Postoperative Diaphragm Function in Pediatric Laparoscopic Abdominal Surgery Using Compliance and PEEP Guided by Lung Ultrasound

NCT07126067 | Completed

• 1 other identifier: Study Pedpeep
• Study Type: interventional
• Target: 45
• Locations: 1 country
• Sites: 1

Brief Summary

Protective ventilation strategies and alveolar recruitment maneuvers (ARM) are employed in patients with acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) to improve oxygenation, prevent alveolar collapse, and reduce ventilation-induced lung injury. Recruitment maneuvers aim to open and maintain alveoli. While positive effects on oxygenation have been observed in adults, limited data in children make the clinical efficacy of these strategies uncertain. Careful application and the development of individualized treatment protocols are recommended.

Conditions

PEEP by Lung Ultrasound; PEEP With Dynamic Compliance

Keywords

PEEP; Lung Ulrasound; Laparoscopic surgery; Pediatric patients.

Outcome Measures

Primary Outcomes (3)

• Diaphragm thickness 1

  Diaphragm Thickness Measurement In the supine position, diaphragm thickness will be measured at the junction of the midaxillary line, between the 8th or 9th intercostal spaces on the right side. Using a high-frequency linear probe and ultrasound (DC-60 Diagnostic Ultrasound, Shenzhen Mindray, China), measurements will be recorded during inspiration and expiration. Once a clear diaphragm image is obtained, the skin at the probe's caudal end will be marked with indelible ink. All images will be captured with the probe in the same position. The average of inspiratory and expiratory diaphragm thickness will be used to calculate the diaphragm thickness ratio.

  Baseline measurement prior to anesthesia induction (within 30 minutes before surgery).

• Diaphragm thickness 2

  Diaphragm Thickness Measurement In the supine position, diaphragm thickness will be measured at the junction of the midaxillary line, between the 8th or 9th intercostal spaces on the right side. Using a high-frequency linear probe and ultrasound (DC-60 Diagnostic Ultrasound, Shenzhen Mindray, China), measurements will be recorded during inspiration and expiration. Once a clear diaphragm image is obtained, the skin at the probe's caudal end will be marked with indelible ink. All images will be captured with the probe in the same position. The average of inspiratory and expiratory diaphragm thickness will be used to calculate the diaphragm thickness ratio.

  Immediately after extubation in the operating room (within 5 minutes of extubation).

• Diaphragm thickness 3

  Diaphragm Thickness Measurement In the supine position, diaphragm thickness will be measured at the junction of the midaxillary line, between the 8th or 9th intercostal spaces on the right side. Using a high-frequency linear probe and ultrasound (DC-60 Diagnostic Ultrasound, Shenzhen Mindray, China), measurements will be recorded during inspiration and expiration. Once a clear diaphragm image is obtained, the skin at the probe's caudal end will be marked with indelible ink. All images will be captured with the probe in the same position. The average of inspiratory and expiratory diaphragm thickness will be used to calculate the diaphragm thickness ratio.

  30 minutes after surgery completion (within the postoperative recovery period, up to 30 minutes).

Secondary Outcomes (1)

• Definition and Assessment of Postoperative Pulmonary Complications (PPCs)

  From the end of surgery until 24 hours postoperatively.

Study Arms (3)

Patients who underwent individualized PEEP with lung USG

ACTIVE COMPARATOR

In participants from Group U, PEEP will initially be set at 5 cmH2O and adjusted based on lung ultrasound (USG) findings. If the lung consolidation score is ≥ 2, the PEEP level will be incrementally increased by 2 cmH2O, with USG reassessments every 5 minutes, until a score \< 2 is achieved. This process will be repeated after pneumoperitoneum, peritoneal deflation, and positional changes during surgery to establish an individualized PEEP level. The maximum PEEP value is limited to 20 cmH2O, with a plateau pressure (Pplat) cap of 30 cmH2O and a peak inspiratory pressure (PIP) limit of 40 cmH2O.

Procedure: Lung Ultrasound and PEEP Application

Application of PEEP with Dynamic Compliance

ACTIVE COMPARATOR

PEEP starts at 5 cmH2O after endotracheal intubation. The ventilator (Mindray) will automatically monitor dynamic compliance (TV/Ppeak-PEEP) 5 minutes after endotracheal insertion. PEEP will rise 3 cmH2O. The Cdyn value will be tested again after six breathing cycles, and if it increases, PEEP will be increased by 2 cmH2O. If Cdyn readings decrease during six consecutive automatic measurements, the participant's optimal PEEP level will be the prior measurement's PEEP. To calculate Cdyn-based PEEP, the same technique will be repeated following pneumoperitoneum, peritoneal deflation, and positional changes during operation. For dynamic compliance-based PEEP participants (Group D), the maximum PEEP value will be 20 cmH2O, the plateau pressure (Pplat) limit 30 cmH2O, and the peak inspiratory pressure (PIP) limit 40 cmH2O.

Procedure: Application of PEEP with Dynamic Compliance

Control Group

NO INTERVENTION

Control group participants will receive conventional mechanical ventilation without PEEP modification interventions. PEEP shall stay at 5 cmH2O during surgery unless clinically indicated to change (e.g., substantial hypoxaemia or haemodynamic instability). These subjects will not undergo Cdyn or LUS measures. Instead, institutional protocols will guide intraoperative monitoring and treatment. Depending on clinical measures like oxygen saturation (SpO2), end-tidal carbon dioxide (EtCO2), and arterial blood gas (ABG), the anaesthesiologist may adjust ventilator settings. The control group serves as a baseline for comparison with the intervention groups (LUS or Cdyn-based PEEP adjustments) to determine if individualised PEEP techniques improve clinical results.

Interventions

Lung Ultrasound and PEEP Application PROCEDURE

Application of Lung Ultrasound and PEEP After intubation, PEEP starts at 5 cmH2O. The first lung ultrasound (USG) is performed after 5 minutes. If the lung consolidation score is ≥2, PEEP increases by 2 cmH2O and is reassessed every 5 minutes until the score is \<2. If \<2, PEEP remains unchanged as the optimal level. This process is repeated after pneumoperitoneum, peritoneal deflation, and position changes. In Group U, PEEP is determined by USG, with a maximum of 20 cmH2O, a plateau pressure of 30 cmH2O, and a peak inspiratory pressure of 40 cmH2O.

Patients who underwent individualized PEEP with lung USG

Application of PEEP with Dynamic Compliance PROCEDURE

Application of PEEP with Dynamic Compliance * After endotracheal intubation, PEEP will be applied as 5 cmH2O. * The first dynamic compliance (TV/Ppeak-PEEP) monitoring will be performed automatically by the ventilator (Mindray) 5 minutes after endotracheal intubation, and the PEEP value will be increased by 3 cmH2O. The obtained Cdyn value will be repeated after six respiratory cycles, and if there is an increase, the PEEP value will be increased by 2 cmH2O. When a decreasing trend is observed in the Cdyn value as a result of consecutive automatic measurements of 6 respiratory cycles, the PEEP value applied in the previous measurement will be determined as the most appropriate PEEP value for the participant.

Application of PEEP with Dynamic Compliance

Eligibility Criteria

• Age: 7 Years - 12 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17)

You may qualify if:

• Participants meeting the following criteria will be included in the study:
• Aged 7 to 12 years
• ASA classification I, II, or III
• Undergoing elective laparoscopic abdominal surgery

You may not qualify if:

• Participants with any of the following conditions will be excluded from the study:
• Age \<7 or \>12 years
• ASA classification \> III
• Uncontrolled bronchial asthma
• Presence of bullous lung disease
• Decompensated heart failure (NYHA Stage III-IV)
• History of lung surgery
• Increased intracranial or intraocular pressure
• Advanced hepatic or renal failure
• Parental refusal to participate in the study

Sponsors & Collaborators

• Konya City Hospital: lead

Study Sites (1)

Yasin Tire

Konya, Meram, 42140, Turkey (Türkiye)

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Anesthesiologist

Study Record Dates

• First Submitted: March 2, 2025
• First Posted: August 17, 2025
• Study Start: December 25, 2024
• Primary Completion: June 5, 2025
• Study Completion: July 25, 2025
• Last Updated: August 17, 2025

Record last verified: 2025-08

Locations

TU (1)