Influence of respiratory pressure support on hemodynamics and exercise tolerance in patients with COPD

Abstract

Inspiratory pressure support (IPS) plus positive end-expiratory pressure (PEEP) ventilation might potentially interfere with the "central" hemodynamic adjustments to exercise in patients with chronic obstructive pulmonary disease (COPD). Twenty-one non- or mildly-hypoxemic males (FEV(1) = 40.1 +/- 10.7% predicted) were randomly assigned to IPS (16 cmH(2)O) + PEEP (5 cmH(2)O) or spontaneous ventilation during constant-work rate (70-80% peak) exercise tests to the limit of tolerance (T (lim)). Heart rate (HR), stroke volume (SV), and cardiac output (CO) were monitored by transthoracic cardioimpedance (Physioflow, Manatec, France). Oxyhemoglobin saturation was assessed by pulse oximetry (SpO(2)). At similar SpO(2), IPS(16) + PEEP(5) was associated with heterogeneous cardiovascular effects compared with the control trial. Therefore, 11 patients (Group A) showed stable or increased Delta "isotime" - rest SV [5 (0-29) mL], lower DeltaHR but similar DeltaCO. On the other hand, DeltaSV [-10 (-15 to -3) mL] and DeltaHR were both lower with IPS(16) + PEEP(5) in Group B (N = 10), thereby reducing DeltaCO (p < 0.05). Group B showed higher resting lung volumes, and T (lim) improved with IPS(16) + PEEP(5) only in Group A [51 (-60 to 486) vs. 115 (-210 to 909) s, respectively; p < 0.05]. We conclude that IPS(16) + PEEP(5) may improve SV and exercise tolerance in selected patients with advanced COPD. Impaired SV and CO responses, associated with a lack of enhancement in exercise capacity, were found in a sub-group of patients who were particularly hyperinflated at rest.

Use of positive expiratory pressure during six minute walk test: results in patients with moderate to severe chronic obstructive pulmonary disease

“…The application of a positive expiratory pressure improved the distance walked in 6MWT compared to controls [29]. The expiratory positive expiratory positive airway pressure promotes collateral ventilation, prevents airway collapse during expiration and thus reduces air trapping [29,30]. …”

Additive effects of non‐invasive ventilation to hyperoxia on cerebral oxygenation in COPD patients with exercise‐related O2 desaturation

“…NIV (16 cmH 2 O of inspiratory pressure support (IPS) and 5 cmH 2 O of positive end‐expiratory pressure (PEEP)) plus HOx (FiO 2 = 0·4) or sham NIV (7 cmH 2 O of IPS and 5 cmH 2 O of PEEP) plus HOx (FiO 2 = 0·4) were applied via a tight‐fitting partial‐face mask with pressures being delivered by a commercially available mechanical ventilator (EVITA 4™, Draeger Medical AG & Co., Lübeck, Germany) in the Assisted Spontaneous Breathing™ mode. These values were selected upon previous evidence that 16 cmH 2 O was associated with positive haemodynamic effects in a population the similar levels of ventilatory impairment (Oliveira et al ., ). Low‐level (5 cmH 2 O) PEEP has been advocated during IPS to counterbalance intrinsic PEEP and prevent small airways closure (Keilty et al ., ).…”

“…To answer the question of whether improvements in systemic haemodynamics would simultaneously increase exercise COx in O 2 desaturators with COPD, we designed a prospective study in which CaO 2 was maintained constant by HOx, whereas Q T was made higher via non‐invasive positive pressure ventilation (NIV) (Oliveira et al ., ). It was our main hypothesis that Q T and COx would be improved with NIV + HOx compared with sham NIV + HOx.…”

Non-Invasive Ventilation as an Adjunct to Exercise Training in Chronic Ventilatory Failure: A Narrative Review

“…However, the cardiovascular effects of the intrathoracic pressures during exercise in patients with CVF and different cardiovascular functions are unknown. A study indicated that NIV with IPAP (16 cm H 2 O) and EPAP (5 cm H 2 O) may improve stroke volume and exercise tolerance in selected patients with advanced COPD [65]. However, impaired responses of stroke volume and cardiac output, associated with a lack of improvement in exercise capacity, were found in a sub-group of patients with severe hyperinflation at rest [65].…”

“…A study indicated that NIV with IPAP (16 cm H 2 O) and EPAP (5 cm H 2 O) may improve stroke volume and exercise tolerance in selected patients with advanced COPD [65]. However, impaired responses of stroke volume and cardiac output, associated with a lack of improvement in exercise capacity, were found in a sub-group of patients with severe hyperinflation at rest [65]. Therefore, a preliminary evaluation of lung and cardiac function should be performed prior to submission to exercise with NIV.…”