The aim of this work was to investigate the effects of low dose of norepinephrine in preperiod of hypotensive resuscitation in hemorrhagic shock.

Hemorrhagic shock is one of the leading causes of death following trauma. New fluid resuscitation concepts, including hypotensive, hypothermic, and delayed resuscitation for uncontrolled hemorrhagic shock, have been put forward and obtained a good effect both in clinical and laboratory parameters. The 2019 European guideline on the management of major bleeding and coagulopathy following trauma recommends the use of norepinephrine (NE) for maintaining target arterial blood pressure in patients with life-threatening hypotension. NE has potent α-adrenergic receptor activation activity, which can stimulate α-1 adrenergic receptors on peripheral vascular smooth muscles. High-dose NE may result in excessive arteriolar vasoconstriction which subsequently leads to the disorder of microcirculation and tissue hypoxia.

Inclusion Criteria:

• Age ≥ 18 years old.
• Both sexes.
• Patients with hemorrhagic shock

Exclusion Criteria:

• Patients with cardiac arrest at admission.
• Severe brain.
• Spinal injury (because of different target blood pressures).
• Death due to hemostatic failure within 6 h of admission.
• Pregnancy.

The data will be available upon a reasonable request from the corresponding author after the end of study for one year.

After the end of study for one year.

The data will be available upon a reasonable request from the corresponding author.