Norepinephrine, Post-induction Hypotension
Conditions
Brief summary
The goal of this clinical trial is to determine the ED50 and ED95 of prophylactic norepinephrine infusion for preventing post-induction hypotension in elderly patients undergoing major abdominal surgery using up-and-down sequential method . The main question it aims to answer is: What is the effective concentration of prophylactic norepinephrine infusion for preventing post-induction hypotension in elderly patients. Participants will receive different concentrations of norepinephrine infusion at the beginning of anesthesia induction until 15 minutes after intubation.
Interventions
The treatment group will receive a continuous infusion of norepinephrine at the beginning of anesthesia induction until 15 minutes after intubation. The dosage of norepinephrine was decided by the up-and-down sequential allocation method with an initial dose of 0.05 µg/kg/min and a 0.005 µg/kg/min gradient.
Sponsors
Second Affiliated Hospital, School of Medicine, Zhejiang University
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
65 Years to 80 Years
Healthy volunteers
No
Inclusion criteria
* aged 65 to 80 years * Undergoing major abdominal surgery * American Society of Anesthesiologists (ASA) physical status of I/II/III
Exclusion criteria
* Patient refusal * Severe untreated or uncontrolled hypertension despite medications * Bradycardia (heart rate \< 50 beat per minute) * Cardiac morbidities, heart block greater than the first degree * Severe hepatic and renal dysfunction * hyperthyroidism * vascular diseases * BMI\>30 * Monoamine oxidase inhibitors were used 2 weeks before surgery
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Incidence of hypotension | 15 minutes after intubation | less than 80% baseline blood pressure less than 80% baseline blood pressure less than 80% baseline blood pressure |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| incidence of bradycardia | 15 minutes after intubation | heart rate less than 50 beat per minute |
| incidence of reactive hypertension | 15 minutes after intubation | increased mean arterial pressure by \> 20% of the baseline reading |
Countries
China
Contacts
Primary ContactMin Yan, Doctor
Outcome results
None listed