Physiological Effects of Lung Recruitment During General Anesthesia and Low-tidal Volume Ventilation (PEEP-RM)

Physiological Effects of Positive End-expiratory Pressure With or Without Recruiting Maneuvers in Patients Receiving Low-tidal Volume Ventilation During General Anesthesia for Open Abdominal Surgery. A Randomized, Cross-over Study

Low-tidal volume ventilation is arising as a tool to optimize the ventilatory management and to improve clinical outcome in patients undergoing general anesthesia for abdominal surgery.

A recent large randomized controlled trial failed to detect a significant difference between two different approaches for ensuring adequate lung recruitment (PEEP=12 cmH2O + scheduled recruiting maneuvers vs. PEEP 2 cmH2O) during protective ventilation. Thus, in patients undergoing open abdominal surgery and receiving low-tidal volumes, the effects of different positive end-expiratory pressure (PEEP) levels and recruiting maneuvers remain to be established.

Design: prospective, cross-over, physiological trial.

PURPOSE To assess the physiological effects of different PEEP levels with or without scheduled recruiting maneuvers in patients undergoing general anesthesia for open abdominal surgery and receiving low-tidal volume ventilation.

Study Overview

• Status: Completed
• Conditions: Anesthesia, General; Surgery
• Intervention / Treatment: Drug: Fluid resuscitation or amine administration; Drug: General anesthetic; Drug: Fluid administration; Procedure: Low-tidal volume ventilation; Procedure: Scheduled recruiting maneuvers

• Study Type: Interventional
• Enrollment (Actual): 30
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Italy
  • Rome, Italy, 00100
    • General surgery OR, A. Gemelli hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• ASA physical status I-II patients
• scheduled for open abdominal surgery (major gastrointestinal surgery: duodeno-cephalo-pancreatectomy, gastrectomy, hemi-colectomy; gynecological surgery; oncologic surgery)
• Expected duration of surgery >= 150 minutes

Exclusion Criteria:

• Pregnancy
• BMI>30 kg/m^2
• hepatic surgery
• Cardiac failure NYHA>2
• History of chronic respiratory failure

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: CROSSOVER
• Masking: SINGLE

Number of Arms

6

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: PEEP2 + RM; General anesthetic, 40 minutes of Low-tidal volume ventilation with PEEP=2 cmH2O and scheduled recruiting maneuvers at the beginning of each PEEP step, continuous fluid administration at a standard dose, fluid resuscitation or amine administration if deemed necessary by the attending physician blinded to the design of the study	Drug: Fluid resuscitation or amine administration; Fluid administration or amine administration if deemed necessary by the attending physician. Haemodynamics will be monitored through noninvasive cardiac output assessment by arterial pulse contour analysis; Drug: General anesthetic; Total intravenous anesthesia with a standard protocol; Drug: Fluid administration; 3-5 ml/kg of balanced crystalloids will be administered throughout the whole surgical procedure; Procedure: Low-tidal volume ventilation; Volume-control ventilation with tidal volume=7 ml/kg of predicted body weight for the entire surgical procedure. Respiratory rate will be set to maintain EtCO2 within a physiological range and kept unchanged for the entire duration of the study; Procedure: Scheduled recruiting maneuvers; Pressure-control ventilation inspiratory pressure=10 cmH2O. Steplike 5-cmH2O-PEEP increase every 30 seconds to achieve a peep of 35 cmH2O, followed by 5-cmH2O-PEEP reduction every 30 seconds to set PEEP
EXPERIMENTAL: PEEP7 + RM; General anesthetic, 40 minutes of Low-tidal volume ventilation with PEEP=7 cmH2O and scheduled recruiting maneuvers at the beginning of the PEEP step, continuous fluid administration at a standard dose, fluid resuscitation or amine administration if deemed necessary by the attending physician blinded to the design of the study	Drug: Fluid resuscitation or amine administration; Fluid administration or amine administration if deemed necessary by the attending physician. Haemodynamics will be monitored through noninvasive cardiac output assessment by arterial pulse contour analysis; Drug: General anesthetic; Total intravenous anesthesia with a standard protocol; Drug: Fluid administration; 3-5 ml/kg of balanced crystalloids will be administered throughout the whole surgical procedure; Procedure: Low-tidal volume ventilation; Volume-control ventilation with tidal volume=7 ml/kg of predicted body weight for the entire surgical procedure. Respiratory rate will be set to maintain EtCO2 within a physiological range and kept unchanged for the entire duration of the study; Procedure: Scheduled recruiting maneuvers; Pressure-control ventilation inspiratory pressure=10 cmH2O. Steplike 5-cmH2O-PEEP increase every 30 seconds to achieve a peep of 35 cmH2O, followed by 5-cmH2O-PEEP reduction every 30 seconds to set PEEP
EXPERIMENTAL: PEEP12 + RM; General anesthetic, 40 minutes of Low-tidal volume ventilation with PEEP=12 cmH2O and scheduled recruiting maneuvers at the beginning of the PEEP step, continuous fluid administration at a standard dose, fluid resuscitation or amine administration if deemed necessary by the attending physician blinded to the design of the study	Drug: Fluid resuscitation or amine administration; Fluid administration or amine administration if deemed necessary by the attending physician. Haemodynamics will be monitored through noninvasive cardiac output assessment by arterial pulse contour analysis; Drug: General anesthetic; Total intravenous anesthesia with a standard protocol; Drug: Fluid administration; 3-5 ml/kg of balanced crystalloids will be administered throughout the whole surgical procedure; Procedure: Low-tidal volume ventilation; Volume-control ventilation with tidal volume=7 ml/kg of predicted body weight for the entire surgical procedure. Respiratory rate will be set to maintain EtCO2 within a physiological range and kept unchanged for the entire duration of the study; Procedure: Scheduled recruiting maneuvers; Pressure-control ventilation inspiratory pressure=10 cmH2O. Steplike 5-cmH2O-PEEP increase every 30 seconds to achieve a peep of 35 cmH2O, followed by 5-cmH2O-PEEP reduction every 30 seconds to set PEEP
EXPERIMENTAL: PEEP2 - RM; General anesthetic, 40 minutes of Low-tidal volume ventilation with PEEP=2 cmH2O, continuous fluid administration at a standard dose, fluid resuscitation or amine administration if deemed necessary by the attending physician blinded to the design of the study	Drug: Fluid resuscitation or amine administration; Fluid administration or amine administration if deemed necessary by the attending physician. Haemodynamics will be monitored through noninvasive cardiac output assessment by arterial pulse contour analysis; Drug: General anesthetic; Total intravenous anesthesia with a standard protocol; Drug: Fluid administration; 3-5 ml/kg of balanced crystalloids will be administered throughout the whole surgical procedure; Procedure: Low-tidal volume ventilation; Volume-control ventilation with tidal volume=7 ml/kg of predicted body weight for the entire surgical procedure. Respiratory rate will be set to maintain EtCO2 within a physiological range and kept unchanged for the entire duration of the study
EXPERIMENTAL: PEEP7 - RM; General anesthetic, 40 minutes of Low-tidal volume ventilation with PEEP=7 cmH2O, continuous fluid administration at a standard dose, fluid resuscitation or amine administration if deemed necessary by the attending physician blinded to the design of the study	Drug: Fluid resuscitation or amine administration; Fluid administration or amine administration if deemed necessary by the attending physician. Haemodynamics will be monitored through noninvasive cardiac output assessment by arterial pulse contour analysis; Drug: General anesthetic; Total intravenous anesthesia with a standard protocol; Drug: Fluid administration; 3-5 ml/kg of balanced crystalloids will be administered throughout the whole surgical procedure; Procedure: Low-tidal volume ventilation; Volume-control ventilation with tidal volume=7 ml/kg of predicted body weight for the entire surgical procedure. Respiratory rate will be set to maintain EtCO2 within a physiological range and kept unchanged for the entire duration of the study
EXPERIMENTAL: PEEP12 - RM.; General anesthetic, 40 minutes of Low-tidal volume ventilation with PEEP=12 cmH2O, continuous fluid administration at a standard dose, fluid resuscitation or amine administration if deemed necessary by the attending physician blinded to the design of the study	Drug: Fluid resuscitation or amine administration; Fluid administration or amine administration if deemed necessary by the attending physician. Haemodynamics will be monitored through noninvasive cardiac output assessment by arterial pulse contour analysis; Drug: General anesthetic; Total intravenous anesthesia with a standard protocol; Drug: Fluid administration; 3-5 ml/kg of balanced crystalloids will be administered throughout the whole surgical procedure; Procedure: Low-tidal volume ventilation; Volume-control ventilation with tidal volume=7 ml/kg of predicted body weight for the entire surgical procedure. Respiratory rate will be set to maintain EtCO2 within a physiological range and kept unchanged for the entire duration of the study

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Driving Pressure	Respiratory system elastic pressure (Plateau pressure-total PEEP)	At the end of each 40-minute step

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Lung strain	Lung static and dynamic strain	At the end of each 40-minute step
Dead space	Approximated as the difference between End-tidal CO2 and PaCO2 divided by PaCO2	At the end of each 40-minute step
Oxygenation	PaO2/FiO2	At the end of each 40-minute step
Lung recruitment	% (lung recruitment/change in end-expiratory lung volume)	At the end of each 40-minute step
Lung overdistension due to PEEP	% (lung overdistension/change in end-expiratory lung volume)	At the end of each 40-minute step
Functional residual capacity	Change in functional residual capacity due to PEEP, measured with the Nitrogen washin-washout technique	At the end of each 40-minute step
Heart rate	heart rate	At the end of each 40-minute step
Blood pressure	Arterial blood pressure	At the end of each 40-minute step
Stroke volume	Stroke volume, measured by pulse contour analysis	At the end of each 40-minute step
Stroke volume variation	Stroke volume variation, measured by pulse contour analysis	At the end of each 40-minute step
Cardiac Output	Stroke volume x heart rate	At the end of each 40-minute step
Fluid requirements	Fluid bolus requirements, according to the decision of the attending physician blinded to the design of the study	At the end of each 40-minute step
Vasoactive agents	Vasoactive agents requirements, according to the decision of the attending physician blinded to the design of the study	At the end of each 40-minute step
Adverse events	Adverse events	At the end of each 40-minute step

Collaborators and Investigators

• Sponsor: Catholic University of the Sacred Heart

Study record dates

Study Major Dates

• Study Start (ACTUAL): March 20, 2017
• Primary Completion (ACTUAL): November 30, 2020
• Study Completion (ACTUAL): November 30, 2020

Study Registration Dates

• First Submitted: March 14, 2017
• First Submitted That Met QC Criteria: March 14, 2017
• First Posted (ACTUAL): March 20, 2017

Study Record Updates

• Last Update Posted (ACTUAL): January 29, 2021
• Last Update Submitted That Met QC Criteria: January 28, 2021
• Last Verified: January 1, 2021

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Central Nervous System Depressants; Anesthetics; Anesthetics, General
• Other Study ID Numbers: 10989/15

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

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