Hemodynamic response to low-flow acute supplemental oxygen in idiopathic pulmonary fibrosis and elderly healthy subjects

Effects of Supplemental Oxygen on Cardiovascular and Respiratory Interactions by Extended Partial Directed Coherence in Idiopathic Pulmonary Fibrosis

“…Also, a thoracic belt was used to acquire the respiratory signal and all signals were sampled at 1,000 Hz. Raw signals were acquired in supine position continuously during 10 min with the subjects breathing spontaneously ambient air (AA) and an additional 10 min breathing SupplO 2 at 3 L/min to ensure an arterial oxygen saturation above 94% (Santiago-Fuentes et al, 2021). Time series of successive beat-tobeat intervals (BBI), respiratory amplitude (RESP) at BBI onset as well as systolic (SYS) and diastolic (DIA) blood pressure (BP) were extracted from recorded signals; all extracted time series were manually reviewed and corrected.…”

“…Also, it is relevant to point out that the population of this age was under medication for other comorbidities. A comprehensive discussion of this aspect for the groups under study can be found in (Santiago-Fuentes et al, 2021).…”

“…Systolic pressure, being a variable to control, tends to oscillate with greater amplitude when feedback mechanisms are deficient, showing an inverse relationship with variations in heart rate, as a variable to regulate (Mancia et al, 1986;Lanfranchi and Somers, 2002). In fact, it should be noted that the significant reduction in cardiac output in IPF observed during SupplO 2 (Santiago-Fuentes et al, 2021) could be a consequence of alteration of the cardiovascular regulation. The former behavior may be explained, on the one hand, by statistically significant changes (attenuation) of the sensitivity of the baroreceptors reflected by bslope and tslope indices (Figures 1K,L), increase in BBI (Figure 1B), and in total peripheral resistance and, on the other hand, by statistically nonsignificant trends in systolic blood pressure and its variability.…”

“…Also, in the HF band Traube-Hering waves (THW) have been reported associated with respiratory-related fluctuations in sympathetic outflow that promotes changes in vascular tone (Menuet et al, 2020). In fact, the IPF group showed a significant increased TPR during AA, i.e., increased vascular tone (Santiago-Fuentes et al, 2021). In the case of SYS → BBI interaction there were no statistically significant differences and consequently, the corresponding TFR i is not shown.…”

“…It is important to point out that few studies have addressed the efficiency of oxygen administration in COPD and Interstitial Lung Disease (ILD) patients (Khor et al, 2019) and that studies about the ANS regulation in COPD patients were based on classic heart rate variability (HRV) parameters (Mohammed et al, 2017). Regarding IPF disorder, the authors of the present contribution compared the hemodynamic response to SupplO 2 between ill and healthy subjects, showing potential detrimental effects of SupplO 2 on IPF hemodynamics, particularly on total peripheral resistance (TPR) and cardiac output (Santiago-Fuentes et al, 2021).…”