Coulthard M G, Sharp J
Department of Paediatric Nephrology, Royal Victoria Infirmary, Newcastle upon Tyne, NE1 4LP, UK.
Pediatr Nephrol. 2001 Apr;16(4):332-4. doi: 10.1007/s004670000547.
Haemodialysing small infants is difficult because of vascular access limitations. We show that Poiseuille's law (that flow through a tube varies with its radius4) makes it inevitable that the blood flow that can be achieved in smaller patients will fall disproportionately compared to their need for dialysis. Poiseuille's law also predicts that for single and multiple lumen cannulae of the same outside gauge, blood flow through the single lumen will be several times greater. Measurements confirmed this. It is argued that haemodialysis efficiency will therefore be improved by using a single lumen cannula to alternately withdraw and return blood, compared to sampling and returning continuously through a multiple lumen cannula, despite only withdrawing for half the time.
由于血管通路受限，对小婴儿进行血液透析很困难。我们发现泊肃叶定律（即通过管道的流量随其半径的四次方变化）使得较小患者所能实现的血流量与其透析需求相比将不成比例地下降成为必然。泊肃叶定律还预测，对于相同外径规格的单腔和多腔插管，通过单腔的血流量将大几倍。测量结果证实了这一点。有人认为，因此与通过多腔插管持续采样和回血相比，使用单腔插管交替抽血和回血，尽管仅在一半时间内抽血，但血液透析效率将得到提高。
