Different Tidal Volume on Oxygenation, Respiratory Mechanics, and Pulmonary Complications in Older Patients Undergoing Trendelenburg Pneumoperitoneum Surgery

Study Overview
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Brief Summary
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The investigators want to assess the effect of intraoperative low tidal volume vs intermediate tidal volume on respiratory mechanics, oxygenation and pulmonary complications in older patients undergoing Trendelenburg pneumoperitoneum surgery.

Official Title
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Effect of Intraoperative Low Tidal Volume vs Intermediate Tidal Volume on Oxygenation, Respiratory Mechanics, and Pulmonary Complications in Older Patients Undergoing Trendelenburg Pneumoperitoneum Surgery: A Randomized Clinical Trial

Conditions
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Trendelenburg, Neumoperitoneum, Oxygenation, Respiratory, Pulmonary

Intervention / Treatment
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* Other: group L (Vt 6 ml/kg)
* Other: group I (Vt 8 ml/kg)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiologists (ASA) physical status I-III class; Colorectal cancer patients; Elective laparoscopic colorectal surgery; expected duration of surgery greater than 2 hours. Exclusion Criteria: serious complications associated with other systems; severe cardiac insufficiency; renal failure; body mass index (BMI) greater than 30 kg/m2 or less than 18 kg/m2; the use of low tidal volume and consequent hypercapnia can induce harm; refusal to participate in the study.

Ages Eligible for Study
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Minimum Age: 66 Years

Sexes Eligible for Study
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All

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
Interventional Model Description: A randomized, double-blind, controlled trial
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: group L<br>Ventilation was subsequently changed to individualized positive end-expiratory pressure and recruitment maneuvers during trendelenburg pneumoperitoneum, and the tidal volume was set to 6 ml/kg. | Other: group L (Vt 6 ml/kg)<br>* low tidal volume ventilation (tidal volume was set to 6 ml/kg)<br>|
| Experimental: group I<br>Ventilation was subsequently changed to individualized positive end-expiratory pressure and recruitment maneuvers during trendelenburg pneumoperitoneum, and the tidal volume was set to 8 ml/kg. | Other: group I (Vt 8 ml/kg)<br>* intermediate tidal volume ventilation (tidal volume was set to 8 ml/kg)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PaO2/FiO2 | the outcome in mmHg | the lowest value at one hour after extubation, day-1 to day-3 | 
| hypoxemia | the outcome in fraction | From date of patient admission until the date of discharge, assessed up to 7 days | 
| pneumonia | the outcome in fraction | From date of patient admission until the date of discharge, assessed up to 7 days | 
| bronchospasm | the outcome in fraction | From date of patient admission until the date of discharge, assessed up to 7 days | 
| atelectasis | the outcome in fraction | From date of patient admission until the date of discharge, assessed up to 7 days | 
| pulmonary congestion | the outcome in fraction | From date of patient admission until the date of discharge, assessed up to 7 days | 
| respiratory failure | the outcome in fraction | From date of patient admission until the date of discharge, assessed up to 7 days | 
| pleural effusion | the outcome in fraction | From date of patient admission until the date of discharge, assessed up to 7 days | 
| pneumothorax | the outcome in fraction | From date of patient admission until the date of discharge, assessed up to 7 days | 
| unplanned requirement for postoperative invasive or noninvasive ventilation | the outcome in fraction | From date of patient admission until the date of discharge, assessed up to 7 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Tidal volume | the outcome in milliliter | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3) | 
| respiratory rate | the outcome in times/minute (frequency) | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3) | 
| dead space fraction | the outcome in fraction | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3) | 
| A-aDO2 | the outcome in mmHg | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3) | 
| intrapulmonary shunt | the outcome in fraction | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3) | 
| peak airway pressure | the outcome in cmH2O | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3) | 
| plateau airway pressure | the outcome in cmH2O | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3) | 
| mean airway pressure | the outcome in cmH2O | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3) | 
| dynamic compliance | the outcome in milliliter/cmH2O | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3) | 
| arterial blood pH | the outcome in number | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| arterial blood PO2 | the outcome in mmHg | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| arterial blood PCO2 | the outcome in mmHg | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| arterial blood Hb | the outcome in g/dl | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| arterial blood Hct | the outcome in fraction | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| arterial blood SO2 | the outcome in fraction | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| arterial blood K | the outcome in mmol/L | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| arterial blood Na | the outcome in mmol/L | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| arterial blood Ca | the outcome in mmol/L | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| arterial blood Cl | the outcome in mmol/L | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| arterial blood Glu | the outcome in mmol/L | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| arterial blood Lac | the outcome in mmol/L | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| arterial blood tBil | the outcome in umol/L | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| arterial blood SBE | the outcome in mmol/L | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| arterial blood ABE | the outcome in mmol/L | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| PaO2/FiO2 | the outcome in mmHg | before anesthesia induction (T1); 60 minutes after initiation of the Trendelenburg position and CO2 pneumoperitoneum (T2), and 10 minutes after desufflation and resuming the supine position (T3). | 
| unplanned intensive care unit admission | the outcome in fraction | From date of finishing surgery until the date of patient discharge, assessed up to 7 days | 
| intensive care unit length of stay | the outcome in days | From date of finishing surgery until the date of patient discharge, assessed up to 7 days | 
| postoperative mortality | the outcome in fraction | From date of finishing surgery until the date of patient discharge, assessed up to 7 days | 
| hospital length of stay | the outcome in days | From date of patient admission until the date of discharge, assessed up to 10 days |