The dawn of physiological closed-loop ventilation—a review

Abstract

The level of automation in mechanical ventilation has been steadily increasing over the last few decades. There has recently been renewed interest in physiological closed-loop control of ventilation. The development of these systems has followed a similar path to that of manual clinical ventilation, starting with ensuring optimal gas exchange and shifting to the prevention of ventilator-induced lung injury. Systems currently aim to encompass both aspects, and early commercial systems are appearing. These developments remain unknown to many clinicians and, hence, limit their adoption into the clinical environment. This review shows the evolution of the physiological closed-loop control of mechanical ventilation.

Closed-Loop Versus Conventional Mechanical Ventilation in COVID-19 ARDS

“…Closed-loop mechanical ventilation modes enable a fully automatized and optimized function of the mechanical ventilator, thus reducing the necessity for manual adjustment. 11 INTELLiVENT®-ASV is such a closed-loop ventilation mode. Based on peripheral oxygen saturation and end-tidal carbon dioxide concentration measurements, it automatically adjusts minute ventilation, the fraction of inspired oxygen (FiO 2 ) and the positive end-expiratory pressure (PEEP) breath-by-breath.…”

“…Lung-protective ventilation was defined as the combined target of tidal volume <8 ml per kg of ideal body weight, dynamic driving pressure <15 cmH 2 O, peak pressure <30 cmH 2 O, peripheral oxygen saturation !88% and dynamic mechanical power <17 J/min. Results: Forty COVID-19 ARDS patients, accounting for 1,048,630 minutes (728 days) of cumulative mechanical ventilation, allocated to either closed-loop (n ¼ 23) or conventional ventilation (n ¼ 17), presenting with a median paO 2 / FiO 2 ratio of 92 mmHg and a static compliance of 18 [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] ml/ cmH 2 O, were mechanically ventilated for 11 days and had a 28-day mortality rate of 20%. During the initial 7 days of mechanical ventilation, patients in the closed-loop group were ventilated lung-protectively for 65% of the time versus 38% in the conventional group (Odds Ratio, 1.79; 95% CI, 1.76-1.82; P < 0.001) and for 45% versus 33% of overall mechanical ventilation time (Odds Ratio, 1.22; 95% CI, 1.21-1.23; P < 0.001).…”

Scoring System to Evaluate the Performance of ICU Ventilators in the Pandemic of COVID-19: A Lung Model Study

“…The scoring system established in the present study should be able to help evaluating the performance of ventilators in a standard manner. Next generation of ventilator is toward physiological closed-loop systems ( 16 ). Decision making would be still in the hands of physicians but with the extensive physiological monitoring in current clinical environment, a physiological parameter could be accurately fed back to the controller and solve the high-stress environments as COVID-19 pandemic with a shrinking workforce ( 17 ).…”

Person-centred care during prolonged weaning from mechanical ventilation, nurses’ views: an interview study

“…In recent decades, manufacturers of ventilator equipment have developed different types of automatic weaning or closed-loop systems. These systems can reduce avoidable delays because they do not rely on healthcare professionals to make ventilator changes, which may be influenced by knowledge, decision-making and workload (Platen et al, 2020). The research area of automatic weaning is growing, but evidence for its advantages is limited; however, compared to the usual care, automated closed-loop weaning systems can reduce time on the ventilator and reduce MV in ICU patients (Rose, Schultz, et al, 2015).…”