Intraoperative Protective Mechanical Ventilation in Patients Requiring Emergency Abdominal Surgery

Not Applicable

Completed

• Conditions: Postoperative Morbidity; Mechanical Ventilation; Emergency Abdominal Surgery; General Anesthesia
• Interventions: Other: Driving-pressure-guided group; Other: Low PEEP

• Registration Number: NCT03987789
• Lead Sponsor: University Hospital, Clermont-Ferrand

Brief Summary

The aim of this study is to compare the effects of a strategy aimed at increasing alveolar recruitment (high PEEP levels adjusted according to driving pressure and recruitment maneuvers) with that of a strategy aimed at minimizing alveolar distension (low PEEP level without recruitment maneuver) on postoperative respiratory failure and mortality in patients receiving low VT ventilation during emergency abdominal surgery.

Detailed Description

Emergency abdominal surgery is associated with a high risk of morbidity and mortality. Postoperative pulmonary complications (PPCs) are the second most common surgical complication and adversely influence surgical morbidity. Postoperative respiratory failure (PRF) is one of the most serious pulmonary complication.

Two hypotheses can be forward by the literature. First, a low VT lung protective ventilation in combination with a strategy aimed at minimizing alveolar distension by using low PEEP level (and without recruitment maneuver) could improve postoperative outcome while reducing the risk of hemodynamic alterations or, second, could increase the risk of PRF compared with a strategy aimed at increasing alveolar recruitment using higher PEEP level adjusted according to driving pressure in combination with recruitment maneuvers in adult patients undergoing emergency abdominal surgery. Given the uncertainties, and in order to determine the impact of lung protective ventilation strategies on clinical outcomes of high-risk surgical patients, a randomized trial is needed.

Our primary hypothesis is that, during low VT ventilation, a strategy aimed at increasing alveolar recruitment by using high PEEP levels adjusted according to driving pressure in combination with recruitment maneuvers could be more effective at reducing PRF and mortality after emergency abdominal surgery than a strategy aimed at minimizing alveolar distension by using lower PEEP without recruitment maneuver.

Given the number of patients for whom the question applies, the prevalence and the burden of PPCs, the study can have significant clinical importance and public health implications.

Study Timeline

• Study First Submitted: 2019-06-12
• Study First Submitted QC: 2019-06-14
• Study First Posted: 2019-06-17
• Study Start: 2021-02-18
• Status Verified: 2022-07
• Primary Completion: 2022-07-29
• Study Completion: 2022-10-27
• Last Update Submitted: 2022-10-28
• Last Update Posted: 2022-10-31

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 707

Inclusion Criteria

• Adult (≥18 years)
• Patients requiring emergency (defined by the need to proceed to surgery within a few hours after diagnosis)
• Laparoscopic or non-laparoscopic abdominal surgery under general anesthesia and with an expected duration of at least two hours

Exclusion Criteria

• Patients already receiving mechanical ventilation for more than 12 hours before enrollment
• Intracranial hypertension
• Chronic respiratory disease requiring oxygen therapy or mechanical ventilation at home
• Undrained pneumothorax or subcutaneous emphysema
• Patients for which death is deemed imminent and inevitable or patients with an underlying disease process with a life expectancy of less than 3 month
• Body mass index (BMI) >40 kg/m2
• Pregnant or breastfeeding women
• Patients already enrolled in the IMPROVE-2 trial
• Participation in a confounding trial with mortality or PRF as the main endpoint
• Patient's or relative's refusal to participate
• Guardianship or trusteeship patient
• No affiliation to the Social Security system

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Driving-pressure-guided group	Driving-pressure-guided group	Patients will receive PEEP levels individually set at the highest possible value (up to 15 cmH2O) providing a driving pressure (airway plateau pressure minus PEEP) lower than 13 cmH2O, in addition to recruitment maneuvers
Low PEEP group	Low PEEP	Patients will receive a PEEP level ≤5 cmH2O without recruitment maneuvers

Primary Outcome Measures

Name	Time	Method
Postoperative respiratory failure	Hospital discharge - Up to day 30	Composite criteria : 1. - Failure to wean from the ventilator after surgery (Yes or No); 2. - Requiring unplanned reintubation (Yes or No); 3. - Curative non-invasive ventilation once extubated postoperatively (Yes or No); 4. - Death (all cause of mortality) (Yes or No); If at least one of these 4 criteria is answered yes, the composite criterion (i.e. the primary outcome) will be answered yes

Secondary Outcome Measures

Name	Time	Method
Median ephedrine doses during surgery	Day 1	µg/kg/min
SOFA	Day 7	Sequential-related Organ Failure Assessment
Ventilator-free days	Day 30	The number of days alive and with unassisted breathing
Time to successful tracheal extubation	48 hours	Absence of ventilatory support during the first 48 hours after extubation
Median norepinephrine doses during surgery	Day 1	µg/kg/min
Duration of ICU stay	Up to day 90	Duration of ICU stay
Postoperative pulmonary complications	Day 30	Hypoxemia, pneumonia? development of acute respiratory distress syndrome (ARDS)
Postoperative extra-pulmonary complications	Day 30	sepsis and septic shock, renal dysfunction
Intensive care unit (ICU)-free days	Day 30	Intensive care unit (ICU)-free days
Duration of hospital stay	Up to day 90	Duration of hospital stay
All-cause mortality	Day 90	All-cause mortality
Hemodynamic instability	Up to day 30	Hemodynamic instability ventilatory-related defined as a drop of arterial systolic pressure below 80 mmHg for more than 5 minutes not responding to treatment
Duration of invasive mechanical ventilation	Up to Day 30	Duration of invasive mechanical ventilation from randomization to first tracheal extubation
Total duration of mechanical ventilation	Up to Day 30	Total duration of mechanical ventilation (additive, for all épisodes)
Total volume of intraoperative fluids	Day 1	Total volume of intraoperative fluids (crystalloids and colloids)
Median phenylephrine doses during surgery	Day 1	µg/kg/min
Time to death	Up to 90 days	Time to death (Days)
Pneumothorax	Up to day 30	Pneumothorax ventilatory-related

Trial Locations

Locations (6)

Institut Paoli Calmette; 🇫🇷 Marseille, France

Assistance Publique-Hôpitaux de Paris; 🇫🇷 Paris, France

University hospital; 🇫🇷 Toulouse, France

Hospital; 🇫🇷 Valenciennes, France

Assistance Publique-Hôpitaux de Marseille; 🇫🇷 Marseille, France

University Hospital; 🇫🇷 Nantes, France