Dynamic Preload Indicators in Sitting Position

Study Overview
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Brief Summary
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Intraoperative optimization of cardiac output using goal directed fluid challenge is associated with better outcome. Dynamic preload dependence indicators are well validated during surgery in supine position. Positioning from supine to sitting position under anesthesia is responsible of several hemodynamic changes. Predictability and cut-off values of dynamic preload dependence indicators during surgery in sitting position are unknown. The objective of this prospective study is to evaluate ability of three dynamic preload dependence indicators, i.e. PPV (Pulse Pressure Variation), SVV (Stroke Volume Variation) and PVI (Plethysmographic Variability Index), during neurosurgery in sitting position.

Detailed Description
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The primary objective is to determine PPV, SVV and PVI thresholds for which patients respond to fluid challenge in sitting position. The secondary objectives are to determine variations of PPV, SVV and PVI measures before and after positioning in sitting position, and to compare these values to each other.

Official Title
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Abilities of Dynamic Preload Dependence Indicators to Predict Fluid Responsiveness During Neurosurgery in Sitting Position

Conditions
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Neurosurgery in Sitting Position

Intervention / Treatment
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* Procedure: Sitting position (neurosurgery)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: neurosurgery in sitting position age > 18 Exclusion Criteria: arrhythmias severe heart failure severe lung disease contraindications to esophageal Doppler monitoring probe insertion (i.e. esophageal weakness) renal failure

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: sitting position<br> | Procedure: Sitting position (neurosurgery)<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PPV (Pulse pressure variation) | PPV is derived from arterial pressure waveforms and is displayed in real -time on Intellivue MP70 Philips monitors. Value will be recorded before fluid challenge. Responders will be assessed by esophageal Doppler. | 3 minutes before and after fluid challenge in sitting position | 
| SVV (Stroke volume variation) | SVV is derived from arterial pressure waveforms and is displayed in real -time on Vigileo Edwards Lifesciences monitors. Value will be recorded before fluid challenge. Responders will be assessed by esophageal Doppler. | 3 minutes before and after positioning in sitting position | 
| PVI (Plethysmographic variability index) | PVI is derived from plethysmography waveforms and is displayed in real-time on Radical 7 Masimo monitors. Value of each indicator will be recorded before fluid challenge. Responders will be assessed by esophageal Doppler. | 3 minutes before and after positioning in sitting position | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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PPV, sitting position, SVV, PVI, fluid challenge, preload indicators