Experimental Localization of flow Limiting Segment

Flow limitation이 일어나는 기도내 위치의 실험적 측정

  • 차은종 (충북대학교 의과대학 의공학교실) ;
  • 이태수 (충북대학교 의과대학 의공학교실, 생리학교실, 외과학교실)
  • Published : 1992.09.01

Abstract

A new experimental technique is proposed to localize the flow limiting segment(FLS) during forced expiration. The present technique is based on the pressure drip across FLS and a consequent change in airway resistance, which can provide an accurate and objective location of FLS. During forced expiratory maneuver artificially induced by a strong negative pressure (-100mmHg) applied at the trachea in an anesthetized open chest dog, airway resistance( R) was calculated from air flow and airway pres- sure signals at various airway locations and lung volumes, At the lung volumes above 10 % VC, FLS located in the trachea 6cm lower from the larynx. With the lung volume decreased below 8% VC, FLS jumped upstream to End-3rd generation of the airway. These results were similar with the previous reports from excised dog lungs, which demonstrated the validity of the present technique. Since the present technique provides a more objective measure of FLS location, it would be useful in future studies of expiratory flow limitation.

Keywords

References

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