Vital capacity, exercise performance, and blood gases at altitude as related to age

Dill, D. B.; Hillyard, Stanley D.; Miller, J.

doi:10.1152/jappl.1980.48.1.6

Cited by 18 publications

(9 citation statements)

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“…Such observations have also been reported by Dill et al [11] and by Coates et al [12] both at high altitude and in a hypobaric chamber, while Jaeger et al [ 13] demonstrated an increased intrathoracic fluid volume in man at 4,300 m, reducing the elastic properties of the lung.…”

Section: Respiratory Volum Es and Flow S At Altitudesupporting

confidence: 70%

Respiratory Function at Different Altitudes

Cogo

Legnani²,

Allegra³

1997

Respiration

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For the evaluation of a respiratory test at high altitude, several factors must be taken into account: the decreased barometric pressure, the decreased density of air and the degree of acclimatization which is related to the altitude and to the length of exposure. Several studies have shown a reduction in forced vital capacity (FVC) at high altitude and using simulated conditions, mainly related to an increase in pulmonary blood volume and development of interstitial edema. To assess the daily spirometric patterns during ascending to high altitudes we studied 17 healthy subjects at both Capanna Regina Margherita on the Italian Alps (4,559 m) and the Pyramid Laboratory in Nepal (5,050 m). Respiratory function tests were performed every day. Peak expiratory flow values significantly increased. The mean percent increase was 15% at 3,200 and 3,600 m and 26% at 4,559 m. FVC and MEF25 values showed a significant decrease (p < 0.005) during the first days above 3,500 m and improved only after several days spent above this altitude. For each subject the maximal reductions in FVC and maximal expiratory flow (MEF) at 25% of FVC however were found on different days. In our opinion, these data support the hypothesis that at high altitude the respiratory function can be affected by the presence of an increased pulmonary blood volume and/or the development of interstitial edema. The observed changes in forced expiration curves at high altitude seem to reflect the degree of acclimatization that is related to the individual susceptibility, to the altitude reached and to the duration of the exposure. These changes are transient and resolve after returning to sea level.

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Section: Respiratory Volum Es and Flow S At Altitudesupporting

confidence: 70%

Respiratory Function at Different Altitudes

Cogo

Legnani²,

Allegra³

1997

Respiration

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“…Increased susceptibility to acute mountain sickness among younger persons was also noted by Hackett and colleagues (2). This finding is surprising because some physiologic components of gas exchange that maintain oxygenation, such as vital capacity and hypoxic ventilatory drive, decrease with age (25,26). Although not studied, elderly persons who visit high altitudes for recreational activities may be self-selected to include the more healthy persons who curtail their activities on arrival in ways that decrease the incidence of acute mountain sickness.…”

Section: Discussionmentioning

confidence: 99%

Acute Mountain Sickness in a General Tourist Population at Moderate Altitudes

Theis²,

et al. 1993

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“…Increased susceptibility to acute mountain sickness among younger persons was also noted by Hackett and Rennie [2]. Levine et al [3]and Roach et al [4]both noted that the elderly appear to acclimatize well to 2,500 m. These findings are surprising because some physiological components of gas exchange that maintain oxygenation, such as vital capacity and hypoxic ventilatory drive, decrease with age [1, 5, 6]. Levine et al [3]noted that moderate altitude exposure in the elderly is associated with hypoxemia, sympathetic activation, and pulmonary hypertension resulting in a reduced exercise capacity.…”

Section: Introductionmentioning

confidence: 92%

Geriatric Men at Altitude: Hypoxic Ventilatory Sensitivity and Blood Dopamine Changes

et al. 2000

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Background: Short-term exposure to high-altitude hypoxia increases hypoxic ventilatory sensitivity (HVS) in healthy humans. Dopamine (DA) is the implicated neurotransmitter in carotid body (CB) chemoreceptor response, and the microenvironmental conditions in CB tissue are comparable to blood. Continuous DA infusion affected ventilation in animals and humans. Age-related oscillations in blood DA levels may influence peripheral chemoreflexes. Objective: Hypoxic ventilatory responses (HVR) relative to blood DA concentration and its precursor, dihydroxyphenylalanine (DOPA) was measured in young and elderly men during short-term altitude adaptation. Methods: Nine elderly climbers (group 1: 61 ± 1.4 years) and 7 young healthy subjects (group 2: 23 ± 2 years) were tested at sea level on day 0, on day 3 after passive transport to 2,200 m, and on day 14 after climbing to 4,200 and 5,642 m. Results: Sea level HVR in group 1 was 47% lower than in group 2, accompanied by higher blood DOPA (300%) and DA (37%) content. Initial DA and DOPA concentrations showed a negative correlation with initial HVR but a positive correlation with age. Passive transport to middle altitude (2,200 m) increased HVS, doubling HVR slopes in groups 1 and 2 and producing increased maximum expired minute ventilation during isocapnic rebreathing (29 and 28%, respectively). Day 3 2,200-meter blood DOPA content decreased by 22% in group 1 and increased by 300% in group 2. DA increased in both groups. Conclusion: The relationship between HVR and the reciprocal DA and DOPA values seen in both groups is associated with age, producing decreased DA receptor sensitivity and enhanced DA reuptake during adaptation to high altitude.

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Vital capacity, exercise performance, and blood gases at altitude as related to age

Cited by 18 publications

References 0 publications

Respiratory Function at Different Altitudes

Respiratory Function at Different Altitudes

Acute Mountain Sickness in a General Tourist Population at Moderate Altitudes

Geriatric Men at Altitude: Hypoxic Ventilatory Sensitivity and Blood Dopamine Changes

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