title: Rebound intracranial hypertension in dogs after resuscitation with hypertonic solutions from hemorrhagic shock accompanied by an intracranial mass lesion.
abstract: We compared intracranial pressure (ICP) and cerebral blood flow (CBF) in dogs after inflating a subdural intracranial balloon to increase ICP to 20 mm Hg, inducing hemorrhagic shock (mean arterial pressure [MAP] of 55 mm Hg), and infusing a single bolus of fluid consisting of either 54 mL/kg of 0.8% saline (SAL), 6 mL/kg of 7.2% hypertonic saline (HS), 20% hydroxyethyl starch (HES) in 0.8% SAL, or a combination fluid (HS/HES) containing 20% HES in 7.2% saline. Twenty-six dogs were ventilated with 0.5% halothane in N2O and O2 (60:40 ratio). As ICP was maintained at 20 mm Hg, rapid hemorrhage reduced MAP to 55 mm Hg (time interval of zero [T0]) which was maintained at that level for 30 minutes (until T30). Subsequently, over a 5-minute interval (T30-T35), one of the four randomly assigned resuscitation fluids was infused. Data were collected at baseline; after subdural balloon inflation; at T0, T30, T35, and 30-minute intervals thereafter for 2 hours (T65, T95, T125, and T155). CBF and ICP were compared using repeat-measure ANOVA. Cerebral blood flow was greater at T35 in the HS and HS/HES groups than in the HES group (P = .025). In the SAL group, ICP increased significantly from T0 to T35, remaining unchanged thereafter. At T35, ICP in the HS group was significantly lower than in the SAL group (P < .05) but subsequently increased. ICP in the HS/HES group exceeded that in all other groups at T95 and T125 (P < .05). After a severe reduction in cerebral perfusion pressure (CPP), HS solutions (both HS and HS/HES) were associated with a delayed rise in ICP and did not improve global forebrain CBF in comparison with conventional saline solutions.
authors.affiliation: Department of Anesthesiology, University of Texas Medical Branch, Galveston 77555-0591, USA.
authors.forename: D S
authors.initials: DS
authors.lastname: Prough
authors.forename: J M
authors.initials: JM
authors.lastname: Whitley
authors.forename: C L
authors.initials: CL
authors.lastname: Taylor
authors.forename: D D
authors.initials: DD
authors.lastname: Deal
authors.forename: D S
authors.initials: DS
authors.lastname: DeWitt
mesh_terms: D000818:Animals; D001794:Blood Pressure; D002404:Catheterization / Q000009:adverse effects; D002560:Cerebrovascular Circulation / Q000502:physiology; D004285:Dogs; D006895:Hydroxyethyl Starch Derivatives; D006982:Hypertonic Solutions; D019586:Intracranial Hypertension / Q000209:etiology / Q000503:physiopathology*; D007427:Intracranial Pressure / Q000502:physiology; D012151:Resuscitation / Q000009:adverse effects*; D012462:Saline Solution, Hypertonic; D012771:Shock, Hemorrhagic / Q000503:physiopathology* / Q000628:therapy*; D013997:Time Factors
chemical_list: D006895:Hydroxyethyl Starch Derivatives; D006982:Hypertonic Solutions; D012462:Saline Solution, Hypertonic