Deep Breathing With and Without Pressure Support and PEEP for Preoxygenation in Obese Patients

Pamukkale University

Status: Completed

Conditions: Obesity

Treatments: Procedure: Positive End-Expiratory Pressure; Procedure: Pressure Support Ventilation; Procedure: Deep Breathing Preoxygenation

Study type: Interventional

Funder types: Other

Identifiers

NCT07380425

PamukkaleUCTanriverdi-002

Details and patient eligibility

About

Obese patients are at increased risk of low oxygen levels during the induction of general anesthesia. Preoxygenation with a face mask before anesthesia is routinely used to increase oxygen reserves. This study compares three preoxygenation techniques: deep breathing alone, deep breathing with pressure-supported ventilation, and deep breathing with pressure-supported ventilation plus positive end-expiratory pressure (PEEP).

The main goal of the study is to determine how quickly each technique allows patients to reach an adequate level of oxygen in the lungs. In addition, the study evaluates whether these techniques cause gastric distension, which could increase the risk of regurgitation. Gastric ultrasound is used to assess stomach size before and after preoxygenation.

The results of this study will help identify the most effective and safest method of preoxygenation in obese patients undergoing elective surgery.

Enrollment: 75 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age ≥ 18 years
• Obesity
• Scheduled for elective surgery under general anesthesia
• Able to cooperate with deep breathing during preoxygenation

Exclusion criteria

• Hemodynamic instability
• Poor cooperation
• Preoperative oxygen therapy requirement
• Conditions in which positive pressure ventilation may be harmful (e.g., increased intracranial or intraocular pressure)
• Pregnancy
• Emergency surgery
• Beard (preventing adequate face mask seal)
• Previous gastric surgery
• Inability to visualize the gastric antrum by ultrasonography

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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75 participants in 3 patient groups

DB (Deep Breathing)

Experimental group

Description:

Deep breathing preoxygenation with 100% oxygen at 12 L/min using.

Treatment:

Procedure: Positive End-Expiratory Pressure

DB+PSV

Experimental group

Description:

Preoxygenation with deep breathing supported by pressure-supported ventilation (PSV-Pro) with 12 cmH₂O pressure support and 100% oxygen at 12 L/min until EtO₂ reached 90%.

Treatment:

Procedure: Deep Breathing Preoxygenation

DB+PSV+PEEP

Experimental group

Description:

Deep breathing preoxygenation supported by PSV-Pro (pressure support 12 cmH₂O) with the addition of PEEP 6 cmH₂O; 100% oxygen at 12 L/min. This arm differs from Arm 2 by the application of PEEP.

Treatment:

Procedure: Pressure Support Ventilation