Effectiveness of a new breathing device “BreatheMAX®” to increase airway secretion clearance in patients with ventilatory dependence

Abstract

Bronchial mucociliary clearance is impaired in intubated patients receiving mechanical ventilation and thus leads to an accumulation of the secretion in the airway which leads to increase a risk of lung infection and decrease lung function. Physiotherapy airway clearance techniques include conventional manual techniques with and without use of various breathing devices. The present study aimed to determine the effects of a newly developed breathing device (BreatheMAX®) on airway secretions clearance and cardiopulmonary response in intubated patients with mechanical ventilatory dependence. Six patients with mechanical ventilatory dependence (all male, aged 51.2 ± 25.9 yrs) and could breathe spontaneously without the ventilator support for one minute participated in this single blinded randomized cross-over study that had been approved by the Ethical committee. The study consisted of 2 interventions: treatment and sham. In the treatment intervention (A), the patients performed spontaneous deep breathing with steady inspiratory flow against a water pressure resistance of 20 % of their peak inspiratory pressure 10 breaths/set, 10 sets, 1 minute rest between sets. In the sham intervention (B), the protocol was the same but there was no water pressure load. The patients were randomly assigned to receive either treatment or sham in the first round and vise versa in the second round in a balance arm design (ABBA or BAAB). The patients rested for 24 hours between interventions. Airway secretions were collected directly by suction via endotracheal or tracheostomy tube without saline adding.  The mucus was sucked into and kept in mucous extractor with volumetric scale (0-25 cc.) during the three hours before and after intervention.  Secretion clearance rate by weight and by volume per hour and percentage of the change after compared to before intervention were measured. Pulse oxygen saturation (SpO₂), heart rate (HR) and respiratory rate (RR) were monitored before, during and after the intervention. The differences of the dependent variables within each intervention (before – after) and between interventions (A vs B) were analyzed by Wilcoxon’s matched pairs signed rank test. The results showed that the mean of secretion clearance rate was significantly (P = 0.028) increased after (3.73 ± 2.20 g/h or 3.46 ± 1.88 ml/h) compared to before (0.85 ± 0.64 g/h or 0.81 ± 0.59 ml/h) treatment but not with the sham intervention. The mean changes of the clearance rate by weight and by volume was significantly greater by 3.23 ± 2.68 g/h (95% CI: -2.19 – 2.19, 696.55 %) and 3.01±2.48 ml/h (95% CI: -2.02 – 2.02, 632.66 %) respectively. SpO₂, HR, and RR did not change while breathing with the BreatheMAX®. In conclusion, the slow deep breathing with sustained maximal inspiration breathing exercise with the new device, BreatheMAX® is safe to use with intubated patients, and is an effective technique for increasing airway secretion clearance. This breathing exercise with BreatheMAX® could be used alone or as an adjunct to conventional chest physiotherapy to enhance the clearance of airway secretions.