Severe sepsis and septic shock represent major requirements for managers of health. Models of septic shock resuscitation show that tissue perfusion (TP) is altered even though the systemic hemodynamics and regional standardization. Therefore early strategy of detection and treatment with quantitative goals within the first hours decreases the mortality rate. One way to improve tissue perfusion is the increase in mean arterial pressure (MAP). Therefore we try to determine what would be the optimal levels of MAP in the management of septic shock to improve TP. Objectives: To determine which levels of mean arterial pressure are more effective in improving lactate levels and urine output six hours after the management of septic shock with norepinephrine. Methods: An observational prospective cohort study, which was considered as showing the entire population that met the inclusion criteria w...