Effect of Body Position on Hemodynamics in Patients With Acute Ischemic Stroke Undergoing Ultra-early Reperfusion Therapy

Study Overview
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Brief Summary
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The aim of this study was to determine the differences in hemodynamics between different positions in patients undergoing ultra-early reperfusion therapy.

Detailed Description
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Hemodynamic stability can prevent hypoperfusion or hyperperfusion after reperfusion therapy. It has been reported in a large number of literatures that body position has an effect on hemodynamics, but the effect of different body positions on the hemodynamics of patients undergoing ultra-early reperfusion therapy is not clear. In this study, we hypothesized that the hemodynamics of patients undergoing ultra-early reperfusion therapy would differ between different positions.

Official Title
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Effect of Body Position on Hemodynamics in Patients With Acute Ischemic Stroke Undergoing Ultra-early Reperfusion Therapy

Conditions
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Acute Ischemic Stroke

Intervention / Treatment
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* Device: Transcranial Doppler.


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age≥18 years, < 80 years, regardless of sex； Patients with clinically confirmed acute ischemic stroke who received intravenous thrombolysis or emergency endovascular treatment; Baseline National Institute of Health stroke scale（NIHSS）score ≤25; Baseline Glasgow Coma Scale (GCS) ≥8; Signed and dated informed consent is obtained Exclusion Criteria: The patient has clear indications or contraindications, such as active vomiting, spinal cord injury； Clinicians considered that the assigned body position could not be maintained; Patients unable to cooperate with all noninvasive beat-by-beat continuous BP monitoring; Poor temporal window penetration; Patients with diseases that seriously affect hemodynamics, such as atrial fibrillation, anemia, and hyperthyroidism; Previous history of atrial fibrillation or ECG showing atrial fibrillation or arrhythmia; Pregnant or lactating women; Poor treatment compliance; Complicated with severe systemic diseases, such as heart failure, respiratory failure, renal failure, gastrointestinal bleeding, coagulopathy, malignant tumors.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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: Non-Randomized
Intervention Model: Sequential Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sham Comparator: Zero position<br>All monitoring was done from 9 to 11 a.m., and the whole monitoring process was carried out in a specific and quiet environment at 20-24℃ to avoid other auditory and visual stimuli. After 10min of the relaxed supine position, the blood pressure, heart rate, and blood flow velocity of the middle cerebral artery were measured in the 0° position for 5min. | Device: Transcranial Doppler.<br>* Spontaneous arterial blood pressure will be simultaneously recorded using a servo-controlled plethysmograph on the left or right middle finger with an appropriate finger cuff size. Continuous cerebral blood flow velocities of bilateral middle cerebral artery will be assessed noninvasively using transcranial Doppler.<br>|
| Experimental: 30 degrees position<br>Within 30 seconds after the 0° position measurement completion, the subjects were transferred to the 30° position and rested for 15 minutes under the 30° position. In other words, a washout period of 15 minutes was established between two measurements to ensure the stability of vital signs and avoid confounding effects. The blood pressure, heart rate, and blood flow velocity of the middle cerebral artery were measured again for 5 minutes after the vital signs were stable. | Device: Transcranial Doppler.<br>* Spontaneous arterial blood pressure will be simultaneously recorded using a servo-controlled plethysmograph on the left or right middle finger with an appropriate finger cuff size. Continuous cerebral blood flow velocities of bilateral middle cerebral artery will be assessed noninvasively using transcranial Doppler.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Differences in blood pressure variability（BPV）between different positions | BPV is defined as blood pressure oscillations in relation to the mean values. | 0-7 days | 
| Differences in heart rate variability (HRV) between different positions | HRV is defined as heart rate oscillations in relation to the mean values. | 0-7 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The difference of middle cerebral artery blood flow velocity between different positions. | Continuous cerebral blood flow velocities of bilateral middle cerebral artery will be assessed noninvasively using transcranial Doppler. | 0-7 days |