Improving the efficiency of a tubular membrane oxygenator.

The development of a tubular membrane oxygenator is described. Fine silicone rubber tubes are inserted into a large silicone rubber tube and sealed. Oxygen is blown through the fine tubes, blood flows through the large tube, and the gases are exchanged through the wall of the fine tubes. The efficiency of the device is improved by increasing the gas pressure, which is followed by bubble formation in the blood, and which is therefore unacceptable. By arranging the inside tubes in a wavy pattern and by repeatedly stretching them the efficiency is increased without side effects.