Treatment of severe hyponatremia with continuous renal replacement therapy: A case and review of corrective strategies.

Treatment of severely hyponatremic patients with continuous renal replacement therapy (CRRT) presents a unique challenge given the lack of commercial options for hypotonic replacement solutions or dialysate. We report the case of a 55-year-old male who presented with profound, symptomatic hyponatremia in the setting of acute kidney injury (AKI). The patient was found to have a serum sodium concentration of 97 mEq/L because of free water retention that occurred during severe AKI from viral gastroenteritis and rhabdomyolysis. Continuous veno-venous hemofiltration (CVVH) was required for AKI complicated by hyperkalemia, metabolic acidosis, and uremia. To prevent overcorrection of serum sodium, replacement fluids customized to natremic status had to be prepared. Conventional replacement fluid was modified on a daily basis to create hypotonic solutions with successively higher sodium concentrations. Over the course of a week, serum sodium successfully improved in a controlled and safe fashion. This case incorporates and reviews the variety of methods that have been used to safely manage severe hyponatremia with CRRT.

A retrospective observational study of a low fixed-dose rasburicase protocol for the treatment of tumor lysis syndrome in adults.

INTRODUCTION: Tumor lysis syndrome is an oncologic emergency characterized by hyperuricemia. Previous studies have demonstrated that a fixed-dose strategy of rasburicase is as effective as the FDA approved weight-based dose. Albany Medical Center employs rasburicase 1.5 mg in patients with a uric acid (UA) between 8 and 12 mg/dL and 3 mg for UA above12 mg/dL.We aimed to evaluate the UA lowering effectiveness and provider adherence to the institutional protocol, as well as the cost-efficiency of this dosing strategy. METHODS: This is a single center, retrospective, cohort study. The electronic medical record was used to identify patients receiving rasburicase and to collect baseline demographic and laboratory data. The fixed-dose strategies of rasburicase 1.5 mg and 3 mg were compared in their degree of UA reduction and clinical outcomes. Cost-savings of fixed-dosing was compared to the FDA-approved weight-based dose. RESULTS: Mean UA reduction in the 1.5 mg group (n = 49) from baseline to 24 hours was 2.88 ± 0.88 mg/dL (p < 0.0001) and 4.83 ± 1.39 mg/dL (p < 0.0001) in the 3 mg group (n = 105). A subgroup analysis of patients who received per protocol initial doses of rasburicase showed a mean reduction in UA from baseline to 24 hours of 2.83 ± 0.62 mg/dL in the 1.5 mg group (n = 42) and 6.12 ± 1.87 mg/dL in the 3 mg group (n = 42). Using a low fixed-dose approach resulted in a cost-savings of $138,077.30 annually. CONCLUSION: Low fixed-dose rasburicase was an effective treatment, with a dose of 1.5 mg being sufficient to reach a goal UA of less than 8 mg/dL for serum UA levels below 12 mg/dL, while a 3 mg dose is appropriate for levels above 12 mg/dL. Cost analysis indicates this strategy is more cost-efficient than the FDA-approved weight-based dose.

Citrate versus heparin for apheresis catheter locks: an efficacy analysis.

INTRODUCTION: There is a paucity of medical literature regarding the efficacy of lock solutions in preventing catheter thrombosis. Traditionally, heparin has been used as the anticoagulant of choice for catheter locking, but it has many adverse effects associated with its use. Sodium citrate 4% is an attractive alternative to heparin. METHODS: Our plasmapheresis unit converted to locking all central venous catheters with sodium citrate 4% in place of heparin 100 units/mL in May 2010. We conducted a 2-year period retrospective observational cohort study comparing the outcomes of using heparin versus citrate locks. Outcomes examined were catheter patency, catheter exchanges, alteplase usage, and catheter infections. RESULTS: During the study period, 84 patients who underwent a total of 554 plasmapheresis treatments were identified. Flow problems among the citrate treatments were more frequent than those among the heparin group (6.5% vs. 3.2%, P = 0.11, n = 554) but this did not reach statistical significance. The frequency of more severe flow problems requiring catheter exchange or alteplase infusion was higher among the citrate group than the heparin group (3.2% vs. 1.3%, P = 0.11, n = 554). Subgroup analysis, stratified by diagnosis, demonstrated that there was a statistically significant difference in flow problems when comparing myasthenia gravis (MG) patients to non-MG patients. There was no difference in catheter infections between the groups. CONCLUSIONS: Based on the findings of our study, we conclude that citrate and heparin locks have similar efficacy in maintaining catheter patency in plasmapheresis patients. Further research is needed to examine the differences observed between MG patients versus all other patients.