Regional Distribution of Pulmonary Blood Flow in Normal High-Altitude Dwellers at 3,650 m (12,200 ft)

Abstract

Simultaneous isotope dilution curves were recorded from the right upper (QRUZ) and right lower lung zones (QRLZ) by surface scanning in the sitting and recumbent positions in 15 normal high-altitude-born (HAD) males and in 1 HAD female as well as from 3 male newcomers, using 10 µCi of ¹³¹I-HSA as a bolus injection into the right ventricle. Similar information was also obtained at sea level from 5 normal males. The mean percent distribution of total pulmonary blood flow (Q) to RUZ and RLZ in the two body postures indicate (1) that in the vertical position RUZ in males receives about 17% of Q regardless of altitude and elevation in mean pulmonary artery pressure (MPAP) in HAD of 8.6 mm Hg above that extant at sea level; (2) recumbency at high altitude showed QRUZ also to be lower than at sea level; (3) elevation in MPAP at altitude has no significant effect on changing the sea-level distribution pattern of pulmonary blood flow.

Effects of Posture on Pulmonary Diffusing Capacity and Regional Distribution of Pulmonary Blood Flow in Normal Male and Female High Altitude Dwellers at 3,650 m (12,200 ft)

“…Simultaneous isotope di lution curves, derived from these lung zones by surface scanning in the sitting and re-cumbcnt postures, revealed in male HAD a distribution of about 17% of cardiac output (0 ) to RUZ sitting contrasted with 26.0% in recumbeny. This is almost identical with the flow distribution to RUZ in sitting sealevel males [1] and appears to be uninflu enced by the elevation in mean pulmonary artery pressure (MPAP) of 7.7 mm Hg at La Paz above that extent at sea level.…”

“…The distribution of pulmonary blood flow was studied in accordance with the methods already detailed [1,2] and involved right heart catheteri zation. This was performed at the Cardio-Pulmo-nary Laboratory of the Instituto Boliviano de Biologia de Altura (IBBA) located at the Instituto Na tional de Torax, La Paz, Bolivia.…”

“…22.8 and 21.1% of Q respectively. Table III summarizes the percent distri bution of total Q to four lung zones in nor mal HAD, derived from RUZ and RLZ of a previous study [1] and for the left lung from the current investigation. In male HAD in the vertical posture the means of QRUZ and QLUZ are 17.5 and 16.9% of Q while the means in recumbency for QRUZ and QLUZ were 25.9 and 22.8%, respec tively.…”

Relationship between the Severity of Chest CT Scan Lesions, Arterial Oxygenation and Inflammatory Markers in High – Altitude Patients with Covid-19

“…Concerning D dimer, an average of 320 ug/L was obtained in the Egyptian study [23] and 434 ug/L in the Indian study by Yanamandra [30], values well below those found in Huancayo where the average D dimer was 1295 ug/L in mild cases. The Egyptian study's patients with severe tomographic pulmonary compromise had an average D-dimer of 1210 ug/L.…”

“…This pattern of lower lobes compromise is consistent with the results reported by Malbuisson et al of the CT Scan ARDS Study Group [22], which found that the lower lobes received the greater pressure exerted by the heart and that that increased pressure was even greater in patients with ARDS as compared with normal controls. It is important to note that according to Coudert et al [23], in a study performed in La Paz, Bolivia, at high altitude, in healthy volunteers placed in the recumbent position, pulmonary artery flow was higher in the right lower lobe while lower in the right upper lobe.…”