Obesity, Postoperative Pulmonary Complications, Mechanical Ventilation
Conditions
Brief summary
This study aims to compare standard positive end-expiratory pressure (PEEP) with dynamic compliance-guided individualized PEEP in obese patients undergoing elective spinal surgery under general anesthesia. Obesity and prone positioning during spinal surgery are associated with reduced lung compliance, atelectasis, and an increased risk of postoperative pulmonary complications. Participants will be allocated to receive either a fixed standard PEEP or an individualized PEEP level determined according to intraoperative dynamic lung compliance. Intraoperative oxygenation, respiratory mechanics, arterial blood gas parameters, and hemodynamic variables will be assessed at predefined time points. Postoperative pulmonary complications within the first 24 hours after surgery will also be evaluated. The study seeks to determine whether individualized PEEP titration based on dynamic compliance offers physiological or clinical advantages compared with a standard PEEP strategy in this patient population.
Interventions
DEVICEStandard PEEP
Application of a fixed positive end-expiratory pressure of 5 cmH₂O during intraoperative mechanical ventilation.
Sponsors
Konya City Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
Participants are assigned to one of two parallel groups receiving either standard fixed PEEP or dynamic compliance-guided individualized PEEP during surgery.
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* Adult patients aged 18-65 years * Body mass index (BMI) ≥30 kg/m² * Scheduled for elective spinal surgery under general anesthesia * Requirement for intraoperative mechanical ventilation * American Society of Anesthesiologists (ASA) physical status II-III * Provision of written informed consent
Exclusion criteria
* Pre-existing severe pulmonary disease (e.g., COPD GOLD stage III-IV, restrictive lung disease) * Severe cardiac disease (e.g., heart failure with reduced ejection fraction, significant valvular disease) * History of thoracic surgery affecting lung mechanics * Pregnancy * Emergency surgery * Intraoperative need for deviation from the planned ventilation protocol
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Intraoperative Oxygenation (PaO₂/FiO₂ Ratio) | From induction of anesthesia until the end of surgery | The primary outcome is intraoperative oxygenation assessed by the arterial partial pressure of oxygen to fraction of inspired oxygen (PaO₂/FiO₂) ratio during mechanical ventilation. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Dynamic Lung Compliance | From induction of anesthesia until the end of surgery | Dynamic lung compliance (mL/cmH₂O) measured intraoperatively via ventilator respiratory mechanics monitoring. |
| Static Lung Compliance | From induction of anesthesia until the end of surgery | Static lung compliance (mL/cmH₂O) measured intraoperatively via ventilator plateau pressure analysis. |
| Peak Airway Pressure | From induction of anesthesia until the end of surgery | Peak inspiratory airway pressure (cmH₂O) measured intraoperatively using ventilator monitoring. |
| Plateau Airway Pressure | From induction of anesthesia until the end of surgery | Plateau airway pressure (cmH₂O) measured intraoperatively during mechanical ventilation. |
Countries
Turkey (Türkiye)
Outcome results
None listed