Rethinking Mechanical Ventilation: Can Ventilation Mode Influence Long-Term Cognitive Outcomes in ICU Patients with COVID-19?

<b>Background:</b> Long-term cognitive impairment is common among ICU patients who required invasive mechanical ventilation (IMV). Its etiology is likely multifactorial. This preregistered study examined the association between the duration of IMV and cognitive function post-ICU, as well as the moderating effects of age and cognitive reserve. <b>Methods:</b> A secondary analysis was conducted using data from a published study of COVID-19 ICU survivors. One year after discharge, participants underwent a neuropsychological assessment. Linear regression models were used to evaluate associations between the variables. <b>Results:</b> Among patients who received IMV via endotracheal intubation, ventilation duration was not significantly associated with cognitive performance. In contrast, among tracheostomized patients, longer IMV duration was associated with better cognitive outcomes (Cohen's <i>f</i>² = 0.21). Age had a small negative main effect; in combination with IMV duration, <i>f</i>² increased to 0.31. Cognitive reserve showed a strong positive association with cognitive outcome; in combination with IMV duration, <i>f</i>² increased to 0.67. The interaction terms were negligible in both cases. <b>Conclusions:</b> We hypothesize that, compared to endotracheal intubation, IMV via tracheostoma may not only reduce the need for sedation, but also provide a more efficient respiratory support, therefore contributing to positive cognitive outcomes. However, IMV via tracheostomy still represents a form of positive pressure ventilation (PPV), which carries risks, such as ventilator-induced lung injury and reduced cardiac output and brain perfusion. These concerns about PPV, combined with our findings, indicate that alternative, non-invasive modes, such as negative pressure ventilation (NPV), warrant evaluation in future trials.