Medical blood oxygenator

Hollow fiber refers to a membrane tube of very small diameter (e.g., 200 pm). Such small diameters enable a large membrane area per unit volume of device, as well as operation at somewhat elevated pressures. Hollow-fiber modules are widely used in medical devices such as blood oxygenators and hemodialyzers. The general geometry of the most commonly used hollow-fiber module is similar to that of the tubular membrane, but hollow fibers are used instead of tubular membranes. Both ends of the hollow fibers are supported by header plates and are connected to the header rooms, one of which serves as the feed entrance and the other as the retentate exit. Another type of hollow-fiber module uses a bundle of hollow fibers wound spirally around a core. 

Six developed and a number of developing and yet-to-be-developed industrial membrane technologies are discussed in this book. In addition, sections are included describing the use of membranes in medical applications such as the artificial kidney, blood oxygenation, and controlled drug delivery devices. The status of all of these processes is summarized in Table 1.1. 

In this chapter, the use of membranes in medical devices is reviewed briefly. In terms of total membrane area produced, medical applications are at least equivalent to all industrial membrane applications combined. In terms of dollar value of the products, the market is far larger. In spite of this, little communication between these two membrane areas has occurred over the years. Medical and industrial membrane developers each have their own journals, societies and meetings, and rarely look over the fence to see what the other is doing. This book cannot reverse 50 years of history, but every industrial membrane technologist should at least be aware of the main features of medical applications of membranes. Therefore, in this chapter, the three most important applications—hemodialysis (the artificial kidney), blood oxygenation (the artificial lung) and controlled release pharmaceuticals—are briefly reviewed. 

This membrane industry is very fragmented. Industrial applications are divided into six main sub-groups reverse osmosis ultrafiltration microfiltration gas separation pervaporation and electrodialysis. Medical applications are divided into three more artificial kidneys blood oxygenators and controlled release pharmaceuticals. Few companies are involved in more than one sub-group of the industry. Because of these divisions it is difficult to obtain an overview of membrane science and technology this book is an attempt to give such an overview. 

Medical applications are among the most important in the membrane market, with hemodialysis, blood oxygenators, plasma separation and fractionation being the traditional areas of applications, while artificial and bioartificial organs and regenerative medicine represent emerging areas in the field. 

When Howard went to the emergency room with a potential heart attack, the medical team looked carefully at his heart rate, his breathing, what his blood oxygen levels were, and his overall coherency. 

In recent years, a large number of papers have been published on cranial blood oxygenation [51-72], Oxygenation in general has been a major focal point for NIR medical research [73-87]. It continues to be a successful application for NIR. 

Nitrogen.—Amines, Enamines, Imines, Oximes, Isocyanates, Cyanides, and Related Compounds. Perfluorotributylamine, (C4F9)sN (FCM3 ), has continued to feature in work on medical applications (blood oxygenation etc.) of fluorocarbon-type... 

Pulse oximetry can be integrated into wearable sfructure with woven or embroidered POF textile structures such as a glove or patch for a LED/photodiode sensor together with microcontroller connection. The blood oxygen saturafion (Sa02) data can be interfaced to the WBSN and transferred to the data sink in medical offices for further interpretation and timely intervention. Textile biosensors considered above for WBSN based on E-Tex are summarized in Table 9.2. These textile sensors are flexible and provide good connectivity for integration of E-Tex and body sensor networks. 

The applications of PCs are extensive, emanating into all types of markets. A sample would include electronic connectors, switches, terminal blocks, computer disc packs, storage modules and housings, appliance power-tool housings, vacuum cleaner impellers, fan and air-conditioner grills, automotive instrument panels, indoor and outdoor lighting diffusers, medical kidney dialysers and blood oxygenators, and a host of others. 

Today membranes play a dominant role in medical applications such as artificial kidney and blood oxygenator capillary. 

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