Background: It is necessary to keep tracks of blood and fluid treatment during admission patient in intensive care unit Patient may have signs of hypovolemic but fluid administration is not always beneficial, we are in need of bedside devices and techniques which can predict fluid responsiveness effectively and safely.      The pleth variability indices (PVI) allow noninvasive assessment of fluid management.      It is based on respiratory changes in arterial pulse pressure. PVI reflect vascular tone, circulating blood volume and intra thoracic pressure. Objective: To compare between PVI and CVP (central venous pressure) as effective measures to manage of fluid loading in monitorization in I.C.U. Patients and Methods: This study was carried out at King Khaled Hospital between June 2017 and October 2018 on 200 randomized patients dividing into two equal groups: Group (I) measuring fluid by CVP, and Group (II) measuring fluid by Masimo to assess fluid management therapy. Results: In comparison of fluid management in I.C.U, the amount of fluid replacement was 3500 ± 1980.2 in group (I), and 1913 ± 540 in group (II). There was no significant difference between the two groups in red blood cells transfusion or hemoglobin level. Conclusion: Masimo can be used as bedside non-invasive technique to measure fluid responsiveness in operating room and intensive care unit without complication, and more reliable than some invasive technique in guiding fluid therapy.