There has been recent interest in increasing the efficiency of oxygen delivery in an effort to improve the portability of ambulatory oxygen and to reduce the cost of oxygen therapy. Oxygen-conserving devices designed to meet these needs are TTO catheters, electronic pulsed DODS and reservoir cannulas. In addition to oxygen conservation, transtracheal oxygen therapy has other inherent advantages which render it particularly attractive, including improved cosmesis, compliance and avoidance of the nasal and auricular irritation frequently experienced with the standard nasal cannula.
All three devices have been shown to achieve adequate Sa02 while reducing the per-minute requirement for supplemental oxygen by a factor of 2 to 7 as compared with continuous flow nasal oxygen. Increases in efficiency might translate to reduced cost of portable oxygen. The oxygen-conserving devices were designed based on the theory that maximal efficiency is gained by delivering oxygen as early as possible in the inspiratory phase. However, this concept has not been tested. It also has been speculated that efficiency of TTO delivery could be improved by combining TTO with electronic pulsed demand oxygen delivery technologies. buy levitra professional
The purpose of this study was to investigate both of these concepts. The effect of various delays between the beginning of inspiration and initiation of the oxygen pulse was evaluated with nasal and transtracheal oxygen delivery. Furthermore, the efficiency of pulsed TTO therapy was compared with continuous flow transtracheal delivery.