IRCT20101211005363N13 IRCT 2019-06-13 Zanjan University of Medical Sciences The effect of positive end expiratory pressure on internal jugular vein collapsibility index Evaluation of the effect of positive end expiratory pressure on internal jugular vein collapsibility index in mechanically ventilated patients in intensive care unit. 2019-05-10 anticipated 30 Complete https://irct.ir/trial/38877 interventional Randomization: N/A, Blinding: Double blinded, Placebo: Not used, Assignment: Single, Purpose: Diagnostic, Blinding description: In this study, patients are not aware of the treatment group due to the decreased level of consciousness. The researcher who studies the variables, does not know the intervention and change of ventilator setting is done by another person. N/A Evaluation of internal jugular vein collapsibility index in three different of positive end expiratory pressure. Intervention group: The patients will be placed on the ventilator under the following conditions. SIMV: TV= 8 cc/Kg, RR=10, PEEP=0, Fio2=50%. Then positive end expiratory pressure of ventilator will be changed to 5 and 10 cm H2O and the internal jugular colapsibility index will be measured after each conditions.. Undecided - It is not yet known if there will be a plan to make this available Justification or reason for indecision in sharing IPD is No more information