Mechanisms of Orthopnea in Stable Obese Patients
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 30
- 试验地点
- 2
- 主要终点
- closing volume by nitrogen washout method
研究概览
简要总结
The purpose of this study is to study the role of closing volume as a determinant of orthopnea in stable obese subjects. The investigators hypothesized that: (1) increase in closing volume in supine position would be greater in orthopneic than in non-orthopneic subjects, and (2) the relationship of change in closing volume to change in dyspnea with position would be dependent on expiratory flow limitation in the sitting position.
In stable obese subjects, in sitting and supine positions, the investigators measured Borg dyspnea score, static lung volumes, expiratory flow limitation, and single-breath nitrogen expiration test, from which the investigators determined closing volume and closing capacity, slope of phase III, and opening capacity.
Orthopnea was defined as any increase in the Borg score in the supine position from its value in the sitting position
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Diagnostic
- 盲法
- None
入排标准
- 年龄范围
- 20 Years 至 60 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •obese (BMI ≥ 30)
- •stable condition
- •20 < Age < 60 years
排除标准
- •other respiratory disorder (COPD)
- •left cardiac insufficiency
研究组 & 干预措施
sitting position
measurement in the sitting position
supine position
measurement in the sitting position
干预措施: Supine (Other)
结局指标
主要结局
closing volume by nitrogen washout method
时间窗: 30 minutes after changing position (hour 2)
次要结局
- static lung volumes by plethysmography(30 minutes after changing position (hour 2))
- expiratory flow limitation by NEP test(30 minutes after changing position (hour 2))