[Oxygen-conserving delivery system]

Three methods for improving oxygen delivery efficiency--transtracheal oxygen therapy (TTO), reservoir cannula, and demand-pulse oxygen delivery--are currently available. We discuss our experiences of TTO and its characteristics compared with the other two methods. Since 1988, we have tried to apply TTO to the candidates for home oxygen therapy (HOT) fulfilling the following criteria: 1) good activity and enthusiasm to daily life, 2) high oxygen flow rate with nasal cannula, 3) complicating nasal disorders such as chronic sinusitis, or 4) suffering complications from nasal cannula therapy. We used a disposable 8-Fr feeding tube for a trnastracheal catheter. Patients were taught to change their catheters themselves every day by simply removing the old and reinserting the new catheter. We have experienced nine patients on HOT with TTO. A half to a third of the flow rate of nasal cannular was required with TTO to achieve an equivalent PaO2 level. In cases with hypercapnea, a persistent significant increase of PaCO2 was not found. We measured arterial blood gases, changing the distance from the tract opening to the catheter tip, and it was suggested that in each case there may be an optimum distance to achieve the highest PaO2 level. Seven cases received TTO for more than 18 months, a mean of 30.2 months (range 19.3-48.9) and HOT for a mean of 26.6 months. They all maintained a high degree of enthusiasm for TTO. Two cases could return to work. Five cases enjoyed active daily lives, such as shopping, going out for recreation, travelling, and attending concerts.(ABSTRACT TRUNCATED AT 250 WORDS)