Faculty Bibliography

OBJECTIVE: Acetaminophen-induced fulminant hepatic failure is associated with acute kidney injury, metabolic acidosis, and fluid and electrolyte imbalances, requiring treatment with renal replacement therapies. Although antidote, acetylcysteine, is potentially extracted by renal replacement therapies, pharmacokinetic data are lacking to guide potential dosing alterations. We aimed to determine the extracorporeal removal of acetylcysteine by various renal replacement therapies. METHODS: Simultaneous urine, plasma and effluent specimens were serially collected to measure acetylcysteine concentrations in up to three stages: before, during and upon termination of renal replacement therapy. Alterations in pharmacokinetics were determined by applying standard pharmacokinetic equations. RESULTS: Over 2 years, 10 critically ill patients in fulminant hepatic failure requiring renal replacement therapy coincident with acetylcysteine were consecutively enrolled. All 10 patients required continuous venovenous hemofiltration (n = 10) and 2 of the 10 also required hemodialysis (n = 2). There was a significant alteration in the pharmacokinetics of acetylcysteine during hemodialysis; the area under the curve (AUC) decreased 41%, the mean extraction ratio was 51%, the mean hemodialytic clearance was 114.01 ml/kg/h, and a mean 166.75 mg/h was recovered in the effluent or 41% of the hourly dose. Alteration in the pharmacokinetics of acetylcysteine during continuous venovenous hemofiltration did not appear to be significant: the AUC decreased 13%, the mean clearance was 31.77 ml/kg/h and a mean 62.12 mg/h was recovered in the effluent or 14% of the hourly dose. CONCLUSIONS: There was no significant extraction of acetylcysteine from continuous venovenous hemofiltration. In contrast, there was significant extracorporeal removal of acetylcysteine during hemodialysis. A reasonable dose adjustment may be to double the IV infusion rate or possibly supplement with oral acetylcysteine during hemodialysis.

PURPOSE: To assess pharmacists' and students' knowledge of high-dose insulin euglycemia (HIE) and intravenous fatty acid emulsion 20% (IFE) and to see whether it improved after an educational intervention. METHODS: A survey to assess the knowledge about the use of HIE and IFE as antidotes was e-mailed to practicing pharmacists, pharmacy residents, and students prior to and following an educational intervention. Fact sheets on the antidotes were developed in conjunction with the New York City Poison Control Center and were used as the educational intervention in this study. The impact of exposure to the intervention was measured by comparing the number of correct responses per question on the pre- and posttests and the mean pre- and posttest scores using chi-square and t tests, respectively. RESULTS: Most respondents felt either not at all or only somewhat comfortable with managing a toxicologic emergency. There was a statistically significant difference in mean scores on the pretest and posttest (2.9 vs 5.45; P = .001) and for the number of participants giving correct responses for each question before and after education: 52.4% of respondents answered "I don't know" to the questions prior to education versus 21.2% after education (P < .001). Fewer respondents felt not at all comfortable managing a toxicologic emergency after the educational intervention (42.4 vs 50.3%; P < .001). CONCLUSION: Pharmacists and students reported little comfort in managing toxicological emergencies in general and have limited baseline knowledge about these agents. Educational interventions can significantly improve knowledge. Prior familiarity with these newer antidotes should reduce delays in their administration in an emergency.