C5-Blocking Antibody Reduces Fluid Requirements And Improves Responsiveness To Fluid Infusion In Hemorrhagic Shock Managed With Hypotensive Resuscitation

C5-blocking antibody reduces fluid requirements and improves responsiveness to fluid infusion in hemorrhagic shock managed with hypotensive resuscitation. J Appl Physiol 102: 673-680, 2007. First published October 26, 2006; doi:10.1152/japplphysiol.00917.2006.-Hypotensive resuscitation strategies and inhibition of complement may both be of benefit in hemorrhagic shock. We asked if C5-blocking antibody (anti-C5) could diminish the amount of fluid required and improve responsiveness to resuscitation from hemorrhage. Awake, male Sprague-Dawley rats underwent controlled hemorrhage followed by prolonged (3 h) hypotensive resuscitation with lactated Ringer's or Hextend, with or without anti-C5. Anti-C5 treatment led to an estimated 62.3 and 58.5% reduction in the volume of Hextend and lactated Ringer's, respectively. In the subgroup of animals with a positive mean arterial pressure (MAP) response to fluid infusion following prolonged hypotension, anti-C5 treatment led to an estimated 4.7- and 4.1-fold increase in mean arterial pressure response per unit Hextend and lactated Ringer's infused, respectively. We observed no significant postresuscitation metabolic differences between the anti-C5 groups and controls. Whether anti-C5 could serve as a volume-sparing adjunct that improves responsiveness to fluid administration in humans deserves further study.