Saltos del Moconá
Río Uruguay - Misiones
Argentina
Función pulmonar en la población de altura
Dr. Hernando Sala
Hospital Nacional A Posadas
El Palomar - Argentina
Figure 1. Comparison between our sample and values predicted for the same population using NHANES III and
ECCS prediction equations.
When NHANES III or ECCS (8,9) prediction equations are used in our population, observed values of FVC and FEV 1
expressed as percent of predicted, were between 12 and 27% higher than mean predicted values (p<0.001 for all
pairwise comparisons with both variables and both equations, in both genders)
Figure 2. Comparison between our sample and values predicted for the same
population using Havryk´s predicted values developed for Himalayan
population.
DLCO / kCO
Pulmonary capillary blood volume and membrane conductance in Andeans and lowlanders at high altitude: a
cross-sectional study.
de Bisschop C1, et al
Nitric Oxide. 2010 Nov 1;23(3):187-93
The question is whether hypoxia induces pulmonary angiogenesis.
18 highlanders living in Bolivia and 16 European lowlander volunteers were studied.
Membrane conductance (Dm(CO)) and capilar volume, corrected for the haemoglobin concentration (Vc(cor)),
were calculated using the NO/CO transfer technique. Pulmonary arterial pressure and left atrial pressures
were estimated using echocardiography.
Highlanders exhibited significantly higher NO and CO transfer than acclimatised lowlanders, with Vc(cor)/VA
and Dm(CO)/VA being 49 and 17% greater (VA: alveolar volume) in highlanders, respectively.
The disproportionate increase in Vc in Andeans compared to the change in Dm(CO) suggests that the
recruitment of capillaries is associated with a thickening of the blood capillary sheet. Since there was no
correlation between the increase in Vc and the slight alterations in haemodynamics, this data suggests
that chronic hypoxia might stimulate pulmonary angiogenesis in Andeans who live at high altitudes.
Control de la ventilación
Respiratory control in lowlanders and Sherpa highlanders at altitude.
Milledge JS, et al
Respir Physiol. 1967 May;2(3):310-22.
Breath holding and rebreathing at low and high altitude.
Gautier H, et al
Respir Physiol. 1975 Mar;23(2):201-7.
Breath holding and rebreathing have been carried out at sea level in lowlanders and at high altitude in
acclimatized lowlanders and in highlanders. It has been shown that the values of gasping time, breathholding time, rebreathing time and the composition of the alveolar gases at the breaking point are
modified by chronic hypoxia, especially in highlanders. The modifications observed can be explained by
different sensitivities to humoral stimuli of the different groups of subjects. The importance of
nonhumoral factors, as studied by comparing apnea and rebreathing, seems modified at altitude,
especially in highlanders, although the mechanism of this change is unknown.
Mean ±s.e.m. breath-by-breath ventilation vs. pCO2 during isoxic hyperoxic and hypoxic Duffin's rebreathing tests for
all highlander and lowlander subjects
There was difference in ventilatory recruitment thresholds (VRTs) between populations
Differences in the control of breathing between Himalayan and sea-level residents.
Slessarev M1, Prisman E, Ito S, Watson RR, Jensen D, Preiss D, Greene R, Norboo T, Stobdan T, Diskit D, Norboo
A, Kunzang M, Appenzeller O, Duffin J,Fisher JA.
J Physiol. 2010 May 1;588(Pt 9):1591-606.
Differences in the control of breathing between Andean highlanders and lowlanders
after 10 days acclimatization at 3850 m.
Slessarev M1, Mardimae A, Preiss D, Vesely A, Balaban DY, Greene R, Duffin J, Fisher JA.
J Physiol. 2010 May 1;588(Pt 9):1607-21.
Control of breathing in Andean highlanders is different from that in acclimatizing lowlanders, although there are
some similarities.
Acclimatizing lowlanders have relatively lower non-chemoreflex drives to breathe, increased ventilatory
sensitivities to CO(2), and an altered pattern of ventilatory response to CO(2).
Similar to highlanders and unlike lowlanders at sea-level, acclimatizing lowlanders respond to hypobaric hypoxia
by decreasing their VRT instead of changing their ventilatory sensitivity to CO(2).
There was no difference in ventilatory recruitment thresholds (VRTs) between populations (P = 0.209)
Sleep Apnea
Sleep apneas in high altitude residents (3,800 m).
Normand H1, Vargas E, Bordachar J, Benoit O, Raynaud J.
Int J Sports Med. 1992 Oct;13 Suppl 1:S40-2.
Standard sleep parameters, chest wall movements, temperature of ventilated gas and
arterial O2 saturation (SaO2) were continuously recorded in 7
normal highlanders (mean hematocrit: 51%) and 14 polycythemic highlanders (mean
hematocrit: 68%) during one night in La Paz, 3,850 m, Bolivia.
The patterns of breathing instability were analysed by two ways: measuring duration of
apneas and counting all the oscillations of SaO2 greater than 1%.
The longest apneas and the highest number of oscillations of SaO2 were found in the
polycythemic highlanders.
Ejercicio
• Maximal exercise capacity in adolescent European and
Amerindian high-altitude natives.
•
•
Greksa LP, Spielvogel H, Paredes-Fernández L.
Am J Phys Anthropol. 1985 Jul;67(3):209-16.
• Forty-seven highland natives were given maximal exercise tests on a
treadmill ergometer at 3,600 m. The subjects were grouped into
four subsamples on the basis of ethnicity (European vs. Aymara)
and age (young vs. old adolescent).
• VO2max, an integrated measure of the overall functional capacity
of the oxygen transport system, did not differ significantly between
ethnic groups, suggesting that both groups are equally capable of
meeting the body's oxygen requirements during maximal exercise
at high altitude.
Circulación Pulmonar
The heart and pulmonary circulation at high altitudes: healthy highlanders and chronic mountain
sickness.
Penalize D1, et al
Circulation. 2007 Mar 6;115(9):1132-46.
More than 140 million people worldwide live >2500 m above sea level. Of them, 80 million live in
Asia, and 35 million live in the Andean mountains.
Pulmonary hypertension in healthy highlanders is related to a delayed postnatal remodeling of the
distal pulmonary arterial branches. The magnitude of pulmonary hypertension increases with the
altitude level and the degree of exercise. There is reversal of pulmonary hypertension after
prolonged residence at sea level.
The heart and pulmonary circulation in healthy highlanders have distinct features in comparison
with residents at sea level.
Chronic mountain sickness is a public health problem in the Andean mountains and other
mountainous regions around the world. Therefore, dissemination of preventive and therapeutic
measures is essential.
Respiratory health and indoor air pollution at high elevation.
Rosati JA, Yoneda KY, Yasmeen S, Wood S, Eldridge MW.
Arch Environ Occup Health. 2005 Mar-Apr;60(2):96-105.
In this research, the authors sought to provide experimental data on indoor air quality, and the
resulting respiratory impact, for a high-elevation (4550 m), rural community in Ladakh, India. This community is of
interest because the primarily nomadic residents burn biomass inside the home for heating and cooking.
Concentrations of particulate, sputum samples, and lung function data were collected
Although the high levels of indoor pollutants did not correlate with significant decrements in lung function, the
induced sputum analysis revealed marked airway inflammation dominated by macrophages and neutrophils.
It appears that augmented lung mechanics of this high-altitude population are adaptive to reduce the work of
breathing; thus, decrements in lung function go undetected because the true predicted values are greater than
expected.
Meseta de Somuncurá
Patagonia
Muchas Gracias
Lung elasticity and airway dynamics in Peruvian natives to high altitude.
Brody JS, Lahiri S, Simpser M, Motoyama EK, Velasquez T.
J Appl Physiol Respir Environ Exerc Physiol. 1977 Feb;42(2):245-51.
Abstract
To evaluate the role of genetic and environmental factors in the genesis of large lungs in highaltitude natives, we measured forced vital capacity (FVC), static lung pressure-volume
characteristics and maximum expiratory flow-volume loops in 17- to 20-yr-old Peruvian natives to
3,850 m (highlanders) and 800 m (lowlanders). Forced vital capacity was 5.11 +/- 0.64 liters
in highlanders, 116 +/- 11% of predicted; and 3.73 +/- 0.32 liters in lowlanders, 84 +/- 7% of
predicted. Lung elastic recoil at functional residual capacity and at total lung capacity, and sizecorrected pressure volume curves were similar in the two groups. Despite the larger volumes
in highlanders, density-corrected maximum flow rates were similar in highlandersand lowlanders,
and flow expressed in FVC'S-S-1 was less in highlanders. Upstream conductance at 50% FVC
expressed in fvc's-s-1-cmH2O was 0.094 +/- 0.023 in highlanders vs. 0.147 +/- 0.050 in
lowlanders. Flow rates did not change in sojourners to altitude, suggesting that the lower values
of highlanders were due to anatomic factors. These findings suggest that airways, which form in
fetal life, do not participate in adaptation to altitude, and that the large lungs
of highlanders result from postnatal environmental hypoxic stimulation of lung growth. Our
results illustrate the importance of "dysynaptic" lung growth in determining patterns of
adult lung function.