Effects of propofol in lipid-based emulsion and in microemulsion on the incidence of endothelial lesion in rabbits

PURPOSE: To compare the incidence of endothelial injury after single-dose or continuous propofol infusion in conventional lipid-based emulsion (LE) versus microemulsion (ME). METHODS: Forty-two rabbits (2.5-4.5 Kg) were randomly allocated into seven groups of six animals each: SHAM- surgical treatment alone; Bolus Control Group - 3 mL-intravenous (IV) bolus of saline; Continuous Infusion Control Group - 3 mL- IV bolus of saline followed by a continuous infusion of 0.2 ml/kg/min for 60 min; Bolus LE Propofol Group - IV bolus of LE propofol (3 mg/kg); Bolus ME Propofol Group - IV ME propofol bolus (3 mg/kg); Continuous LE Propofol Group - IV LE propofol bolus (3 mg/kg) followed by a continuous infusion of 0.2 ml/kg/min for 60 min; Continuous ME Propofol Group - IV ME propofol bolus (3 mg/kg) followed by a continuous infusion of 0.2 ml/kg/min for 60 min. RESULTS: There were no statistically significant differences between the studied groups in blood pressure, in central venous pressure and in the biochemical profile. No significant differences were found in inflammatory mediators and in tissue analysis between the two emulsions. CONCLUSION: Microemulsion and lipid-based emulsion propofol had similar inflammatory, biochemical and microscopy profiles. Thus, microemulsion propofol can be used as an alternative to lipid-based emulsion propofol.

Pressão arterial, respostas metabólicas e autonômicas à insulina e infusão de intralipid® em pacientes chagásicos / Blood pressure, metabolic and autonomic responses to insulin and intralipid® infusion in chagasic patients / Presión arterial, respuestas metabólicas y autonómicas a la insulina e infusión de intralipid® en pacientes chagásicos

FUNDAMENTO: Infusão de intralipid e heparina resulta em aumento da pressão arterial e também em anormalidades autonômicas em indivíduos normais e hipertensos. OBJETIVO: Avaliar a sensibilidade a insulina e o impacto da infusão de intralipid e de heparina (ILH) sobre a resposta hemodinâmica, metabólica e autonômica em pacientes com a forma indeterminada da doença de Chagas. MÉTODOS: Doze pacientes com a forma indeterminada da doença de Chagas e 12 voluntários saudáveis foram avaliados. RESULTADOS: A pressão arterial basal e a frequência cardíaca foram semelhantes nos dois grupos. Os níveis plasmáticos de noradrenalina encontravam-se ligeiramente aumentados no grupo de pacientes chagásicos. Após o Teste de Tolerância a Insulina (TTI), houve um declínio significativo na glicose dos dois grupos. A Infusão de ILH resultou em aumento da pressão arterial em ambos os grupos, mas não houve nenhuma mudança significativa na noradrenalina plasmática. O componente de Baixa Frequência (BF) mostrou-se semelhante e aumentou de forma semelhante em ambos os grupos. O componente de Alta Frequência (AF) apresentou-se menor no grupo chagásico. CONCLUSÃO: Pacientes com forma indeterminada da doença de Chagas apresentaram aumento da atividade simpática no momento basal e uma resposta inadequada à insulina. Eles também tiveram um menor componente de alta frequência e sensibilidade barorreflexa prejudicada no momento basal e durante a infusão de intralipid e heparina.

BACKGROUND: Intralipid and heparin infusion results in increased blood pressure and autonomic abnormalities in normal and hypertensive individuals. OBJECTIVE: To evaluate insulin sensitivity and the impact of Intralipid and heparin (ILH) infusion on hemodynamic, metabolic, and autonomic response in patients with the indeterminate form of Chagas' disease. METHODS: Twelve patients with the indeterminate form of Chagas' disease and 12 healthy volunteers were evaluated. RESULTS: Baseline blood pressure and heart rate were similar in both groups. Plasma noradrenaline levels were slightly increased in the Chagas' group. After insulin tolerance testing (ITT), a significant decline was noted in glucose in both groups. ILH infusion resulted in increased blood pressure in both groups, but there was no significant change in plasma noradrenaline. The low-frequency component (LF) was similar and similarly increased in both groups. The high-frequency component (HF) was lower in the Chagas' group. CONCLUSION: Patients with the indeterminate form of Chagas' disease had increased sympathetic activity at baseline and impaired response to insulin. They also had a lower high-frequency component and impaired baroreflex sensitivity at baseline and during Intralipid and heparin infusion.

FUNDAMENTO: La Infusión de intralipid® y de heparina trae como resultado un aumento de la presión arterial y también de las anormalidades autonómicas en los individuos normales e hipertensos. OBJETIVO: Evaluar la sensibilidad a la insulina y el impacto de la infusión de intralipid® y de heparina (ILH) sobre la respuesta hemodinámica, metabólica y autonómica en pacientes con la forma indefinida de la Enfermedad de Chagas. MÉTODOS: Fueron evaluados doce pacientes con la forma indefinida de la Enfermedad de Chagas y 12 voluntarios sanos. RESULTADOS: La presión arterial basal y la frecuencia cardíaca fueron similares en los dos grupos. Los niveles plasmáticos de noradrenalina estaban ligeramente más elevados en el grupo de pacientes chagásicos. Después del Test de Tolerancia a la Insulina (TTI), se produjo una ostensible disminución en la glucosa de los dos grupos. La Infusión de ILH trajo como consecuencia el aumento de la presión arterial en ambos grupos, pero no hubo ningún cambio significativo en la noradrenalina plasmática. El componente de Baja Frecuencia (BF), fue similar y aumentó de forma parecida en ambos grupos. El componente de Alta Frecuencia (AF) se presentó con un menor nivel en el grupo chagásico. CONCLUSIONES: Los pacientes con una forma indeterminada de la Enfermedad de Chagas, presentaron un aumento en la actividad simpática al momento basal y una respuesta inadecuada a la insulina. También tuvieron un menor componente de alta frecuencia y de sensibilidad barorrefleja, que fue perjudicado en el momento basal y durante la infusión de intralipid® y heparina.

Efeitos de diferentes emulsoes lipidicas no tratamento de colite inflamatoria experimental em ratos / Effects of different lipidic emulsions in the treatment of experimental inflammatory colitis in rats

Lipides sao usados na nutricao parenteral e enteral, como fonte de acidos graxos essenciais e de energia. Diferentes tipos de lipides presentes na dieta podem induzir mudancas na estrutura da membrana celular, acarretando em modificacoes na sua funcao...

Hematologic disorders in trauma patients during parenteral alimentation with lipids

Total parenteral nutrition with lipids is a well-accepted modality of metabolic support in seriously ill trauma patients. Intolerance to lipid administration is unusual when dosage limits are not exceeded, and few hematologic disturbances have been recorded with modern fat emulsions. In the course of intravenous alimentation of six adults admitted for traumatic lesions, eosinophilia with or without leukocytopenia was noticed after periods of four days to five weeks. Principal clinical events and hematologic derangements were documented in this population. Sepsis was not always present in the patients by the time of the complication, and in those that did require antibiotics and other drugs, the prescription remained unchanged along the episode. Discontinuation of the nutritional regimen with lipids was followed by normalization of the hematologic profile, suggesting that an acute or sub-acute allergic reaction was responsible. The appearance of skin rash in two occasions reinforces this hypothesis, and the possibility of hemophagocytosis merits consideration in two of the cases who displayed reversible acute leukocytopenia. It is concluded that blood cell aberrations are possible during intravenous feeding with lipids in trauma subjects, but tend to respond to suppression of the lipid-containing nutritional prescription.

Radicales libres: bioquímica y sistemas antioxidantes: implicancia en la patología neonatal / Free radicals: biochemistry and antioxidants: their implication in newborn pathology

Los radicales libres del oxígeno se forman continuamente en el organismo por el metabolismo normal, siendo eliminados por las defensas antioxidantes. Cuando, son producidos en exceso pueden ocasionar una lesión tisular, por cuyo motivo han sido implicados en muchas enfermedades. En esta revisión se dan algunas nociones de la química de estos compuestos, se resume el mecanismo de su producción y el papel desempeñado por los iones de los metales de transición. Se insiste también sobre la importancia de la defensa antioxidante, cuya función es prevenir la oxidación, ya sea eliminando las especies reactivas del oxígeno tales como el radical superóxido, el radical hidroxilo o el peróxido de hidrógeno, o previniendo su formación. Los efectos deletéreos de estos compuestos se pueden observar en diversas patologías del adulto y del niño. El recién nacido, sobre todo pretérmino, es especialmente vulnerable, dado que nace con una protección insuficiente contra los radicales libres del oxígeno. En este sentido se analiza el papel desempeñado por los radicales libres en las siguientes afecciones: encefalopatía hipóxico-isquémica, enterocolitis necrotizante, broncodisplasia pulmonar, retinopatía del prematuro y hemorragia intraventricular. También se señala la importancia de la lipoperoxidación en la administración intravenosa de una emulsión de lípidos