scholarly journals Excessive Gas Exchange Impairment during Exercise in A Subject with A History of Bronchopulmonary Dysplasia And High Altitude Pulmonary Edema

2007 ◽  
Vol 8 (1) ◽  
pp. 62-67 ◽  
Author(s):  
Andrew T. Lovering ◽  
Lee M. Romer ◽  
Hans C. Haverkamp ◽  
John S. Hokanson ◽  
Marlowe W. Eldridge
2015 ◽  
Vol 31 (1) ◽  
pp. 81-86 ◽  
Author(s):  
K. P. Mishra ◽  
Navita Sharma ◽  
Poonam Soree ◽  
R. K. Gupta ◽  
Lilly Ganju ◽  
...  

1996 ◽  
Vol 81 (2) ◽  
pp. 922-932 ◽  
Author(s):  
A. Podolsky ◽  
M. W. Eldridge ◽  
R. S. Richardson ◽  
D. R. Knight ◽  
E. C. Johnson ◽  
...  

Ventilation-perfusion (VA/Q) mismatch has been shown to increase during exercise, especially in hypoxia. A possible explanation is subclinical interstitial edema due to high pulmonary capillary pressures. We hypothesized that this may be pathogenetically similar to high-altitude pulmonary edema (HAPE) so that HAPE-susceptible people with higher vascular pressures would develop more exercise-induced VA/Q mismatch. To examine this, seven healthy people with a history of HAPE and nine with similar altitude exposure but no HAPE history (control) were studied at rest and during exercise at 35, 65, and 85% of maximum 1) at sea level and then 2) after 2 days at altitude (3,810 m) breathing both normoxic (inspired Po2 = 148 Torr) and hypoxic (inspired Po2 = 91 Torr) gas at both locations. We measured cardiac output and respiratory and inert gas exchange. In both groups, VA/Q mismatch (assessed by log standard deviation of the perfusion distribution) increased with exercise. At sea level, log standard deviation of the perfusion distribution was slightly higher in the HAPE-susceptible group than in the control group during heavy exercise. At altitude, these differences disappeared. Because a history of HAPE was associated with greater exercise-induced VA/Q mismatch and higher pulmonary capillary pressures, our findings are consistent with the hypothesis that exercise-induced mismatch is due to a temporary extravascular fluid accumulation.


1989 ◽  
Vol 66 (3) ◽  
pp. 1152-1157 ◽  
Author(s):  
Y. Matsuzawa ◽  
K. Fujimoto ◽  
T. Kobayashi ◽  
N. R. Namushi ◽  
K. Harada ◽  
...  

It has been proposed that subjects susceptible to high-altitude pulmonary edema (HAPE) show exaggerated hypoxemia with relative hypoventilation during the early period of high-altitude exposure. Some previous studies suggest the relationship between the blunted hypoxic ventilatory response (HVR) and HAPE. To examine whether all the HAPE-susceptible subjects consistently show blunted HVR at low altitude, we evaluated the conventional pulmonary function test, hypoxic ventilatory response (HVR), and hypercapnic ventilatory response (HCVR) in ten lowlanders who had a previous history of HAPE and compared these results with those of eight control lowlanders who had no history of HAPE. HVR was measured by the progressive isocapnic hypoxic method and was evaluated by the slope relating minute ventilation to arterial O2 saturation (delta VE/delta SaO2). HCVR was measured by the rebreathing method of Read. All measurements were done at Matsumoto, Japan (610 m). All the HAPE-susceptible subjects showed normal values in the pulmonary function test. In HCVR, HAPE-susceptible subjects showed relatively lower S value, but there was no significant difference between the two groups (1.74 +/- 1.16 vs. 2.19 +/- 0.4, P = NS). On the other hand, HAPE-susceptible subjects showed significantly lower HVR than control subjects (-0.42 +/- 0.23 vs. -0.87 +/- 0.29, P less than 0.01). These results suggest that HAPE-susceptible subjects more frequently show low HVR at low altitude. However, values for HVR were within the normal range in 2 of 10 HAPE-susceptible subjects. It would seem therefore that low HVR alone need not be a critical factor for HAPE. This could be one of several contributing factors.


Circulation ◽  
2000 ◽  
Vol 101 (12) ◽  
pp. 1418-1422 ◽  
Author(s):  
Masayuki Hanaoka ◽  
Masao Tanaka ◽  
Ri-Li Ge ◽  
Yunden Droma ◽  
Atsuko Ito ◽  
...  

1989 ◽  
Vol 67 (5) ◽  
pp. 1982-1989 ◽  
Author(s):  
A. Kawashima ◽  
K. Kubo ◽  
T. Kobayashi ◽  
M. Sekiguchi

To verify the presence of the constitutional abnormality implicated in the pathogenesis of high-altitude pulmonary edema (HAPE), we evaluated the hemodynamic responses to hypoxia, hypobaria, and exercise in HAPE-susceptible subjects (HAPE-S). HAPE-S were five males with a history of HAPE. Five healthy volunteers who had repeated experiences of mountain climbing without any history of altitude-related problems served as controls. HAPE-S showed much greater increase in pulmonary vascular resistance index (PVRI) than the control subjects, resulting in a much higher level of pulmonary arterial pressure (Ppa), under both acute hypoxia of 15% O2 (Ppa = 29.0 +/- 2.8 vs. 17.8 +/- 0.3 Torr, P less than 0.05) and acute hypobaria of 515 Torr (32.3 +/- 2.8 vs. 19.1 +/- 0.8 Torr, P less than 0.05). Also, PVRI in HAPE-S exhibited a tendency to increase even during light exercise with supine bicycle ergometer (50 W), whereas PVRI in the control subjects significantly decreased, so that HAPE-S showed a greater increase in Ppa (delta Ppa = 16.0 +/- 1.5 vs. 4.9 +/- 1.1 Torr, P less than 0.001) and a greater decrease in arterial oxygen tension (17.8 +/- 4.7 vs. 5.6 +/- 1.7 Torr, P less than 0.05). We thus conclude that HAPE-S have a constitutional abnormality, which can be evaluated at low altitude, in the pulmonary circulatory responses to possible causative factors of HAPE such as hypoxia, hypobaria, and exercise.


2018 ◽  
Vol 3 (3) ◽  
pp. 224
Author(s):  
Kaushik Halder ◽  
RK Gupta ◽  
Anjana Pathak ◽  
Montu Saha

<p>The study was aimed to evaluate and compare resting and exercise induced metabolic responses between acclimatized high altitude pulmonary edema (HAPE) susceptible (HAPE-s) and HAPE resistance (HAPE-r) volunteers at sea level. A group of 14 Indian soldiers volunteered for this study, divided into two groups, (i) HAPE-s, with past history of HAPE [n<sub>1</sub> = 7; age = 33.3 ± 4.5 (M ± SD)] and (ii) HAPE-r, with prior history of repeated exposure to high altitude and without suffering HAPE [n<sub>2</sub> = 7; age = 31.9 ± 4.2 (M ± SD)]. Respiratory frequency (f<sub>R</sub>), tidal volume (<sub>T</sub>), minute ventilation (<sub>E</sub>), oxygen consumption (O<sub>2</sub>), carbon dioxide output (CO<sub>2</sub>), heart rate (HR) and respiratory quotient (RQ) were recorded on all the volunteers during resting and exercise conditions. Ventilatory equivalent for oxygen (EqO<sub>2</sub>) and oxygen pulse (O<sub>2</sub>P) were calculated. Significant differences were observed between HAPE-s and HAPE-r volunteers in f<sub>Rrest </sub>(25.3% higher), O<sub>2</sub>P<sub>rest </sub>(23.7% lower), <sub>Emax</sub> (50.9% lower) (all P&lt;0.05), f<sub>Rmax </sub>(55.7% lower), O<sub>2max </sub>(55.5% lower), O<sub>2</sub>P<sub>max </sub>(34.2% lower) (all P&lt;0.01) and CO<sub>2max</sub> (42.1% lower, P&lt;0.001). Rest of the parameters did not show any significant differences between the study groups. The study revealed that resting and exercise induced metabolic responses of HAPE-r volunteers was better as compared to acclimatized HAPE-s volunteers at sea level.</p>


2017 ◽  
Vol 122 (4) ◽  
pp. 844-852 ◽  
Author(s):  
Michael D. Patz ◽  
Rui C. Sá ◽  
Chantal Darquenne ◽  
Ann R. Elliott ◽  
Amran K. Asadi ◽  
...  

High-altitude pulmonary edema (HAPE) is a potentially fatal condition affecting high-altitude sojourners. The biggest predictor of HAPE development is a history of prior HAPE. Magnetic resonance imaging (MRI) shows that HAPE-susceptible (with a history of HAPE), but not HAPE-resistant (with a history of repeated ascents without illness) individuals develop greater heterogeneity of regional pulmonary perfusion breathing hypoxic gas (O2 = 12.5%), consistent with uneven hypoxic pulmonary vasoconstriction (HPV). Why HPV is uneven in HAPE-susceptible individuals is unknown but may arise from regionally heterogeneous ventilation resulting in an uneven stimulus to HPV. We tested the hypothesis that ventilation is more heterogeneous in HAPE-susceptible subjects ( n = 6) compared with HAPE-resistant controls ( n = 7). MRI specific ventilation imaging (SVI) was used to measure regional specific ventilation and the relative dispersion (SD/mean) of SVI used to quantify baseline heterogeneity. Ventilation heterogeneity from conductive and respiratory airways was measured in normoxia and hypoxia (O2 = 12.5%) using multiple-breath washout and heterogeneity quantified from the indexes Scond and Sacin, respectively. Contrary to our hypothesis, HAPE-susceptible subjects had significantly lower relative dispersion of specific ventilation than the HAPE-resistant controls [susceptible = 1.33 ± 0.67 (SD), resistant = 2.36 ± 0.98, P = 0.05], and Sacin tended to be more uniform (susceptible = 0.085 ± 0.009, resistant = 0.113 ± 0.030, P = 0.07). Scond was not significantly different between groups (susceptible = 0.019 ± 0.007, resistant = 0.020 ± 0.004, P = 0.67). Sacin and Scond did not change significantly in hypoxia ( P = 0.56 and 0.19, respectively). In conclusion, ventilation heterogeneity does not change with short-term hypoxia irrespective of HAPE susceptibility, and lesser rather than greater ventilation heterogeneity is observed in HAPE-susceptible subjects. This suggests that the basis for uneven HPV in HAPE involves vascular phenomena. NEW & NOTEWORTHY Uneven hypoxic pulmonary vasoconstriction (HPV) is thought to incite high-altitude pulmonary edema (HAPE). We evaluated whether greater heterogeneity of ventilation is also a feature of HAPE-susceptible subjects compared with HAPE-resistant subjects. Contrary to our hypothesis, ventilation heterogeneity was less in HAPE-susceptible subjects and unaffected by hypoxia, suggesting a vascular basis for uneven HPV.


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