Hemodynamic Instability, Sepsis, Septic Shock, Shock
Conditions
Keywords
Tidal volume challenge, Pleth variability index
Brief summary
The aim of this study is to assess whether changes in the plethysmography variability index, during a tidal volume challenge, can reliably detect simultaneous changes in arterial blood pressure pulsatility, in patients hospitalized in intensive care unit. If results will be positive, this will allow the test to be performed even in the absence of an invasive arterial catheter.
Detailed description
Among patients in a state of shock one of the first treatments is volume expansion, consisting in a fast intravenous injection of crystalloid or colloid solutions in order to increase cardiac preload and consequently cardiac output. However, this augmentation of the cardiac output happens only in half of the patients.To avoid ineffective fluid administration several tests have been developed. One of these tests is called the tidal volume challenge (TVC). It consists of transiently increasing for 1 minute the volume of air inhaled with each breath, in mechanically ventilated patients, and then evaluating whether this change impacts the pulsatility of the arterial blood pressure, detected by an arterial catheter. This test seems reliable, but it requires an arterial catheter to be in place. It has been suggested in previous studies that pulsatility of blood pressure can be estimated by the pulsatility of the plethysmography signal (plethysmography variability index), obtained from the oxygen saturation signal that's measured in all intensive care patients. The advantage is that this measurement only requires a sensor placed at the end of a finger, on the earlobe or on the forehead. The aim of the study is to assess whether changes in the plethysmography variability index (PVI) during a TVC can reliably detect simultaneous changes in blood pressure pulsatility. This study will include patients hospitalized in intensive care unit, mechanically ventilated, in whom physicians have decided to perform a TVC as common practice. Changes, occurred during this test, in arterial blood pressure pulsatility and in plethysmography pulsatility index will be measured and compared. If results will show that changes in PVI during TVC are reliable for measuring blood pressure pulsatility changes during this test, this will allow the test to be used even in the absence of an arterial catheter.
Interventions
None listed
Sponsors
Bicetre Hospital
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* patients hospitalized in intensive care unit * physicians' decision to perform a tidal volume challenge * hemodynamic monitoring with a calibrated pulse contour analysis device (PICCO2) in place * monitoring of oxygen saturation with Masimo SET * mechanical ventilation with tidal volume of 6 ml/kg on ideal body weight
Exclusion criteria
* thoracic drainage * patient under judicial protection
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Reliability of PVI changes in diagnosing preload responsiveness during TVC | TVC is performed in 1 minute | The primary objective is to assess the reliability of PVI changes induced by a tidal volume challenge test in diagnosing a preload responsiveness state in adult ICU patients. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Reliability of PVI absolute values to diagnose preload responsiveness | TVC is performed in 1 minute | Secondary objective is to test the reliability of absolute values of PVI to diagnose a preload responsiveness state in adult intensive care patients. |
| Evaluation of PVI changes during TVC according to sensor position | TVC is performed in 1 minute | Third objective is to compare the value of changes in PVI induced by a tidal volume challenge test to diagnose a preload responsiveness state according to the location of the plethysmographic measurement (finger, earlobe, forehead). |
| Comparison of PPV and PVI changes during PLR test or volume expansion | PLR is performed in 1 minute | Forth objective is to compare the changes in pulse pressure variation (PPV) and PVI during a passive leg raising test (PLR) and a volume expansion, if applicable. |
Countries
France
Contacts
Primary ContactXavier Monnet, MD-PhD
Outcome results
None listed