Clinical Trials Logo

Clinical Trial Summary

Fluid evaluation is relevant in critical care. Cardiac ultrasound is the first line of evaluation in hemodynamic characterization of patients in shock, to tailor therapy. Fluid responsiveness predictors allow to better decide when to administer fluids, and transesophagic view of superior vena cava is an effective one. Recently a transthoracic view of the superior vena cava has been described. The investigators aim to evaluate if the variations of superior vena cava can predict fluid responsiveness in critically il, ventilated patients. Hypothesis: Respiratory variations of superior vena cava diameter, evaluated with transthoracic ultrasound, can predict fluid responsiveness

Clinical Trial Description

Prospective evaluation of diameter variability of the superior vena cava by transthoracic echocardiography as fluid responsiveness predictor in critically ill patients: Background Fluid administration is frequent in critically ill patients, particularly during reanimation and its empirical use is recommended as an initial step during this phase [1]. However, even though excess fluid administration is associated to negative outcomes [2-4] fluid use is still being empirical and with scarce application of responsiveness predictors before its indication [5]. Different measurements or maneuvers exist, that allow clinicians to predict if a patient would present a positive fluid response, usually defined as cardiac output increasing 15% when infusing 500ml of crystalloids, and application of these predictive parameters could have clinical benefits on outcomes by avoiding inappropriate fluid administration [6-8]. As for the variables used, different types stand out. In general, flow or pressure variations originated in cardiothoracic interaction, auto-infusion and reduced fluid test evaluations such as the "mini" o "micro" fluid tests, in addition venous diameter variations in ultrasound evaluation with variable accuracy depending on the context [7, 9-15]. However, cardiothoracic interaction variables might have false positive results when right ventricular failure is present, given the cyclic increment on its afterload induced by positive pressure ventilation, reducing right ventricle stroke volume [7, 16-18 ] limiting its application in established or unknown and probable right heart failure if and advanced hemodynamic monitoring has not been performed to rule it out. In this context, venous evaluations and reduced volume fluid test have advantages, and particularly in patients in shock under positive pressure ventilation, superior vena cava variation, being a better predictor than inferior vena cava [10]. However, traditionally, superior vena cava can only be observed with transesophageal echocardiography and that can be a limitation in resource limited settings. Recently a new transthoracic acoustic window has been described, using a vertical left parasternal approach [19] that allows evaluation of the superior vena cave, and initially, this approach shows a good correlation with the transesophageal measurement, and acceptable feasibility in the pilot study patients. In this way, it can be postulated as possible, to evaluate if the variability of superior vena cava diameter on a transthoracic approach can be used as a fluid responsiveness predictor in critically ill patients on positive pressure ventilation. Hypothesis Superior vena cava diameter respiratory variation evaluated with transthoracic ultrasound can predict fluid responsiveness in critically ill patients in positive pressure ventilation. Objective To evaluate if superior vena cava respiratory diameter variation is associated with fluid responsiveness, when compared with the mini fluid infusion of 100ml evaluated with expiratory left ventricle outflow tract velocity time integral (LVOT-VTI) before and after fluid administration. [14, 20, 21] Methods After evaluation, inclusion and exclusion criteria checking: A basal echocardiography is performed, main pattern and clinical data are recorded (age, sex, weight, height, main diagnosis, secondary diagnosis, length of stay, surgical procedures, sequential organ failure assesment (SOFA) score, renal replacement therapy), respiratory (ventilator mode, tidal volume, respiratory rate, positive end expiratory pressure (PEEP), plateau pressure, peak inspiratory pressure, autoPEEP, fraction of inspired oxygen (FiO2), I:E relation, total inspiratory time), hemodynamic data from unit monitors. (cardiac rate, systolic pressure, diastolic pressure, mean pressure, central venous pressure) and closest laboratory to evaluation (lactate, venous oxygen saturation (ScVO2), arterial partial pressure of oxygen (PaO2), arterial partial pressure of carbon dioxide (PaCO2), pH, base excess (BE), bicarbonate (HCO3), carbon dioxide (CO2) arterio-venous difference, ) - Superior vena cava evaluation, Respiratory variation observed in M mode and measured. Registry of expiratory and inspiratory diameter (evaluated in the same cardiac cycle phase) - Using Apical 5 chamber view, basal LVOT-VTI would be obtained, 3 measurements in regular rhythms and 5 measurements in irregular rhythms such as atrial fibrillation. 100 ml will be infused without changing the view and end-expiratory LVOT-VTI would be obtained a minute after infusion in the same fashion as before. - Considering ultrasound evaluation is part of standard patient care, informed consent was waived by the ethical board. - For analysis, the proportion of variation in superior vena cava (SVC) and VTI variation would be calculated as percentage. - All values will be registered in a google drive table and then included in microsoft excel for coding and analyzed with Stata 12. - Fluid responsiveness will be defined as 10% increase in VTI with the "mini bolus" fluid test, considering the minimal detectable change [14, 21]. - For analysis, receiver operator curve (ROC) statistic will be done in Stata 12. - Summary variables of the population will be presented. - For diagnostic evaluation, the tool "roctab" for receiver operating characteristic curve will be used, obtaining cut off values, sensitivity, specificity and gray area in addition to traditional area under curve (AUC). A dichotomic value for simple orientation will be selected with an ideally balanced sensitivity and specificity for general use. Linear correlation will be explored to detect a continuous relation between SVC variation and VTI increase. - Window success will be recorded and proportion will be analysed during the months of the study to check for performance improvements that might be expected as a learning curve effect. - Additional data might allow post hoc analysis including window feasibility in association with clinical variables and - After the ultrasound evaluation, the result of the 100ml test will be informed to the treating physician. - Sample size: Considering a possible 50% loss with inadequate acoustic window, 100 evaluated patients would achieve at least 48 included to obtain AUC 0.7. (estimating 24 to be responders and 24 not responders) ;

Study Design

Related Conditions & MeSH terms

NCT number NCT05211765
Study type Observational
Source University of Chile
Contact Diego Ugalde, MD
Phone +56974197896
Email [email protected]
Status Recruiting
Start date March 7, 2021
Completion date December 2022

See also
  Status Clinical Trial Phase
Recruiting NCT05066256 - LV Diastolic Function vs IVC Diameter Variation as Predictor of Fluid Responsiveness in Shock N/A
Terminated NCT02755155 - Optimization of Therapeutic Human Serum Albumin Infusion in Selected Critically Ill Patients Phase 4
Not yet recruiting NCT01941472 - Transcutaneous pO2, Transcutaneous pCO2 and Central Venous pO2 Variations to Predict Fluid Responsiveness N/A
Terminated NCT01696175 - PICU Admission Lactate and Central Venous Oxymetry Study N/A
Completed NCT01680783 - Non-Invasive Ventilation Via a Helmet Device for Patients Respiratory Failure N/A
Recruiting NCT01174966 - Assessment of Transcutaneous Oxygen Tension/Oxygen Challenge Test in Intensive Care Unit (ICU) Patients N/A
Recruiting NCT01157299 - Hemodynamic Evaluation of Preload Responsiveness in Children by Using PiCCO N/A
Completed NCT00743522 - Programming Implantable Cardioverter Defibrillators in Patients With Primary Prevention Indication
Completed NCT03296891 - Point of Care Ultrasonography In The Management of Shock: A Pilot Study N/A
Recruiting NCT05330676 - Evaluation of Microcirculatory Function and Mitochondrial Respiration After Cardiovascular Surgery
Recruiting NCT04615065 - Acutelines: a Large Data-/Biobank of Acute and Emergency Medicine
Active, not recruiting NCT04079829 - Postoperative Respiratory Abnormalities
Completed NCT04089098 - VOLume and Vasopressor Therapy in Patients With Hemodynamic instAbility
Completed NCT03190408 - Variation in Fluids Administered in Shock
Not yet recruiting NCT05092165 - Methylene Blue for the Prevention of Hypotension During Hemodialysis Phase 2
Completed NCT05193123 - Psychological Trauma and Resilience After Critical Illness
Recruiting NCT02876406 - ΔvapCO2 / Cav02 Ratio as a Prognostic Marker and Predictor of Complications After Cardiac Surgery N/A
Active, not recruiting NCT02867943 - GapCO2 and Respiratory Rate in Patients Under Volume Mechanical Ventilation N/A
Completed NCT02652364 - Strong Ion Gap as Prognostic Indicator for Adult Patients Admitted With Shock to the Intensive Care Units
Completed NCT02141607 - Evolution of Molecular Biomarkers in Acute Heart Failure Induced by Shock