Moderate Ringer's Lactate Solution Resuscitation Yields Best Neurological Outcome in Controlled Hemorrhagic Shock Combined With Brain Injury in Rats

Abstract

Anesthetized rats were assigned to sham; brain injury (BI); controlled hemorrhagic shock (CHS); BI combined with CHS (combined injury [CI]); and CI groups resuscitated with 2.5 mL/kg Ringer's lactate solution (RL-2.5), 10 mL/kg RL (RL-10), or 40 mL/kg RL (RL-40). Brain injury was induced by applying 400 millibar negative pressure for 10 s through a hollow screw inserted into a 4.5-mm burr hole drilled into the left parietal region of the skull. Five minutes after BI, 30% of circulating blood volume was withdrawn for 10 min to induce CHS. One hour of fluid resuscitation commenced 20 min posthemorrhage. MAP, lactate, and base excess levels were significantly improved in the RL-40 group compared with all other hemorrhaged groups. The hematocrit level 1 h after resuscitation began was significantly lower in the RL-40 group (27.6% +/- 0.57%) than in all other groups. The RL-40 group had the worst neurological severity score 24 h postsurgery. MAP, lactate, and base excess levels were not significantly improved in the RL-2.5 group, however, the number of surviving neuronal cells in the perilesional brain region was significantly higher than in the CI or RL-40 groups. MAP, lactate, and base excess levels were significantly improved in the RL-10 group (P < 0.05). Mobility and the number of surviving neurons in the perilesional region of the brain were significantly better in the RL-10 group than in the CI or RL-40 groups (P < 0.05). Although massive fluid resuscitation yields preferable hemodynamic and metabolic outcomes, neurological outcomes are better after moderate fluid resuscitation for BI combined with controlled hemorrhagic shock.

Volume replacement with Ringer-lactate is detrimental in severe hemorrhagic shock but protective in moderate hemorrhagic shock: studies in a rat model

“…Hartmann first added lactate to RS to compensate for metabolic acidosis [24]. The alkalization that accompanies lactate metabolism was later confirmed by several other research groups [9,10,25,26]. In direct contrast, a recently published paper [16] and the present experiments report that neither an alkalizing effect of lactate infusion, that is, an improvement of metabolic acidosis, nor an improvement of organ injury or survival was observed in resuscitation with RL compared to resuscitation with RS in severe hemorrhagic shock.…”

Whole blood and hypertonic saline resuscitation improve the outcomes of controlled hemorrhagic shock combined with penetrating brain injury in rat

“…At the end of the surgical procedure, the tubing was removed, and the femoral arteries and vein were ligated. BI was induced using the “dynamic cortical deformation” model, as previously described [24, 25]. Briefly, after scalp insicion, 5 mm diameter burr hole was drilled in the left parietal region, the dura was removed and negative pressure of 300 torr (40kPa) was applied to the cortical surface for 10 sec.…”

“…Twenty four and 48 hours after surgery, neurological state of the rat was assessed by the neurological severity score (NSS) grading system, as previously described [25]. Points were assigned for alteration of motor function and behavior so that a maximal score of 25 represents severe neurological dysfunction whilst a score of 0 indicates an intact neurological condition (opposite to the human Glasgow Coma Scale).…”

“…Transcardial perfusion with 120ml of heparinized saline followed by 120 ml of 4% formaldehyde was conducted, as previously described [25]. The brain and a section of the right lung lobe were removed, fixated with 4% formaldehyde, and embedded in paraffin, for histological examination.…”

Hemorrhagic shock: The "physiology approach"

“…systolic of ≥100 mmHg particularly in view of the fact that the brain loses its circulation self-regulatory capacity at variable levels of HI. [6970]…”