Intermittent Suctioning for Patients Under Artificial Ventilation: A Digital Model Study

Endotracheal Suctioning is a clinical resource commonly used for the bronchial hygiene of patients under artificial ventilation. This work aims to propose a new procedure to avoid damage to the patient during this process. Considering the importance of assessing the impact of the mechanical ventilation-suctioning interaction on the respiratory system, one of the objectives of this work is to validate a computational model of a closed tracheal suctioning system. For that, the pressures, obtained by the model, were compared to those resulting from aspiration in a physical lung model. Combinations of catheter and orotracheal tube sizes, as well as ventilatory and suctioning pressures, were used. The difference between the alveolar pressures obtained with the computational and physical models was not greater than 0.3 cmH₂O; with the correlation between the signals higher than 0.999. Therefore, the computational model was considered adequate for the alveolar mechanical representation in the proposed condition. With the validated digital model and aiming to obtain less loss of volume and alveolar pressure of the patient model, an intermittent suctioning with parameters of 4 patients was implemented (one healthy, one with a restrictive disease, one with obstructive disease and one critical with both disorders). When comparing normal and intermittent suctioning, there was an improvement in the mean alveolar pressure and a decrease in maximum pressure drop during suctioning in patients.