Effects of Permissive Hypercapnia on Concentration of Postoperative Plasma Neurofilament Light

Study Overview
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Brief Summary
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The aim of this study is to conduct a prospective, single-center randomized controlled study to investigate the changes of plasma NFL concentration in patients undergoing laparoscopic surgery with mild hypercapnia, and further explore its impact on the central nervous system.

Detailed Description
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Plasma NFL concentrations were measured preoperatively and 1 day postoperatively. Secondary endpoints:MMSE (Mini-Mental State Exam) and CAM (Confusion Assessment Method) is conducted to check the subjects' baseline cognitive function preoperative day and 0 to 7 postoperative day twice a day to assess whether delirium occurs.

Official Title
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Effects of Permissive Hypercapnia on Concentration of Postoperative Plasma Neurofilament Light in Elderly Patients Undergoing Laparoscopic Surgery:A Prospective, Randomized Controlled Study

Conditions
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Hypercapnia

Intervention / Treatment
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* Behavioral: permissive hypercapnia
* Behavioral: normocapnia


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age over 60 years surgery of greater than 90 min American Society of Anesthesiology (ASA) status Ⅱ-Ⅲ undergoing laparoscopic surgery under general anesthesia with endotracheal intubation Exclusion Criteria: history of mental or neurological disorders preoperative use of antipsychotic drugs American Society of Anesthesiology (ASA) status Ⅳ severe abnormalities in heart, lung, liver, kidney, and coagulation function Intracranial space-occupying lesions or major cerebrovascular diseases (such as carotid atherosclerosis and cerebral aneurysm) Severe hypertension or hypotension Severe metabolic acidosis or hypercapnic respiratory failure before surgery

Ages Eligible for Study
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Minimum Age: 60 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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: permissive hypercapnia<br>Tidal volume (6-8ml/kg) and respiratory rate is adjusted to achieve the objective values of PaCO2≥46 mmHg | Behavioral: permissive hypercapnia<br>* Tidal volume (6-8ml/kg) and respiratory rate is adjusted to achieve the objective values of PaCO2≥46 mmHg<br>* Other names: PaCO2≥46 mmHg;|
| Active Comparator: normocapnia<br>Tidal volume (8-10ml/kg) and respiratory rate is adjusted to achieve the objective values of PaCO2:35～45mmHg | Behavioral: normocapnia<br>* Tidal volume (8-10ml/kg) and respiratory rate is adjusted to achieve the objective values of PaCO2:35～45mmHg<br>* Other names: PaCO2:35～45mmHg;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in plasma Neurofilament Light levels | Comparison of changes in plasma Neurofilament Light levels pre and postoperative in patients exposed and not exposed to hypercapnia. | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Neurofilament light, Hypercapnia