The impact of intravenous lipid emulsion on lipophilicity in poisoned patients: A systematic review. Evvah Karakılıç 1* , Elif Kaya 2 , Ahmet Erdem 2 , Engin Deniz Arslan 3 , Tamer Durdu 2 , Serkan Tulgar 4 , Doğan Işcanlı 2 1 Department of Emergency Medicine, Faculty of Medicine, Eskisehir Osmangazi University, Eskisehir, Turkey 2 Ankara Numune Training and Research Hospital, Emergency Medicine Clinic, Altındağ, Ankara, Turkey 3 Ankara Dışkapı Yıldırım Beyazıt Education and Research Hospital, Emergency Medicine Clinic, Altındağ, Ankara, Turkey 4 Department of Anesthesia and Reanimation, Faculty of Medicine, Maltepe University, İstanbul, Turkey Abstract Objective: Although the action mechanism of intravenous lipid emulsion has not been fully elucidated yet, its use in liposoluble drugs intoxications. In this study, we examined the lipophilic features of causative agents and the success of the treatment ILE therapy in intoxication cases. Methods: We reviewed 765 cases published in PubMed between 1966 and June, 2015. After applying exclusion criteria, totally 141 cases ingested single substance and received ILE therapy with 20% ILE solution were included in present study. Amount of lipid solutions given and the results were recorded. Success rate was statistically assessed according to log p values of the substances taken and the amount of lipid emulsion used. Results: 141 patients were involved in this study; log p values were calculated for all drugs regardless of the success of ILE therapy. ILE therapy under the amount of 100 ml failed to achieve successful outcome. ALOGPS and ChemAxon log P values were higher in cases, which received ILE therapy ≤ 500 ml and showed successful results. It was found that log p value had no contribution to the treatment success in the group received ILE therapy>500 ml. Conclusions: It was found that ILE therapy<500 ml was successful in drugs with higher lipophilicity while success rate was higher in ILE therapy>500 ml and that liposolubility had no significant contribution to treatment success. Keywords: Intravenous lipid emulsion, Lipophilicity, Poisoning. Accepted on July 17, 2017 Introduction In recent years, the lipid emulsions used for nutrition were introduced as an antidote in life-threatening drug intoxications. Weinberg et al. reported the Intravenous Lipid Emulsion (ILE) therapy given after severe bupivacaine intoxication to be effective in resuscitation in intact rats [1]. Since then, it was shown that lipid emulsions are effective in the treatment of accidental or intentional drug intoxications in many case reports and animal studies [2-7]. Although many studies were carried out on ILE, its mechanism of action couldn’t be completely understood. However, various theories were proposed on the pharmacodynamics and pharmacokinetic aspects. First of all, a theory proposing pharmacological sink for liposoluble drugs, which is also termed as lipid sink theory, was considered [8,9]. In lipid sink theory, it is proposed that the lipid emulsion creates an expanded lipid phase, resulting in redistribution; thus, lipid emulsion leads the toxic drugs to pass into the plasma, where they then pass to the lipid phase [9,10]. In a rat study, it was found that ILE given after bupivacaine injection decreased the concentration of bupivacaine in heart, brain, lung, kidney and spleen via redistribution [11]. In this theory, liposoluble drugs would better pass into lipid phase. Liposolubility of a drug is generally represented by logarithmic presentation (log10) of distribution between octanol and water (octanol-water partition coefficients; log p or log d (distribution-coefficient) [12]. According to this statement, drugs with higher log p value would be more lipophilic. Second theory is the enhancement of cardiac energy support. Fatty acids are primary energy source in non-stressed, resting heart. In previous studies, it was shown that supplementation with fatty acids increased the performance in ischemic, hypo-dynamic heart [8,13]. Another action mechanism that was proposed is the direct cardiotonic ISSN 0970-938X www.biomedres.info Biomed Res- India 2017 Volume 28 Issue 16 7060 Biomedical Research 2017; 28 (16): 7060-7069