The Influence of Different PEEP Levels After Recruitment Maneuvre on the Effect of Alveolar Recruitment Maintenance and Patients' Cardiac Function

Northern Jiangsu People's Hospital

Status

Not yet enrolling

Conditions

Pulmonary Atelectasis

Treatments

Behavioral: lung recruitment maneuvre; PEEP

Study type

Interventional

Funder types

Other

Identifiers

NCT07161466

2024ky380

Details and patient eligibility

About

During general anesthesia surgery, the role of positive end-expiratory pressure (PEEP) in mechanical ventilation remains uncertain. Pressure levels above 0 cm H₂O can prevent postoperative pulmonary complications but may also cause intraoperative circulatory depression and lung injury due to overdistension. Using very low levels of PEEP may lead to atelectasis. However, high levels of PEEP can not only trigger complications such as intraoperative circulatory depression but also promote hyperinflation. Positive end-expiratory pressure (PEEP) is required to prevent atelectasis during lung-protective ventilation, and different levels of PEEP exhibit varying physiological and clinical effects when used alone or in combination with alveolar recruitment maneuvers (ARM). Alveolar recruitment maneuvers (ARM) are used to open atelectatic lung parenchyma, but the duration of their benefits has not been clearly determined. This study aims to determine the effectiveness of different PEEP levels after ARM in general anesthesia surgery, the duration of their time-dependent responses, and their hemodynamic effects, providing a reference for how often recruitment maneuvers should be performed during general anesthesia and further refining the specific details of lung-protective ventilation strategies.

Enrollment

96 estimated patients

Sex

All

Ages

18 to 80 years old

Volunteers

No Healthy Volunteers

Inclusion criteria

ASA physical status classification: Ⅰ or Ⅱ or Ⅲ
Adults aged 18 to 80 years, regardless of gender.
Patients undergoing elective laparoscopic surgery under general anesthesia.
Patients who have provided written informed consent after understanding the study purpose, procedures, and potential risks.

Exclusion criteria

Recent thoracic surgery; chest X - ray or CT indicating pneumothorax, emphysema, or pulmonary bullae;
Pulmonary diseases: asthma, severe obstructive ventilatory dysfunction; preoperative pulse oxygen saturation (SpO2) < 90% in room air or SpO2 < 95% with oxygen supplementation; contraindications for lung recruitment: high intracranial pressure, hypovolemic shock, right heart failure;
Severe heart disease (New York Heart Association, NYHA Class III or IV; acute coronary syndrome or sustained ventricular tachyarrhythmia); participation in other interventional studies or refusal to be enrolled.

Trial design

Primary purpose

Other

Allocation

Randomized

Interventional model

Parallel Assignment

Masking

Double Blind

96 participants in 4 patient groups

A: PEEP=0 cmH2O

Experimental group

Description:

After the patient enters the operating room, routine monitoring of ECG, non-invasive blood pressure, and SpO₂ is performed. Followed by radial artery cannulation for invasive arterial blood pressure monitoring.Then connect the Weijie FloTrac Cardiac Output Monitoring Device. After 3 minutes of pre-oxygenation, tracheal intubation is performed with the following ventilation parameters: VT 6-8 ml/kg, FiO₂ 60%, RR 15 breaths/min, I/E 1:2, and PEEP 4 cmH₂O. Ten minutes after the establishment of pneumoperitoneum during the surgery, baseline levels of respiratory mechanics parameters and hemodynamic variables are recorded. Subsequently, alveolar recruitment is performed at a pressure of 30 cmH₂O for 30 seconds. Immediately after recruitment, the PEEP level is adjusted to 0 cmH2O. The changes in respiratory mechanics parameters and hemodynamic variables after recruitment are recorded. After the outcome indicators recover to the new baseline level, the PEEP is readjusted to 4 cmH₂O.

Treatment:

Behavioral: lung recruitment maneuvre; PEEP

B: PEEP=4cmH2O

Experimental group

Treatment:

Behavioral: lung recruitment maneuvre; PEEP

C: PEEP=8cmH2O

Experimental group

Treatment:

Behavioral: lung recruitment maneuvre; PEEP

D: PEEP=12cmH2O

Experimental group