Intraoperative PEEP Setting During Laparoscopic Gynecologic Surgery

Study Overview
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Brief Summary
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The creation of pneumoperitoneum during laparoscopic surgery can have significant effects on the respiratory system including decreased respiratory system compliance, decreased vital capacity and functional residual capacity and atelectasis formation. Intraoperative mechanical ventilation, especially setting of positive end-expiratory pressure (PEEP) has an important role in respiratory management during laparoscopic surgery. The aim of this study is to determine whether setting of PEEP guided by measurement of pleural pressure would improve oxygenation and respiratory system compliance during laparoscopic surgery.

Detailed Description
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As minimally invasive procedure with numerous advantages compared with open surgery, laparoscopic surgery has been substantially performed worldwide. The creation of pneumoperitoneum during laparoscopic surgery, however, can have significant effects on the respiratory system including decreased respiratory system compliance, decreased vital capacity and functional residual capacity and atelectasis formation. These pathophysiologic changes may put patients at risk of postoperative pulmonary complications. Therefore, intraoperative mechanical ventilation, especially setting of positive end-expiratory pressure (PEEP) has an important role in respiratory management during laparoscopic surgery. Nevertheless, there is no consensus on the optimal PEEP level and the best method to set PEEP during laparoscopic surgery. In patients with acute respiratory distress syndrome, PEEP set according to pleural pressure measured by using esophageal balloon catheter significantly has beneficial effects in terms of oxygenation, compliance and possible mortality. The aim of this study is to determine whether setting of PEEP guided by measurement of pleural pressure would improve oxygenation and respiratory system compliance during laparoscopic surgery.

Official Title
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Intraoperative Positive End-Expiratory Pressure Setting Guided By Esophageal Pressure Measurement in Patients Undergoing Laparoscopic Gynecologic Surgery

Conditions
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Positive-Pressure Respiration/Methods, Esophagus/Physiopathology, Pleura/Physiopathology, Gynecologic Surgical Procedures, Laparoscopy, Humans, Female

Intervention / Treatment
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* Procedure: PEEP setting based on esophageal pressure measured


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with age of equal or more than 18 years old undergoing laparoscopic gynecologic surgery with anticipated surgical duration of more than 2 hours Exclusion Criteria: Patients with ASA physical status of equal or more than 3 Patients with significant cardiovascular or respiratory diseases Patients with significant pathological lesion in pharynx and esophagus that preclude placement of esophageal balloon catheter Patients with contraindications for PEEP titration such as increased intracranial pressure or unstable hemodynamic Patients with arrhythmias Patients who refuse to provide written informed consent Patients undergoing surgery with duration of less than 2 hours

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Group E<br>PEEP set according to esophageal pressure measured | Procedure: PEEP setting based on esophageal pressure measured<br>* PEEP is set on the basis of esophageal pressure measurement with the aim to maintain transpulmonary pressure during expiration between 0 and 5 cmH2O<br>|
| No Intervention: Group C<br>PEEP set at 5 cm H2O | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in PaO2 between Group E and Group C |  | At 15 minutes after initiation of pneumoperitoneum | 
| Difference in PaO2 between Group E and Group C |  | At 60 minutes after initiation of pneumoperitoneum | 
| Difference in PaO2 between Group E and Group C |  | At 30 minutes after arrival in recovery room | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in compliance of respiratory system between Group E and Group C |  | At 15 minutes and 60 minutes after initiation of pneumoperitoneum, and 30 minutes after arrival in recovery room | 
| Difference in alveolar dead space to tidal volume ratio between Group E and Group C |  | At 15 minutes and 60 minutes after initiation of pneumoperitoneum, and 30 minutes after arrival in recovery room | 
| Difference in hemodynamics between Group E and Group C |  | At 15 minutes and 60 minutes after initiation of pneumoperitoneum | 
| Proportion of thoracoabdominal transmission of intraabdominal pressure |  | At 15 minutes and 60 minutes after initiation of pneumoperitoneum | 
| Adverse respiratory events | Adverse respiratory events define as requirement of oxygen supplement after discharge from the recovery room, episodes of desaturation (SpO2 of less than 90%), now-onset respiratory infection, new infiltration on chest radiograph, or respiratory failure. | During 72 hours postoperatively or until discharge from hospital | 
| Length of hospital stay |  | Up to 30 days after the operation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Intraoperative mechanical ventilation, Positive-end expiratory pressure, Esophageal pressure, Transpulmonary pressure, Laparoscopic gynecologic surgery