Study on the Effect of Capacity Shock Intervention Under Goal-directed Hemodynamic Management on P-V Loop

Study Overview
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Brief Summary
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By observing the changes of P-V loop in capacity shock intervention Under Goal-directed Hemodynamic Management in patients undergoing total knee replacement, we investigate the effect of capacity shock on cardiac contractility and work in order to seek a more effective target plan of capacity shock for intraoperative patients.

Detailed Description
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Objective:By observing the changes of P-V loop in capacity shock intervention Under Goal-directed Hemodynamic Management in patients undergoing total knee replacement, we investigate the effect of capacity shock on cardiac contractility and work in order to seek a more effective target plan of capacity shock for intraoperative patients. Methods:20 patients with total knee replacement were enrolled in this study. Capacity shock therapy was used in Group A(n=10) and conventional strategy was used in Group B (n=10). V(t) was measured and calculated using TEE and P(t) was acquired by the analysis of patients'radial artery pressure waveform. We set five time points of parameter acquisition: after grouping (T1), the first shock completion(T2), the second shock completion (T3), 1h after shock treatment (T4), and operation completion(T5). We make up the P-V loop fitting P(t) and V(t) at each time point after the calibration of cardiac cycle.

Official Title
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Study on the Effect of Capacity Shock Intervention Under Goal-directed Hemodynamic Management on P-V Loop-based Myocardial Contraction and Work

Conditions
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Hemodynamics

Intervention / Treatment
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* Procedure: Fluid challenge strategy
* Procedure: conventional strategy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ASAI-II age 40- 70 weight 48 - 72 kg. Exclusion Criteria: Body mass index >30 or <15 kg/m2 Valve heart disease Left ventricular ejection fraction (LVEF) is less than 50% History of lung disease Preoperative arrhythmic disorder Permanent pacemaker Need for mechanical heart Support, Severe extrinsic vascular disease Valve dysfunction OED monitoring probe insertion contraindications Patients with preoperative assessments

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 70 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: Non-Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: capacity shock<br>2ml/kg succinylateol gelatin | Procedure: Fluid challenge strategy<br>* Patients received 2ml/kg of succinylateol gelatin within 10 min for fluid shock therapy after grouping, taking SVV as the management target. If SVV< 13% after shock therapy, the shock therapy was stopped and the infusion was maintained with 4ml/kg/h of crystal solution. If SVV ≥ 13% and ΔSV <10%, the individual would be excluded from the experiment. If SVV ≥ 13% but ΔSV≥10%, 2ml/kg of succinylateol gelatin was given again within 10 min for liquid shock therapy until SVV<13%, and 4ml/kg/h of crystal solution was maintained after reaching the target. If SVV≥ 13% after two shock treatments, they were excluded from the experiment. We excluded patients whose intraoperative bleeding ≥400ml and operative time ≥5 hours from the group.<br>|
| Other: routine management<br>conventional strategy | Procedure: conventional strategy<br>* 4ml/kg/h of crystal solution was maintained. We excluded patients whose intraoperative bleeding ≥400ml and operative time ≥5 hours from the group.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ees | Ees（End-systole Elasticity，mmHg/ml） | Baseline，After induction | 
| Ees | Ees（End-systole Elasticity，mmHg/ml） | Immediately after the intervention,complete of the first round of the fluid challenge | 
| Ees | Arterial elasticity is an invasively determined parameter of arterial load that is inversely related to arterial compliance | Immediately after the intervention,complete of the second round of the fluid challenge | 
| Ees | Ees（End-systole Elasticity，mmHg/ml） | 1h after the first fluid challenge | 
| Ees | Ees（End-systole Elasticity，mmHg/ml） | At the end of surgery | 
| SW | SW（Stroke Volume，mmHg·ml） | Baseline，after induction | 
| SW | SW（Stroke Volume，mmHg·ml） | Immediately after the intervention,complete of the first round of the fluid challenge | 
| SW | SW（Stroke Volume，mmHg·ml） | Immediately after the intervention,complete of the second round of the fluid challenge | 
| SW | SW（Stroke Volume，mmHg·ml） | 1h after the first fluid challenge | 
| SW | SW（Stroke Volume，mmHg·ml） | At the end of surgery | 
| Ea | Ea(Arterial elasticity, mmHg·ml) | Baseline，after induction | 
| Ea | Ea(Arterial elasticity, mmHg·ml) | Immediately after the intervention,complete of the first round of the fluid challenge | 
| Ea | Ea(Arterial elasticity, mmHg·ml) | Immediately after the intervention,complete of the second round of the fluid challenge | 
| Ea | Ea(Arterial elasticity, mmHg·ml) | 1h after the first fluid challenge | 
| Ea | Ea(Arterial elasticity, mmHg·ml) | At the end of surgery |