Relationship between hypoxia and pulmonary microcirculation hemorheology in pediatric patients with patent ductus arteriosus operated at a moderate altitude

Abstract

Hypobaric hypoxia due to altitude is a risk factor for patent ductus arteriosus (PDA). In order to explore a relationship between hypoxia and pulmonary microcirculation hemorheology in pediatric patients with surgically corrected PDA, a clinical case control study was carried out in a single medical center at a mean moderate altitude of 2240 meters above sea level (mASL). Patients were divided in two groups, with hypoxia (problems) and without hypoxia (controls), using conventional gasometric criteria. The problem group showed a higher hematocrit value. This suggests that an increase in blood viscosity due to the higher hematocrit level in response to altitude is a factor that promotes hypoxia in the pulmonary microcirculation. A pathophysiological explanation for this acute response in the problem group is provided.