Biphasic Effects of Different Doses Ephedrine on Hemodynamics in Elderly Patients Under General Anesthesia

Study Overview
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Brief Summary
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Ephedrine is commonly clinically vasoactive drugs, which can constrict blood vessels and increase blood pressure. Ephedrine can not only stimulate α receptors, but also β receptors, that's to say, it can increase heart rate, stroke volume, and cardiac output, but it also can decrease the level of systemic vascular resistance. This research aims to observe the short-term vasodilator effect of diffierent doses of ephedrine used in elderly patients under general anesthesia in clinical practice, and analyze the main reasons for this phenomenon and take preventive actions to minimize the possibility of further lowering of blood pressure to provide references for clinical rational use of drugs.

Official Title
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Biphasic Effects of Different Doses Ephedrine on Hemodynamics in Elderly Patients Under General Anesthesia

Conditions
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Blood Pressure

Intervention / Treatment
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* Drug: Ephedrine
* Drug: Ephedrine
* Drug: Ephedrine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Ages ranged from 65 to 80 ASA I II patients undergoing elective general anesthesia BMI 18.5-30.0 Exclusion Criteria: refusal of patients emergency surgery, neurological or mental disorders , Liver and kidney dysfunction previous allergy to ephedrine and phenylephrine heart disease history, such as pacemaker implantation, unstable angina, congestive heart failure, Heart valve disease nerve, digestive, endocrine system diseases, and affect intravascular Fluid volume or balance diseases (such as inflammatory diseases or gastrointestinal obstructive diseases) emergency surgery malignant tumors tachycardia (HR>100) bradycardia ( HR<50) intraoperative hypotension that is difficult to correct with ephedrine and phenylephrine use of other vasoactive drugs. surgery time <40 min

Ages Eligible for Study
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Minimum Age: 65 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
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: ephedrine (4mg)<br> | Drug: Ephedrine<br>* When elderly patients had hypotension (invasive blood pressure drops >20% from the baseline value or <100 mmHg, or MAP <70mmHg) 20 minutes after anesthesia induction, 4 mg ephedrine in 10 ml saline was usd Intravenously<br>|
| Experimental: ephedrine (8mg)<br> | Drug: Ephedrine<br>* When elderly patients had hypotension (invasive blood pressure drops >20% from the baseline value or <100 mmHg, or MAP <70mmHg) 20 minutes after anesthesia induction, 8 mg ephedrine in 10 ml saline was usd Intravenously<br>|
| Experimental: ephedrine (12mg)<br> | Drug: Ephedrine<br>* When elderly patients had hypotension (invasive blood pressure drops >20% from the baseline value or <100 mmHg, or MAP <70mmHg) 20 minutes after anesthesia induction, 12 mg ephedrine in 10 ml saline was usd Intravenously<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The level of systemic vascular resistance | The outcomes above should be measured at Immediately after the injection of the drug (T1), 30s after the injection (T2), 1 min after the injection(T3), 1 min30 s after the injection(T4), 2 min after the injection(T5), 2 min30s after the injection(T6), 3 min after the injection(T7), 3 min30s after the injection( T8), 4 min after the injection(T9), 4 min30s after the injection(T10), 5 min after the injection(T11), immediately after surgery (T12), 30 min in PACU (T13) | during surgery to 30 minutes after being sent to the PACU | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The level of cardiac output | The outcomes above should be measured at Immediately after the injection of the drug (T1), 30s after the injection (T2), 1 min after the injection(T3), 1 min30 s after the injection(T4), 2 min after the injection(T5), 2 min30s after the injection(T6), 3 min after the injection(T7), 3 min30s after the injection( T8), 4 min after the injection(T9), 4 min30s after the injection(T10), 5 min after the injection(T11), immediately after surgery (T12), 30 min in PACU (T13) | during surgery to 30 minutes after being sent to the PACU | 
| The level of cardiac index | The outcomes above should be measured at Immediately after the injection of the drug (T1), 30s after the injection (T2), 1 min after the injection(T3), 1 min30 s after the injection(T4), 2 min after the injection(T5), 2 min30s after the injection(T6), 3 min after the injection(T7), 3 min30s after the injection( T8), 4 min after the injection(T9), 4 min30s after the injection(T10), 5 min after the injection(T11), immediately after surgery (T12), 30 min in PACU (T13) | during surgery to 30 minutes after being sent to the PACU | 
| The level of heart rate | The outcomes above should be measured at Immediately after the injection of the drug (T1), 30s after the injection (T2), 1 min after the injection(T3), 1 min30 s after the injection(T4), 2 min after the injection(T5), 2 min30s after the injection(T6), 3 min after the injection(T7), 3 min30s after the injection( T8), 4 min after the injection(T9), 4 min30s after the injection(T10), 5 min after the injection(T11), immediately after surgery (T12), 30 min in PACU (T13) | during surgery to 30 minutes after being sent to the PACU | 
| The level of heart rate cardiac circulation efficiency | The outcomes above should be measured at Immediately after the injection of the drug (T1), 30s after the injection (T2), 1 min after the injection(T3), 1 min30 s after the injection(T4), 2 min after the injection(T5), 2 min30s after the injection(T6), 3 min after the injection(T7), 3 min30s after the injection( T8), 4 min after the injection(T9), 4 min30s after the injection(T10), 5 min after the injection(T11), immediately after surgery (T12), 30 min in PACU (T13) | during surgery to 30 minutes after being sent to the PACU | 
| The level of maximum pressure gradient | The outcomes above should be measured at Immediately after the injection of the drug (T1), 30s after the injection (T2), 1 min after the injection(T3), 1 min30 s after the injection(T4), 2 min after the injection(T5), 2 min30s after the injection(T6), 3 min after the injection(T7), 3 min30s after the injection( T8), 4 min after the injection(T9), 4 min30s after the injection(T10), 5 min after the injection(T11), immediately after surgery (T12), 30 min in PACU (T13) | during surgery to 30 minutes after being sent to the PACU | 
| The level of mean arterial pressure | The outcomes above should be measured at Immediately after the injection of the drug (T1), 30s after the injection (T2), 1 min after the injection(T3), 1 min30 s after the injection(T4), 2 min after the injection(T5), 2 min30s after the injection(T6), 3 min after the injection(T7), 3 min30s after the injection( T8), 4 min after the injection(T9), 4 min30s after the injection(T10), 5 min after the injection(T11), immediately after surgery (T12), 30 min in PACU (T13) | during surgery to 30 minutes after being sent to the PACU | 
| The amount of infusion volume,propofol and remifentanil |  | intraoperative | 
| The occurrence of adverse events about the cardiovascular system | Yes or No | from the beginning of the surgery to 30 minutes after being sent to the PACU | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Ephedrine, Biphasic Effects, Elderly