Cuff Pressure and Airway Edema in CABG With CPB

Purpose This study aims to evaluate the effect of endotracheal tube (ETT) cuff pressure management during cardiopulmonary bypass (CPB) in coronary artery bypass grafting (CABG) surgery on the development of upper airway edema. Ultrasonography will be used to assess changes in lateral pharyngeal wall (LPW) thickness, tongue thickness, correlation between intravenous fluid volume at multiple perioperative time points.

Study Design

This is a prospective, randomized, double-blind, controlled clinical trial. Patients undergoing elective CABG with CPB will be randomly assigned into two groups:

Group 1: ETT cuff pressure maintained at 0 mmHg during CPB Group 2: ETT cuff pressure maintained at 20-30 mmHg during CPB Cuff pressures will be monitored with a manometer every 5 minutes and adjusted as needed. At the end of CPB, all patients will have standard cuff pressure (20-30 mmHg).

Outcomes Primary outcome: Changes in LPW thickness as a marker of upper airway edema assessed by ultrasonography at five time points (T0: Preoperative T1: Before initiation of CPB T2: At the end of CPB T3: 2nd postoperative hour).

Secondary outcomes: Changes in tongue thickness, correlation between intravenous fluid volume and airway edema.

Participation Approximately 76 patients (18-80 years, ASA III-IV) scheduled for elective CABG with CPB will be enrolled.

Inclusion criteria

• Patients scheduled for elective coronary artery bypass grafting (CABG) surgery
• Aged 18-80 years
• ASA physical status class III-IV
• Providing written informed consent

Exclusion criteria

• History of difficult intubation
• Anatomical abnormalities of the upper airway
• Body mass index (BMI) > 35 kg/m²
• Acute respiratory tract infection
• Emergency surgeries