Länne T, Lundvall J
Department of Clinical Physiology, Växjö Hospital, Sweden.
Acta Physiol Scand. 1989 May;136(1):1-6. doi: 10.1111/j.1748-1716.1989.tb08623.x.
High levels (110-120 cmH2O) of lower body negative pressure (LBNP) were used in male volunteers (n = 7) to produce pronounced hypovolaemic circulatory stress in an attempt to reveal the potential in man for compensatory absorption of extravascular fluid from skeletal muscle and skin as studied in the upper arm by plethysmographic technique. LBNP evoked clear-cut hypovolaemic symptoms or even accidental syncope as well as a marked tachycardiac response and a significant fall in systolic blood pressure. In the studied arm there was concomitantly a very rapid net transcapillary absorption of extravascular fluid into the circulation at an average rate of 0.35 ml min-1 100 ml-1 soft tissue during 5 min of LBNP exposure. These data demonstrate an amazingly great potential to increase plasma volume by 'autotransfusion' of fluid from tissue to blood, as may be visualized by extrapolation of the data from the arm to apply to the whole mass of skeletal muscle and skin in the body. The observed absorption rate would then correspond to a total fluid gain of no less than 700 ml within a period no longer than 5 min. At present, however, there is no evidence to indicate that such impressive fluid volumes can be rapidly transferred from the extra-to the intravascular space after actual blood loss.
对7名男性志愿者施加高水平（110 - 120 cmH₂O）的下体负压（LBNP），以产生明显的低血容量循环应激，试图揭示人体从骨骼肌和皮肤中代偿性吸收血管外液的潜力，这是通过体积描记技术在上臂进行研究的。LBNP引发了明确的低血容量症状甚至意外晕厥，以及明显的心动过速反应和收缩压显著下降。在接受研究的手臂中，在LBNP暴露5分钟期间，血管外液以平均0.35 ml·min⁻¹·100 ml⁻¹软组织的速率非常迅速地通过毛细血管净吸收进入循环。这些数据表明，通过将组织中的液体“自体输血”到血液中来增加血浆量的潜力惊人地大，这可以通过将手臂的数据外推应用于身体的整个骨骼肌和皮肤质量来直观呈现。然后观察到的吸收率将对应于在不超过5分钟的时间内总液体增加量不少于700 ml。然而，目前没有证据表明在实际失血后，如此大量的液体能够迅速从血管外转移到血管内空间。
