End-expiratory Occlusion Test and Prediction of Preload Dependence

The patients included were in the supine position in a prone position at 30°. They had continuous monitoring by: electrocardioscopy; pulse oximetry and invasive blood pressure. Diuresis was monitored hourly.

A venous access to the superior vena cava territory (central venous catheter) was set up.

The patients were sedated with a Ramsay score > 4 and ventilated in controlled assisted mode.

The sub-aortic TVI (in cm) was measured in an apical 5-chamber section by pulsed Doppler using a 1-5 MHz ultrasound probe (M-Turbo sonosite). Three sets of measurements of hemodynamic parameters and sub-aortic VTI were performed: before and at the end of 15 seconds end-expiratory occlusion and after 250 mL saline administration over 10 minutes. At each point, the investigators noted the hemodynamic, ultrasound and biological parameters.

• End-expiratory occlusion test (Diagnostic test): 15 seconds end-expiratory occlusion

Primary outcomes

• an increase in sub-aortic VTI of more than 10% [before and 10 minutes after 250 mL saline administration]: the variation of sub aortic VTI by cardiac ultrasonography

Sex: All, ages: 18 Years to any

Inclusion Criteria:

* Patients under mechanical ventilation and sedation in the intensive care units
* patients for whom the decision of 250 mL saline administration was taken for : hypotension (systolic pression under 90 mmHg or diatolic pression under 40 mmHg or tachycardia more than 90 pulse per minute or oliguria or the increase in cathecholamin needs.

Exclusion Criteria:

* Pulmonary Edema
* arrythmia
* dialysis
* Prone position

• Mhamed Sami MS Mebazaa, Pr, Principal investigator, Mongi Slim Hospital