Teaching topics from the New England Journal of Medicine - Vol. 358, No. 2, January 10, 2008
The optimal systolic blood pressure in patients with uncontrolled hemorrhage is not known. Normal blood pressures may theoretically disrupt recently formed thrombi at the site of bleeding and drive additional hemorrhage. Some animal models suggest a survival benefit with permissive hypotension, defined as delayed resuscitation, leading to lower blood pressure, during uncontrolled hemorrhage. Data on clinical outcomes are mixed, with one study after penetrating trauma showing a benefit and another after penetrating and blunt trauma showing no benefit with prolonged permissive hypotension. Some clinicians used a target of 90 mm Hg for systolic blood pressure.