Norepinephrine Prevent Post-induction Hypotension in High-risk Patients

Study Overview
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Brief Summary
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The investigators aimed to investigate the effects of continuous infusion of norepinephrine before and after general anesthesia induction on the occurrence of post-induction hypotension.

Detailed Description
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Intraoperative hypotension is common after general anesthesia induction and is associated with adverse postoperative events. Norepinephrine is one of the most applied vasopressors in clinical to treat intraoperative hypotension. Due to the absence of effective measures for predicting intraoperative hypotension, infusing norepinephrine before and during anesthesia induction may reduce intraoperative hypotension. There is currently a lack of research regarding whether continuous norepinephrine infusion before and during the induction of general anesthesia can mitigate or prevent post-induction hypotension. The investigators aim to investigate the effects of continuous infusion of norepinephrine before and after general anesthesia induction on the occurrence of post-induction hypotension.

Official Title
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Continuous Norepinephrine Infusion Before General Anesthesia to Prevent Post-induction Hypotension in High-risk Patients Undergoing Major Noncardiac Surgery

Conditions
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Anesthesia, Blood Pressure, Norepinephrine

Intervention / Treatment
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* Drug: Norepinephrine Hydrochloride
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients aged above 65 years or those above 45 years with at least one of the following preoperative cardiovascular diseases: essential hypertension, coronary artery disease, stroke, or type I/II diabetes mellitus. Patients who will receive major noncardiac surgery as open or laparoscopic abdominal surgeries with an anticipated operative duration over two hours, including gastrointestinal, liver, pancreatic, bladder, and uterine/adnexal surgeries. Exclusion Criteria: Patients who declined to participate in the present study. Patients enrolled in another ongoing clinical study. Patients with systolic arterial pressure (SAP) below 90 mmHg or above 160 mmHg, or heart rate (HR) over 100 beats per minute (bpm) before anesthesia induction. Patients who have experienced any type of shock within 30 days before surgery. Patients with circulatory instability require continuous or intermittent positive inotropic and/or vasopressors within 24 hours before surgery. Patients receive continuous or intermittent intravenous antihypertensive agents within 24 hours before surgery. Patients underwent coronary artery bypass grafting, coronary angiography, or coronary stenting within 180 days before surgery. Patients who were diagnosed with new-onset tachyarrhythmia within 180 days before surgery, such as atrial fibrillation, atrial flutter, and premature ventricular contractions. Patients with preoperative alanine aminotransferase >80 international units and/or glomerular filtration rate < 80 ml/min within the 180 days before surgery. Patients are ineligible for intraoperative invasive radial artery blood pressure monitoring. Patients with a known history of allergy to norepinephrine. Patients who were planned for rapid sequence induction. Patients who were scheduled for awake tracheal intubation. Patients who were scheduled for double-lumen endotracheal intubation. Pregnant or lactating patients.

Ages Eligible for Study
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Minimum Age: 45 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Norepinephrine<br>The interventional group will receive a continuous infusion of norepinephrine 5 minutes (0.01μg/kg*min) before anesthesia induction until skin incision. | Drug: Norepinephrine Hydrochloride<br>* Both arms of patients will receive standard anesthesia and surgical management. Radial artery cannulation and invasive blood pressure monitoring will be perform. Norepinephrine will be pumped at a rate of 10 ml/h for 5 minutes before anesthesia induction to skin incision.<br>|
| Placebo Comparator: Placebo<br>the placebo group will receive a continuous infusion of normal saline (10 ml/h) 5 minutes before anesthesia induction until skin incision. | Drug: Placebo<br>* Normal saline will be pumped at a rate of 10 ml/h for 5 minutes before anesthesia induction to skin incision.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of post-induction hypotension | Hypotension: mean arterial pressure (MAP) <65 mmHg | From induction of general anesthesia to skin incision (up to one hour from induction of general anesthesia) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of the following abnormal vital signs | MAP<65 mmHg, MAP<55 mmHg, MAP decreased over 20% ,30% and 40% from preoperative level; MAP increased over 20%, 30%, and 40% from preoperative level; SAP < 90 mmHg; Systolic arterial pressure (SAP) > 160 mmHg; Heart rate (HR) < 40 bpm, HR > 100 bpm; dosage of norepinephrine given by anesthesiologists; amount of fluid; the time-point of the first events of MAP < 65 mmHg, MAP < 55 mmHg, SAP < 90 mmHg, SAP > 160 mmHg, MAP increased over 20%, 30%, and 40% from preoperative level. | From induction of general anesthesia to skin incision (up to one hours from induction of general anesthesia) | 
| Incidence of the following abnormal vital signs | MAP<65 mmHg, MAP<55 mmHg, MAP decreased over 20%, 30%, and 40% from preoperative level; MAP increased over 20%, 30%, and 40% from preoperative level; SAP < 90 mmHg; SAP > 160 mmHg; HR < 40 bpm, HR > 100 bpm. Dosage of norepinephrine given by anesthesiologists; amount of fluid; the time-point of the first events of MAP < 65 mmHg, MAP < 55 mmHg, SAP < 90 mmHg, SAP > 160 mmHg, MAP increased over 20%, 30%, and 40% from preoperative level | From surgical incision to the end of surgery (up to six hours from surgical incision) | 
| Incidence of the following abnormal vital signs | MAP<65 mmHg, MAP<55 mmHg, MAP decreased over 20%, 30%, and 40% from preoperative level; MAP increased over 20%, 30%, and 40% from preoperative level; SAP < 90 mmHg; SAP > 160 mmHg; HR < 40 bpm, HR > 100 bpm. Dosage of norepinephrine given by anesthesiologists; amount of fluid; the time-point of the first events of MAP < 65 mmHg, MAP < 55 mmHg, SAP < 90 mmHg, SAP > 160 mmHg, MAP increased over 20%, 30%, and 40% from preoperative level | from the end of surgery until leaving the post-anesthesia care unit (up to four hours from the end of surgery) | 
| Postoperative major adverse cardiac events | Cardiac death, myocardial infarction, on-fatal cardiac arrest, coronary revascularization | Within 30 days after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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intraoperative hypotension, arterial pressure, general surgery, general anesthesia, noncardiac surgery