AtelectasisNCT07325812
Effects of Periodic Recruitment Maneuvers on Atelectasis and Respiratory Mechanics During Elective Spine Surgery Assessed by Lung Ultrasonography
A study testing Alveolar Recruitment Maneuver in people with Atelectasis and Mechanical Ventilation, run by Prof. Dr. Cemil Tascıoglu Education and Research Hospital Organization at 1 site in Turkey (Türkiye).
Trial summary
During general anesthesia, particularly in patients undergoing spine surgery in the prone (face-down) position, increased intrathoracic and abdominal pressure may reduce lung compliance and promote the development of atelectasis (partial lung collapse). Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Atelectasis, Mechanical Ventilation, General Anesthesia
- What is being tested?
- Alveolar Recruitment Maneuver
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 60 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 11 Apr 2026to 28 Aug 2026
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Adults aged 18 to 65 years
- Scheduled for elective lumbar spine surgery under general anesthesia
- Surgery planned to be performed in the prone position
- Expected surgical duration of at least 2 hours
- American Society of Anesthesiologists (ASA) physical status I-II
- Ability to provide written informed consent
Who cannot join
- Body mass index (BMI) greater than 30 kg/m²
- History of thoracic surgery
- Known or suspected chronic pulmonary disease (e.g., chronic obstructive pulmonary disease, restrictive lung disease)
- Clinically significant cardiac disease
- Pregnancy or breastfeeding
- Known airway anomalies
- Intraoperative surgical duration shorter than 2 hours
- Refusal or inability to provide informed consent
Trial locations and contacts
1 site in 1 country.
Turkey (Türkiye)1 site
Prof. Dr. Cemil Tascıoglu Education and Research Hospital Organization
Istanbul
About this study
Official title: Evaluation of the Effects of Periodic Recruitment Maneuvers on Atelectasis and Respiratory Mechanics in Elective Spine Surgery Using Lung Ultrasonography
During general anesthesia, particularly in patients undergoing spine surgery in the prone (face-down) position, increased intrathoracic and abdominal pressure may reduce lung compliance and promote the development of atelectasis (partial lung collapse). Atelectasis can impair intraoperative oxygenation and may increase the risk of postoperative pulmonary complications. Alveolar recruitment maneuvers (ARM) are routinely used in anesthesia practice to reopen collapsed lung regions; however, it remains unclear whether periodic application of ARM throughout surgery provides additional benefit compared with standard single-time application.
This prospective, randomized controlled clinical study aims to evaluate whether periodic alveolar recruitment maneuvers applied during elective spine surgery in the prone position reduce intraoperative atelectasis and improve respiratory mechanics compared with the standard approach of performing ARM only after positioning and before extubation. Adult patients undergoing elective spine surgery under general anesthesia will be randomly assigned to either a periodic ARM group or a standard ARM group.
Read more
Lung aeration will be assessed using lung ultrasound, a non-invasive and radiation-free bedside imaging method. The primary outcome is the incidence of intraoperative atelectasis assessed before extubation. Secondary outcomes include lung ultrasound aeration scores, respiratory mechanics parameters (such as airway pressures and compliance), oxygenation indices, and the occurrence of transient intraoperative respiratory or hemodynamic events.
The findings of this study may help optimize intraoperative ventilation strategies in prone spine surgery and contribute to improved perioperative respiratory safety.
Read the detailed description
Atelectasis frequently develops during general anesthesia due to reduced functional residual capacity, diaphragmatic displacement, and alterations in ventilation-perfusion relationships. These effects may be more pronounced during spine surgery performed in the prone position, where increased intra-abdominal and intrathoracic pressures and altered chest wall mechanics can further impair lung compliance and promote regional lung collapse. Intraoperative atelectasis has been associated with impaired oxygenation and may contribute to postoperative pulmonary complications, making its prevention an important objective in anesthetic management.
Alveolar recruitment maneuvers (ARM) are commonly used in anesthesia practice to reopen collapsed alveoli and improve lung aeration. Standard practice often involves performing a recruitment maneuver after positioning and occasionally before extubation; however, maintenance of lung aeration throughout prolonged prone procedures may be challenging. Some previous studies, including studies in pediatric populations, suggest that repeated recruitment maneuvers during surgery may provide more sustained lung aeration compared with a single application. Nevertheless, data in adult patients undergoing prone spine surgery remain limited.
This investigator-initiated, single-center randomized controlled clinical trial has been designed to evaluate the impact of periodic intraoperative alveolar recruitment maneuvers applied at predefined intraoperative intervals according to the study protocol on lung aeration and respiratory mechanics in adult patients undergoing elective spine surgery in the prone position under general anesthesia. The study primarily aims to assess lung aeration using lung ultrasound, while secondary outcomes include respiratory mechanics and perioperative physiological parameters. The periodic recruitment strategy will be compared with a standard recruitment approach used in routine anesthesia care. All ventilation maneuvers will be performed within established safety limits commonly accepted in clinical practice and will be immediately discontinued if clinically indicated. No experimental drugs, devices, or additional invasive procedures are introduced as part of the study.
Lung aeration will be evaluated using transthoracic lung ultrasound, a bedside, radiation-free, non-invasive imaging modality increasingly adopted for perioperative pulmonary assessment. Lung ultrasound allows semi-quantitative evaluation of regional aeration loss and detection of atelectasis using validated scoring systems, providing dynamic information without exposing patients to ionizing radiation. Ultrasound assessments will be performed by a trained investigator blinded to group allocation in order to minimize assessment bias.
In addition to ultrasound-based aeration assessment, intraoperative respiratory parameters such as airway pressures, lung compliance, oxygenation indices, and relevant perioperative physiological variables will be recorded to characterize the respiratory effects of different recruitment strategies. Safety monitoring will include documentation of transient hemodynamic or respiratory changes potentially associated with recruitment maneuvers.
By evaluating a practical ventilation strategy that relies on routinely used anesthetic techniques and a non-invasive monitoring tool, this study aims to provide clinically applicable data on intraoperative respiratory management in prone spine surgery. The findings may contribute to improved understanding of whether periodic recruitment maneuvers support maintenance of lung aeration and respiratory physiology compared with standard approaches.
- Being tested
- Alveolar Recruitment Maneuver
- Keywords
- Atelectasis, Alveolar Recruitment Maneuver, Lung Ultrasound, Prone Position, Respiratory Mechanics
- Medical subject headings
- Pulmonary Atelectasis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Alveolar Recruitment ManeuverProcedure or surgery
Also called Lung Recruitment Maneuver
Alveolar recruitment maneuvers will be performed under general anesthesia using standard mechanical ventilation techniques within routine clinical safety limits. After prone positioning, a baseline recruitment maneuver will be applied by stepwise increasing positive end-expiratory pressure (PEEP) from 8 cmH₂O to 10 cmH₂O and 15 cmH₂O while maintaining an upper airway pressure limit of ≤30 cmH₂O for approximately 10 seconds. Following the maneuver, mechanical ventilation will continue with a PEEP level of approximately 8 cmH₂O according to routine clinical practice.
In the periodic recruitment group, additional recruitment maneuvers will be repeated approximately once per hour during the intraoperative period. In the standard recruitment group, no additional intraoperative maneuvers will be applied apart from a final recruitment maneuver performed before extubation as part of routine anesthetic care.
| Study group | Role | What they receive |
|---|---|---|
| Periodic Alveolar Recruitment Maneuver Group | Experimental | Participants assigned to this arm will receive standardized general anesthesia and mechanical ventilation according to routine clinical practice. After prone positioning, all participants will undergo a baseline alveolar recruitment maneuver performed within established clinical safety limits.
In this experimental arm, additional alveolar recruitment maneuvers will be applied approximately once per hour throughout the intraoperative period to help maintain lung aeration. A final recruitment maneuver will also be performed before extubation as part of standard anesthetic care. Apart from the timing of recruitment maneuvers, intraoperative anesthetic and ventilatory management will be conducted according to routine clinical practice and individualized based on patient requirements. Receives: Procedure: Alveolar Recruitment Maneuver |
| Standard Alveolar Recruitment Maneuver Group | Active comparator | Participants assigned to this arm will receive standardized general anesthesia and mechanical ventilation according to routine clinical practice. After prone positioning, a baseline alveolar recruitment maneuver will be performed within established clinical safety limits.
No additional recruitment maneuvers will be applied during the intraoperative period apart from a final recruitment maneuver performed before extubation as part of standard anesthetic care. Intraoperative anesthetic and ventilatory management will otherwise follow routine clinical practice and will be guided by patient safety considerations. Receives: Procedure: Alveolar Recruitment Maneuver |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence of Significant Intraoperative Atelectasis Assessed by Lung Ultrasound
Significant intraoperative atelectasis will be defined as the presence of significant loss of lung aeration identified by transthoracic lung ultrasound, corresponding to a regional score of 2 or higher in at least one predefined lung region using a standardized 12-region semi-quantitative lung ultrasound aeration scoring system. In this system, each region is scored from 0 to 3, with higher scores indicating greater loss of lung aeration. Lung ultrasound examinations will be performed according to a predefined scanning protocol, and image interpretation will be conducted by an assessor blinded to group allocation.
Measured: Immediately prior to tracheal extubation under general anesthesia at the completion of surgery.
Secondary outcomes (8)
Peak Inspiratory Pressure
Peak inspiratory pressure will be recorded from the anesthesia ventilator during mechanical ventilation and documented prospectively to characterize intraoperative respiratory mechanics.
Measured: Assessed 15 minutes after prone positioning, at approximately hourly intraoperative intervals, and immediately prior to tracheal extubation.
Dynamic Lung Compliance
Dynamic lung compliance will be calculated from ventilator-derived tidal volume and airway pressure measurements during mechanical ventilation and documented prospectively to characterize respiratory system mechanics under general anesthesia.
Measured: Assessed 15 minutes after prone positioning, at approximately hourly intraoperative intervals, and immediately prior to tracheal extubation.
Peripheral Oxygen Saturation
Peripheral oxygen saturation (SpO2) will be recorded using standard pulse oximetry at predefined intraoperative study time points for analysis. Peripheral oxygen saturation (SpO₂) will be continuously monitored using standard pulse oximetry during general anesthesia and early postoperative recovery. Recorded values will be documented at predefined time points for analysis.
Measured: Assessed 15 minutes after prone positioning, at approximately hourly intraoperative intervals, and immediately prior to tracheal extubation.
Incidence of Oxygen Desaturation
Oxygen desaturation will be defined as any documented episode of peripheral oxygen saturation (SpO2) below 95 percent measured by pulse oximetry during intraoperative monitoring or within 30 minutes after arrival in the post-anesthesia care unit (PACU).
Measured: From induction of anesthesia until 30 minutes after arrival in the post-anesthesia care unit (PACU).
Total Lung Ultrasound Aeration Score
Total lung aeration will be assessed using transthoracic lung ultrasound with a standardized 12-region semi-quantitative lung ultrasound aeration scoring system. Each region will be scored from 0 to 3 (0 = normal aeration, 1 = moderate loss of aeration, 2 = severe loss of aeration, 3 = lung consolidation), resulting in a total score ranging from 0 to 36, where higher scores indicate greater loss of lung aeration. The total lung ultrasound score represents a semi-quantitative measure of global loss of lung aeration.
Examinations will be performed by an investigator blinded to group allocation.
Measured: Assessed 15 minutes after prone positioning, immediately prior to tracheal extubation, and within 30 minutes after arrival in the post-anesthesia care unit (PACU).
Plateau Airway Pressure
Plateau airway pressure will be recorded from the anesthesia ventilator during mechanical ventilation and documented prospectively to characterize intraoperative respiratory mechanics.
Measured: Assessed 15 minutes after prone positioning, at approximately hourly intraoperative intervals, and immediately prior to tracheal extubation.
Alveolar-Arterial Oxygen Gradient
The alveolar-arterial oxygen gradient will be calculated using arterial blood gas measurements together with the corresponding inspired oxygen fraction (FiO2) values obtained at predefined study time points to evaluate gas exchange. Measurements will be recorded in parallel with lung ultrasound assessments and at approximately hourly intraoperative intervals.
Measured: Assessed 15 minutes after prone positioning, at approximately hourly intraoperative intervals, immediately prior to tracheal extubation, and within 30 minutes after arrival in the post-anesthesia care unit (PACU).
Driving Pressure
Driving pressure will be calculated from ventilator-derived airway pressure measurements as the difference between plateau pressure and positive end-expiratory pressure during mechanical ventilation and documented prospectively to characterize respiratory mechanics.
Measured: Assessed 15 minutes after prone positioning, at approximately hourly intraoperative intervals, and immediately prior to tracheal extubation.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Jan 2026
- Study start11 Apr 2026
- Primary completion28 Aug 2026
- Study completion28 Aug 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (7)Papers the sponsor has linked to this study.
- Other trials for AtelectasisStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Participants will be randomized in a 1:1 ratio using a computer-generated block randomization scheme to one of two parallel groups. Following standardized general anesthesia induction and prone positioning, all participants will receive a baseline alveolar recruitment maneuver performed within routine clinical safety limits. In the intervention group, additional alveolar recruitment maneuvers will be applied approximately once per hour throughout the intraoperative period, whereas participants in the control group will receive no additional recruitment maneuvers beyond the baseline intervention until the standard pre-extubation maneuver performed in both groups. Participants will remain in their assigned group throughout the study without crossover. Lung ultrasound assessments will be performed by an investigator blinded to group allocation.
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 60 participants (actual)
Sponsor and investigators
- Lead sponsor
- Prof. Dr. Cemil Tascıoglu Education and Research Hospital Organization
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, SERAP KARACALAR, Prof. Dr. Cemil Tascıoglu Education and Research Hospital Organization
- Investigators
- Serap KARACALAR, MD (Doctor of Medicine), Principal investigator, Prof. Dr. Cemil Tascıoglu Education and Research Hospital Organization
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07325812
- Sponsor's protocol ID
- CTERHO-SOZER-LUS-ARM-PRONE-001
- Status last verified
- Oct 2026
- First submitted
- 25 Dec 2025
- Last updated
- 29 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Publications
York J, Nugent K. Using lung ultrasound to guide PEEP determination in mechanically ventilated patients. Southwest Respir Crit Care Chron. 2023;11(47):10-20.
Lee JM, Lee SK, Kim KM, Kim YJ, Park EY. Comparison of volume-controlled ventilation mode and pressure-controlled ventilation with volume-guaranteed mode in the prone position during lumbar spine surgery. BMC Anesthesiol. 2019 Jul 27;19(1):133. doi: 10.1186/s12871-019-0806-7.
PubMed 31351445Gunenc FS, Seyidova I, Ozbilgin S, Ur K, Hanci V. Comparison of pressure controlled, volume controlled, and volume guaranteed pressure controlled modes in prone position in patients operated for lumbar disc herniation: A randomized trial. Medicine (Baltimore). 2024 Feb 9;103(6):e37227. doi: 10.1097/MD.0000000000037227.
PubMed 38335373Jang YE, Ji SH, Kim EH, Lee JH, Kim JT, Kim HS. Effect of regular alveolar recruitment on intraoperative atelectasis in paediatric patients ventilated in the prone position: a randomised controlled trial. Br J Anaesth. 2020 May;124(5):648-655. doi: 10.1016/j.bja.2020.01.022. Epub 2020 Mar 10.
PubMed 32169254Acosta CM, Maidana GA, Jacovitti D, Belaunzaran A, Cereceda S, Rae E, Molina A, Gonorazky S, Bohm SH, Tusman G. Accuracy of transthoracic lung ultrasound for diagnosing anesthesia-induced atelectasis in children. Anesthesiology. 2014 Jun;120(6):1370-9. doi: 10.1097/ALN.0000000000000231.
PubMed 24662376Guldner A, Kiss T, Serpa Neto A, Hemmes SN, Canet J, Spieth PM, Rocco PR, Schultz MJ, Pelosi P, Gama de Abreu M. Intraoperative protective mechanical ventilation for prevention of postoperative pulmonary complications: a comprehensive review of the role of tidal volume, positive end-expiratory pressure, and lung recruitment maneuvers. Anesthesiology. 2015 Sep;123(3):692-713. doi: 10.1097/ALN.0000000000000754.
PubMed 26120769Hartland BL, Newell TJ, Damico N. Alveolar recruitment maneuvers under general anesthesia: a systematic review of the literature. Respir Care. 2015 Apr;60(4):609-20. doi: 10.4187/respcare.03488. Epub 2014 Nov 25.
PubMed 25425708
Study at a glance
From the registry record, last updated by the sponsor on 29 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluation of the Effects of Periodic Recruitment Maneuvers on Atelectasis and Respiratory Mechanics in Elective Spine Surgery Using Lung Ultrasonography
- ClinicalTrials.gov ID
- NCT07325812
- Acronym / sponsor ID
- CTERHO-SOZER-LUS-ARM-PRONE-001
- Keywords
- Atelectasis, Alveolar Recruitment Maneuver, Lung Ultrasound, Prone Position, Respiratory Mechanics
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 60 participants (actual)
- Lead sponsor
- Prof. Dr. Cemil Tascıoglu Education and Research Hospital OrganizationUniversity, hospital or other
- Study start
- 11 Apr 2026 (actual)
- Primary completion
- 28 Aug 2026 (actual)
- Study completion
- 28 Aug 2026 (actual)
- First posted
- 8 Jan 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
During general anesthesia, particularly in patients undergoing spine surgery in the prone (face-down) position, increased intrathoracic and abdominal pressure may reduce lung compliance and promote the development of atelectasis (partial lung collapse). Atelectasis can impair intraoperative oxygenation and may increase the risk of postoperative pulmonary complications. Alveolar recruitment maneuvers (ARM) are routinely used in anesthesia practice to reopen collapsed lung regions; however, it remains unclear whether periodic application of ARM throughout surgery provides additional benefit compared with standard single-time application.
This prospective, randomized controlled clinical study aims to evaluate whether periodic alveolar recruitment maneuvers applied during elective spine surgery in the prone position reduce intraoperative atelectasis and improve respiratory mechanics compared with the standard approach of performing ARM only after positioning and before extubation. Adult patients undergoing elective spine surgery under general anesthesia will be randomly assigned to either a periodic ARM group or a standard ARM group.
Lung aeration will be assessed using lung ultrasound, a non-invasive and radiation-free bedside imaging method. The primary outcome is the incidence of intraoperative atelectasis assessed before extubation. Secondary outcomes include lung ultrasound aeration scores, respiratory mechanics parameters (such as airway pressures and compliance), oxygenation indices, and the occurrence of transient intraoperative respiratory or hemodynamic events.
The findings of this study may help optimize intraoperative ventilation strategies in prone spine surgery and contribute to improved perioperative respiratory safety.
Detailed description
Atelectasis frequently develops during general anesthesia due to reduced functional residual capacity, diaphragmatic displacement, and alterations in ventilation-perfusion relationships. These effects may be more pronounced during spine surgery performed in the prone position, where increased intra-abdominal and intrathoracic pressures and altered chest wall mechanics can further impair lung compliance and promote regional lung collapse. Intraoperative atelectasis has been associated with impaired oxygenation and may contribute to postoperative pulmonary complications, making its prevention an important objective in anesthetic management.
Alveolar recruitment maneuvers (ARM) are commonly used in anesthesia practice to reopen collapsed alveoli and improve lung aeration. Standard practice often involves performing a recruitment maneuver after positioning and occasionally before extubation; however, maintenance of lung aeration throughout prolonged prone procedures may be challenging. Some previous studies, including studies in pediatric populations, suggest that repeated recruitment maneuvers during surgery may provide more sustained lung aeration compared with a single application. Nevertheless, data in adult patients undergoing prone spine surgery remain limited.
This investigator-initiated, single-center randomized controlled clinical trial has been designed to evaluate the impact of periodic intraoperative alveolar recruitment maneuvers applied at predefined intraoperative intervals according to the study protocol on lung aeration and respiratory mechanics in adult patients undergoing elective spine surgery in the prone position under general anesthesia. The study primarily aims to assess lung aeration using lung ultrasound, while secondary outcomes include respiratory mechanics and perioperative physiological parameters. The periodic recruitment strategy will be compared with a standard recruitment approach used in routine anesthesia care. All ventilation maneuvers will be performed within established safety limits commonly accepted in clinical practice and will be immediately discontinued if clinically indicated. No experimental drugs, devices, or additional invasive procedures are introduced as part of the study.
Lung aeration will be evaluated using transthoracic lung ultrasound, a bedside, radiation-free, non-invasive imaging modality increasingly adopted for perioperative pulmonary assessment. Lung ultrasound allows semi-quantitative evaluation of regional aeration loss and detection of atelectasis using validated scoring systems, providing dynamic information without exposing patients to ionizing radiation. Ultrasound assessments will be performed by a trained investigator blinded to group allocation in order to minimize assessment bias.
In addition to ultrasound-based aeration assessment, intraoperative respiratory parameters such as airway pressures, lung compliance, oxygenation indices, and relevant perioperative physiological variables will be recorded to characterize the respiratory effects of different recruitment strategies. Safety monitoring will include documentation of transient hemodynamic or respiratory changes potentially associated with recruitment maneuvers.
By evaluating a practical ventilation strategy that relies on routinely used anesthetic techniques and a non-invasive monitoring tool, this study aims to provide clinically applicable data on intraoperative respiratory management in prone spine surgery. The findings may contribute to improved understanding of whether periodic recruitment maneuvers support maintenance of lung aeration and respiratory physiology compared with standard approaches.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
- Model description
- Participants will be randomized in a 1:1 ratio using a computer-generated block randomization scheme to one of two parallel groups. Following standardized general anesthesia induction and prone positioning, all participants will receive a baseline alveolar recruitment maneuver performed within routine clinical safety limits. In the intervention group, additional alveolar recruitment maneuvers will be applied approximately once per hour throughout the intraoperative period, whereas participants in the control group will receive no additional recruitment maneuvers beyond the baseline intervention until the standard pre-extubation maneuver performed in both groups. Participants will remain in their assigned group throughout the study without crossover. Lung ultrasound assessments will be performed by an investigator blinded to group allocation.
| Arm | Type | Receives |
|---|---|---|
| Periodic Alveolar Recruitment Maneuver Group | Experimental | Procedure: Alveolar Recruitment ManeuverParticipants assigned to this arm will receive standardized general anesthesia and mechanical ventilation according to routine clinical practice. After prone positioning, all participants will undergo a baseline alveolar recruitment maneuver performed within established clinical safety limits. In this experimental arm, additional alveolar recruitment maneuvers will be applied approximately once per hour throughout the intraoperative period to help maintain lung aeration. A final recruitment maneuver will also be performed before extubation as part of standard anesthetic care. Apart from the timing of recruitment maneuvers, intraoperative anesthetic and ventilatory management will be conducted according to routine clinical practice and individualized based on patient requirements. |
| Standard Alveolar Recruitment Maneuver Group | Active comparator | Procedure: Alveolar Recruitment ManeuverParticipants assigned to this arm will receive standardized general anesthesia and mechanical ventilation according to routine clinical practice. After prone positioning, a baseline alveolar recruitment maneuver will be performed within established clinical safety limits. No additional recruitment maneuvers will be applied during the intraoperative period apart from a final recruitment maneuver performed before extubation as part of standard anesthetic care. Intraoperative anesthetic and ventilatory management will otherwise follow routine clinical practice and will be guided by patient safety considerations. |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Adults aged 18 to 65 years
- Scheduled for elective lumbar spine surgery under general anesthesia
- Surgery planned to be performed in the prone position
- Expected surgical duration of at least 2 hours
- American Society of Anesthesiologists (ASA) physical status I-II
Key exclusion criteria (8 listed)
- Body mass index (BMI) greater than 30 kg/m²
- History of thoracic surgery
- Known or suspected chronic pulmonary disease (e.g., chronic obstructive pulmonary disease, restrictive lung disease)
- Clinically significant cardiac disease
- Pregnancy or breastfeeding
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Alveolar Recruitment ManeuverAlso: Lung Recruitment ManeuverAlveolar recruitment maneuvers will be performed under general anesthesia using standard mechanical ventilation techniques within routine clinical safety limits. After prone positioning, a baseline recruitment maneuver will be applied by stepwise increasing positive end-expiratory pressure (PEEP) from 8 cmH₂O to 10 cmH₂O and 15 cmH₂O while maintaining an upper airway pressure limit of ≤30 cmH₂O for approximately 10 seconds. Following the maneuver, mechanical ventilation will continue with a PEEP level of approximately 8 cmH₂O according to routine clinical practice. In the periodic recruitment group, additional recruitment maneuvers will be repeated approximately once per hour during the intraoperative period. In the standard recruitment group, no additional intraoperative maneuvers will be applied apart from a final recruitment maneuver performed before extubation as part of routine anesthetic care. | Procedure or surgery | Periodic Alveolar Recruitment Maneuver Group, Standard Alveolar Recruitment Maneuver Group |
Primary outcome
Incidence of Significant Intraoperative Atelectasis Assessed by Lung Ultrasound
Time frame: Immediately prior to tracheal extubation under general anesthesia at the completion of surgery.
Significant intraoperative atelectasis will be defined as the presence of significant loss of lung aeration identified by transthoracic lung ultrasound, corresponding to a regional score of 2 or higher in at least one predefined lung region using a standardized 12-region semi-quantitative lung ultrasound aeration scoring system. In this system, each region is scored from 0 to 3, with higher scores indicating greater loss of lung aeration. Lung ultrasound examinations will be performed according to a predefined scanning protocol, and image interpretation will be conducted by an assessor blinded to group allocation.
8 secondary outcomes
Peak Inspiratory Pressure
Time frame: Assessed 15 minutes after prone positioning, at approximately hourly intraoperative intervals, and immediately prior to tracheal extubation.
Dynamic Lung Compliance
Time frame: Assessed 15 minutes after prone positioning, at approximately hourly intraoperative intervals, and immediately prior to tracheal extubation.
Peripheral Oxygen Saturation
Time frame: Assessed 15 minutes after prone positioning, at approximately hourly intraoperative intervals, and immediately prior to tracheal extubation.
Incidence of Oxygen Desaturation
Time frame: From induction of anesthesia until 30 minutes after arrival in the post-anesthesia care unit (PACU).
Total Lung Ultrasound Aeration Score
Time frame: Assessed 15 minutes after prone positioning, immediately prior to tracheal extubation, and within 30 minutes after arrival in the post-anesthesia care unit (PACU).
Plateau Airway Pressure
Time frame: Assessed 15 minutes after prone positioning, at approximately hourly intraoperative intervals, and immediately prior to tracheal extubation.
Alveolar-Arterial Oxygen Gradient
Time frame: Assessed 15 minutes after prone positioning, at approximately hourly intraoperative intervals, immediately prior to tracheal extubation, and within 30 minutes after arrival in the post-anesthesia care unit (PACU).
Driving Pressure
Time frame: Assessed 15 minutes after prone positioning, at approximately hourly intraoperative intervals, and immediately prior to tracheal extubation.
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Oct 2026.
- BackgroundYork J, Nugent K. Using lung ultrasound to guide PEEP determination in mechanically ventilated patients. Southwest Respir Crit Care Chron. 2023;11(47):10-20.
- Background: PubMed 31351445Lee JM, Lee SK, Kim KM, Kim YJ, Park EY. Comparison of volume-controlled ventilation mode and pressure-controlled ventilation with volume-guaranteed mode in the prone position during lumbar spine surgery. BMC Anesthesiol. 2019 Jul 27;19(1):133. doi: 10.1186/s12871-019-0806-7.
- Background: PubMed 38335373Gunenc FS, Seyidova I, Ozbilgin S, Ur K, Hanci V. Comparison of pressure controlled, volume controlled, and volume guaranteed pressure controlled modes in prone position in patients operated for lumbar disc herniation: A randomized trial. Medicine (Baltimore). 2024 Feb 9;103(6):e37227. doi: 10.1097/MD.0000000000037227.
- Background: PubMed 32169254Jang YE, Ji SH, Kim EH, Lee JH, Kim JT, Kim HS. Effect of regular alveolar recruitment on intraoperative atelectasis in paediatric patients ventilated in the prone position: a randomised controlled trial. Br J Anaesth. 2020 May;124(5):648-655. doi: 10.1016/j.bja.2020.01.022. Epub 2020 Mar 10.
- Background: PubMed 24662376Acosta CM, Maidana GA, Jacovitti D, Belaunzaran A, Cereceda S, Rae E, Molina A, Gonorazky S, Bohm SH, Tusman G. Accuracy of transthoracic lung ultrasound for diagnosing anesthesia-induced atelectasis in children. Anesthesiology. 2014 Jun;120(6):1370-9. doi: 10.1097/ALN.0000000000000231.
- Background: PubMed 26120769Guldner A, Kiss T, Serpa Neto A, Hemmes SN, Canet J, Spieth PM, Rocco PR, Schultz MJ, Pelosi P, Gama de Abreu M. Intraoperative protective mechanical ventilation for prevention of postoperative pulmonary complications: a comprehensive review of the role of tidal volume, positive end-expiratory pressure, and lung recruitment maneuvers. Anesthesiology. 2015 Sep;123(3):692-713. doi: 10.1097/ALN.0000000000000754.
- Background: PubMed 25425708Hartland BL, Newell TJ, Damico N. Alveolar recruitment maneuvers under general anesthesia: a systematic review of the literature. Respir Care. 2015 Apr;60(4):609-20. doi: 10.4187/respcare.03488. Epub 2014 Nov 25.
Related trials for Atelectasis
Recruiting
Comparing Surfactant Administration Through Supraglottic Airway and Thin Catheter for Preterm Infants
Surfactant, Respiratory Distress Syndrome (Neonatal)
Active, not recruiting
Stepwise PEEP vs Sustained Inflation in Bariatric Surgery Patients
Recruitment, Bariatric Surgery Candidate
Not yet recruiting
Bedside Assessment of Right Ventricular Output Lying in Prone Or Supine
Right Ventricular Function, Prone Position
Recruiting
Bronchoscopic Airway Clearance for Improving Lung Aeration in Mechanically Ventilated Patients With Atelectasis
Atelectasis, Mechanical Ventilation
Not yet recruitingObservational study
Chest Ultrasound as Diagnostic and Prognostic Tool in Neonatal RDS
Respiratory Distress Syndrome, Newborn, Neonatal Respiratory Distress
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Serap KARACALAR, MD (Doctor of Medicine) principal investigator
Prof. Dr. Cemil Tascıoglu Education and Research Hospital Organization
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Alveolar Recruitment Maneuver in people with Atelectasis and Mechanical Ventilation, run by Prof. Dr. Cemil Tascıoglu Education and Research Hospital Organization at 1 site in Turkey (Türkiye).
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 29 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Incidence of Significant Intraoperative Atelectasis Assessed by Lung Ultrasound (time frame: Immediately prior to tracheal extubation under general anesthesia at the completion of surgery.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07325812, which also lists 7 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Oct 2026.