Article type: Research Article
Authors: Waltz, Xavier; ; | Hardy-Dessources, Marie-Dominique; | Lemonne, Nathalie | Mougenel, Danièle | Lalanne-Mistrih, Marie-Laure; | Lamarre, Yann; | Tarer, Vanessa | Tressières, Benoit | Etienne-Julan, Maryse | Hue, Olivier | Connes, Philippe; ;
Affiliations: Inserm 665, Pointe-à-Pitre, F-97159 Guadeloupe, Université des Antilles et de la Guyane, Pointe-à-Pitre, F-97157, France | Laboratory of Excellence GR-Ex « The red cell : from genesis to death », PRES Sorbonne Paris Cité, 75015, Paris, France | Université des Antilles et de la Guyane, Laboratoire ACTES (EA 3596), Département de Physiologie, Pointe-à-Pitre, Guadeloupe, France | Unité Transversale de la Drépanocytose, Centre Hospitalier et Universitaire de Pointe-à-Pitre, Pointe-à-Pitre, Guadeloupe, France | CIC-EC 802 Inserm, Centre Hospitalier Universitaire de Pointe-à-Pitre, Pointe-à-Pitre, Guadeloupe, France | Centre de référence maladies rares pour la drépanocytose aux Antilles-Guyane, Centre Hospitalier et Universitaire de Pointe-à-Pitre, Pointe-à-Pitre, Guadeloupe, France
Note: [] Corresponding author: Philippe Connes, PhD, UMR Inserm 665, CHU de Pointe-à-Pitre, 97159, Pointe-à-Pitre, Guadeloupe, France. Tel.: +590 590 83 48 99; Fax: +590 590 83 05; E-mail: pconnes@yahoo.fr
Abstract: The hematocrit-to-viscosity ratio (HVR) has been widely used has an estimate of red blood cell (RBC) oxygen transport effectiveness into the microvasculature or as an oxygen delivery index. However, no study investigated the possibility of HVR to truly reflect RBC oxygen transport effectiveness or to be an oxygen delivery index. We measured blood viscosity at high shear rate (225 s−1), hematocrit, HVR, as well as the microvascular oxyhemoglobin saturation (TOI; tissue oxygen index) by spatial resolved near-infrared spectroscopy (NIRS) at cerebral and muscle levels in three population known to have various degrees of hemorheological abnormalities: healthy subjects (AA), patients with sickle cell SC disease (SC) characterized by moderate anemia and patients with sickle cell anemia (SS) marked by severe anemia. At both the cerebral and muscle level, HVR was positively correlated with TOI (r = 0.28; p = 0.03 and r = 0.38; p = 0.003, at the cerebral and muscle level, respectively). These findings suggest that HVR probably play a key role in blood flow and hemodynamic regulation in the microvasculature, hence modulating the amount of oxygen available for tissues. Nevertheless, the strengths of the associations are weak (R2 < 0.50), suggesting that other determinants modulate microvascular blood flow and oxygenation, such as vascular geometry and vasomotor reserve.
Keywords: Microvascular oxygenation, sickle cell syndromes, hemorheology
DOI: 10.3233/CH-131742
Journal: Clinical Hemorheology and Microcirculation, vol. 59, no. 1, pp. 37-43, 2015
