NCT05187039

Bariatric Electrical Impedance Tomography

Evaluation of Atelectasis Formation and Regression With Electrical Impedance Tomography in the Perioperative Phase of Obese Patients Scheduled for Laparoscopic Bariatric Surgery

• Status: Completed
• Phase: —
• Study type: Observational
• Enrollment: 30 (actual)
• Sponsor: Insel Gruppe AG, University Hospital Bern · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This study investigates under controlled conditions the variation of poorly ventilated lung units (silent spaces) in obese patients scheduled for laparoscopic bariatric surgery in the perioperative phase.

Detailed description

Eligible patients with written informed consent, scheduled for laparoscopic bariatric surgery. As for standard of care no premedication will be given for bariatric patients. Patients will be monitored according the local standard. Thoracic electrical impedance tomography measurements (each measurement will last 1 min) will be performed at the following time points: before induction of the anaesthesia; before the surgical procedure when the induction is terminated and recruitment manoeuvers have been performed; after the termination of the surgical procedure; before transport to the Post anaesthesia Care Unit (PACU); before the discharge from the PACU after 2 hours of monitoring. An additional thoracic electrical impedance tomography measurement (duration 1 min) will be performed before discharge at home. For this, resulting potential differences are measured, and impedance distribution sampled at 30 Hz will be calculated by an automated linearized Newton-Raphson reconstruction algorithm. Relative change in poorly ventilated lung regions (silent spaces) and end-expiratory lung impedance (EELI) and measures of ventilation inhomogeneity such as the global inhomogeneity index will be calculated.

Conditions

• Anesthesia

Interventions

Type	Name	Description
OTHER	Electrical impedance tomography during anesthesia	Thoracic electrical impedance tomography measurements ( min each) will be performed at the following time points: before induction of the anaesthesia; before the surgical procedure when the induction is terminated and recruitment manoeuvers have been performed; after the termination of the surgical procedure; before transport to the Post anaesthesia Care Unit (PACU); before the discharge from the PACU after 2 hours of monitoring. An additional thoracic EIT-measurement will be performed before discharge at home. For this, resulting potential differences are measured, and impedance distribution sampled at 30 Hz will be calculated. Relative change in poorly ventilated lung regions (silent spaces) and end-expiratory lung impedance (EELI) and measures of ventilation inhomogeneity will be calculated using customised code (Matlab R2021a, The MathWorks, Nattick, Massachusetts, USA).

Timeline

• Start date: 2021-10-19
• Primary completion: 2022-11-01
• Completion: 2023-03-08
• First posted: 2022-01-11
• Last updated: 2023-03-09

Locations

1 site across 1 country: Switzerland