Protective Mechanical Ventilation and Risk of Postoperative Complications in Abdominal Surgery

Randomized controlled trial, comparing two groups of 40 patients each scheduled for open major abdominal surgery. The intervention group was ventilated with a protective strategy consisting on a low Tidal volume (Vt) (6ml/kg of predicted body weight (PBW)), positive end expiratory pressure (PEEP) = 10 cm H2O and recruitment manoeuvres (RM) after disconnection from the ventilator, the control group had classic ventilation (Vt = 8 ml/kg of PBW, PEEP = 4 cmH2O and no RM).

Study Overview

• Status: Completed
• Conditions: Postoperative Complications; Ventilator-Induced Lung Injury; Mechanical Ventilation Complication
• Intervention / Treatment: Procedure: protective ventilation

Detailed Description

This randomized controlled trial, was approved by the institutional ethics committee of our hospital. Informed consent was obtained from all the participants before randomization. Investigators included 80 patients (40 in each group), ASA I or II, planned for open abdominal surgery lasting more than 2 hours under general anesthesia.

Patients were not included if they had specially acute respiratory disease, severe asthma or emphysema, sleep apnea syndrome, septic shock and body mass index (BMI) < 16 or > 35 Kg/m2. Participants were excluded in case of serious peroperative anesthetic complications or hemorrhagic shock.

Primary endpoint was postoperative pulmonary complications occurring within the first 7 days after surgery (defined as hypoxemia, Broncho-pneumopathy, pulmonary infiltrate, acute respiratory distress syndrome, atelectasis, pleural effusion).

Secondary endpoints for all participants were intra-operative complications (change in SpO2 when dropped less than 90%, hypotension <90 mmHg lasting more than 3 min, need for vasopressor administration, new arrhythmia), postoperative extrapulmonary complications (septic shock, postoperative surgical complications, heart disease complications). Investigators recorded for all participants length of hospital stay and mortality rate were .

Investigators randomly allocated patients before entering to the operating room to:

• Control Group (CG): patients ventilated with Vt of 8 ml/kg of predicted body weight (PBW), a low level of PEEP (4 cm H2O) without RM.
• Protective Ventilation Group (PVG): patients ventilated with a low Vt of 6 ml/Kg of PBW, a high level of PEEP (10 cm H2O), RMs applied after intubation, before extubation and in case of disconnection from the ventilator.

Other ventilation settings, type of anesthesia, fluid administration and post operative pain management were standardized.

In the postoperative period, investigators daily assessed clinical examination and arterial blood gas if pulse oximetry dropped. For all participants, a chest X ray, blood count creatinine and C reactive protein were done at day 1 and day 3.

Data were presented as means and standard deviation [SD] or frequencies. Statistical analyses were performed using SPSS statistical software version 20.0. A p-value of 0.05 was considered significant.

• Study Type: Interventional
• Enrollment (Actual): 80
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• ASA I or II, planned for open abdominal surgery lasting more than 2 hours under general anesthesia

Exclusion Criteria:

• Patients were not included if they had specially acute respiratory disease, severe asthma or emphysema, sleep apnea syndrome, septic shock and BMI < 16 or > 35 Kg/m2. They were excluded in case of serious peroperative anesthetic complications or hemorrhagic shock.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: PREVENTION
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: NONE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
NO_INTERVENTION: control group; Vt = 8 ml/kg of PBW and PEEP = 4 cm H2O
EXPERIMENTAL: protective ventilation group; Vt = 6ml/kg of PBW, PEEP = 10 and RM if disconnected	Procedure: protective ventilation; the aim of the intervention is to ovoid Ventilator induced lung injury and inflammatory stress

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative pulmonary complications	Postoperative pulmonary complications occurring within the first 7 days after surgery (defined as hypoxemia, Broncho pneumopathy, pulmonary infiltrate, acute respiratory distress syndrome, atelectasis, pleural effusion)	Postoperative pulmonary complications within the first 7 days after surgery

Collaborators and Investigators

• Sponsor: Mongi Slim Hospital

Study record dates

Study Major Dates

• Study Start (ACTUAL): July 1, 2015
• Primary Completion (ACTUAL): December 31, 2016
• Study Completion (ACTUAL): December 31, 2016

Study Registration Dates

• First Submitted: May 19, 2017
• First Submitted That Met QC Criteria: May 23, 2017
• First Posted (ACTUAL): May 24, 2017

Study Record Updates

• Last Update Posted (ACTUAL): May 24, 2017
• Last Update Submitted That Met QC Criteria: May 23, 2017
• Last Verified: May 1, 2017

More Information

Terms related to this study

• Keywords: protective mechanical ventilation
• Additional Relevant MeSH Terms: Pathologic Processes; Respiratory Tract Diseases; Lung Diseases; Wounds and Injuries; Thoracic Injuries; Postoperative Complications; Lung Injury; Ventilator-Induced Lung Injury
• Other Study ID Numbers: Mongi Slim OR

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No