The Influence of Prolonged Inspiratory Time on Respiratory Mechanics and Oxygenation in Obese Patients Undergoing Spine Surgery in the Prone Position
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 50
- 试验地点
- 2
- 主要终点
- PaO2(Partial Pressure of Oxygen in Arterial Blood)
研究概览
简要总结
The area of aesthesia-induced atelectasis is much larger in the obese compared with the non-obese, but there may also be more airway closure and impaired matching of ventilation and lung blood flow.
When an anesthetized patient is turned to the prone position, dynamic compliance (Cdyn) decreases and peak airway pressure increases unless the abdomen hangs freely to prevent the abdominal viscera from compromising the diaphragm movement. Although the Wilson frame is designed to allow the abdomen to hang, it partially compresses the anterior abdominal wall and therefore does not allow the abdomen to hang completely, especially in obese patients.
This in turn increases peak airway pressure and decreases Cdyn, oxygenation. This study aimed to investigate the effects of a prolonged I:E ratio (i.e., 1:1) compared with the conventional I:E ratio of 1:2 on respiratory mechanics and hemodynamics during spine surgery in the prone position in obese patients.
We hypothesized that, compared with an I:E ratio of 1:2, a ratio of 1:1 improve oxygenation without hemodynamic instability .
详细描述
After written informed consent was obtained from all patients, 50 adult patients were enrolled in the study.
The patients met the following inclusion criteria: (1) body mass index (BMI, weight in kilograms divided by the square of height in metres) > 25 kg/m2; (2) American Society of Anesthesiology (ASA) physical status classification grade I or II (BMI by itself was not used as the basis for the ASA classification); (3) aged 20 - 65 years; and (4) scheduled for elective spine surgery in prone position.
Exclusion Criteria:
- Patients who have severe pulmonary disease:
history of chronic obstructive pulmonary disease (COPD), asthma, or pneumothorax. Patients with haemodynamic instability, hypovolaemia, bronchopleural fistula, The enrolled patients were randomly allocated according to a predetermined allocation sequence to receive an I:E ratio of either 1:1 (group 1:1) or 1:2 (group 1:2).
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- None
入排标准
- 年龄范围
- 20 Years 至 65 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •ASA I-II adult patients scheduled for spine surgery under general anesthesia.
- •patient age : greater than 20 years and less than 65years
- •Body Mass Index(BMI) >25 kg/m2
排除标准
- •Patients who have severe pulmonary disease:
- •history of chronic obstructive pulmonary disease (COPD), asthma, or pneumothorax. Patients with haemodynamic instability, hypovolaemia, bronchopleural fistula, history of cardiopulmonary disease, or previous lung surgery are excluded.
结局指标
主要结局
PaO2(Partial Pressure of Oxygen in Arterial Blood)
时间窗: ten minutes after tracheal intubation to 90 min after prone position
ten minutes after tracheal intubation to 90 min after prone position
次要结局
未报告次要终点
研究者
Jung Ju Choi
assistance professor
Gachon University Gil Medical Center