Article Figures & Data
Figures
- Fig. 1.
Several factors may cause asynchrony, some related to patient characteristics (eg, respiratory mechanics, effort), others related to the ventilator (eg, setting, level of assistance, cycling criteria) and to the interface used (ie, invasive or noninvasive). NIV = noninvasive ventilation.
- Fig. 2.
Asynchronies are common in both obstructive and restrictive patients, although alterations of the underlying respiratory mechanics generate different types of asynchronies. FRC = functional residual capacity; Te = expiratory time constant.
- Fig. 3.
Representative waveforms of flow (red track), Paw (yellow track), and Pes (blue track) in a patient receiving ventilatory support. The blue arrow shows a delay of > 100 ms between the beginning of inspiratory muscle activity and the beginning of mechanical inflation (ie, trigger delay). Paw = airway pressure; Pes = esophageal pressure.
- Fig. 4.
Representative waveforms of flow (red track), Paw (yellow track), and Pes (blue track) in a patient receiving ventilatory support. Arrows indicate ineffective effort. The ventilator is enable to detect the patient’s effort as a deflection on Pes generating only a bump in Flow and Paw tracings. Paw = airway pressure; Pes = esophageal pressure.
- Fig. 5.
Representative waveforms of flow (red track), Paw (yellow track), and Pes (blue track) in a patient receiving ventilatory support showing 2 samples of auto-triggering (blue arrows). A: 3 mandatory breaths are delivered in the absence of the patient’s inspiratory effort, separated by a very short expiratory time. B: A single mandatory breath is delivered in the absence of the patient’s inspiratory effort. Paw = airway pressure; Pes = esophageal pressure.
- Fig. 6.
Representative waveforms of flow (red track), Paw (yellow track), and Pes (blue track) in a patient receiving ventilatory support. The figure shows a double-triggering in the pressure support ventilation mode depicted by the presence of 2 inspiratory cycles separated by a very short expiratory time. Paw = airway pressure; Pes = esophageal pressure.
- Fig. 7.
Clinical implication of poor patient-ventilator interactions. VIDD = ventilator-induced diaphragmatic dysfunction.
