Evaluation of Postoperative Ventilation Distribution With Electrical Impedance Tomography

Study Overview
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Brief Summary
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Postoperative patients require respiratory management . It is known that the intrapulmonary ventilation distribution becomes uneven due to dorsal atelectasis and ventral hyperinflation during mechanical ventilation management, but the incidence in postoperative patients is unknown. EIT is a device that can monitor the ventilation distribution in the lungs over time without being exposed to the bedside. Therefore, for patients at risk of postoperative respiratory complications, use EIT to 1) evaluate the pulmonary ventilation distribution during postoperative ventilation management, 2) pulmonary ventilation distribution and postoperative respiratory organs. The purpose of this study is to clarify the relationship with the severity of complications. A prospective observational study to investigate the relationship between ventilation distribution and prognosis using EIT in patients undergoing mechanical ventilation after adult surgery.

Official Title
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Evaluation of Ventilation Distribution With Electrical Impedance Tomography in Mechanically Ventilated Patients After Surgery: a Prospective Observational Study

Conditions
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Electrical Impedance Tomography

Participation Criteria
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Eligibility Criteria
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Patients aged 18 years or older who have undergone surgery Patients undergoing mechanical ventilation management when returning to the ICU after surgery High-risk patients with postoperative respiratory complications Exclusion Criteria: the EIT belt is worn Patients with unstable spine or pelvis due to fractures, etc. Patients with implantable defibrillation and implantable pacemaker Patients with skin lesions such as blisters between the 4th and 5th intercostal spaces where Patients with DNR (do-not-resuscitate) Patients undergoing home ventilator management before surgery Preoperative, hypocardiac function patients (echocardiography shows left ventricular ejection fraction of 40% or less, or NYHA III degree or more +) Patients with a ventricular assist device Patients with extracorporeal membrane oxygenation (VV or VA) History of neuromuscular disease

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Association the dorsal fraction of ventilation in EIT and postoperative respiratory complication score | Dorsal fraction of ventilation(%):The dorsal fraction of ventilation is calculated as the sum of all pixel values in the dorsal half of the EIT image over the sum of all pixel values from the EIT image Postoperative pulmonary complications score(0-5):Postoperative pulmonary complications were scored using a grade scale ranging from 0 to 5, with grade zero representing absence of complications, grades 1 to 4 representing increasing (worsening) levels of complications, and grade 5 representing death before hospital discharge. | up to 12 weeks |