Infusion of atriopeptin into humans and animals induces diuresis, natriuresis, hemodynamic changes, and an increase in arterial hematocrit. The objective of the present study was to elucidate the mechanism(s) responsible for the increase in hematocrit in rats given atriopeptin-24 (AP-24). Infusion of AP-24 for 30 minutes increased large vessel and total vascular hematocrits by 10-15% while decr...

OBJECTIVE Deferral of blood donors due to low hematocrit and iron depletion is commonly reported in blood banks worldwide. This study evaluated the risk factors for low hematocrit and iron depletion among prospective blood donors in a large Brazilian blood center. METHOD A case-control study of 400 deferred donors due to low hematocrit and 456 eligible whole blood donors was conducted between...

Blood Volume, Hematocrit and Pressure Relationships in the Isolated Perfused Dog Brain • The intracranial blood volume and hematocrit of the isolated perfused dog brain preparation were determined with Cr-labeIed erythrocytes. The intracranial blood volume was determined to be 8.6 ml/100 gm brain (SE±1.2 ml). Over the range of perfusing hematocrits studied, the relationship of perfusing hematoc...

This study reports the effect of increased hematocrit (packed cell volume) on the rate of decrease in plasma glucose during 6 h in blood specimens from seven newborns (cord blood) and heparin-treated blood specimens from eight adults. Mean hematocrits ranged frm 0.43 to 0.75 for the adults and from 0.51 to 0.81 for the infants. The decrease in glucose was related to time and to hematocrit. For ...

This study addresses the hypothesis that patients with obstructive sleep apnea, who exhibit recurrent episodes of oxygen desaturation at night, have higher hematocrit levels than nonapneic control subjects. We prospectively studied 624 patients referred to the sleep disorders center at St. Michael's Hospital because of suspicion of sleep apnea. All patients had nocturnal polysomnography and mea...

Micropore filtration of dilute red blood cell (RBC) suspensions is a widely known method for determining red blood cell deformability. Use of this method for cells from various laboratory animal species does require considering the effects of the cell size to pore size ratio and of suspension hematocrit. In general, previous animal studies have utilized 5% hematocrit suspensions and five micron...

The relationship between the indicence of cerebral infarction and the hematocrit was studied using 432 consecutive autopsied patients with the average age of 77.1 years. The incidence of cerebral infraction was higher in patients with hematocrit values of more than 46%, (the average in younger adult subjects). The increase in the frequency of cerebral infarction with high hematocrit values was ...

A population-based study of the relation between hematocrit and stroke subtype was carried out among 2,077 individuals using the Lehigh Valley Stroke Register. This register identifies all stroke patients admitted to the 8 acute care hospitals serving the Lehigh Valley area of eastern Pennsylvania-western New Jersey. The mean hematocrit was higher in patients with lacunes than with thrombotic o...

An isolated perfused canine lung preparation in which determinants of vascular caliber could be individually controlled was developed. The relation of pulmonary arterial (Pa), venous (PV), and alveolar (PA) pressures was such that Pa greater than PA greater than PV throughout the whole lung. The addition of isoprenaline to the perfusate abolished vascular reactivity. Once stability was reached,...