Comparison of the Effects of Trendelenburg Position and Passive Leg Lift on Hemodynamics in Abdominal Surgery Patients

Study Overview
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Brief Summary
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How to maintain the stability of circulation during anesthesia has always been a concern of clinicians, including shorting the preoperative fasting time under the condition of full preoperative preparation, and giving appropriate amount of nutrient solution in combination with the patient's situation 2 4 h before surgery to reduce the blood volume insufficiency of patients before general anesthesia induction, vasoactive drugs, etc. Among them, passive leg lifting experiment is widely recognized in the world. Although passive leg lifting has many advantages, it still has some limitations in the operation process. This study tried to find the corresponding head low and foot high Angle corresponding to the same hemodynamic changes caused by passive leg lifting.

Detailed Description
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For low head and high feet, studies have shown that 20° can reduce the incidence of hypotension during the induction period of general anesthesia in patients undergoing gastrectomy and has therapeutic effect on it, as well as reduce the use of vasoactive drugs during the induction period of general anesthesia. There were no perioperative complications. The passive leg lift test can be repeated and does not overload the patient with fluid. However, there is no relevant research on the relationship between the two, which is exactly the innovation of this topic.

Official Title
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Comparison of the Effects of Trendelenburg Position and Passive Leg Lift on Hemodynamics in Abdominal Surgery Patients

Conditions
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The Angle of Trendelenburg

Intervention / Treatment
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* Other: Trendeleburg -5 degree,-10 degree,-15 degree


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18 75 years old Good image of TTE can be obtained Sedative mechanical ventilation （Vt 8～10ml/kg） Circulation was relatively stable before the experiment began There is no contraindication to rehydration Exclusion Criteria: TTE acquisition is not ideal Patients did not agree to participate in the experiment Diseases of the central nervous system，patients with increased intracranial pressure Arrhythmia patients; Patients with increased intra-abdominal pressure; Bedridden patients; Patients with venous thrombosis of lower limbs; Patients with venous foreign body of lower limbs; Patients with circulatory instability; Patients with obstructive shock; Patients with moderate or above heart valve reflux

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Trendeleburg -5 degree group,-10 degree group,-15 degree group<br>Norepinephrine was continuously pumped at 0.5ug/kg/min | Other: Trendeleburg -5 degree,-10 degree,-15 degree<br>* Use a -5 or -10 or -15 degree trendelenburg position<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PPV(pulse pressure variation) | Change from PPV at T1to T6 | T1:A supine position with a 10° upward bed angulation；T2: After passive leg lift；T3：The same position with T1；T4:After trendelenburg position；T5:The same position with T1;T6:After fluid infusion | 
| VTI(velocity time integral) | Change from VTI at T1 to T6 | T1:A supine position with a 10° upward bed angulation；T2: After passive leg lift；T3：The same position with T1；T4:After trendelenburg position；T5:The same position with T1;T6:After fluid infusion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| SBP(Systolic Blood Pressure) | The variation tendency of T1 to T6 | T1:A supine position with a 10° upward bed angulation；T2: After passive leg lift；T3：The same position with T1；T4:After trendelenburg position；T5:The same position with T1;T6:After fluid infusion | 
| MAP(Mean Artery Pressure) | The variation tendency of T1 to T6 | T1:A supine position with a 10° upward bed angulation；T2: After passive leg lift；T3：The same position with T1；T4:After trendelenburg position；T5:The same position with T1;T6:After fluid infusion | 
| HR HR(Heart Rate) | The variation tendency of T1 to T6 | T1:A supine position with a 10° upward bed angulation；T2: After passive leg lift；T3：The same position with T1；T4:After trendelenburg position；T5:The same position with T1;T6:After fluid infusion |