Blood oxygenator design

R. G., Weatherley, B.C., White, R.D., WOOTTON, R. The effects in volunteers of BW12C, a compound designed to left-shift the blood-oxygen saturation curve. Br. J. Clin. Pharmacol. 1985, 19, 471-481. 

In recent years, many investigations have been conducted, including clinical trials, with bioartificial fiver devices using either animal or human liver cells. Likewise, many reports have been made with various designs of bioartificial fiver device [19]. However, there are no established fiver support systems that can be used routinely in the same way as hemodialyzers or blood oxygenators. Today, bioartificial fiver devices can be used to assist the fiver functions of patients with fiver failure on only a partial and/or a temporary basis. Moreover, none of these devices can excrete bile, as does the human fiver. 

Arunachalam VM and Shettigar UR. Bubble blood oxygenator—a design analysis. Arm. Biomed Eng. 1981 9 75-87. 

Wickramasinghe SR and Han B. Designing microporous hollow fibre blood oxygenators. Chem. Eng. Res. Des. 2005 83(A3) 256-261. Catapano C, Papenfuss HD, Wodetzki A, and Baurmeister U. Mass and momentum transfer in extra-luminal flow (ELF) membrane blood oxygenation. J. Membr. Sci. 2001 184 123-135. 

Fig. 48. Flow schematic of a membrane blood oxygenator. The device is designed to deliver about 250 cm (STP)/min of oxygen to the blood and remove about 200 cm (STP)/min of carbon dioxide from the blood.

P. Fitzharris, A. E. M. McLean, R. G. Sparks, B. C. Weatherley, R. D. White, and R. Wootton, Br. J. Clin. Pharmacol., 19, 471 (1985). The Effects in Volunteers of BW12C, a Compound Designed to Left-Shift the Blood-Oxygen Saturation Curve. 

Route of Exposure. A toxin may enter the body in several ways. It may be ingested or inhaled, it may come into contact with the skin or eyes, or it may be administered by injection (typically intravenous, intramuscular, or subcutaneous injection). In occupational settings, the major routes of exposure which are of most concern are inhalation and contact. The lungs have an extensive blood supply designed for efficient absorption of oxygen and, therefore, toxins which enter the lungs by inhalation may easily reach the body s blood supply such toxins may, of course, also have local effect on the respiratory system. Similarly, the eyes have an extensive blood supply and may be a source of concern for systemic absorption as well as local effect. 

Here (v) is the observable transmembrane solvent velocity, and P is the membrane solute diffusional permeability. The permeability in turn is defined as the ratio of the molar flux of solute transport, moles/area-time, to the solute concentration difference causing this transport The most familiar examples of low-Pe devices are blood oxygenators and hemodialyzers. High-Pe systems include micro-, ultra-, and nano-filtration and reverse osmosis. The design and operation of membrane separators is discussed in some detail in standard references [Ho and Sirkar, 1992 Noble and Stern, 1995], and a summary of useful predictions is provided in Section 5.4. 

It may not be out of place to mention that porous hydrophobic hollow fiber membrane devices having various designs are used etctensively as membrane oxygenators or blood oxygenators. Air as a source of oxygen is supplied through the bore of the hollow fibers while blood flows on the outside of the fibers the blood is supplied with O2 while CO2 in the blood is stripped into the air stream. 

Mortensen, J.D. and Berry, G. 1989. Conceptual and design features of a practical, clinically effective intravenous mechanical blood oxygen/carbon dioxide exchange device (Ivox). Int J Artif Organs 12(6) 384-9. 

Fig. 9.4-1. The Graetz-Nusselt problem. In this case, a pure solvent flowing laminarly in a cylindrical tube suddenly enters a section where the tube s walls are dissolving. The problem is to calculate the wall s dissolution rate and hence the mass transfer coefficient. The problem s solutions, based on analogies with heat transfer, are useful for designing artificial kidneys and blood oxygenators.

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