Fluid Resuscitation With Isotonic or Hypertonic Saline Solution Avoids Intraneural Calcium Influx After Traumatic Brain Injury Associated With Hemorrhagic Shock

Author(s)

Balbino, Marcos ^[1] ; Capone Neto, Antonio ^[1] ; Prist, Ricardo ^[1] ; Ferreira, Alice Teixeira ^[2] ; Poli-de-Figueiredo, Luiz F. ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Med, LIM26, Dept Surg, BR-01246903 Sao Paulo - Brazil

^[2] Univ Fed Sao Paulo, Dept Byophys, Sao Paulo - Brazil

• Document type: Journal article
• Source: JOURNAL OF TRAUMA-INJURY INFECTION AND CRITICAL CARE; v. 68, n. 4, p. 859-864, APR 2010.
• Web of Science Citations: 7

Abstract

Background: Calcium is one of the triggers involved in ischemic neuronal death. Because hypotension is a strong predictor of outcome in traumatic brain injury (TBI), we tested the hypothesis that early fluid resuscitation blunts calcium influx in hemorrhagic shock associated to TBI. Methods: Fifteen ketamine-halothane anesthetized mongrel dogs (18.7 kg +/- 1.4 kg) underwent unilateral cryogenic brain injury. Blood was shed in 5 minutes to a target mean arterial pressure of 40 mm Hg to 45 mm Hg and maintained at these levels for 20 minutes (shed blood volume = 26 mL/kg +/- 7 mL/kg). Animals were then randomized into three groups: CT (controls, no fluid resuscitation), HS (7.5% NaCl, 4 mL/kg, in 5 minutes), and LR (lactate Ringer's, 33 mL/kg, in 15 minutes). Twenty minutes later, a craniotomy was performed and cerebral biopsies were obtained next to the lesion ({''}clinical penumbra{''}) and from the corresponding contralateral side ({''}lesion's mirror{''}) to determine intracellular calcium by fluorescence signals of Fura-2-loaded cells. Results: Controls remained hypotensive and in a low-flow state, whereas fluid resuscitation improved hemodynamic profile. There was a significant increase in intracellular calcium in the injured hemisphere in CT (1035 nM +/- 782 nM), compared with both HS (457 nM +/- 149 nM, p = 0.028) and LR (392 nM +/- 178 nM, p = 0.017), with no differences between HS and LR (p = 0.38). Intracellular calcium at the contralateral, uninjured hemisphere was 438 nM +/- 192 nM in CT, 510 nM +/- 196 nM in HS, and 311 nM +/- 51 nM in LR, with no significant differences between them. Conclusion: Both small volume hypertonic saline and large volume lactated Ringer's blunts calcium influx in early stages of TBI associated to hemorrhagic shock. No fluid resuscitation strategy promotes calcium influx and further neural damage. (AU)

• FAPESP's process: 04/15964-6 - Mechanisms of hypertonic saline solution associated to pentoxifylline and ethy-pyruvate in the reduction of multiple organ dysfunctions after trauma, sepsis and ischemia-reperfusion
• Grantee: Maurício Rocha e Silva
• Support Opportunities: Research Projects - Thematic Grants