Critical Care 5. In future blogs I hope to report results of this ongoing literature review.


Photo: Tineke with a colleague Joukje Oosterman (left), professor cognitive ageing. I presented a poster on the advantages of negative pressure ventilation, at our Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands on June 15, 2023.



2       Monk, TG. et al., Predictors of Cognitive Dysfunction after major Noncardiac Surgery. Anesthesioloy 2008; 108: 18-30.

3       Pinedo, D and Van der Poel R. De huisarts belt (GP calls). NRC: April 2, 2020.

4       Schildkamp, V. Gerard Spong is terug en dat is best een wonder (Gerard Spong is back and it’s quite a miracle). De Gederlander, August 13, 2022.

5       van Rijn CM, van Egmond J, Howard D, Culthard MG, Perella P, Roberts JHM, McKeown D. Negative pressure ventilation protects the brain. Crit. Care 2022; 26: Article number: 334. 

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