The aim of this clinical trial study is to determine of the effect of passive movement of lower extremity on hemodynamic and ventilation parameters in patients under ventilator in intensive care unit. 64 patients under ventilator with lack of deep vein thrombosis, fracture or amputation of lower limbs; and spine injury who admitted to the intensive care unit, will select through convenience sampling and assignee to the intervention group and control group(with equal numbers) using block random allocation. At baseline, hemodynamic parameters such as systolic blood pressure, diastolic blood pressure, mean arterial pressure, arterial oxygen saturation, pulse rate, pulse pressure and temperature, and ventilation parameters such as respiratory rate, respiratory tidal volume, and respiratory minute volume of all samples will be record. While the control group will receive the routine treatment and cares, in the intervention group, in addition to routine treatment and cares, the nurses will do, protocol passive movement of the lower extremity consist of each leg rising, high and down and rotational movements on the ankles, bend and straighten of the knee, flexion and extension of hip joints for patients who are at semi setting in angle of 30 degrees during 22 minutes. Above hemodynamic and ventilation parameters will record Immediately, 2 hour, 6 hour,12 hour, and one day after passive movement of lower extremity in each study group, and data will analyze and compare.