Mechanical Ventilator Weaning

This prospective observational cohort study aims to compare the predictive accuracy of diaphragmatic rapid shallow breathing index (D-RSBI) versus traditional rapid shallow breathing index (RSBI) for predicting weaning success from invasive mechanical ventilation in COPD patients. Diaphragmatic ultrasound measurements will be performed during spontaneous breathing trials, and patients will be followed for 72 hours after extubation to assess weaning outcomes.

"Weaning from mechanical ventilation is a crucial step in the intensive care unit. Several factors complicate weaning and increase the risk of failure. To predict the success of extubation, the spontaneous ventilation test (T-Tube) remains essential. Despite this, the failure rate is around 10-20%. Failed extubation is not without consequences, since it increases the risk of pneumopathy and mortality. It therefore seems essential to identify potential extubation failures using effective predictive criteria. Several of these predictive criteria have been studied separately in the literature, but are still not widely used in practice. Many studies have sought to identify these predictive criteria, without actually linking them. However, when combined in a single assessment prior to extubation, they could represent a reliable prediction and decision-making aid. In the intensive care unit at Hôpital Bichat Claude Bernard, a team of physiotherapists dedicated solely to this unit carries out a routine EPIC Assessment, combining several criteria, some of which have individually demonstrated their reliability in predicting extubation outcome. Physiotherapists are health professionals working as part of the intensive care team, and are well versed in issues relating to bronchial congestion, respiratory function and muscle strength, whether for breathing or locomotion. Similarly, their involvement in issues relating to swallowing disorders acquired in intensive care gives them an overall view of the patient's ability to protect his or her airway post-extubation. The EPIC Assessment has been designed by them to address these issues. With the help of this assessment, and by following the cut-offs of the various criteria, they link the different criteria making up the EPIC Assessment and communicate a ""favorable"" or ""unfavorable"" opinion for extubation. Our hypothesis is that the EPIC Assessment is, in addition to its interpretation by physiotherapists, a reliable tool for predicting the outcome of extubation."

The BIPER study is a stepped wedge cluster randomised clinical trial aiming to decrease extubation failure in critically-ill brain-injured patients with residual impaired consciousness using a simple clinical score.

Respiratory muscle dysfunction is highly prevalent in patients with prolonged weaning from mechanical ventilation and is strongly associated with weaning failure. Efforts to strengthen the respiratory muscles, aimed at reversing or minimizing the impact of respiratory muscle weakness on clinical outcomes, have generally focused on the diaphragm with specific inspiratory muscle training (IMT) exercises. However, the effectiveness of these exercises and impact on clinical outcomes are not current practice in the majority of ICUs, as they are hardly feasible in ICU patients who often cannot be disconnected from the ventilator and cannot fully cooperate. Promising results have been published concerning non-respiratory training techniques, which can also target the accessory muscles, particularly important in the presence of increased load to the respiratory system, as in the case of the weaning phase. These non-respiratory training techniques would have the advantage of not entailing disconnection of the patient from the ventilator. In particular, in healthy subjects, a quasi-isometric neck contraction, called neck flexion, appeared to generate greater or comparable recruitment of some principal and accessory muscles of respiration, when compared to conventional IMT. However, this has not been studied in patients requiring prolonged mechanical ventilation, for whom IMT with threshold loading devices remains the primary recommended rehabilitation strategy. Therefore, the primary aim of the investigators is to assess the feasibility, tolerability, and safety of neck flexion and to compare them with IMT technique in patients with difficult and prolonged weaning from mechanical ventilation. Secondary aims are: i) to characterize which respiratory muscles are recruited and their level of activation at different levels of ventilatory assistance and ii) to assess which respiratory muscles are recruited and their level of activation during the two techniques and to compare these findings. The hypothesis of the investigators is that neck flexion will be feasible (more than conventional IMT), well tolerated, and safe in patients with difficult and prolonged weaning. The investigators also hypothesize that, reducing the level of assistance and during unassisted breathing, a progressively increasing activation of the diaphragm, neck and trunk respiratory muscles, reflecting increased ventilatory load, will be fund. Finally, the hypothesis of the investigators is that the level of muscle activation/recruitment during neck flexion will be comparable or even greater to that occurring during IMT, as found in healthy subjects. Finding a new and highly feasible rehabilitative technique, able to recruit and train the respiratory muscles (including accessory muscles), will have the potential to promote patients' weaning and improve all related clinical outcomes, and therefore to dramatically shift the paradigm about the role of rehabilitation in ICU.