Trial Outcomes & Findings for Evaluation of the Effects of Intraoperative Ventilation Modes on Perioperative Atelectasis (NCT NCT07413575)
NCT ID: NCT07413575
Last Updated: 2026-05-19
Results Overview
Perioperative atelectasis was assessed as the change in Lung Ultrasound Score (ΔLUS) from preoperative baseline to 24 hours postoperatively. Lung aeration was evaluated using a standardized 12-region scoring system (0-36 scores on a scale). ΔLUS was calculated as postoperative LUS at 24 hours minus preoperative baseline LUS. Higher values indicate greater loss of aeration.
Recruitment status
COMPLETED
Target enrollment
78 participants
Primary outcome timeframe
Preoperative baseline and 24 hours postoperatively
Results posted on
2026-05-19
Participant Flow
Participants were recruited from patients scheduled for elective laparoscopic hysterectomy at Sehit Prof. Dr. Ilhan Varank Sancaktepe Training and Research Hospital between September 15, 2024 and August 05, 2025. All eligible patients meeting inclusion criteria were consecutively assessed for participation. A total of 78 patients were enrolled in the study.
A total of 78 participants were enrolled. Seventy-five participants completed the study and were included in the final analysis.
Participant milestones
| Measure |
Flow-Controlled Ventilation (FCV)
Participants who received flow-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
Pressure-Controlled Ventilation (PCV)
Participants who received pressure-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
Volume-Controlled Ventilation (VCV)
Participants who received volume-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
|---|---|---|---|
|
Overall Study
STARTED
|
26
|
25
|
27
|
|
Overall Study
not completed
|
1
|
0
|
2
|
|
Overall Study
COMPLETED
|
25
|
25
|
25
|
|
Overall Study
NOT COMPLETED
|
1
|
0
|
2
|
Reasons for withdrawal
| Measure |
Flow-Controlled Ventilation (FCV)
Participants who received flow-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
Pressure-Controlled Ventilation (PCV)
Participants who received pressure-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
Volume-Controlled Ventilation (VCV)
Participants who received volume-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
|---|---|---|---|
|
Overall Study
Adverse Event
|
1
|
0
|
2
|
Baseline Characteristics
Race and Ethnicity were not collected from any participant.
Baseline characteristics by cohort
| Measure |
Flow-Controlled Ventilation (FCV)
n=25 Participants
Patients were divided into three groups according to the type of ventilation used. The group that received flow-controlled ventilation was designated as the FCV group. In the FCV group, a constant flow is applied during both inspiration and expiration. In all three groups, lung ultrasonographic evaluation was performed preoperatively and up to 24 hours postoperatively, and the lung ultrasound scores were determined. Vital signs, ventilation parameters, blood gas analysis, and pain scores were also recorded at specific time intervals.
|
Pressure-Controlled Ventilation (PCV)
n=25 Participants
Patients were divided into three groups according to the type of ventilation used. The group that received pressure-controlled ventilation was designated as the PCV group. In the PCV group, the peak airway pressure is controlled. The mandatory respiratory rate and inspiratory time are also adjusted. In all three groups, lung ultrasonographic evaluation was performed preoperatively and up to 24 hours postoperatively, and the lung ultrasound scores were determined. Vital signs, ventilation parameters, blood gas analysis, and pain scores were also recorded at specific time intervals.
|
Volume-Controlled Ventilation (VCV)
n=25 Participants
Patients were divided into three groups according to the ventilation mode used. The group receiving volume-controlled ventilation (VCV) was designated as the VCV group. In the VCV group, a specific tidal volume (Vt) was achieved by maintaining a constant flow rate and inspiratory time set on the ventilator, while airway pressure was allowed to vary. In all three groups, lung ultrasonographic evaluation was performed preoperatively and up to 24 hours postoperatively, and lung ultrasound scores were determined. Vital signs, ventilation parameters, blood gas analysis results, and pain scores were recorded at predefined time intervals.
|
Total
n=75 Participants
Total of all reporting groups
|
|---|---|---|---|---|
|
Age, Continuous
|
49.84 years
STANDARD_DEVIATION 6.33 • n=25 Participants
|
50.32 years
STANDARD_DEVIATION 6.29 • n=25 Participants
|
53.40 years
STANDARD_DEVIATION 7.65 • n=25 Participants
|
51.18 years
STANDARD_DEVIATION 6.83 • n=75 Participants
|
|
Sex: Female, Male
Female
|
25 Participants
n=25 Participants
|
25 Participants
n=25 Participants
|
25 Participants
n=25 Participants
|
75 Participants
n=75 Participants
|
|
Sex: Female, Male
Male
|
0 Participants
n=25 Participants
|
0 Participants
n=25 Participants
|
0 Participants
n=25 Participants
|
0 Participants
n=75 Participants
|
|
Race and Ethnicity Not Collected
|
—
|
—
|
—
|
0 Participants
Race and Ethnicity were not collected from any participant.
|
|
Baseline Lung Ultrasound Score (LUS)
|
1.60 scores on a scale
STANDARD_DEVIATION 1.66 • n=25 Participants
|
1.96 scores on a scale
STANDARD_DEVIATION 1.31 • n=25 Participants
|
2.00 scores on a scale
STANDARD_DEVIATION 1.85 • n=25 Participants
|
1.85 scores on a scale
STANDARD_DEVIATION 1.61 • n=75 Participants
|
PRIMARY outcome
Timeframe: Preoperative baseline and 24 hours postoperativelyPerioperative atelectasis was assessed as the change in Lung Ultrasound Score (ΔLUS) from preoperative baseline to 24 hours postoperatively. Lung aeration was evaluated using a standardized 12-region scoring system (0-36 scores on a scale). ΔLUS was calculated as postoperative LUS at 24 hours minus preoperative baseline LUS. Higher values indicate greater loss of aeration.
Outcome measures
| Measure |
Flow-Controlled Ventilation (FCV)
n=25 Participants
Participants who received flow-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
Pressure-Controlled Ventilation (PCV)
n=25 Participants
Participants who received pressure-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
Volume-Controlled Ventilation (VCV)
n=25 Participants
Participants who received volume-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
|---|---|---|---|
|
Change in Lung Ultrasound Score (ΔLUS) From Preoperative Baseline to 24 Hours Postoperatively
|
4.92 scores on a scale
Standard Deviation 3.49
|
3.88 scores on a scale
Standard Deviation 1.69
|
5.20 scores on a scale
Standard Deviation 2.24
|
SECONDARY outcome
Timeframe: Intraoperative periodMechanical power calculated from ventilator parameters at predefined intraoperative time points.
Outcome measures
| Measure |
Flow-Controlled Ventilation (FCV)
n=25 Participants
Participants who received flow-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
Pressure-Controlled Ventilation (PCV)
n=25 Participants
Participants who received pressure-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
Volume-Controlled Ventilation (VCV)
n=25 Participants
Participants who received volume-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
|---|---|---|---|
|
Mechanical Power During Intraoperative Ventilation
Mechanical Power Before Trendelenburg Positioning
|
8.54 J/min
Standard Deviation 1.47
|
7.48 J/min
Standard Deviation 2.18
|
7.7 J/min
Standard Deviation 2.2
|
|
Mechanical Power During Intraoperative Ventilation
Mechanical Power After Trendelenburg Positioning
|
9.49 J/min
Standard Deviation 1.95
|
8.43 J/min
Standard Deviation 2.51
|
8.31 J/min
Standard Deviation 2.11
|
|
Mechanical Power During Intraoperative Ventilation
Mechanical Power 30 Minutes After Trendelenburg Positioning
|
9.48 J/min
Standard Deviation 1.93
|
8.63 J/min
Standard Deviation 2.59
|
8.8 J/min
Standard Deviation 1.85
|
|
Mechanical Power During Intraoperative Ventilation
Mechanical Power 60 Minutes After Trendelenburg Positioning
|
9.45 J/min
Standard Deviation 1.71
|
8.88 J/min
Standard Deviation 2.21
|
9.04 J/min
Standard Deviation 1.73
|
|
Mechanical Power During Intraoperative Ventilation
Mechanical Power 90 Minutes After Trendelenburg Positioning
|
9.57 J/min
Standard Deviation 1.72
|
8.97 J/min
Standard Deviation 2.33
|
9.06 J/min
Standard Deviation 1.98
|
|
Mechanical Power During Intraoperative Ventilation
Mechanical Power 120 Minutes After Trendelenburg Positioning
|
7.57 J/min
Standard Deviation 1.45
|
6.96 J/min
Standard Deviation 1.32
|
7.15 J/min
Standard Deviation 1.61
|
|
Mechanical Power During Intraoperative Ventilation
Mechanical Power After Pneumoperitoneum
|
8.36 J/min
Standard Deviation 1.6
|
7.59 J/min
Standard Deviation 2.14
|
7.54 J/min
Standard Deviation 2.07
|
|
Mechanical Power During Intraoperative Ventilation
Mechanical Power After Anesthesia Induction
|
7.05 J/min
Standard Deviation 1.44
|
6.48 J/min
Standard Deviation 1.39
|
6.47 J/min
Standard Deviation 1.42
|
|
Mechanical Power During Intraoperative Ventilation
Mechanical Power Before Pneumoperitoneum
|
7.00 J/min
Standard Deviation 1.32
|
6.03 J/min
Standard Deviation 1.26
|
6.24 J/min
Standard Deviation 1.50
|
SECONDARY outcome
Timeframe: Preoperative and at the time of transfer from the Post-Anesthesia Care Unit (PACU) to the ward (PACU discharge).PaO₂ measured by arterial blood gas analysis at preoperative baseline and at the time of discharge from the Post-Anesthesia Care Unit (PACU).
Outcome measures
| Measure |
Flow-Controlled Ventilation (FCV)
n=25 Participants
Participants who received flow-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
Pressure-Controlled Ventilation (PCV)
n=25 Participants
Participants who received pressure-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
Volume-Controlled Ventilation (VCV)
n=25 Participants
Participants who received volume-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
|---|---|---|---|
|
Arterial Oxygen Partial Pressure (PaO₂)
Preoperative Arterial Oxygen Partial Pressure (PaO₂)
|
91.64 mmHg
Standard Deviation 3.96
|
90.96 mmHg
Standard Deviation 3.90
|
90.28 mmHg
Standard Deviation 3.96
|
|
Arterial Oxygen Partial Pressure (PaO₂)
Arterial Oxygen Partial Pressure (PaO₂) in the Post-Anesthesia Care Unit (PACU)
|
101.08 mmHg
Standard Deviation 14.49
|
87.88 mmHg
Standard Deviation 5.19
|
85.28 mmHg
Standard Deviation 4.72
|
SECONDARY outcome
Timeframe: Preoperative and at the time of transfer from the Post-Anesthesia Care Unit (PACU) to the ward (PACU discharge).PaO₂/FiO₂ ratio was calculated from arterial blood gas analysis using PaO₂ and the fraction of inspired oxygen (FiO₂) at preoperative baseline and at the time of discharge from the Post-Anesthesia Care Unit (PACU).
Outcome measures
| Measure |
Flow-Controlled Ventilation (FCV)
n=25 Participants
Participants who received flow-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
Pressure-Controlled Ventilation (PCV)
n=25 Participants
Participants who received pressure-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
Volume-Controlled Ventilation (VCV)
n=25 Participants
Participants who received volume-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
|---|---|---|---|
|
PaO₂/FiO₂ Ratio
Preoperative PaO₂/FiO₂ Ratio
|
435.96 ratio
Standard Deviation 18.82
|
432.76 ratio
Standard Deviation 18.6
|
429.48 ratio
Standard Deviation 18.91
|
|
PaO₂/FiO₂ Ratio
PaO₂/FiO₂ Ratio in the Post-Anesthesia Care Unit (PACU)
|
480.84 ratio
Standard Deviation 69.11
|
417.88 ratio
Standard Deviation 24.68
|
405.6 ratio
Standard Deviation 22.45
|
OTHER_PRE_SPECIFIED outcome
Timeframe: Preoperative baseline, at discharge from the Post-Anesthesia Care Unit (PACU), and at 2 hours postoperativelyChange in Lung Ultrasound Score (ΔLUS) calculated as postoperative LUS minus preoperative baseline LUS. Lung aeration was assessed using a standardized 12-region scoring system (0-36 points). Positive values indicate increased loss of aeration. Measurements were obtained at PACU discharge and at postoperative 2 hours.
Outcome measures
| Measure |
Flow-Controlled Ventilation (FCV)
n=25 Participants
Participants who received flow-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
Pressure-Controlled Ventilation (PCV)
n=25 Participants
Participants who received pressure-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
Volume-Controlled Ventilation (VCV)
n=25 Participants
Participants who received volume-controlled ventilation during laparoscopic hysterectomy as determined by the attending anesthesiologist as part of routine clinical practice.
|
|---|---|---|---|
|
Change in Lung Ultrasound Score (ΔLUS) During Early Postoperative Period
Change in LUS at Postoperative 2 Hours From Baseline
|
7.60 scores on a scale
Standard Deviation 3.27
|
7.52 scores on a scale
Standard Deviation 2.89
|
8.84 scores on a scale
Standard Deviation 3.12
|
|
Change in Lung Ultrasound Score (ΔLUS) During Early Postoperative Period
Change in LUS at PACU From Baseline
|
9.24 scores on a scale
Standard Deviation 3.68
|
9.68 scores on a scale
Standard Deviation 3.05
|
11.20 scores on a scale
Standard Deviation 3.92
|
Adverse Events
Flow-Controlled Ventilation (FCV)
Serious events: 0 serious events
Other events: 1 other events
Deaths: 0 deaths
Pressure-Controlled Ventilation (PCV)
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Volume-Controlled Ventilation (VCV)
Serious events: 0 serious events
Other events: 2 other events
Deaths: 0 deaths
Serious adverse events
Adverse event data not reported
Other adverse events
| Measure |
Flow-Controlled Ventilation (FCV)
n=26 participants at risk
Patients were divided into three groups according to the type of ventilation used. The group that received flow-controlled ventilation was designated as the FCV group. In the FCV group, a constant flow is applied during both inspiration and expiration. In all three groups, lung ultrasonographic evaluation was performed preoperatively and up to 24 hours postoperatively, and the lung ultrasound scores were determined. Vital signs, ventilation parameters, blood gas analysis, and pain scores were also recorded at specific time intervals.
|
Pressure-Controlled Ventilation (PCV)
n=25 participants at risk
Patients were divided into three groups according to the type of ventilation used. The group that received pressure-controlled ventilation was designated as the PCV group. In the PCV group, the peak airway pressure is controlled. The mandatory respiratory rate and inspiratory time are also adjusted. In all three groups, lung ultrasonographic evaluation was performed preoperatively and up to 24 hours postoperatively, and the lung ultrasound scores were determined. Vital signs, ventilation parameters, blood gas analysis, and pain scores were also recorded at specific time intervals.
|
Volume-Controlled Ventilation (VCV)
n=27 participants at risk
Patients were divided into three groups according to the ventilation mode used. The group receiving volume-controlled ventilation (VCV) was designated as the VCV group. In the VCV group, a specific tidal volume (Vt) was achieved by maintaining a constant flow rate and inspiratory time set on the ventilator, while airway pressure was allowed to vary. In all three groups, lung ultrasonographic evaluation was performed preoperatively and up to 24 hours postoperatively, and lung ultrasound scores were determined. Vital signs, ventilation parameters, blood gas analysis results, and pain scores were recorded at predefined time intervals.
|
|---|---|---|---|
|
General disorders
Perioperative complications
|
3.8%
1/26 • Number of events 1 • From anesthesia induction until completion of the 24-hour postoperative follow-up period.
Adverse events were defined as perioperative complications occurring during surgery or within the first 24 hours postoperatively. Data were obtained from routine clinical monitoring and medical records. Participants withdrawn due to perioperative complications were included in the adverse event reporting.
|
0.00%
0/25 • From anesthesia induction until completion of the 24-hour postoperative follow-up period.
Adverse events were defined as perioperative complications occurring during surgery or within the first 24 hours postoperatively. Data were obtained from routine clinical monitoring and medical records. Participants withdrawn due to perioperative complications were included in the adverse event reporting.
|
7.4%
2/27 • Number of events 2 • From anesthesia induction until completion of the 24-hour postoperative follow-up period.
Adverse events were defined as perioperative complications occurring during surgery or within the first 24 hours postoperatively. Data were obtained from routine clinical monitoring and medical records. Participants withdrawn due to perioperative complications were included in the adverse event reporting.
|
Additional Information
Dr. Tuğçe Türkan Tanman
Sehit Prof. Dr. Ilhan Varank Sancaktepe Training and Research Hospital, University of Health Sciences
Phone: +90 539 760 29 40
Email: [email protected]
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place