Prediction Model of the Blood Pressure Response to the Administration of Fluids in Abdominal Surgery Using the Pram Method.

Study Overview
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Brief Summary
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Fluid therapy is considered a first-line therapy in resuscitation protocols for hemodynamically unstable patients. The administration of fluids usually translates into an increase in Cardiac Output. However, not all patients increase mean blood pressure after fluid administration. To determine if fluids the administration improves blood pressure, it is necessary to evaluate the dependence of preload, vasomotor tone, and left ventricular stroke volume. The aim of this study is to confirm the usefulness of dynamic elastance, cardiovascular impedance, cardiac cycle efficiency, and other hemodynamic parameters calculated with the PRAM method as predictors of blood pressure response after fluid administration in open abdominal surgery. This will allow us to make and evaluate a predictive model for the blood pressure response after fluid administration in open abdominal surgery.

Official Title
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Prediction Model of the Blood Pressure Response to the Administration of Fluids in Abdominal Surgery Using the Pram Method.

Conditions
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Open Abdominal Surgery

Intervention / Treatment
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* Procedure: Fluid administration


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients ≥ 18 years Patients scheduled for open abdominal surgery lasting ≥ 120 minutes under general anesthesia with mechanical ventilation and the use of VT of 8 ml / kg ideal weight and who require serious arterial monitoring. Exclusion Criteria: Patients <18 years. Patients> 80 years. Pregnant women. Urgent surgery. ASA >3 Pathologies that may alter the quality of the arterial signal due to alterations of the dicrotic incisura. Poor quality of the arterial pressure wave due to artifacts of the transduction system (resonance and damping). Personal history of: Cardiac arrhythmia. Left ventricular ejection fraction <30% Right ventricular dysfunction (peak systolic tricuspid annulus velocity <0.16 m / sec) Intracardiac shunt Preoperative creatinine> 1.4 mg / dl. Dialysis Previous treatment with beta-blockers

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Responders<br> | Procedure: Fluid administration<br>* Patients will be treated in accordance with the criteria of the responsible physician and the hemodynamic data obtained with the Mostcareup monitor will be recorded and used for decision-making according to the hemodynamic management protocols of each center. If the patient has a PPV ≥ 14%, for 3 minutes and a MAP <65 mm Hg or a Systolic Blood Pressure <90 mm Hg, a bolus volume load of 3 ml / kg weight of a balanced crystalloid solution in a time of 10 minutes36,37. The start of the volume charge (T1) will be noted by an event mark on the MostCareup monitor. The end of the volume charge (T2) will be noted by an event mark on the MostCareup monitor. Five minutes after the completion of the volume charge a new event will be marked on the MostCare monitor (T3). Both brands will serve as a reference for the analysis of hemodynamic data. Patients will be considered responders to the administration of fluids if the cardiac index (CI) increase.<br>|
| Non responders<br> | Procedure: Fluid administration<br>* Patients will be treated in accordance with the criteria of the responsible physician and the hemodynamic data obtained with the Mostcareup monitor will be recorded and used for decision-making according to the hemodynamic management protocols of each center. If the patient has a PPV ≥ 14%, for 3 minutes and a MAP <65 mm Hg or a Systolic Blood Pressure <90 mm Hg, a bolus volume load of 3 ml / kg weight of a balanced crystalloid solution in a time of 10 minutes36,37. The start of the volume charge (T1) will be noted by an event mark on the MostCareup monitor. The end of the volume charge (T2) will be noted by an event mark on the MostCareup monitor. Five minutes after the completion of the volume charge a new event will be marked on the MostCare monitor (T3). Both brands will serve as a reference for the analysis of hemodynamic data. Patients will be considered responders to the administration of fluids if the cardiac index (CI) increase.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Dynamic elastacy ratio PPV/SVV | PPV/SVV | During surgery |