Abstract：
:At high altitude, hypoxia amplifies oxyhemoglobin saturation (SPO2) swings with changes in respiratory mechanics. Our objective was to examine the effects of posture on SPO2 and determine predictors of postural SPO2 changes in highlanders. 50 native highlanders from Puno, Peru (3825 m) assumed supine and upright-seated postures, in rotating sequence, while undergoing continuous pulse-oximetry. We compared mean SpO2 in each posture with a paired t-test. We examined associations of BMI, age, sex and spirometry with postural SpO2 changes with mixed-effects linear regression. In highlanders, SpO2 was 84% in the supine posture and was 1.0% ± 1.1 (p < 0.0001) greater in the upright-seated posture. Greater postural changes in SpO2 were associated with older age (p = 0.01 for interaction) but not with sex, BMI, FVC or FEV1. In highlanders, SpO2 is higher in the upright-seated compared to supine posture, especially with older age. Because we generally sleep flat, posture may contribute significantly to highlanders' hypoxemic burden during sleep. Postural intervention during sleep may mitigate nocturnal hypoxemia.
journal_name
Respir Physiol Neurobioljournal_title
Respiratory physiology & neurobiologyauthors
Arias RS,Etienne B,Polotsky VY,Checkley W,Schwartz AR,Pham LVdoi
10.1016/j.resp.2019.04.015subject
Has Abstractpub_date
2019-08-01 00:00:00pages
138-143eissn
1569-9048issn
1878-1519pii
S1569-9048(18)30360-4journal_volume
266pub_type
杂志文章abstract：:We examined how the greater vasodilatory capacity of slow--(ST) versus fast-twitch (FT) muscles impacts the relationship between blood flow (Q ) and O2 uptake (VO2) and, consequently, the O2 extraction (a-vO2 diff.)-to-VO2 relationship. Q was measured with radiolabelled microspheres, while VO2 was calculated by the Fi...
journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
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journal_title：Respiratory physiology & neurobiology
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journal_title：Respiratory physiology & neurobiology
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
doi：10.1016/j.resp.2014.09.024
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章,评审
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
doi：10.1016/j.resp.2014.01.009
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章,评审
doi：10.1016/j.resp.2017.01.013
更新日期：2017-05-01 00:00:00
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
doi：10.1016/j.resp.2014.03.010
更新日期：2014-07-01 00:00:00
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
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journal_title：Respiratory physiology & neurobiology
pub_type： 临床试验,杂志文章
doi：10.1016/j.resp.2008.06.008
更新日期：2008-08-31 00:00:00
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
doi：10.1016/j.resp.2013.04.013
更新日期：2013-08-01 00:00:00
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journal_title：Respiratory physiology & neurobiology
pub_type： 临床试验,杂志文章
doi：10.1016/j.resp.2005.03.010
更新日期：2006-02-28 00:00:00
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
doi：10.1016/j.resp.2019.103353
更新日期：2020-03-01 00:00:00
abstract：:Loss of alveolar barrier function is important in the development of pulmonary edema, but quantitation of its integrity has been difficult in the intact lung. We report a new non-radioactive method to assess paracellular and transcellular permeability of alveolar barrier in buffer-perfused rabbit lungs. Changes in alv...
journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
doi：10.1016/s1569-9048(02)00150-7
更新日期：2002-10-23 00:00:00
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
doi：10.1016/j.resp.2004.11.006
更新日期：2005-03-01 00:00:00
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
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更新日期：2011-06-30 00:00:00
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journal_title：Respiratory physiology & neurobiology
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doi：10.1016/j.resp.2009.05.006
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
doi：10.1016/s1569-9048(03)00199-x
更新日期：2003-11-14 00:00:00
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
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更新日期：2013-01-15 00:00:00
abstract：:Seizure-induced cardiorespiratory autonomic dysfunction is a major cause of sudden unexpected death in epilepsy (SUDEP), and the underlying mechanism is unclear. Seizures lead to increased synthesis, and release of glutamate, pituitary adenylate cyclase activating polypeptide (PACAP), and other neurotransmitters, and ...
journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
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更新日期：2016-06-01 00:00:00
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
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更新日期：2008-02-01 00:00:00
abstract：BACKGROUND:A sustained elevation in respiratory drive following removal of the inducing stimulus is known as respiratory long-term facilitation (rLTF). We investigated whether an acute exposure to intermittent negative airway pressure (INAP) elicits rLTF in humans. METHOD:13 healthy males (20.9 ± 2.8 years) undertook ...
journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
doi：10.1016/j.resp.2019.05.016
更新日期：2019-09-01 00:00:00
abstract：BACKGROUND AND OBJECTIVES:Rapid-onset obesity with hypothalamic dysfunction, hypoventilation, and autonomic dysregulation (ROHHAD) is a rare pediatric disease of unknown cause. Here, in response to a recent case report describing a ROHHAD patient who suffered from secondary narcolepsy confirmed by an absence of hypocre...
journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
doi：10.1016/j.resp.2015.11.002
更新日期：2016-01-15 00:00:00
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journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
doi：10.1016/j.resp.2018.03.005
更新日期：2018-06-01 00:00:00
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journal_title：Respiratory physiology & neurobiology
pub_type： 临床试验,杂志文章
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更新日期：2003-03-03 00:00:00
abstract：:Exposure to irritants such as tobacco smoke (TS) causes acute airway inflammation. Chronic exposure may cause airway remodeling contributing to enhanced airway resistance. We hypothesize that combining airway sensitization and inhalation of irritants enhances the number of mucous producing cells beyond either agent al...
journal_title：Respiratory physiology & neurobiology
pub_type： 杂志文章
doi：10.1016/j.resp.2013.07.019
更新日期：2013-12-01 00:00:00
abstract：:We investigated the contributions of obesity on multidimensional aspects of dyspnea on exertion (DOE) in patients referred for clinical cardiopulmonary exercise testing (CPET). Ratings of perceived breathlessness (RPB, Borg scale 0-10) were collected in obese (BMI ≥ 30; n = 47) and nonobese (BMI ≤ 25; n = 27) patients...
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pub_type： 杂志文章
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更新日期：2020-03-01 00:00:00
