title: Effects of different types of fluid resuscitation for hemorrhagic shock on splanchnic organ microcirculation and renal reactive oxygen species formation.
abstract: BACKGROUND
  Fluid resuscitation is an indispensable procedure in the acute management of hemorrhagic shock for restoring tissue perfusion, particularly microcirculation in splanchnic organs. Resuscitation fluids include crystalloids, hypertonic saline (HTS), and synthetic colloids, and their selection affects the recovery of microcirculatory blood flow and reactive oxygen species (ROS) formation, which is often evident in the kidney, following reperfusion. In this study, the effects of acute resuscitation with 0.9% saline (NS), 3% HTS, 4% succinylated gelatin (GEL), and 6% hydroxyethyl starch (HES) 130/0.4 were compared in a hemorrhagic shock rat model to analyze restoration of microcirculation among various splanchnic organs and the gracilis muscle and reperfusion-induced renal ROS formation.
  
  
  METHODS
  A total of 96 male Wistar rats were subjected to sham operation (sham group), hemorrhagic shock (control group), and resuscitation with NS, HTS, GEL and HES. Two hours after resuscitation, changes in the mean arterial pressure (MAP), serum lactate level and the microcirculatory blood flow among various splanchnic organs, namely the liver, kidney, and intestine (mucosa, serosal muscular layer, and Peyer's patch), and the gracilis muscle, were compared using laser speckle contrast imaging. Renal ROS formation after reperfusion was investigated using an enhanced in vivo chemiluminescence (CL) method.
  
  
  RESULTS
  Microcirculatory blood flow was less severely affected by hemorrhaging in the liver and gracilis muscle. Impairment of microcirculation in the kidney was restored in all resuscitation groups. Resuscitation in the NS group failed to restore intestinal microcirculation. Resuscitation in the HTS, GEL, and HES groups restored intestinal microcirculatory blood flow. By comparison, fluid resuscitation restored hemorrhagic shock-induced hypotension and decreased lactatemia in all resuscitation groups. Reperfusion-induced in vivo renal ROS formation was significantly higher in the GEL and HES groups than in the other groups.
  
  
  CONCLUSIONS
  Although fluid resuscitation with NS restored the MAP and decreased lactatemia following hemorrhagic shock, intestinal microcirculation was restored only by other volume expanders, namely 3% HTS, GEL, and HES. However, reperfusion-induced renal ROS formation was significantly higher when synthetic colloids were used.
authors.affiliation: Department of Anesthesiology, National Taiwan University Hospital, No 7, Chung-Shan S. Road, Taipei, Taiwan, R.O.C. b001089018@tmu.edu.tw.|Department of Life Science, National Taiwan Normal University, No. 88, Tingzhou Road, Taipei City, Taiwan, 11677, R.O.C. b001089018@tmu.edu.tw.
authors.forename: Chun-Yu
authors.initials: CY
authors.lastname: Wu
authors.affiliation: Department of Anesthesiology, National Taiwan University Hospital, No 7, Chung-Shan S. Road, Taipei, Taiwan, R.O.C. jkjchan@gmail.com.
authors.forename: Kuang-Cheng
authors.initials: KC
authors.lastname: Chan
authors.affiliation: Department of Anesthesiology, National Taiwan University Hospital, No 7, Chung-Shan S. Road, Taipei, Taiwan, R.O.C. chengyj@ntu.edu.tw.
authors.forename: Ya-Jung
authors.initials: YJ
authors.lastname: Cheng
authors.affiliation: Department of Anesthesiology, National Taiwan University Hospital, No 7, Chung-Shan S. Road, Taipei, Taiwan, R.O.C. tonyyeh@ntuh.gov.tw.
authors.forename: Yu-Chang
authors.initials: YC
authors.lastname: Yeh
authors.affiliation: Department of Life Science, National Taiwan Normal University, No. 88, Tingzhou Road, Taipei City, Taiwan, 11677, R.O.C. ctchien@ntnu.edu.tw.
authors.forename: Chiang-Ting
authors.initials: CT
authors.lastname: Chien
mesh_terms: D000818:Animals; D000077324:Crystalloid Solutions; D005440:Fluid Therapy / Q000295:instrumentation / Q000379:methods / Q000401:mortality; D006439:Hemodynamics / Q000187:drug effects; D007262:Infusions, Intravenous / Q000295:instrumentation / Q000379:methods / Q000401:mortality; D007552:Isotonic Solutions / Q000008:administration & dosage / Q000627:therapeutic use; D007668:Kidney / Q000098:blood supply / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D008833:Microcirculation / Q000187:drug effects* / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000032:analysis / Q000097:blood / Q000378:metabolism; D012151:Resuscitation / Q000379:methods*; D012462:Saline Solution, Hypertonic / Q000008:administration & dosage / Q000627:therapeutic use; D012771:Shock, Hemorrhagic / Q000188:drug therapy* / Q000401:mortality / Q000503:physiopathology; D012965:Sodium Chloride / Q000008:administration & dosage / Q000627:therapeutic use; D013152:Splanchnic Circulation / Q000187:drug effects*
chemical_list: D000077324:Crystalloid Solutions; D007552:Isotonic Solutions; D017382:Reactive Oxygen Species; D012462:Saline Solution, Hypertonic; D012965:Sodium Chloride