Intravenous lipid emulsion (ILE) is an adjunctive antidote used in selected critically ill poisoned patients. These patients may also require administration of advanced cardiac life support (ACLS) drugs. Limited data is available to describe interactions of ILE with standard ACLS drugs, specifically epinephrine. Twenty rats with intra-arterial and intravenous access were sedated with isoflurane and split into ILE or normal saline (NS) pretreatment groups. All received epinephrine 15 μm/kg intravenously (IV). Continuous mean arterial pressure (MAP) and heart rate (HR) were monitored until both indices returned to baseline. Standardized t tests were used to compare peak MAP, time to peak MAP, maximum change in HR, time to maximum change in HR, and time to return to baseline MAP/HR. There was a significant difference (p=0.023) in time to peak MAP in the ILE group (54 s, 95 % CI 44-64) versus the NS group (40 s, 95 % CI 32-48) and a significant difference (p=0.004) in time to return to baseline MAP in ILE group (171 s, 95 % CI 148-194) versus NS group (130 s, 95 % CI 113-147). There were no significant differences in the peak change in MAP, peak change in HR, time to minimum HR, or time to return to baseline HR between groups. ILE-pretreated rats had a significant difference in MAP response to epinephrine; ILE delayed the peak effect and prolonged the duration of effect of epinephrine on MAP, but did not alter the peak increase in MAP or the HR response.

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Objectives: The anticoagulant dabigatran has no reversal agent and may cause life-threatening bleeding in patients with trauma or closed-space hemorrhage. Intravenous lipid emulsion (ILE) is thought to create a lipid compartment in serum that sequesters lipophilic drugs. Dabigatran is lipophilic, and its anticoagulant effects are concentration dependent. The study objective was to determine if ILE therapy reverses dabigatran's anticoagulant effects.Methods: Twenty rats were selected at random, 10 in the ILE group and 10 in a normal saline (NS) control group. Animals had a baseline tail bleeding time (T0), followed by oral dabigatran administration (15 mg/kg). At 45 minutes (T45), a second tail bleed time measurement was performed, followed by a 7-minute infusion of 15 mL/kg ILE or NS. A final 60-minute (T60) bleed time measurement was obtained. An ILE-only group of five animals had bleeding times assessed prior to (T0) and 15 minutes after (T15) ILE therapy. A mixed-effect repeated-measures analysis of variance modeling the effect of time, group, and the interaction of group and time on bleed times was conducted.Results: There was a significant within-subject change in bleeding time across the assessment points (F (2,36) = 33; p < 0.001), but there were no effect of group (F(1,18) = 1.42, p = 0.25) or an interaction between group and assessment point on mean bleeding time (F(2,36) = 0.59, p = 56). Between T0 and T45, average bleeding times increased from 109.5 seconds (95% confidence interval [CI] = 94 to 125 seconds) to 231.8 seconds (95% CI = 193 to 271 seconds; p < 0.0001) for both the ILE group and the NS control group. Between T45 and T60, bleeding times in the ILE group decreased by 31.5 seconds (95% CI = -77 to 14 seconds) and by 6 seconds (95% CI = -67 to 55 seconds) in the NS group (p = 0.46). In the five ILE-only animals, the average bleeding time at T0 was 114 seconds (95% CI = 62 to 166 seconds), which increased significantly at T15 to 237 seconds (95% CI = 161 to 313 seconds; p = 0.02). Conclusions:The anticoagulant effects of dabigatran are not reversed with ILE therapy. Although ILE itself significantly prolonged bleeding times, when administered to dabigatran-anticoagulated rats, bleeding times did not change significantly. There may be a complex interaction of ILE with dabigatran that this study was not able to elucidate.