Does Pulmonary Compliance Optimization Through PEEP Manipulations Reduces the Incidence of Postoperative Hypoxaemia in Bariatric Surgery?
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 100
- 试验地点
- 2
- 主要终点
- Number of hypoxemia episodes (Sp02<90%)
研究概览
简要总结
General anesthesia, even in patients in good health, impairs gas exchanges and ventilatory mechanics. These effects result primarily from atelectasis formation. They occur in 85-90% of healthy patients in the minutes following the induction when a positive end expiratory pressure (PEEP) is not used.
The functional residual capacity (FRC) of obese patients during general anesthesia is even smaller than the one of healthy patients. There is a direct relationship between the body mass index and the decrease of the functional residual capacity. Obese patients have therefore more atelectasis. The increased abdominal pressure during the pneumoperitoneum will increase the decrease of the CRF, and thus aggravate the formation of these atelectasis.
Atelectasis affect the peroperative gas exchanges and are likely to be involved in the worsening of postoperative hypoxemia episodes. In addition, atelectasis alter the clearance of secretions and the lymph flow, which predispose to lung infections.Taking all these factors into account, it is logical to think that the atelectasis presence can lead to an increase of the postsurgical morbidity (respiratory distress, infections). That is why actively fighting against the formation of these atelectasis is important.
There is a lack of scientific evidence to say that the strategies against atelectasis as PEEP have a significant impact on the patient's postoperative status. The expected clinical benefits balance (reduction of respiratory distress episodes, infections and mortality) versus the risks linked to the maneuvers done to reduce the development of atelectasis (barotraumas, cardiac complications) remains to be determined.
The primary goal of this study is to evaluate the impact of two different alveolar recruitment strategies on the incidence of postoperative hypoxemia in obese patients after bariatric surgery.
The secondary objectives of this study are to compare the number of recruitment maneuvers, the Pa02 / FI02 ratio (ratio of arterial oxygen partial pressure to fractional inspired oxygen), the dynamic compliance, the anatomic dead space and intraoperative PaCO2-EtCO2 gradient (arterial and end tidal gradient) between two alveolar recruitment strategies applied in obese patients during laparoscopic bariatric surgery (gastric bypass or sleeve gastrectomy).
The tertiary objectives of this study are to report the number of respiratory complications and postoperative wound infections at the 30th postoperative day.
详细描述
General anesthesia, even in patients in good health, impairs gas exchanges and ventilatory mechanics. These effects result primarily from atelectasis formation. They occur in 85-90% of healthy patients in the minutes following the induction when a positive end expiratory pressure (PEEP) is not used.
These atelectasis are formed on one hand by the reduction of the functional residual capacity (FRC) following a compression mechanism (loss of the inspiratory muscle tone, which is accompanied by a chest wall configuration change and a diaphragm cephalic movement) and on the other hand by a denitrogenation absorption process (ventilation at high Fi02 (oxygen inspired fraction) causing complete absorption of O2 with lack of support for the alveolus, which then collapses).
The FRC of obese patients during general anesthesia is even smaller than the one of healthy patients. There is a direct relationship between the body mass index and the decrease of the functional residual capacity. Obese patients have therefore more atelectasis. The increased abdominal pressure during the pneumoperitoneum will increase the decrease of the CRF, and thus aggravate the formation of these atelectasis.
Atelectasis affect the peroperative gas exchanges and are likely to be involved in the worsening of postoperative hypoxemia episodes. In addition, atelectasis alter the clearance of secretions and the lymph flow, which predispose to lung infections.Taking all these factors into account, it is logical to think that the atelectasis presence can lead to an increase of the postsurgical morbidity (respiratory distress, infections). That is why actively fighting against the formation of these atelectasis is important.
Several strategies have been studied in order to improve respiratory mechanics and reduce impaired gas exchange during laparoscopic surgery in obese patients. The position called "chair", mechanical ventilation with PEEP, recruitment maneuvers followed by the PEEP, and spontaneous ventilation with CPAP before extubation, are all strategies that have proven effective to decrease development these atelectasis.
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
- Double (Participant, Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 65 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •ASA score (American Society of Anesthesiologists ) of II or III
- •BMI > 35 kg/m²
- •Elective laparoscopic bariatric surgery: gastric bypass or sleeve
排除标准
- •Restrictive (CPT <65%) or obstructive (VEMS/CV < 69%) chronic lung disease
- •Increase of the intracranial pressure
- •History of smoking with chronic obstructive disease (VEMS/CV)
- •Active tabagism
- •Ongoing pregnancy
- •History of heart failure (NYHA III or IV) or coronary artery disease
- •Urgent surgery
- •Allergy to a drug used within the study
- •Lack of written informed consent
研究组 & 干预措施
PEEP 10 cmH20
In this group, a PEEP of 10 cmH20 is applied for the duration of the intervention and a recruitment maneuver is applied each time the SpO2 (oxygen pulsated saturation) drops below 95%.
干预措施: PEEP (positive end-expiratory pressure) (Device)
optimal PEEP
In this group, 10 cmH20 PEEP is applied immediately. Then the "optimal PEEP" is sought at three key moments. It is determined by the best value of lung compliance found in the patient. It is sought by increasing or decreasing the value of the PEEP by increments or decrements of 2 cmH20. If after 6 respiratory cycles, the value of the compliance is increased, the investigator continues to increase the value of the PEEP. On the other hand, if the value of compliance is reduced, the investigator reduces the value of PEEP. The value of the PEEP selected shall in no event exceed the set pressure range (maximum pressure plate of 30 cmH20 and maximum inspiratory peak pressure 40cmH20). A recruitment maneuver is applied each time the SpO2 drops below 95%, as in the PEEP 10cmH2O group.
干预措施: PEEP (positive end-expiratory pressure) (Device)
结局指标
主要结局
Number of hypoxemia episodes (Sp02<90%)
时间窗: continuously during 48h after surgery
This will be monitored by a portable saturometer (OxyTrue A, Bluepoint, Germany). This saturometer will allow the investigators to count the number of hypoxemia episodes (Sp02\<90%) and their duration in obese patients, in the postoperative period.
Number of hypoxemia episodes (Sp02<95%)
时间窗: continuously during 48h after surgery
This will be monitored by a portable saturometer (OxyTrue A, Bluepoint, Germany). This saturometer will allow the investigators to count the number of hypoxemia episodes (Sp02\<95%) and their duration in obese patients, in the postoperative period.
次要结局
- Pulmonary dynamic compliance (Cd) - moment 1(just after the anesthesia induction/intubation, patient laying flat, without pneumoperitory)
- Anatomic dead space -moment 1(just after the anesthesia induction/intubation, patient laying flat, without pneumoperitory)
- Anatomic dead space -moment 2(just after peritoneal insufflation and anti-trendenlenbourg (anti-trent) implementation)
- PaO2/FiO2 ratio - preoperative(Just before surgery, at ambient air contact)
- Number of recruitment manoeuvers(From moment 3 till the end of the surgery (patient leaving the theater))
- Pulmonary dynamic compliance (Cd) -moment 3(just after pneumoperitoneum exsufflation - patient lying flat)
- Pulmonary dynamic compliance (Cd) -if recruitment manoeuvers(Five minutes after any recruitment manoeuver)
- Anatomic dead space -moment 3(just after pneumoperitoneum exsufflation - patient lying flat)
- PaCO2-EtCO2 gradient - moment 1(just after the anesthesia induction/intubation, patient laying flat, without pneumoperitory)
- PaCO2-EtCO2 gradient - moment 2(just after peritoneal insufflation and anti-trendenlenbourg (anti-trent) implementation)
- PaCO2-EtCO2 gradient - moment 3(just after pneumoperitoneum exsufflation - patient lying flat)
- Number of respiratory complications(30 days after surgery)
- Pre-operative physiologic measures: partial pressure of carbon dioxide in the arterial blood (PaCO2)(Just before surgery, at ambient air contact)
- Operative physiologic measures - moment 1: FC(just after induction/intubation, patient laying flat, without pneumoperitoneum)
- Operative physiologic measures - moment 1: PaCO2(just after induction/intubation, patient laying flat, without pneumoperitoneum)
- Operative physiologic measures - moment 3: pH(just after pneumoperitoneum exsufflation - patient lying flat)
- Pulmonary dynamic compliance (Cd) - preoperative(Just before surgery, at ambient air contact)
- Pulmonary dynamic compliance (Cd) -moment 2(just after peritoneal insufflation and anti-trendenlenbourg (anti-trent) implementation)
- Anatomic dead space - preoperative(Just before surgery, at ambient air contact)
- Pre-operative physiologic measures: Arterial tension (TA)(Just before surgery, at ambient air contact)
- Pre-operative physiologic measures: pH(Just before surgery, at ambient air contact)
- Operative physiologic measures - moment 1: pH(just after induction/intubation, patient laying flat, without pneumoperitoneum)
- Operative physiologic measures - moment 2: FC(just after peritoneal insufflation and anti-trendenlenbourg (anti-trent) implementation)
- Operative physiologic measures - moment 3: CO2(just after pneumoperitoneum exsufflation - patient lying flat)
- Operative physiologic measures - moment 3: PaCO2(just after pneumoperitoneum exsufflation - patient lying flat)
- Operative physiologic measures - if recruitment manoeuvers occurs: PAM(Five minutes after any recruitment manoeuver)
- Operative physiologic measures - moment 2: PaO2(just after peritoneal insufflation and anti-trendenlenbourg (anti-trent) implementation)
- Pre-operative physiologic measures: Oxygen Pulsated Saturation (SpO2)(Just before surgery, at ambient air contact)
- Operative physiologic measures - moment 2: SpO2(just after peritoneal insufflation and anti-trendenlenbourg (anti-trent) implementation)
- Anatomic dead space -if recruitment manoeuvers(Five minutes after any recruitment manoeuver)
- PaO2/FiO2 ratio - moment 2(just after peritoneal insufflation and anti-trendenlenbourg (anti-trent) implementation)
- PaCO2-EtCO2 gradient - preoperative(Just before surgery, at ambient air contact)
- PaCO2-EtCO2 gradient - if recruitment manoeuvers(Five minutes after any recruitment manoeuver)
- Number of postoperative wound infections(30 days after surgery)
- Operative physiologic measures - moment 2: PAM(just after peritoneal insufflation and anti-trendenlenbourg (anti-trent) implementation)
- Operative physiologic measures - moment 2: pH(just after peritoneal insufflation and anti-trendenlenbourg (anti-trent) implementation)
- Operative physiologic measures - if recruitment manoeuvers occurs: FC(Five minutes after any recruitment manoeuver)
- Operative physiologic measures - if recruitment manoeuvers occurs: SpO2(Five minutes after any recruitment manoeuver)
- Operative physiologic measures - if recruitment manoeuvers occurs: PaCO2(Five minutes after any recruitment manoeuver)
- Pre-operative physiologic measures: partial pressure of oxygen in the arterial blood (PaO2)(Just before surgery, at ambient air contact)
- Operative physiologic measures - moment 1: SpO2(just after induction/intubation, patient laying flat, without pneumoperitoneum)
- PaO2/FiO2 ratio - moment 1(just after the anesthesia induction/intubation, patient laying flat, without pneumoperitory)
- PaO2/FiO2 ratio - moment 3(just after pneumoperitoneum exsufflation - patient lying flat)
- PaO2/FiO2 ratio - if recruitment manoeuvers(Five minutes after any recruitment manoeuver)
- Pre-operative physiologic measures: cardiac frequency (FC)(Just before surgery, at ambient air contact)
- Operative physiologic measures - moment 1: CO2(just after induction/intubation, patient laying flat, without pneumoperitoneum)
- Operative physiologic measures - moment 3: PAM(just after pneumoperitoneum exsufflation - patient lying flat)
- Operative physiologic measures - if recruitment manoeuvers occurs: pH(Five minutes after any recruitment manoeuver)
- Operative physiologic measures - if recruitment manoeuvers occurs: PaO2(Five minutes after any recruitment manoeuver)
- Operative physiologic measures - moment 3: PaO2(just after pneumoperitoneum exsufflation - patient lying flat)
- Operative physiologic measures - moment 1: PAM (Average arterial pressure)(just after induction/intubation, patient laying flat, without pneumoperitoneum)
- Operative physiologic measures - moment 2: PaCO2(just after peritoneal insufflation and anti-trendenlenbourg (anti-trent) implementation)
- Operative physiologic measures - moment 2: CO2(just after peritoneal insufflation and anti-trendenlenbourg (anti-trent) implementation)
- Operative physiologic measures - moment 3: FC(just after pneumoperitoneum exsufflation - patient lying flat)
- Operative physiologic measures - if recruitment manoeuvers occurs: CO2(Five minutes after any recruitment manoeuver)
- Operative physiologic measures - moment 1: PaO2(just after induction/intubation, patient laying flat, without pneumoperitoneum)
- Operative physiologic measures - moment 3: SpO2(just after pneumoperitoneum exsufflation - patient lying flat)
研究者
Philippe VAN DER LINDEN
Head of clinic
Brugmann University Hospital