Pregnancy at high altitude in the Andes leads to increased total vessel density in healthy newborns

Abstract

The developing human fetus is able to cope with the physiological reduction in oxygen supply occurring in utero. However, it is not known if microvascularization of the fetus is augmented when pregnancy occurs at high altitude. Fifty-three healthy term newborns in Puno, Peru (3,840 m) were compared with sea-level controls. Pre- and postductal arterial oxygen saturation (SpO2) was determined. Cerebral and calf muscle regional tissue oxygenation was measured using near infrared spectroscopy (NIRS). Skin microcirculation was noninvasively measured using incident dark field imaging. Pre- and postductal SpO2 in Peruvian babies was 88.1 and 88.4%, respectively, which was 10.4 and 9.7% lower than in newborns at sea level (P < 0.001). Cerebral and regional oxygen saturation was significantly lower in the Peruvian newborns (cerebral: 71.0 vs. 74.9%; regional: 68.5 vs. 76.0%, P < 0.001). Transcutaneously measured total vessel density in the Peruvian newborns was 14% higher than that in the newborns born at sea level (29.7 vs. 26.0 mm/mm(2); P ≤ 0.001). This study demonstrates that microvascular vessel density in neonates born to mothers living at high altitude is higher than that in neonates born at sea level.

The increase in hemoglobin concentration with altitude varies among human populations

“…Niermeyer and colleagues found that [Hb] in Tibetan newborns was lower compared with Han Chinese newborns . There was no difference in [Hb] in Puno (3840 m) between newborn indigenous Aymaras, Hispanic, and mixed origin people . [Hb] increased linearly in Quechua boys by approximately 2.7 g/dL between the age of 6 and 21 years, which is in the same range as found in Caucasian boys and similar to the age‐related increase of Tibetan and Han Chinese children .…”

Selection Signatures Analysis Reveals Genes Associated with High-Altitude Adaptation in Tibetan Goats from Nagqu, Tibet

“…Angiogenesis is one of the key mechanisms of high-altitude adaptation [ 36 , 37 ]. Remarkably, FGF2 (fibroblast growth factor 2) ( di value = 10.53), one of the fibroblast growth factor family members ( FGFs) [ 38 ], has been proved as an angiogenic growth factor [ 39 ].…”

Second consensus on the assessment of sublingual microcirculation in critically ill patients: results from a task force of the European Society of Intensive Care Medicine

“…In 2009, an international multicenter observational prevalence study in intensive care patients involving 36 ICUs worldwide enrolling 501 patients identified microcirculatory alterations (microvascular flow index, MFI < 2.6) in combination with tachycardia (heart rate > 90) as an independent risk factor for increased hospital mortality [28]. Various studies have been undertaken to define normal values in adults, newborns, and neonates [29][30][31][32][33], as well as in healthy individuals under extreme environmental conditions [34,35]. In studies where systemic hemodynamic monitoring was being applied, it became increasingly clear that microcirculatory alterations can occur independently from systemic hemodynamic alterations and that these microcirculatory alterations were independently associated with adverse clinical outcome [6][7][8].…”