RESUMEN
OBJECTIVE: Intravenous infusion of crystalloid solutions is a cornerstone of the treatment of hemorrhagic shock. However, crystalloid solutions can have variable metabolic acid-base effects, perpetuating or even aggravating shock-induced metabolic acidosis. The aim of this study was to compare, in a controlled volume-driven porcine model of hemorrhagic shock, the effects of three different crystalloid solutions on the hemodynamics and acid-base balance. METHODS: Controlled hemorrhagic shock (40 percent of the total blood volume was removed) was induced in 18 animals, which were then treated with normal saline (0.9 percent NaCl), Lactated Ringer's Solution or Plasma-Lyte pH 7.4, in a blinded fashion (n = 6 for each group). Using a predefined protocol, the animals received three times the volume of blood removed. RESULTS: The three different crystalloid infusions were equally capable of reversing the hemorrhage-induced low cardiac output and anuria. The Lactated Ringer's Solution and Plasma-Lyte pH 7.4 infusions resulted in an increased standard base excess and a decreased serum chloride level, whereas treatment with normal saline resulted in a decreased standard base excess and an increased serum chloride level. The Plasma-Lyte pH 7.4 infusions did not change the level of the unmeasured anions. CONCLUSION: Although the three tested crystalloid solutions were equally able to attenuate the hemodynamic and tissue perfusion disturbances, only the normal saline induced hyperchloremia and metabolic acidosis.
Asunto(s)
Animales , Masculino , Equilibrio Ácido-Base/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Soluciones Isotónicas/efectos adversos , Choque Hemorrágico/tratamiento farmacológico , Modelos Animales de Enfermedad , Métodos Epidemiológicos , Gluconatos/efectos adversos , Concentración de Iones de Hidrógeno , Soluciones Isotónicas/clasificación , Cloruro de Magnesio/efectos adversos , Cloruro de Potasio/efectos adversos , Porcinos , Choque Hemorrágico/inducido químicamente , Acetato de Sodio/efectos adversos , Cloruro de Sodio/efectos adversosRESUMEN
Hipovolemia em pacientes agudamente enfermos é um evento relativamente comum, e com importância clínica para o paciente, sendo a rápida e vigorosa reposição volêmica capaz de diminuir o risco de morte inicialmente e de evolução para falência renal na sequência. Neste artigo revisaremos os diferentes tipos de expansores, suas propriedades, vantagens e desvantagens. Os cristaloides se mantêm como preferência pela segurança, eficácia e baixo custo, com a desvantagem da importante formação de edema. As soluções hipertônicas têm indicação no atendimento pré-hospitalar por ser eficaz, porém com estabilização hemodinâmica de caráter efêmero, e pela possibilidade de distúrbios eletrolíticos. Estudos clínicos randomizados não demonstraram superioridade da albumina aos cristalóides e assim como são de custo alto ficam como segunda alternativa ou casos selecionados.
Hypovolemia in critically ill patients is a common event in intensive care patients, and it is clinically relevant for the patient. The fluid replacement is used to try to reduce risk of death and evolution to renal failure. In this article we review different types of expansors, their properties, advantages and disadvantages. Crystalloids are indicated for the safety, efficacy and low cost, the only disadvantage is oedema formation. Hypertonic crystalloid are indicated only in prehospitalar fluid resuscitation, because of your efficacy, but for a short period of time, and the possibility of hydroeletrolitic derangements. There is no evidence that colloids are more effective than crystalloids in reducing mortality in people who are critically ill or injured, and the high cost, turn them the second choice.