Caracterización del uso de emulsiones lipídicas como terapia antidotal en intoxicaciones diferentes a anestésicos locales en un centro de alta complejidad en Medellín / Characterization of the use of lipid emulsions as antidotal therapy in intoxications other than local anesthetics in a high complexity center in Medellin

Introducción. Las emulsiones lipídicas intravenosas (ELI) son unas emulsiones grasas no tóxicas con fosfolípidos, actualmente aprobadas para su uso en el tratamiento de intoxicaciones, específicamente en las producidas por anestésicos locales. El propósito de este estudio es la caracterización del uso de ELI en pacientes mayores de 18 años, que presentaron intoxicación por sustancias y medicamentos diferentes a anestésicos locales, en un hospital de alta complejidad de la ciudad de Medellín, durante el periodo comprendido entre 2015 y 2020. Metodología. Se realizó un estudio descriptivo, retrospectivo, de casos que recibieron ELI como tratamiento para su intoxicación. Se hizo revisión de las historias clínicas de la población objeto de estudio. Se recolectó información acerca de variables sociodemográficas, clínicas y paraclínicas, y de atención. Se hizo análisis univariado de las variables de interés. Resultados. Del total de 1.966 intoxicaciones, se incluyeron 51 (2,6 %) casos de intoxicación por sustancias y medicamentos diferentes a anestésicos locales, que recibieron la terapia con ELI entre 2015 y 2020. La mediana de edad de los participantes fue de 27 años. Un 74,5 % de los participantes presentó intoxicación por medicamentos. El promedio de la dosis de ELI recibida fue de 1.036 mL en 24 horas, dosis inferior a la calculada por kilo de peso que debían recibir, de 1.149 mL en promedio. Un 86,3 % (n=44) de los casos presentaron neurotoxicidad, y 76,5 % (n=39) presentaron cardiotoxicidad. La neurotoxicidad mejoró en el 34,7 % y la cardiotoxicidad en el 59,1 % de los individuos que recibieron terapia con ELI. Conclusión. La aplicación de las ELI se hizo en personas en su mayoría intoxicadas por antipsicóticos, hombres, jóvenes; menos de la mitad tenía compromiso de la ventilación, y hubo mejoría en la cardiotoxicidad y neurotoxicidad. Hubo una diferencia entre la dosis recibida y la que debían recibir ajustada por el peso

Introduction. Intravenous lipid emulsions (IVLE) are non-toxic fatty emulsions with phospholipids, currently approved for use in the treatment of poisoning, specifically those produced by local anesthetics. The purpose of this study is to characterize the use of IVLE in patients over 18 years of age, who presented intoxication by substances and medications other than local anesthetics, in a high complexity hospital in the city of Medellín, during the period between 2015 and 2020. Methodology. A retrospective descriptive study was carried out on cases that received IVLE as a treatment for their poisoning. The clinical records of the study population were reviewed. Information was collected about sociodemographic, clinical and paraclinical variables, and care. Univariate analysis of the variables of interest was performed. Results. Of the total of 1,966 poisonings, 51 (2.6%) cases caused by substances and medications other than local anesthetics, received ELI therapy between 2015 and 2020 and were included in the study. The median age of the participants was 27 years. 74.5% of the participants presented drug poisoning. The average IVLE dose received was 1,036 mL in 24 hours, a lower dose than the one calculated per kilo of weight, which had been on average 1,149 mL. 86.3% (n=44) of the cases presented neurotoxicity, and 76.5% (n=39) presented cardiotoxicity. Neurotoxicity improved in 34.7% and cardiotoxicity in 59.1% of individuals receiving ELI therapy. Conclusion. The application of IVLE was made in people mostly poisoned by antipsychotics, men, young people, less than half had compromised ventilation, and there was improvement in cardiotoxicity and neurotoxicity. There was a difference between the dose received and the one they should have received adjusted for weight

Intoxicación sistémica por anestésicos locales / Systemic intoxication by local anesthetics

Resumen: Los anestésicos locales se definen como fármacos que bloquean la generación y propagación de impulsos en tejidos excitables desde médula ósea, raíces nerviosas, nervios periféricos hasta otros tejidos excitables como músculo cardíaco, músculo liso y cerebro. La intoxicación sistémica se produce debido a las concentraciones plasmáticas elevadas después de altas dosis o la administración intravenosa inadvertida. El creciente uso de técnicas de anestesia locorregional obliga a tener presente la intoxicación sistémica por anestésicos locales como una complicación anestésica de baja incidencia, pero alta morbimortalidad, además de constituir una de las causas de paro cardiorrespiratorio de origen anestésico más frecuentes. La presentación clínica de esta complicación es muy variable y abarca un gran espectro de síntomas relacionados principalmente con la toxicidad neurológica y cardiovascular. Aunque infrecuentes, las reacciones pueden ser muy graves, y resultar en daño irreversible o muerte del paciente. La prevención parece haber disminuido la intoxicación de los anestésicos locales y es más efectiva que el tratamiento. El manejo se basa en medidas de reanimación cardiopulmonar avanzada, el tratamiento farmacológico y el empleo precoz de las emulsiones lipídicas. Se presenta un caso de intoxicación sistémica utilizando lidocaína simple como único anestésico local durante la realización de bloqueo de nervio periférico en cirugía electiva.

Abstract: The local anesthesics are defined as medicaments that block the generation and spread of impulses in excitable fabrics, from bony marrow, nervous roots, peripheral nerves or other excitable fabrics as cardiac muscle, smooth muscle and brain. The systemic intoxication takes place due to the plasmatic concentrations raised after high doses or the intravenous inadvertent administration. The increasing use of technologies of anesthesia locorregional forces to bear in mind the systemic intoxication for local anesthesics as an anesthesic complication of low incident, but high morbi-mortality, beside constituting one of the more frequent reasons of cardiorespiratory unemployment of anesthesic origin. The clinical presentation of this complication is very variable and includes a great spectrum of symptoms related principally to the neurological and cardiovascular toxicity. Though infrequent, the reactions can be very serious, and to result in irreversible hurt or death of the patient. The prevention seems to have diminished the poisoning of the local anesthesics and is more effective than the treatment. The managing is based on measures of resuscitation cardiopulmonar advanced, the pharmacological treatment and the precocious employment of the lipid emulsions. I present a case of systemic intoxication using lidocaine simply as anesthesic local only one during the accomplishment of blockade of peripheral nerve in elective surgery.

Uso de emulsiones lipídicas en el tratamiento exitoso de un caso de intoxicación por difenhidramina / Use of lipid emulsions in the successful treatment of a case of diphenhydramine poisoning / Uso de emulsões lipídicas no sucesso do tratamento de um caso de intoxicação por difenidramina

La difenhidramina tiene efectos antihistamínico anti-H1 específico y antimuscarínico que pueden ocasionar un desenlace fatal según la dosis total ingerida. Se reporta un caso de intoxicación por difenhidramina tratado de forma exitosa con emulsiones lipídicas a pesar de ingesta de dosis letal. Se presenta el caso de un paciente de 19 años que ingresó por intoxicación por difenhidramina a dosis de 25 mg/kg (1.5 g) después del tiempo de descontaminación, con toxidrome anticolinérgico, con neurotoxicidad, cardiotoxicidad (QRS y QT prolongados) y sin respuesta al enfoque inicial, se iniciaron emulsiones lipídicas y, a su vez, se logró alta temprana por evolución clínica favorable y resolución de la prolongación del intervalo QTc y del cuadro anticolinérgico. La emulsión lipídica es una opción terapéutica para disminuir la morbimortalidad y la estancia hospitalaria por contrarrestar la cardiotoxicidad y neurotoxicidad producidas por moléculas lipofílicas como la difenhidramina.

Diphenhydramine has specific anti-H1 antihistamine and antimuscarinic effects that can be fatal depending on the total dose ingested. A case of diphenhydramine poisoning successfully treated with lipid emulsions despite ingesting a lethal dose is presented. We present the case of a 19-year-old patient who was admitted for diphenhydramine intoxication at a dose of 25 mg/kg (1.5 g) after the decontamination time, with anticholinergic toxidrome, with neurotoxicity, cardiotoxicity (prolonged QRS and QT) and without response to initial approach. Lipid emulsions were started and, in turn, early discharge was achieved due to favorable clinical evolution and resolution of the prolongation of the QTc interval and the anticholinergic symptoms. Lipid emulsion is a therapeutic option to reduce morbidity and mortality and hospital stay by counteracting cardiotoxicity and neurotoxicity produced by lipophilic molecules such as diphenhydramine.

A difenidramina tem efeitos anti-histamínicos e antimuscarínicos anti-H1 específicos que podem ser fatais dependendo da dose total ingerida. Relata-se um caso de intoxicação por difenidramina tratada com sucesso com emulsões lipídicas apesar da ingestão de uma dose letal. Apresentamos o caso de uma paciente de 19 anos que foi internada por intoxicação por difenidramina na dose de 25 mg/kg (1,5 g) após o tempo de des-contaminação, com toxina anticolinérgica, neurotoxicidade, cardiotoxicidade (QS e QT prolongados) e sem resposta na abordagem inicial, iniciaram-se emulsões lipídicas e, por sua vez, obteve-se alta precoce devido à evolução clínica favorável e resolução do prolongamento do intervalo QTc e dos sintomas anticolinérgicos. A emulsão lipídica é uma opção terapêutica para reduzir a morbimortalidade e o tempo de internação por neutralizar a cardiotoxicidade e a neurotoxicidade produzidas por moléculas lipofílicas como a difenidramina.

Lipid emulsion therapy of local anesthetic systemic toxicity due to dental anesthesia

Local anesthetic systemic toxicity (LAST) refers to the complication affecting the central nervous system (CNS) and cardiovascular system (CVS) due to the overdose of local anesthesia. Its reported prevalence is 0.27/1000, and the representative symptoms range from dizziness to unconsciousness in the CNS and from arrhythmias to cardiac arrest in the CVS. Predisposing factors of LAST include extremes of age, pregnancy, renal disease, cardiac disease, hepatic dysfunction, and drug-associated factors. To prevent the LAST, it is necessary to recognize the risk factors for each patient, choose a safe drug and dose of local anesthesia, use vasoconstrictor , confirm aspiration and use incremental injection techniques. According to the treatment guidelines for LAST, immediate application of lipid emulsion plays an important role. Although lipid emulsion is commonly used for parenteral nutrition, it has recently been widely used as a non-specific antidote for various types of drug toxicity, such as LAST treatment. According to the recently published guidelines, 20% lipid emulsion is to be intravenously injected at 1.5 mL/kg. After bolus injection, 15 mL/kg/h of lipid emulsion is to be continuously injected for LAST. However, caution must be observed for >1000 mL of injection, which is the maximum dose. We reviewed the incidence, mechanism, prevention, and treatment guidelines, and a serious complication of LAST occurring due to dental anesthesia. Furthermore, we introduced lipid emulsion that has recently been in the spotlight as the therapeutic strategy for LAST.

Effect of ω-3 polyunsaturated fatty acids and ω-6 polyunsaturated acids on Toll-like receptor /nuclear fac-tor-κB signaling pathway and the inflammatory cytokines in neonatal rats with brain injury induced by lipopolysaccharide / 中华实用儿科临床杂志

Objective To investigate the effects of ω-3 polyunsaturated fatty acids(ω-3PUFAs)and ω-6 polyunsaturated fatty acids(ω-6PUFAs)on Toll-like receptor 4(TLR4)/nuclear factor-κB(NF-κB)signaling pathway,and the expressions of tumor necrosis factor-α(TNF-α),interleukin(IL)-1β and IL-6 in neonatal rats with brain injury induced by lipopolysaccharide (LPS). Methods Ninety-six neonatal rats were divided into control group,ω-3PUFAs group,ω-6PUFAs group,and LPS group by using random number table method. Intraperitoneal injection of LPS was performed in LPS group,ω-6PUFAs group and ω-3PUFAs group to establish models of rat brain injury. The rats in control group received 9 g/L saline. Twelve newborn rats were killed at 1 d or 5 d after intraperito-neal injection in each group for hippocampus selection. Real -time PCR and Western blot were used to detect the mRNA and protein expression levels of TLR4,NF-κB,TNF-α,IL-1β and IL-6. Results One day after mode-ling,TLR4,NF-κB,TNF-α,IL-1β and IL-6 mRNA expressions in ω-3PUFAs group (10. 63 ± 0. 07,5. 86 ± 1. 05,7. 65 ± 2. 29,5. 23 ± 1. 31,3. 36 ± 0. 72)were lower than those in ω-6PUFAs group (18. 83 ± 2. 10,8. 79 ± 2. 08,11. 95 ± 3. 23,10. 97 ± 2. 24,6. 37 ± 1. 17)and LPS group (15. 76 ± 1. 59,7. 13 ± 1. 10,9. 71 ± 2. 14,7. 83 ± 0. 85,4. 78 ± 0. 51),and the differences were all statistically significant(all P＜0. 05);which in ω-6PUFAs group were higher than those in LPS group,and the differences were all significant (all P＜0. 05). TLR4,NF-κB,TNF-α, IL-1β and IL-6 protein levels in ω-3PUFAs group (1. 57 ± 0. 11,1. 58 ± 0. 09,1. 55 ± 0. 09,1. 63 ± 0. 31,1. 36 ± 0. 12)were lower than those in ω-6PUFAs group (1. 96 ± 0. 17,2. 21 ± 0. 12,1. 95 ± 0. 23,1. 97 ± 0. 24,1. 77 ± 0. 17)and LPS group (1. 73 ± 0. 15,1. 87 ± 0. 10,1. 79 ± 0. 14,1. 83 ± 0. 15,1. 58 ± 0. 11)in 1 d,and the diffe-rences were all significant (all P＜0. 05),and those in ω-6PUFAs group were higher than those in LPS group (all P＜0. 05). Similarly,TLR,NF-κB,TNF-α,IL-1β and IL-6 mRNA and protein expression levels in ω-3PUFAs group (3. 78 ± 0. 88,3. 86 ± 0. 62,6. 26 ± 1. 94,3. 65 ± 1. 44,2. 11 ± 0. 87;1. 15 ± 0. 08,1. 32 ± 0. 10,1. 46 ± 0. 04, 1. 38 ± 0. 14,1. 21 ± 0. 09)were lower than those in ω-6PUFAs group (7. 76 ± 1. 65,5. 51 ± 0. 88,7. 96 ± 2. 13,5. 35 ± 1. 75,4. 88 ± 1. 35;1. 42 ± 0. 15,1. 51 ± 0. 36,1. 65 ± 0. 13,1. 72 ± 0. 23,1. 48 ± 0. 10)and LPS group (6. 21 ± 1. 87, 4. 98 ± 0. 73,7. 11 ± 2. 10,4. 84 ± 1. 75,4. 25 ± 0. 64;1. 35 ± 0. 13,1. 44 ± 0. 22,1. 59 ± 0. 10,1. 61 ± 0. 18,1. 35 ± 0. 07) in 5 d (all P＜0. 05),and which in ω-6PUFAs group were higher than those in LPS group,and the differences were sig-nificant (all P＜0. 05). Conclusion ω-6PUFAs can up-regulate the activity of TLR4,NF-κB,and reduce the re-lease of TNF-α,IL-1β and IL-6;and ω-3PUFAs can down-regulate the activity of TLR4,NF-κB,and reduce the release of TNF-α,IL-1β and IL-6,so it has a neural protective effect in brain injury induced by LPS.

Effects of different administration routes of lipid emulsion on bupivacaine-induced cardiotoxicity in rats / 中华麻醉学杂志

Objective To evaluate the effects of different administration routes of lipid emulsion on bupivacaine-induced cardiotoxicity in rats.Methods Forty-eight clean healthy adult male Sprague-Dawley rats,weighing 300-350 g,were divided into 6 groups (n=8 each) using a random number table:Ⅳ infusion of normal saline (NS) group (group VN),Ⅳ infusion of lipid emulsion group (group VL),duodenal infusion of NS group (group DN),duodenal infusion of lipid emulsion group (group DL),intraperitoneal intusion of NS group (group PN) and intraperitoneal infusion of lipid emulsion group (group PL).In VN and VL groups,preheated NS and 20％ lipid emulsion 3 ml · kg-1 · min-1 were infused via the femoral vein for 5 min,respectively,and then 0.75％ bupivacaine was infused at the rate of 2 mg · kg-1 · min-1 until cardiac arrest happened.Preheated NS and 20％ lipid emulsion 15 ml/kg were infused via the duodenum (over 1 min,at a constant rate) in DN and DL groups,respectively,and were intraperitoneally infused in PN and PL groups,respectively,followed by an infusion of 0.2 ml/min for 15 min in DN,DL,PN and PL groups.Then 0.75％ bupivacaine was infused via the left femoral vein at a rate of 2 mg · kg-1 · min-1 until cardiac arrest happened.The time to ventricular arrhythmia,mean arterial pressure (MAP) decreasing to 50％ of the baseline and cardiac arrest was recorded.The amount of bupivacaine consumed was calculated immediately after ventricular arrhythmia occurred (T0),immediately after MAP decreased to 50％ of the baseline (T1) and immediately after occurrence of cardiac arrest (T2).Arterial blood samples were collected at T0-2 for determination of the concentration of bupivacaine in plasma by high-performance liquid chromatography.Results Compared with group VN,the time to ventricular arrhythmia,MAP decreasing to 50％ of the baseline and cardiac arrest was significantly prolonged,and the amount of bupivacaine consumed was increased at T0-2 in group VL (P＜0.01).There was no significant difference in the parameters mentioned above between group DN and group DL,and between group PN and group PL (P＞0.05).Compared with group VL,the time to ventricular arrhythmia,MAP decreasing to 50％ of the baseline and cardiac arrest was significantly shortened,and the amount of bupivacaine consumed was decreased at T0-2 in DL and PL groups (P＜0.01).Compared with group DL,the time to ventricular arrhythmia,MAP decreasing to 50％ of the baseline and cardiac arrest was significantly prolonged,and the amount of bupivaeaine consumed was increased at T0.2 in group PL (P＜0.05).There was no significant difference in the concentration of plasma bupivacaine between six groups (P＞0.05).Conclusion Ⅳ infusion of lipid emulsion can decrease bupivacaine-induced cardiotoxicity when compared with duodenal and intraperitoneal infusion in rats.

Effects of postoperative parenteral nutrition with different lipid emulsions in patients undergoing major abdominal surgery

PURPOSE: This study was designed to investigate the effects of total parenteral nutrition (PN) using different lipid emulsions in patients undergoing major abdominal surgery. METHODS: Fifty-two patients were randomized to receive soybean oil + medium chain triglycerides (MCT) (group I), soybean oil + olive oil (group II), soybean oil + olive oil + fish oil (group III) as a lipid source. PN was started on postoperative day 1 and patients were maintained on PN for a minimum period of 4 days. Laboratory variables (CRP, prealbumin, transferrin) were measured before surgery and on postoperative days. RESULTS: Three treatment groups were included in the study. Patients in group I received long chain triglycerides (LCT) + LCT/MCT emulsion (%75 LCT + %25 LCT/MCT); Patients in group II received olive oil based emulsion (80% olive oil + 20% soybean oil, ClinOleic); Patients in group III received fish oil in addition to olive oil based emulsion (%85 ClinOleic + %15 Omegaven; Fresenius Kabi). The following 14 parameters were assessed: body weight, CRP, prealbumin, transferrin, tumor necrosis factor-α, interleukin-6, total antioxidant status, thiobarbituric acid reactive substances, oxidized low density lipoprotein-2, complete blood cell, international normalized ratio, D-dimer, activated partially thromboplastin time, prothrombin time. All other parameters showed no differences among the groups. CONCLUSION: The results of our trial demonstrate a potential beneficial effect of soybean oil/olive oil based lipid emulsions for use in PN regarding inflammatory response and oxidant capacity in the treatment of patients.

Effect of Intravenous Lipid Emulsion in the Patient with Acute Poisoning : A Systematic Review

PURPOSE: The purpose of this study was to evaluate the usefulness of intravenous lipid emulsion as well as adverse events in acute poisoning patients. METHODS: Literature was accessed through PubMed, EMBASE, Cochrane library, Web of science, and KoreaMed. All forms of literatures relevant to human use of intravenous lipid emulsion for acute poisoning were included. Cases reports or letters without description of clinical outcomes for each case were excluded. The literature search was conducted by two investigators in March, 2015, with publication language restricted to English and Korean. The effect, onset time, and adverse event of lipid emulsion and final outcome of each case were analyzed. RESULTS: Eighty-one published articles were included, excluding articles whose title and abstract were not relevant to this study. No articles were classified as high level of evidence. Sixty-eight case reports were identified, consisting of 25 local anesthetics and 43 other drugs, such as tricyclic antidepressants and calcium channel blockers. Although most cases described significant clinical improvements, some of them showed no beneficial effect or worsening of clinical course. Several adverse events including hyperamylasemia and laboratory interference were reported. CONCLUSION: Although there were many case reports illustrating successful use of lipid for various drug poisonings, the effect cannot be estimated due to significant possibility of publication bias. Therefore, lipids might be considered in severe hemodynamic instability resulting from lipophilic drug poisoning, however further studies should follow to establish the use of lipid as the standard of care.

Lipid Emulsion in the Successful Resuscitation of Local Anesthetic Toxicity after Ankle Block / 대한구급학회지

Unexpected occurrence of local anesthetic toxicity is not rare and can cause fatal complications that do not respond to any known drug of intervention. Recently, the successful use of lipid emulsion for local anesthetic toxicity has been reported and recommended as a rescue method for cardiac or neurologic complications. We report a case of seizure attack and respiratory arrest successfully recovered with the use of intravenous lipid emulsion. Clinicians must be aware of the beneficial role of lipid emulsion in cases of local anesthetic toxicity.

Preparation, Characteristics and in vitro Drug Release of Silybin Lipid Emulsions / 中国药师

Objective:To prepare silybin ( SLB) lipid emulsions and evaluate the drug release behavior in vitro. Methods:Silybin lipid emulsions were prepared by high-pressure homogenization method. Under the guidance of single-factor test, the best formula of SLB lipid emulsions was obtained by orthogonal design. Results:The encapsulation efficiency of SLB lipid emulsions prepared by the optimal formula was (91. 45 ± 0. 005 2) % with the particle size of (74. 42 ± 14)nm and PDI of 0. 106, Zeta potential of ( -30. 2 ± 2. 13)mV and pH of (6. 48 ± 0. 04). The drug release of SLB lipid emulsions was up to 90% within 12 hours. Conclusion:The opti-mized preparation of SLB with sustained-release property is obtained successfully.

Effect of continuous infusion of lipid emulsions on endotoxin induced acute lung injury and mechanism in rats / 临床儿科杂志

10.3969/j.issn.1000-3606.2013.06.016

Role of dextran sulfate in the catabolism of lipid emulsions / 中华临床营养杂志

ObjectiveTo investigate the effects of scavenger receptor A on the catabolism of lipid emulsions and further to see if it differently affects long-chain triglyceride (LCT) and fish oil (FO) emulsions. MethodsA total of 24 C57BL/6J female mice, 10 to 12 weeks old, were randomly divided into 4 groups with 6 mice in each group. Two groups of mice were intravenously injected with dextran sulfate ( DexSO4 ) ( 1 mg/mouse) followed by intravenous injection of [1α, 2α(n)-3H] cholesteryl oleoyl ether [(3H)CEt] labelled LCT or FO emulsions (0.4mg triglycerde/mouse) at 2 minutes respectively, and other two groups were injected by saline as controls before injection of (3H)CEt labelled LCT and FO emulsions. Then, blood was drawn at fixed intervals to measure the radioactivities and the emulsion's fractional catabolic rates (FCR) were calculated. With the same procedures above mentioned, non-radiolabelled LCT and FO emulsions were intravenously injected to mice to determine liver uptake of lipid emulsions under electromicroscopy. Finally, THP1 cell line was used to examine the effects of DexSO4 on cell uptake of LCT and FO emulsions in vitro. ResultsPre-injection of DexSO4 to mice decreased the FCR of both LCT and FO emulsions at 72.38％ and 47.38％ respectively, as compared to controls ( P =0.020 ). Electromicroscopy showed that pre-injection of DexS04 decreased the uptakes of LCT and FO emulsions by Kupffer cells and sinusoidal endothelial cells similarly. In hepatocytes, no lipid droplets existed in mice with LCT emulsion injection, whereas some lipid droplets were still shown in mice with FO emulsions but with less quantities compared to control mice.In vitro, addition of DexSO4 to medium decreased THP1 cell uptakes of LCT and FO emulsions ( P =0.003 and 0.008) by 30.74％ and 41.60％ respectively. However, no differences were found in the effects of DexS04 on cell uptakes between LCT and FO emulsions ( P =0.080). ConclusionScavenger receptor A plays important roles in catabolism of lipid emulsions to some extent, and it's effects on FO emulsions may be less than LCT emulsions.

Effect of 8% emulsified isoflurane postconditioning on focal cerebral ischemia-reperfusion injury in rats / 中华麻醉学杂志

Objective To investigate the effect of postconditioning with 8 % emulsified isoflurane (EI) on focal cerebral ischemia-reperfusion (I/R) injury in rats. Methods Forty-eight male SD rats weighing 260-300 g were randomly divided into 6 groups ( n = 8 each): group Ⅰ sham operation (group S); group Ⅱ I/R; group Ⅲ,Ⅳ, Ⅴ 3 different doses of EI (group L-EI, M-EI, H-.EI) and group Ⅵ lipid emulsion (group LE). Right middle cerebral artery occlusion (MCAO) was induced by inserting a nylon thread 0.24 mm in diameter into right internal carotid artery. The thread was threaded cranially until resistance was met. MCAO was maintained for 2 h followed by 24 h reperfusion in group Ⅱ-Ⅵ. In group Ⅲ-Ⅴ EI 3.5, 7.0 and 10.5 ml/kg were injected intraperitoneally (IP) immediately before reperfusion respectively. In group LE 30% lipid emulsion 10.5 ml/kg was given instead of EI. The neurologic deficit was assessed and scored (0 = normal, 4 = unable to move and unconscious). The animals were then killed and infarct size was measured. Results IP 8% emulsified isoflurane 7.0 and 10.5 ml/kg injected before reperfusion significantly reduced neurologic deficit scores and infarct size in group M-EI and H-EI as compared with group I/R. Conclusion Postconditioning with 8% emulsified isoflurane can protect the brain against focal cerebral I/R injury.