Intraoperative Lung Protective Ventilation Needs Periodic Lung Recruitment Maneuvers

Study Overview
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Brief Summary
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Postoperative Pulmonary Complications (PPC) are common. It severely affects postoperative recovery, particularly in abdominal surgery. Several studies showed that intraoperative lung-protective ventilation with periodic lung recruitment maneuvers could reduce postoperative pulmonary complications. Other studies showed that intraoperative lung protective ventilation without periodic lung recruitment maneuvers could also reduce postoperative pulmonary complications. The purpose of this study was to compare the effects of the above two regimens on postoperative pulmonary complications.

Official Title
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Intraoperative Lung Protective Ventilation With or Without Periodic Lung Recruitment Maneuvers on Pulmonary Complications After Major Abdominal Surgery: a Prospective Randomized Controlled Study

Conditions
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Postoperative Complications, Abdominal Surgery, Intraoperative Mechanical Ventilation

Intervention / Treatment
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* Other: periodic lung recruitment maneuvers


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Undergoing elective major abdominal surgery (expected duration of mechanical ventilation ≥2 h) had an intermediate to high risk of developing postoperative pulmonary complications as indicated by an Assess Respiratory Risk in Surgical Patients in Catalonia score (≥26) Pulse oxygen saturation in room air ≥ 94% Exclusion Criteria: younger than 18 years had received invasive mechanical ventilation for longer than 1 h within the last 2 weeks prior to surgery had a history of pneumonia within 1 month prior to surgery had severe chronic obstructive pulmonary disease or pulmonary bullae had a progressive neuromuscular illness severe heart dysfunction (New York Heart Association classification ≥4) with an American Society of Anesthesiologists (ASA) physical status of IV or higher Intracranial hypertension were pregnant (excluded by laboratory analysis) were involved in other interventional studies

Ages Eligible for Study
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Minimum Age: 18 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intensive intraoperative lung-protective ventilation<br>intraoperative lung-protective ventilation with periodic lung recruitment maneuvers | Other: periodic lung recruitment maneuvers<br>* lung recruitment maneuvers repeated every 30 minutes<br>|
| No Intervention: Moderate intraoperative lung-protective ventilation<br>intraoperative lung-protective ventilation without periodic lung recruitment maneuvers | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of respiratory failure | Respiratory failure: postoperative arterial partial pressure of oxygen (PaO2) < 8 kPa (60 mmHg) on room air, a PaO2: Inhaled oxygen concentration (FI02) ratio < 40 kPa (300 mmHg) or arterial oxyhaemoglobin saturation measured with pulse oximetry < 90% and requiring oxygen therapy | Day 0 to 7 after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Rate of mild respiratory failure | Mild respiratory failure: PaO2 < 60 mmHg or pulse oxygen saturation (SpO2) < 90% on room air, but SpO2 can be raised to more than 90% when inhaling oxygen through nasal catheter less than 3 L/min. | Day 0 to 7 after surgery | 
| Rate of moderate respiratory failure | Moderate respiratory failure: PaO2 < 60 mmHg or SpO2 < 90% when inhaling oxygen through nasal catheter less than 3 L/min, but SpO2 can be raised to more than 90% when inhaling oxygen more than 3 L/min. | Day 0 to 7 after surgery | 
| Rate of severe respiratory failure | Severe respiratory failure: experienced an invasive or noninvasive ventilator therapy, or PaO2 < 60 mmHg or SpO2 < 90% when administering oxygen via a nasal catheter at 3 L/min or more. | Day 0 to 7 after surgery | 
| Rate of sustained hypoxaemia | Sustained hypoxaemia: during a follow-up visit when the patient was awake and breathing room air, SpO2 ≤ 92% or the change of SpO2 (ΔSpO2, preoperative SpO2 minus postoperative SpO2) ≥ 5% on any three consecutive days. | Day 0 to 7 after surgery | 
| Rate of modified respiratory failure | Modified respiratory failure: met the criterion of moderate or severe respiratory failure, or mild respiratory failure in twice follow-up, or mild respiratory failure with sustained hypoxemia. | Day 0 to 7 after surgery | 
| Rate of respiratory infections | Respiratory infections: receiving antibiotics for a suspected respiratory infection and met at least one of the following criteria: new or changed sputum, new or changed lung opacities, fever, leukocyte count >12 × 109 /L | Day 0 to 7 after surgery | 
| Rate of pneumonia | Pneumonia: United States Centers for Disease Control definition of pneumonia | Day 0 to 7 after surgery | 
| Rate of aspiration pneumonitis | Aspiration pneumonitis: acute lung injury after the inhalation of regurgitated gastric contents. | Day 0 to 7 after surgery | 
| Rate of pneumothorax | Pneumothorax: air in the pleural space with no vascular bed surrounding the visceral pleura | Intraoperative or day 0 to 7 after surgery | 
| Rate of pleural effusion | Pleural effusion: chest radiograph demonstrating blunting of the costophrenic angle, loss of sharp silhouette of the ipsilateral hemidiaphragm in upright position, evidence of displacement of adjacent anatomical structures or (in supine position) a hazy opacity in one hemithorax with preserved vascular shadows | Day 0 to 7 after surgery | 
| Rate of Acute Respiratory Distress Syndrome | Acute Respiratory Distress Syndrome: The Berlin definition of Respiratory Distress Syndrome | Day 0 to 7 after surgery | 
| Rate of Quick Sequential Organ Failure Assessment (qSOFA) ≥ 2 | qSOFA ≥ 2: Two or more of: Respiratory rate ≥22/min, Altered mentation, Systolic blood pressure ≤ 100 mm Hg | Day 0 to 7 after surgery | 
| Rate of Systemic Inflammatory Response Syndrome (SIRS) | SIRS: Two or more of: Temperature >38°C or <36°C, Heart rate > 90/min, Respiratory rate >20/min or PaCO2<32 mmHg (4.3kPa), White blood cell count >12 000/mm3 or 10% immature bands | Day 0 to 7 after surgery | 
| Rate of Major Adverse Cardiac and Cerebrovascular Events (MACCE) | MACCE: Stroke, coma, non-fatal cardiac arrest, acute myocardial infarction, congestive heart failure. | Day 0 to 7 after surgery | 
| Postoperative hospitalization days | The duration between the operation date and the actual discharge date, days | Day 0 to 30 after surgery | 
| Rate of Unexpected admission to intensive care unit (ICU) | Unexpected admission to ICU: It does not include patients who enter ICU at the request of surgeons but have normal spontaneous breathing, stable circulation and no disturbance of consciousness. | Day 0 to 30 after surgery | 
| Rate of death | Death from any cause | Day 0 to 30 after surgery | 
| Rate of intraoperative hypotension | Intraoperative hypotension: mean arterial pressure (MAP) < 60 mmHg lasting more than 3 minutes | Intraoperative, period of mechanical ventilation | 
| Rate of intraoperative needing for vasoconstrictor | Intraoperative vasoconstrictor needs: MAP < 60 mmHg and using any catecholamines | Intraoperative, period of mechanical ventilation | 
| Rate of intraoperative hypoxemia | Intraoperative hypoxemia: SpO2 ≤ 92% lasting more than 3 minutes | Intraoperative, period of mechanical ventilation | 
| Rate of Intraoperative bradycardia | Intraoperative bradycardia: heart rate ≤ 50 bpm and the decrease of heart rate from the basic value ≥ 20% lasting more than 3 minutes | Intraoperative, period of mechanical ventilation | 
| Rate of post-anesthesia care unit respiratory failure | Post-anesthesia care unit respiratory failure: PaO2 < 8 kPa (60 mmHg) on room air, a PaO2:FI02 ratio < 40 kPa (300 mmHg) or arterial oxyhaemoglobin saturation measured with pulse oximetry < 90% and requiring oxygen therapy | Postoperative, during postanesthesia care unit | 
| Intraoperative mechanical power | Mechanical power, J/min | Intraoperative: after half an hour of mechanical ventilation, before the end of mechanical ventilation | 
| PaO2 / FI02 | PaO2 / FI02, mmHg | Intraoperative: after half an hour of mechanical ventilation, before the end of mechanical ventilation | 
| Postoperative pulmonary complications score | Postoperative pulmonary complications score: graded on a scale from 0 (no pulmonary complications) to 4 (the most severe complications). | Day 0 to 7 after surgery |