BACKGROUND: Treatment of severe methemoglobinemia includes the avoidance of methemoglobin-inducing drugs, the application of methylene blue, and the administration of supplementary oxygen. However, the efficacy of the latter on oxygen transport, tissue oxygenation, and survival in the treatment of extreme methemoglobinemia is ambiguous. The objective was to assess whether using hyperoxic ventilation as the sole therapeutic intervention (i.e., ventilation with pure oxygen, Fio2 1.0) improves the short-term (6-hr) survival rate during otherwise lethal methemoglobinemia. DESIGN: Prospective, randomized, controlled study. SETTING: Experimental animal laboratory of a university hospital. SUBJECTS: Fourteen anesthetized, mechanically ventilated pigs. INTERVENTIONS: After induction of profound methemoglobinemia (60 +/- 2%) by the injection of 15 mg/kg 4-dimethylaminophenol, artificial ventilation either was continued with room air (G 0.21, n = 7) or was changed over to hyperoxic ventilation (G 1.0, n = 7). A constant level of methemoglobinemia was maintained by continuous infusion of 4-dimethylaminophenol throughout a 6-hr follow-up period. MEASUREMENTS AND MAIN RESULTS: All animals died within the 6-hr follow-up period, but survival time was prolonged in animals ventilated with pure oxygen (G 0.21, 105 +/- 30 mins; G 1.0, 210 +/- 64 mins, p < .05). No differences were encountered between G 0.21 and G 1.0 with respect to the investigated variables of macrohemodynamics, oxygen transport, and tissue oxygenation. CONCLUSIONS: Hyperoxic ventilation has negligible effects on oxygen transport and tissue oxygenation during lethal methemoglobinemia; nevertheless, survival was increased without severe adverse reactions provoked by hyperoxic ventilation.
BACKGROUND: Treatment of severe methemoglobinemia includes the avoidance of methemoglobin-inducing drugs, the application of methylene blue, and the administration of supplementary oxygen. However, the efficacy of the latter on oxygen transport, tissue oxygenation, and survival in the treatment of extreme methemoglobinemia is ambiguous. The objective was to assess whether using hyperoxic ventilation as the sole therapeutic intervention (i.e., ventilation with pure oxygen, Fio2 1.0) improves the short-term (6-hr) survival rate during otherwise lethal methemoglobinemia. DESIGN: Prospective, randomized, controlled study. SETTING: Experimental animal laboratory of a university hospital. SUBJECTS: Fourteen anesthetized, mechanically ventilated pigs. INTERVENTIONS: After induction of profound methemoglobinemia (60 +/- 2%) by the injection of 15 mg/kg 4-dimethylaminophenol, artificial ventilation either was continued with room air (G 0.21, n = 7) or was changed over to hyperoxic ventilation (G 1.0, n = 7). A constant level of methemoglobinemia was maintained by continuous infusion of 4-dimethylaminophenol throughout a 6-hr follow-up period. MEASUREMENTS AND MAIN RESULTS: All animals died within the 6-hr follow-up period, but survival time was prolonged in animals ventilated with pure oxygen (G 0.21, 105 +/- 30 mins; G 1.0, 210 +/- 64 mins, p < .05). No differences were encountered between G 0.21 and G 1.0 with respect to the investigated variables of macrohemodynamics, oxygen transport, and tissue oxygenation. CONCLUSIONS: Hyperoxic ventilation has negligible effects on oxygen transport and tissue oxygenation during lethal methemoglobinemia; nevertheless, survival was increased without severe adverse reactions provoked by hyperoxic ventilation.
Authors: Andreas Pape; Harry Kertscho; Jens Meier; Oliver Horn; Mohamed Laout; Max Steche; Mischa Lossen; Alf Theisen; Bernhard Zwissler; Oliver Habler Journal: Intensive Care Med Date: 2008-04-02 Impact factor: 17.440
Authors: Andreas Pape; Saskia Kutschker; Harry Kertscho; Peter Stein; Oliver Horn; Mischa Lossen; Bernhard Zwissler; Oliver Habler Journal: Crit Care Date: 2012-12-12 Impact factor: 9.097