Effect of Carotid Ultrasound-guided Fluid Management on Anesthetic-induced Hypotension in Elderly Patients Undergoing Gastrointestinal Surgery

Study Overview
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Brief Summary
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The goal of this clinical trial is to learn about Whether carotid ultrasound guided fluid management can reduce the incidence of hypotension after general anesthesia induction in elderly patients undergoing gastrointestinal surgery. The main question[s] it aims to answer are: Whether fluid therapy reduces the incidence of general anaesthesia induced hypotension in elderly patients undergoing gastrointestinal surgery. Whether carotid ultrasound can guide fluid management in elderly patients undergoing gastrointestinal surgery. Participants will use carotid ultrasound to assess volume status. If volume is insufficient, fluid therapy will be selected until volume is sufficient, anesthesia will be then induced. If volume is sufficient, anesthesia will be directly induced. There is a comparison group: No carotid ultrasound will be used to assess the volume status of the patients, and anesthesia will be directly induced.

Official Title
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Effect of Carotid Ultrasound-guided Fluid Management on Anesthetic-induced Hypotension in Elderly Patients Undergoing Gastrointestinal Surgery

Conditions
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Hypotension on Induction

Intervention / Treatment
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* Other: Fluid therapy under the guide of Carotid ultrasound


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 60-80 years old gender unlimited ASA: Grade I-Ⅲ BMI:18-30kg/㎡ Patients undergoing elective gastrointestinal surgery under general anesthesia Informed consent Exclusion Criteria: Carotid artery stenosis ≥50% Patients with heart valve disease Patients with left ventricular ejection fraction < 50% Patients with cardiac dysfunction (NYHA grade Ⅲ-Ⅳ and/or NTproBNP≥900pg/ml) Patients Combined with renal insufficiency (creatinine ≥178μmol/L, and/or blood urea nitrogen > 9mmol/L) Preoperative systolic blood pressure> 160mmHg or diastolic blood pressure > 100mmHg Refuse to participate in the test Patients participating in other clinical trials

Ages Eligible for Study
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Minimum Age: 60 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: This is a randomized controlled clinical study to investigate whether carotid ultrasound-guided fluid therapy reduces the incidence of induced hypotension in elderly patients undergoing gastrointestinal surgery.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: B-Carotid ultrasound guided fluid therapy<br>Participants will use carotid ultrasound to assess volume status. If volume is insufficient, fluid therapy will be selected until volume is sufficient, anesthesia will be then induced. If volume is sufficient, anesthesia will be directly induced. | Other: Fluid therapy under the guide of Carotid ultrasound<br>* Participants will use carotid ultrasound to assess volume status. If volume is insufficient, fluid therapy will be selected until volume is sufficient. If volume is sufficient, no fluid therapy will be given.<br>|
| No Intervention: C-No intervention<br>No carotid ultrasound will be used to assess the volume status of the patients, and anesthesia will be directly induced. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Occurrence of hypotension after anesthesia induction | Hypotension occurred from anesthesia induction to 20 minutes after induction in both groups. | General anesthesia induction from the beginning to 20 minutes after induction | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative acute kidney injury | Postoperative creatinine increased for a short period of time to more than 0.3mg/dl (26.5μmol/L) or to more than 1.5 times the preoperative creatinine concentration. | Within 7 days after surgery | 
| postoperative delirium | Newly diagnosed delirium by the psychiatric department within 30 days after surgery | Within 30 days after surgery | 
| postoperative stroke | Any newly diagnosed postoperative neurological dysfunction within 30 days after surgery. | Within 30 days after surgery |