Glahn B E
Department of Urology, Glostrup Hospital, University of Copenhagen, Denmark.
Scand J Urol Nephrol. 1988;22(2):87-92. doi: 10.1080/00365599.1988.11690391.
Clinical observations suggest the occurrence of a hydro-dynamically generated negative pressure wave in termination of bladder evacuation in patients with an intermittently clamped indwelling catheter. This in-vitro study confirmed the assumption. At circumstances like those of a bedridden person with a conventional urinary drainage system the transitory suction at the site of the catheter eyes reaches negative peak pressures of about 150-180 cm of water when catheters on a latex base are used and about 300-350 cm by catheters of 100% silicone, which is a less compliant (elastic) material. Catheters, drainage tubes and the combined function were analyzed regarding factors influencing this hydro-dynamical phenomenon, which may occur in some situations of straight drainage too. Clinical aspects are discussed. A noxious effect on the bladder mucosa is demonstrated in a subsequent study. It is concluded that the basal hydro-physical laws involved in bladder drainage by indwelling catheter need more attention.
临床观察表明，对于间歇性夹闭留置导尿管的患者，膀胱排空结束时会出现流体动力学产生的负压波。这项体外研究证实了这一假设。在使用传统尿液引流系统的卧床患者的情况下，当使用乳胶材质的导尿管时，导管眼处的瞬时吸力会达到约150 - 180厘米水柱的负压峰值；而使用100%硅胶材质（一种顺应性较差的（弹性）材料）的导尿管时，该负压峰值约为300 - 350厘米水柱。针对影响这种流体动力学现象的因素，对导尿管、引流管及其综合功能进行了分析，这种现象在一些直排情况下也可能发生。文中还讨论了临床方面的问题。后续研究表明这种现象对膀胱黏膜有不良影响。得出的结论是，留置导尿管进行膀胱引流所涉及的基本流体物理规律需要更多关注。
