| Japanese |
|---|
| Title | 循環血液量測定法の問題点 |
|---|
| Subtitle | 原著 |
|---|
| Authors | 渋谷穰, S.N.Albert, C.A.Albert, 平松慶博 |
|---|
| Authors(kana) | |
|---|
| Organization | Anesthesiology Research Laboratory, Washington Hospital Center |
|---|
| Journal | 核医学 |
|---|
| Volume | 2 |
|---|
| Number | 3/4 |
|---|
| Page | 166-172 |
|---|
| Year/Month | 1965/12 |
|---|
| Article | 原著 |
|---|
| Publisher | 日本核医学会 |
|---|
| Abstract | 「緒言」放射性同位元素による循環血液量測定時に, その検査成績がときに臨床所見と相反するため, 診断ならびに処理上困惑することがある. このため循環血液量測定の意義自体に疑問を抱く人も少なくない. 測定値の変動および誤差は放射性同位元素取扱い上の不注意に基因する以外に, 循環動態の変動が希釈計算式上十分に反映されていないために生ずる場合もまれではない. Gregersenはとくにこの点に重点をおき, 循環血液量測定時のmethodologyへの反省を強調している. 最近のようにautomatic computorにより血液量を測定する方法が普及し, 臨床目的と称し簡易化の傾向が見られるさい, methodologyの再検討を加えることも意義あるかと思考する, あわせて, 現在までに経験した約35,000例の測定結果を比較検討し, 従来の計算式に若干の変革を試みた. なお, 本論文では放射性同位元素の取扱上の不注意に起因する問題は除外した. |
|---|
| Practice | 臨床医学：一般 |
|---|
| Keywords | |
|---|
| English |
|---|
| Title | Problems in Measurements of Circulating Blood Volume |
|---|
| Subtitle | |
|---|
| Authors | Jo Shibuya, S.N.Albert, C.A.Albert, Yoshihiro Hiramatsu |
|---|
| Authors(kana) | |
|---|
| Organization | Anesthesiology Research Laboratory, Washington Hospital Center |
|---|
| Journal | The Japanese Journal of nuclear medicine |
|---|
| Volume | 2 |
|---|
| Number | 3/4 |
|---|
| Page | 166-172 |
|---|
| Year/Month | 1965/12 |
|---|
| Article | Original article |
|---|
| Publisher | THE JAPANESE SOCIETY OF NUCLEAR MEDICINE |
|---|
| Abstract | [Summary] Some investigators claim the blood volume measurements are meaningless and the results are unrelated with the clinical pictures. In order to clarify the underlying difficulties of blood volume measurements, critical analysis of 35,000 cases done at our laboratory was made. Blood volume is measured indirectly by determing the extent of dilution of a tracer with the intravascular content. By utilizing a single tracer either red cell or plasma volume is primarily measured, and the dilution ratio obtained dose not represent blood volume. The hematocrit indicates the volume red cells occupy in the sample of blood drawn from a peripheral vessel. The hematocrit of the blood sample does not reflect the actual cellular proportion of blood found in different parts ot the vascular bed. In minute vessels, the hematocrit is low and in larger vessels it is higher. Under normal conditions, the average hematocrit throughout the body is 91 per cent of the hematocrit obtained on a blood sample removed by venipuncture. This factor of 91 per cent (F cell ratio 0.91) varies between 0.70-1.20 under different conditions. The result obtained in our recent study on 200 blood volume determinations in patients of various conditions by means of dual tracers have shown that F cell ratio varied between 0.875 and 0.999 in 170 cases, and overrall average 0.915. The per cent error of blood volume, red cell volume and plasma volume calculated on the basis of a single tracer, taking into account an F cell ratio of 0.915 was negligible. In 91 per cent of the cases it ranged between +- 2.5 per cent. One of the basic principles involved in measuring blood volume is to obtain an equilibrated, well mixed sample. This is particularly important and most often encountered when labeled red cells are administered as a tracer material. In most instances mixing is complete within 10 minutes, but more frequently than anticipated, equilibration time s substantially prolonged, and one can not depend on the concentration of the tracer obtained on a single sample arbitrarily at 10 or 15 minutes time interval following the administration of a tracer. In conditions where ventilation is depressed, when blood-viscosity is elevated, under hypothermia, in dehydration, in shock, in a marked vasodilatation, when blood shunts exist, equilibration time is prolonged. Therefore, the calculation should be based on two or three different samples taken at different time. Labeled albumin normally is lost from intravascular bed at a slow rate 10 per cent per hour. But from our study, the rate of loss from the intravascular bed of the labeled albumin may vary from 10 to 30 per cent per hour. Therefore, calculation should not be based on a single sample at a fixed time interval following injection. To correct for this variable, one should establish the rate of the albumin tracer elimination and establish a corrected concentration at zero time before loss. For this purpose, it it necessary to plot the concentration of the labeled albumin tracer in blood versus time on semi-logarithmic paper and extrapolate the decay curve back to zero time; the sample taken at 7.5 and 15 minutes intervals seem to adequately reflect the rate of elimination. When total blood volume is calculated by albumin labeled tracer, here again hematocrit of the blood sample must be corrected by F cell ratio; in this case by Dilution factor (DF). To accurately measure total blood volume, the cellular and plasma elements of blood should be measured separately. For this purpose a dual tracer technique utilizing an albumin labeled tracer would measure plasma volume and labeled red cells will measure red cell volume. To avoid separation of plasma from cells and counting each separately 125I and 51Cr labeled cells can be utilized together and counted separately in the presence of each other in a mixed sample of blood by means of discriminating pulse hight analyzer. |
|---|
| Practice | Clinical medicine |
|---|
| Keywords | |
|---|