Oxygen Consumption and Sevoflurane Uptake Based on Physiological Dead Space Estimation During Closed Circuit Anesthesia: A Prospective Interventional Study
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 17
- 试验地点
- 2
- 主要终点
- Change in Fe.sevo during the closed-circuit ventilation mode
研究概览
简要总结
In this study, the investigators will evaluate whether the delivered fraction of oxygen (O2) and sevoflurane administered through a a closed circuit and calculated on the basis of the estimations of O2 consumption (VO2) and sevoflurane uptake (SEVOup) through the inspired-expired fraction gradients of both gases once subtracted the physiological dead space (VDphys), adequately fits the real gases consumption. All participants will be ventilated under a tailored open lung approach (tOLA) strategy.
详细描述
The "quantity" of the lung that participates in gas exchange in anesthetized and mechanically ventilated patients varies depending on individual conditions. This "part" of the lung that is responsible for "breathing" is referred as the respiratory volume in contrast to that "part" or volume of the lung that is in charge of driving the air towards the respiratory zones: the trachea, bronchi, et cetera, which do not directly participate in breathing. This conduction volume, together with that alveolar volume excluded from gas exchange due to different circumstances, constitutes the physiological dead space (VDphys), which represents the percentage of tidal volume that does not participate of respiration. The VDphys can be estimated by different means.
Knowing the VDphys will allow the clinicians to more precisely adjust the amount of oxygen and anesthetic gas (sevoflurane) to be supplied to the anesthesia workstation when working in a closed circuit mode, given that the estimations of VO2 and SEVOup, and consequently of the milliliters of oxygen and sevoflurane to supply per minute (DO2 and SEVOsuppl, respectively), are calculated in the basis of the "respiratory" volume rather that in the "total" tidal volume (TV); this is, taking in consideration the VDphys/TV ratio.
In this work, the investigators will evaluate the accuracy in estimating VO2 and SEVOup taking into consideration the VDphys/TV ratio when working with a closed circuit mode of anesthesia administration. The investigators will study the relationship between the DO2 and SEVOsuppl, calculated based on VDphys/TV ratio, and the real consumption of O2 and sevoflurane measured through the gas analyzer of the anesthesia workstation.
Methods
This one-arm interventional study corresponds to phase 3 of the study "Influence of Inspiratory Pause on Ventilatory Efficiency in Robotic Surgery. A Prospective Paired Study". Participants will be consecutively recruited among those patients submitted to prostatic robotic surgery, once obtained the corresponding informed consent. The study will be carried out in a tertiary care teaching hospital (Hospital Universitario Virgen del Rocío). Approval for this study will be sought from the local ethics committee. The recruitment will be made on investigators availability.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 99 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Adult subjects (≥ 18 years) scheduled for robotic prostatic surgery at the investigators´ institution
- •Written informed consent
排除标准
- •Participation in another interventional study
- •Participants unable to understand the information contained in the informed consent
- •American Society of Anesthesiologists (ASA) classification grade = IV
- •Patient in dialysis
- •Chronic obstructive pulmonary disease (COPD) grade Global Initiative for Chronic Obstructive Lung Disease(GOLD) > 2
- •Functional vital capacity < 60% or > 120% of the predicted
- •Body mass index (BMI) > 35 kg/m2
- •Relation arterial pressure of oxygen (PaO2)/FiO2 <200 mmHg in the baseline sample
- •Presence of mechanical ventilation in the 72 hours prior to enrollment
- •New York Heart Association (NYHA) functional class ≥ 3
- •Clinically suspected heart failure
- •Diagnosis or suspicion of intracranial hypertension
- •Presence of pneumothorax or giant bullae on preoperative imaging tests
- •Use of Continuous Positive Airway Pressure (CPAP).
结局指标
主要结局
Change in Fe.sevo during the closed-circuit ventilation mode
时间窗: Intraoperative (From the beginning of the maintenance phase of the anesthesia , with recording every 10 minutes or at any time if a deviation of the end-tidal fraction of sevoflurane higher than 5% of the estimated value is detected)
Any deviation of the expired fraction of sevoflurane (Fe.sevo) with respect to the reference value (this calculated based on SEVOup.alv estimation). The investigators will reflect this potential deviation through time.
Change in FeO2 during the closed-circuit ventilation mode
时间窗: Intraoperative ( From the beginning of the maintenance phase of the anesthesia , with recording every 10 minutes or at any time if a deviation of the end-tidal fraction of O2 higher than 5% of the estimated value is detected)
Any deviation of the expired fractions of O2 (FeO2) with respect to the reference value (this calculated based on VO2.alv estimation). The investigators will reflect this potential deviation through time.
次要结局
未报告次要终点