Study of the proper management of total liquid ventilation and the development of the system for respiratory suport
Grant-in-Aid for Scientific Research (A)
|Allocation Type||Single-year Grants |
|Research Institution||National Cardiovascular Center Research Institute |
TAKANO Hisateru Deputy General Manager, National Cadiovascular Center Research Institute, 副所長 (60028595)
TSUKAHARA Kinji Researcher, Aisin Cosmos R&D Co., Ltd, 研究員
MASUZAWA Toru Researcher, Dept. of Artificial Organs, Natl Cardiovasc Ctr Res Ins, 人工臓器部, 室長 (40199691)
TASTUMI Eisuke Deputy General Manager, Dept. of Artif Organs, Natl Cardiovasc Ctr Res Ins, 人工臓器部, 室長 (00216996)
NAKATANI Takeshi Deputy General Manager, Dept. of Bioengineering, Natl Cardiovasc Ctr Res Ins, 生体工学部, 室長 (60155752)
TAENAKA Yoshiyuki General Manager, Dept. pf Artifical Organs, Natl Cadiovasc Ctr Res Ins, 人工臓器部, 部長 (00142183)
馬塲 雄造 国立循環器病センター研究所, 人工臓器部, 室員 (50270731)
|Project Period (FY)
1994 – 1996
Completed (Fiscal Year 1996)
|Budget Amount *help
¥33,000,000 (Direct Cost: ¥33,000,000)
Fiscal Year 1996: ¥5,700,000 (Direct Cost: ¥5,700,000)
Fiscal Year 1995: ¥7,300,000 (Direct Cost: ¥7,300,000)
Fiscal Year 1994: ¥20,000,000 (Direct Cost: ¥20,000,000)
|Keywords||Liquid Ventilation / Lipuid breathing / perfluorocarbon / perfluorochamical / perfluorochemical / Liquid / Ventilation / Breathing / Perfluorocarbon|
1. Initially, a liquid ventilator was developed which was controlled by volume-controlled with pressure limit mode, and total liquid ventilation was performed with it in rabbits. End-expiratory residual volume (EERV) was proved too excessive during total liquid ventilation at initial experiment when compared with the pressure-volume courve of perfluorocarbon measured with others rabbits.
2. Weight-controlling total liquid ventilation with rabbits was carried out. The principal of this ventilation to regulate a tidal volume and the EERV was as follows ; the density of PFC is large and the weight of a liquid ventilated animal varies. Therefore, if a maximum and minimum weight are controlled, it follows that a TV and EERV can be controlled. The EERV was increased during liquid ventilation, but TV and ventilation cycle were kept the same. There was no change in PaO2, SaO2, and hemoglobin concentration, whereas PaCO2 and SvO2 deteriorated as the EERV increased. That is, increase in EERV harm
s gas exchange as well as circulation. The most physiological level of the EERV was around functional residual capacity of liquid (FRC of liquid : FRCL).
3. However, to reach the EERV of ERCL with relatively short time was very difficult. Expiration of PFC needs drawing force due to low recoil property. With conventional expiration such as siphon, troughs appear during expiration. These troughs seem to be caused by airway occlusion which may cause airway bleeding or uneven ventilation. We developed a new expiratory method in which difference for siphon became rapidly smaller as the expiration. Rather smooth expiration became feasible with the method.
4. Total liquid ventilation with rabbits was carried out with this method on the condition that the EERV was lept as FRCL and a TV was kept constant small volume, but ventilation rate varied. The PaO2 and PaCO2 improved rate-responsively without metabolic acidosis.
5. Total liquid ventilation with rabbits was considered that it was impossible to keep both PaCo2 and SvO2 physiologically. The research proved that there was a possibility that the total liquid ventilation could be maintained in difficult cases such as rabbits, and that the results might deny the conventional view for total liquid ventilation : total liquid ventilation must be maintained with large TV and small rate. Less
Report (4 results)
Research Products (15 results)