A Correlation Study of Internal Jugular Vein Variability Under Deep Inhalation and Propofol-induced Hypotension

• Ultrasound records at least one quiet breathing cycle and one deep inhalation cycle to calculate IJVV
• Propofol was infused target-controlled at 4 μg/ml, and changes in arterial blood pressure within 3 minutes of propofol induction were observed.
• Aim to conduct a prospective observational study to evaluate the correlation between internal jugular vein variability during deep inhalation and the decrease in blood pressure during propofol induction.

Inclusion criteria

• age over 60 years
• American Society of Anesthesiology (ASA) status Ⅱ-Ⅲ
• Surgery with radial artery puncture
• Propofol induction

Exclusion criteria

• BMI≥30kg/m2
• People with short necks;
• Previous hypotension (systolic blood pressure <90mmHg or mean arterial pressure <65mmHg)
• Previous poorly controlled hypertension
• Cardiac insufficiency , EF value<50%
• Upper limb deep vein thrombosis
• History of radiotherapy or neck surgery
• Inability to maintain a supine position for necessary measurements
• Mechanical ventilation status or inability to take deep breaths patients
• gastrointestinal surgery
• patients allergic to propofol.