Effects of Different Anesthesia Machine Modalities on Bariatric Surgery Patients: a Prospective Randomized Controlled Study

Yu-Long Jia

Status: Enrolling

Conditions: Ventilation; Intracranial Pressure; Carbon Dioxide; Bariatric Surgery

Treatments: Device: PRVC Ventilation mode; Device: PC Ventilation mode; Device: VC Ventilation mode

Study type: Interventional

Funder types: Other

Identifiers

NCT06547411

MER-068

Details and patient eligibility

About

The goal of this clinical trial is to explore the clinical significance and value of the PRVC ventilation mode in Bariatric Surgery Patients. The main questions it aims to answer are：

• Do different ventilation patterns affect intracranial pressure and partial pressure of carbon dioxide in bariatric surgery patients?
• Does PRVC mode reduce intracranial pressure and partial pressure of carbon dioxide in bariatric surgery patients?
• Whether intracranial pressure can be quickly measured by monitoring a patient's optic nerve sheath diameter (ONSD)？ Researchers randomized bariatric surgery patients into PC, VC, and PRVC groups for comparison, looking at breathing mechanics, PaCO2, and ICP.

Participants will:

• take PC mode ventilation, VC mode ventilation, and PRVC mode ventilation
• monitor Respiratory mechanics, PaCO2, and ONSD

Enrollment: 90 estimated patients

Sex: All

Ages: 16 to 65 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Patients scheduled for elective bariatric surgery.
• Age between 16 and 65 years.
• Continuous weight gain for more than 5 years with a BMI ≥ 35.
• ASA-PS (American Society of Anesthesiologists Physical Status) categorization of Grade II or III.

Exclusion criteria

• Patients who were dependent on alcohol or opioids.
• Patients with severe mental or intellectual disabilities.
• Patients with severe ocular conditions, such as ocular trauma, optic nerve tumors, or those wearing ocular prostheses.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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90 participants in 3 patient groups

PC Ventilation mode group

Experimental group

Description:

Group I patients received mechanical ventilation using the PC mode. The anesthetic machine (MAQUET Flow-I, Italy) parameters were set as follows: The inspiratory pressure (Pins) was adjusted to maintain an end-tidal carbon dioxide concentration (ETCO2) of 4.0-5.0 kPa. Pure oxygen and air were utilized at 0.3 L/min each, with an oxygen content of 41%.

Treatment:

Device: PC Ventilation mode

VC Ventilation mode group

Experimental group

Description:

Group II patients received mechanical ventilation in VC mode. The tidal volume during regulated breathing was determined based on the ideal body weight (IBW): 6-8 ml/kg (IBW for males: 50 + 0.91 × (height \[cm\] - 152.4); IBW for females: 45.5 + 0.91 × (height \[cm\] - 152.4). The positive end-expiratory pressure (PEEP) was set at 10 cmH2O, with an inspiration-to-expiration ratio of 1:2, a respiratory rate of 16 breaths per minute, and an oxygen content of 41%

Treatment:

Device: VC Ventilation mode

PRVC Ventilation mode group

Experimental group

Description:

Group III patients received mechanical ventilation using the PRVC mode.The tidal volume during regulated breathing was determined based on the ideal body weight (IBW): 6-8 ml/kg (IBW for males: 50 + 0.91 × (height \[cm\] - 152.4); IBW for females: 45.5 + 0.91 × (height \[cm\] - 152.4). The positive end-expiratory pressure (PEEP) was set at 10 cmH2O, with an inspiration-to-expiration ratio of 1:2, a respiratory rate of 16 breaths per minute, and an oxygen content of 41%

Treatment:

Device: PRVC Ventilation mode