Respiratory care
-
Randomized Controlled Trial
Physiologic Effects of High-Flow Nasal Cannula in Healthy Subjects.
High-flow nasal cannula (HFNC) is increasingly used in the management of acute and chronic respiratory failure. Little is known about the optimal settings for HFNC. This study was designed to assess the dose effect of HFNC on respiratory effort indexes and respiratory patterns in spontaneously breathing adults. ⋯ HFNC did not significantly modify work of breathing in healthy subjects. However, a significant reduction in the minute volume was achieved, capillary [Formula: see text] remaining constant, which suggests a reduction in dead-space ventilation with flows > 20 L/min. (ClinicalTrials.gov registration NCT02495675).
-
COVID-19 is devastating health systems globally and causing severe ventilator shortages. Since the beginning of the outbreak, the provision and use of ventilators has been a key focus of public discourse. Scientists and engineers from leading universities and companies have rushed to develop low-cost ventilators in hopes of supporting critically ill patients in developing countries. ⋯ Health care workers in many low-resource settings are already exceedingly overburdened, and pulling these essential human resources away from other critical patient needs could reduce the overall quality of patient care. When deploying medical devices, it is vital to align the technological intervention with the clinical reality. Low-income settings often will not benefit from resource-intensive equipment, but rather from contextually appropriate devices that meet the unique needs of their health systems.
-
Noninvasive ventilation (NIV) is the recommended ventilatory support for acute cardiogenic pulmonary edema (CPE) associated with acute respiratory failure or hypercapnia. High-flow nasal cannula (HFNC) has emerged as an alternative to NIV in acute hypoxemic respiratory failure. We aimed to assess the efficacy of HFNC on early changes in [Formula: see text] and respiratory parameters in patients in the emergency department with acute hypercapnic CPE and to compare it to NIV. ⋯ This preliminary study suggests that HFNC treatment for 1 h improves [Formula: see text] and respiratory parameters in subjects with hypercapnic acute CPE in a manner that is comparable to NIV. Further studies are needed to assess HFNC as a possible alternative to NIV in early management of acute hypercapnic respiratory failure of cardiogenic origin. (ClinicalTrials.gov registration NCT03883555.).
-
Randomized Controlled Trial
Patient-Ventilator Interaction During Noninvasive Ventilation in Subjects With Exacerbation of COPD: Effect of Support Level and Ventilator Mode.
Patient-ventilator synchrony in patients with COPD is at risk during noninvasive ventilation (NIV). NIV in neurally-adjusted ventilatory assist (NAVA) mode improves synchrony compared to pressure support ventilation (PSV). The current study investigated patient-ventilator interaction at 2 levels of NAVA and PSV mode in subjects with COPD exacerbation. ⋯ Increasing PSV levels during NIV caused a progressive mismatch between neural effort and pneumatic timing. Patient-ventilator interaction during NAVA was more synchronous than during PSV, independent of inspiratory support level. (ClinicalTrials.gov registration NCT01791335.).
-
Adaptive servoventilation (ASV) is a recently developed ventilation mode designed to stabilize ventilation in patients with central sleep apnea and Cheyne-Stokes respiration. Alternatively, modes aiming to maintain average ventilation over several breaths, such as average volume-assured pressure support (AVAPS) and intelligent volume-assured pressure support (iVAPS), could be efficient during ventilation instability by reducing central events. These modes are available on a variety of devices. This bench evaluation studied the response of these different modes and devices to simulated transient hypoventilation events. ⋯ ASV devices improved central hypopnea/hypoventilation events without inducing hyperpnea events and therefore were better adapted than AVAPS and iVAPS devices, with notable differences in their responses to hypoventilation events.