Single-step vs Stepwise Lung Recruitment Maneuvers After Cardiopulmonary Bypass

Comparison of Hemodynamic and Pulmonary Outcomes Between Single-Step and Stepwise Lung Recruitment Maneuvers After Cardiopulmonary Bypass: A Randomized Controlled Trial

This prospective randomized controlled trial aims to compare the hemodynamic and pulmonary effects of single-step and stepwise lung recruitment maneuvers in adult patients undergoing elective cardiac surgery with cardiopulmonary bypass. After separation from cardiopulmonary bypass, patients will be randomized to receive either a single-step sustained inflation recruitment maneuver or a stepwise incremental recruitment maneuver, both combined with 8 cmH₂O positive end-expiratory pressure. The primary outcome is the change in cardiac index before and after the recruitment maneuver. Secondary outcomes include lung ultrasound atelectasis score, and hemodynamic parameters.

Study Overview

• Status: Recruiting
• Conditions: Atelectasis, Postoperative
• Intervention / Treatment: Procedure: Single Step Lung Recruitment Maneuver; Procedure: Stepwise Lung Recruitment Maneuver

Detailed Description

Atelectasis frequently develops after cardiopulmonary bypass due to lung ischemia-reperfusion injury, inflammatory response, and mechanical factors related to cardiac surgery. Lung recruitment maneuvers are commonly used to improve lung aeration and oxygenation; however, increased intrathoracic pressure during recruitment may negatively affect venous return and cardiac output.

In this randomized controlled trial, adult patients undergoing elective open-heart surgery with cardiopulmonary bypass will be allocated to receive either a single-step sustained inflation recruitment maneuver or a stepwise incremental recruitment maneuver, both combined with 8 cmH₂O positive end-expiratory pressure after separation from cardiopulmonary bypass. Hemodynamic variables, particularly cardiac index, will be assessed before and after recruitment. Pulmonary effects will be evaluated using lung ultrasound atelectasis scoring and arterial blood gas analysis. The study aims to identify the recruitment strategy that provides optimal pulmonary benefits while preserving hemodynamic stability in this high-risk patient population.

• Study Type: Interventional
• Enrollment (Estimated): 52
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Burhan Dost, MD; Phone Number: +903623121919; Email: burhandost@hotmail.com

Study Locations

• Turkey (Türkiye)
  • Atakum
    • Samsun, Atakum, Turkey (Türkiye), 55270
      • Recruiting
      • Ondokuz Mayıs University, Faculty of Medicine
      • Contact: Burhan Dost, MD; Phone Number: +903623121919; Email: burhandost@hotmail.com
      • Contact: Hilal H Kandemir, MD; Phone Number: +903623121919; Email: hhilal.kandemir@gmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age 18-80 years
• ASA (American Society of Anesthesiologists) II-IV
• Patients undergoing elective cardiac surgery (coronary artery bypass grafting, mitral valve replacement, aortic valve replacement)

Exclusion Criteria:

• Emergency surgery
• Presence of perioperative arrhythmia
• <35% left ventricular ejection fraction
• >50 mmHg systolic pulmonary artery pressure
• Known chronic obstructive pulmonary disease or interstitial lung disease
• Pneumothorax
• Mean arterial pressure <60 mmHg during recruitment maneuver
• New York Heart Association (NYHA) class III-IV heart failure
• Advanced cardiomyopathy or severe mitral regurgitation
• Cross-clamp time longer than 2 hours
• Requirement for high-dose inotropic or vasopressor support
• Patients who cannot be extubated after postoperative 24 hours

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Grup Single Step; A single step lung recruitment maneuver for 30 seconds will be applied	Procedure: Single Step Lung Recruitment Maneuver; A sustained inflation lung recruitment maneuver with an airway pressure of 30 cmH₂O applied for 30 seconds after separation from cardiopulmonary bypass, combined with 8 cmH₂O positive end-expiratory pressure.
Active Comparator: Grup Stepwise; A stepwise recruitment maneuver will be applied.	Procedure: Stepwise Lung Recruitment Maneuver; A stepwise lung recruitment maneuver in which airway pressure is increased by 5 cmH₂O every 5 seconds up to 30 cmH₂O and then decreased in the same manner after separation from cardiopulmonary bypass, combined with 8 cmH₂O positive end-expiratory pressure.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Cardiac Index	Difference in cardiac index measured before and after the lung recruitment maneuver.	Intraoperative period

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The heart rate measurement	Heart rate will be recorded preoperatively; after induction; immediately before the recruitment maneuver (RM); during RM at the point of maximum airway pressure; at the end of RM; 30 minutes after RM; at postoperative hour 1; and immediately after extubation.	Intraoperative period and postoperative day 1.
The mean arterial pressure measurement	Mean arterial pressure will be recorded preoperatively; after induction; immediately before the recruitment maneuver (RM); during RM at the point of maximum airway pressure; at the end of RM; 30 minutes after RM; at postoperative hour 1; and immediately after extubation.	Intraoperative period and postoperative day 1.
Systemic vascular resistance index measurement	Systemic vascular resistance index will be recorded preoperatively; after induction; immediately before the recruitment maneuver (RM); during RM at the point of maximum airway pressure; at the end of RM; 30 minutes after RM; at postoperative hour 1; and immediately after extubation.	Intraoperative period and postoperative day 1.
Stroke volume variation	Dynamic hemodynamic parameters, including stroke volume variation (SVV, %), will be recorded as separate variables using invasive arterial waveform analysis. Measurements will be obtained after induction; immediately before the recruitment maneuver (RM); during RM at the point of maximum airway pressure; at the end of RM; 30 minutes after RM; at postoperative hour 1; and immediately after extubation.	Intraoperative period and postoperative day 1.
Arterial elastance	Dynamic hemodynamic parameters including arterial elastance (Ea, mmHg/mL), will be recorded as separate variables using invasive arterial waveform analysis. Measurements will be obtained after induction; immediately before the recruitment maneuver (RM); during RM at the point of maximum airway pressure; at the end of RM; 30 minutes after RM; at postoperative hour 1; and immediately after extubation.	Intraoperative period and postoperative day 1.
Contractility	Dynamic hemodynamic parameters, including cardiac contractility indices, will be recorded as separate variables using invasive arterial waveform analysis. Measurements will be obtained after induction; immediately before the recruitment maneuver (RM); during RM at the point of maximum airway pressure; at the end of RM; 30 minutes after RM; at postoperative hour 1; and immediately after extubation.	Intraoperative period and postoperative day 1.
Lung ultrasound atelectasis score	Change in lung ultrasound atelectasis score before and after the recruitment maneuver. Lung aeration was assessed using a 12-region quantitative lung ultrasound (LUS) score (0-36) based on the ESICM-ESPNIC consensus. Each region was graded 0-3 (0 = normal aeration; 1 = mild loss with B-lines/subpleural changes ≤50%; 2 = moderate loss with coalescent B-lines or small consolidation <2-2.5 cm; 3 = severe loss with large consolidation ≥2-2.5 cm). Higher scores indicated greater aeration loss.	Intraoperative period and postoperative day 1
Peak airway pressure	Peak airway pressure (Ppeak), measured in cmH₂O, will be recorded after induction; immediately before the recruitment maneuver (RM); during RM at the point of maximum airway pressure; at the end of RM; 30 minutes after RM; at postoperative hour 1; and immediately after extubation.	Intraoperative period and postoperative day 1.
Plateau pressure	plateau pressure (Pplat), measured in cmH₂O, will be recorded after induction; immediately before the recruitment maneuver (RM); during RM at the point of maximum airway pressure; at the end of RM; 30 minutes after RM; at postoperative hour 1; and immediately after extubation.	Intraoperative period and postoperative day 1.
Dynamic lung compliance	Dynamic lung compliance (Cdyn), expressed as mL/cmH₂O, will be recorded after induction; immediately before the recruitment maneuver (RM); during RM at the point of maximum airway pressure; at the end of RM; 30 minutes after RM; at postoperative hour 1; and immediately after extubation.	Intraoperative period and postoperative day 1.
Driving pressure	Driving pressure, calculated as plateau pressure minus positive end-expiratory pressure (Pplat - PEEP) and expressed in cmH₂O, will be recorded after induction; immediately before the recruitment maneuver (RM); during RM at the point of maximum airway pressure; at the end of RM; 30 minutes after RM; at postoperative hour 1; and immediately after extubation.	Intraoperative period and postoperative day 1.
Positive end-expiratory pressure	Positive end-expiratory pressure (PEEP), measured in cmH₂O, will be recorded after induction; immediately before the recruitment maneuver (RM); during RM at the point of maximum airway pressure; at the end of RM; 30 minutes after RM; at postoperative hour 1; and immediately after extubation.	Intraoperative period and postoperative day 1.
Arterial pH	Arterial pH (unitless) measured by arterial blood gas analysis will be recorded after induction; immediately before the recruitment maneuver (RM); during RM at the point of maximum airway pressure; at the end of RM; 30 minutes after RM; at postoperative hour 1; and immediately after extubation.	Intraoperative period and postoperative day 1.
Partial pressure of arterial oxygen	Partial pressure of arterial oxygen (PaO₂, mmHg) measured by arterial blood gas analysis will be recorded after induction; immediately before the recruitment maneuver (RM); during RM at the point of maximum airway pressure; at the end of RM; 30 minutes after RM; at postoperative hour 1; and immediately after extubation.	Intraoperative period and postoperative day 1.
Partial pressure of arterial carbon dioxide	Partial pressure of arterial carbon dioxide (PaCO₂, mmHg) measured by arterial blood gas analysis will be recorded after induction; immediately before the recruitment maneuver (RM); during RM at the point of maximum airway pressure; at the end of RM; 30 minutes after RM; at postoperative hour 1; and immediately after extubation.	Intraoperative period and postoperative day 1.
Serum lactate level	Change in serum lactate level measured perioperatively.	Intraoperative period and postoperative day 1
Extubation time	After the operation, the time until the patient is extubated will be recorded.	Postoperative day 1
Length of intensive care unit stay (ICU)	Time from ICU admission to ICU discharge.	The time from admission to the ICU to the time of discharge to the hospital ward; during the hospital stay, an average of 7 days

Collaborators and Investigators

• Sponsor: Ondokuz Mayıs University

Publications and helpful links

General Publications

• Nielsen J, Ostergaard M, Kjaergaard J, Tingleff J, Berthelsen PG, Nygard E, Larsson A. Lung recruitment maneuver depresses central hemodynamics in patients following cardiac surgery. Intensive Care Med. 2005 Sep;31(9):1189-94. doi: 10.1007/s00134-005-2732-z. Epub 2005 Aug 12.
• Celebi S, Koner O, Menda F, Korkut K, Suzer K, Cakar N. The pulmonary and hemodynamic effects of two different recruitment maneuvers after cardiac surgery. Anesth Analg. 2007 Feb;104(2):384-90. doi: 10.1213/01.ane.0000252967.33414.44.
• Longo S, Siri J, Acosta C, Palencia A, Echegaray A, Chiotti I, Parisi A, Ricci L, Natal M, Suarez-Sipmann F, Tusman G. Lung recruitment improves right ventricular performance after cardiopulmonary bypass: A randomised controlled trial. Eur J Anaesthesiol. 2017 Feb;34(2):66-74. doi: 10.1097/EJA.0000000000000559.
• Myatra SN. Hemodynamic effects of alveolar recruitment maneuvres in the operating room: Proceed with caution. J Anaesthesiol Clin Pharmacol. 2019 Oct-Dec;35(4):431-433. doi: 10.4103/joacp.JOACP_223_19. No abstract available.
• Mongodi S, Cortegiani A, Alonso-Ojembarrena A, Biasucci DG, Bos LDJ, Bouhemad B, Cantinotti M, Ciuca I, Corradi F, Girard M, Gregorio-Hernandez R, Gualano MR, Mojoli F, Ntoumenopoulos G, Pisani L, Raimondi F, Rodriguez-Fanjul J, Savoia M, Smit MR, Tuinman PR, Zieleskiewicz L, De Luca D. ESICM-ESPNIC international expert consensus on quantitative lung ultrasound in intensive care. Intensive Care Med. 2025 Jun;51(6):1022-1049. doi: 10.1007/s00134-025-07932-y. Epub 2025 May 12.

Study record dates

Study Major Dates

• Study Start (Actual): February 15, 2026
• Primary Completion (Estimated): February 1, 2027
• Study Completion (Estimated): May 1, 2027

Study Registration Dates

• First Submitted: January 26, 2026
• First Submitted That Met QC Criteria: February 19, 2026
• First Posted (Actual): February 25, 2026

Study Record Updates

• Last Update Posted (Actual): April 6, 2026
• Last Update Submitted That Met QC Criteria: April 2, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: atelectasis; cardiac surgery; hemodynamics; cardiopulmonary bypass; lung ultrasound; positive end-expiratory pressure; cardiac index; lung recruitment maneuver
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Lung Diseases; Pulmonary Atelectasis
• Other Study ID Numbers: LRMCPB000

Drug and device information, study documents

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