Rapid Warfarin reversal in the setting of intracranial hemorrhage: a comparison of plasma, recombinant activated factor VII, and prothrombin complex concentrate.

OBJECTIVE: To compare the safety and effectiveness of three methods of reversing coagulopathic effects of warfarin in patients with potentially life-threatening intracranial hemorrhage. METHODS: A retrospective electronic medical record review of 63 patients with warfarin-related intracranial hemorrhage between 2007 and 2010 in an integrated health care delivery system was conducted. The three methods of rapid warfarin reversal were fresh-frozen plasma (FFP), activated factor VII (FVIIa; NovoSevenRT [Novo Nordisk, Bagsværd, Denmark]), and prothrombin complex concentrate (PCC; BebulinVH [Baxter, Westlake Village, California, USA], ProfilnineSD [Grifols, North Carolina, USA]), each used adjunctively with vitamin K (Vit K, phytonadione). We determined times from reversal agent order to laboratory evidence of warfarin reversal (international normalized ratio [INR]) in the first 48 hours and compared INR rebound rates and complications in the first 48 hours. RESULTS: Reversal with FFP took more than twice as long compared with FVIIa or PCC. To reach an INR of 1.3, mean (±SD) reversal times were 1933 ± 905 minutes for FFP, 784 ± 926 minutes for FVIIa, and 980 ± 1021 minutes for PCC (P < 0.001; P < 0.01 between FFP and FVIIa, P < 0.05 between FFP and PCC). INR rebound occurred in 0 of 31 patients for FFP, 4 of 8 for FVIIa, and 0 of 7 for PCC (P = 0.001). Complications were uncommon. FVIIa was 15 and 3.5 times as expensive as FFP and PCC, respectively. CONCLUSION: As an adjunct to Vit K for rapid warfarin reversal, FVIIa and PCC appear more effective than FFP. Either FVIIa or PCC are reasonable options for reversal, but FVIIa is considerably more expensive and may have greater risk of INR rebound.

Performance characteristics of a sliding-scale hypertonic saline infusion protocol for the treatment of acute neurologic hyponatremia.

BACKGROUND AND PURPOSE: Hypertonic saline (3% NaCl) infusions can be used to treat acute neurologic hyponatremia (ANH) in critically ill patients with neurological and neurosurgical disorders such as subarachnoid hemorrhage. Adjustments in the rate of hypertonic saline infusions to treat ANH are needed to achieve a goal sodium range and are usually made on an empiric basis. To date, no data are available to determine how reliably such adjustments achieve stable, normal serum sodium concentrations or how often iatrogenic hypernatremia occurs during the course of treatment with hypertonic saline. METHODS: We have instituted a standardized sliding-scale hypertonic saline protocol to minimize patient-to-patient variability of hypertonic saline administration and to attempt to achieve safe rates of sodium correction and stable maintenance of serum sodium concentration with minimal overshoot. Here, we present a retrospective analysis of the performance characteristics of our standardized hypertonic saline protocol over a 1-year period, in 49 patients. RESULTS: The mean rate of initial sodium correction was 0.44 +/- 0.36 (mEq/l)/h. During the maintenance infusion phase, 84.3 +/- 17.8% of the time was spent in goal range (Na 136-145 mEq/l), 14.9 +/- 18.1% of the time was spent in mild undershoot (Na 130-135 mEq/l), and 0.7 +/- 3.1% of the time was spent in overshoot (Na >145 mEq/l). No adverse events attributable to infusion of hypertonic saline were encountered. CONCLUSION: Our hypertonic saline sliding-scale protocol for treatment of ANH can be used reliably and achieves normal sodium concentrations in a safe manner with minimal overshoot.

Mechanisms of increased immunogenicity for DNA-based vaccines adsorbed onto cationic microparticles.

Investigation into the mechanism of action of vaccine adjuvants provides opportunities to define basic immune principles underlying the induction of strong immune responses and insights useful for the rational development of subunit vaccines. A novel HIV vaccine composed of plasmid DNA-encoding p55 gag formulated with poly-lactide-co-glycolide microparticles (PLG) and cetyl trimethyl ammonium bromide (CTAB) elicits both serum antibody titers and cytotoxic lymphocyte activity in mice at doses two orders of magnitude lower than those required for comparable response to plasmid DNA in saline. Using this model, we demonstrated the increase in potency requires the DNA to be complexed to the PLG-CTAB microparticles. Furthermore, the PLG-CTAB-DNA formulation increased the persistence of DNA at the injection site, recruited mononuclear phagocytes to the site of injection, and activated a population of antigen presenting cells. Intramuscular immunization with the PLG-CTAB-DNA complex induced antigen expression at both the injection site and the draining lymph node. These findings demonstrate that the PLG-CTAB-DNA formulation exhibits multiple mechanisms of immunopotentiation.