Golpe de calor / Heatstroke

El golpe de calor es una situación en la que una persona sometida a altas temperaturas ambientales experimenta un fracaso, potencialmente letal, del sistema de termorregulación corporal. Se trata de una patología infradiagnosticada, de baja prevalencia, pero con elevada morbimortalidad, cuya incidencia ha aumentado en los últimos años y seguramente seguirá aumentando, debido a la frecuencia cada vez mayor de las olas de calor vinculadas al cambio climático, producto del calentamiento global. Su presentación clínica se caracteriza por temperaturas corporales por encima de los 40º C y disfunción orgánica múltiple que, si no se tratan de manera rápida y adecuada, conducen a la muerte. Los pilares de su tratamiento son el sostén de las funciones en falla y la disminución inmediata de la temperatura central.(AU)

Heat stroke is a situation where a person subject to high temperatures experiences the failure of the body thermoregulation system, a potentially lethal condition. This is an underdiagnosed disease, with low prevalence, but a high mortality, whose incidence has increased in recent years and will surely continue to rise due to the increasing frequency of heat waves linked to climate change, as a result of global warming. Its clinical presentation is characterized by body temperature >40º C and multiple organ dysfunction leading to death, if the patient does not receive prompt and appropriate treatment. The mainstays of treatment are function support and the immediate drop in core temperature.(AU)

[Study of the relaxation phase of the right ventricle]. / Estudio de la fase de relajación del ventrículo derecho.

The purpose of our study was to investigate the existence or not of an isovolumic relaxation period in the right ventricle in experimental animals with normal pressures in the pulmonary artery. Right and left ventricular pressures, pulmonary and aortic pressures (microtransducers), pulmonary flow, ventricular diameters (sonomicrometer), were recorded at the same time, in 10 sheep anesthetized intravenously with pentobarbital. We obtained "off line" the first ventricular pressures derivative, the ventricular volumes and the pressure-volume loops of both ventricles. The minimum systolic right ventricular volume coincided with 0 pulmonary flow, and both with a diastolic pressure value of 0-5 mmHg in that ventricle. Once the minimum systolic volume was reached, a rapid increase of the right ventricular volume started. The right ventricular pressure-volume loop, unlike the left ventricular one, adopted a non-rectangular shape. The right ventricular ejection period lasted until the beginning of the next filling phase. We concluded that there is no right ventricular isovolumic relaxation period.

[The characteristics proper of the cardiac cycle phases of the right ventricle]. / Características propias de las fases del ciclo cardíaco del ventrículo derecho.

AIMS: The purpose of our study was to define at physiological conditions, the existence or not of an isovolumic relaxation phase in the right ventricle and its ejective phase properties. MATERIAL AND METHODS: Right and left ventricular pressures, pulmonary and aortic pressures, pulmonary flow and ventricular diameters by sonomicrometry were measured in nine anesthetized sheep. The first ventricular pressure derivative, ventricular volumes, and the right and left pressure-volume loops, were calculated "off line". An abrupt preload reduction was generated by a posterior vena caval occlusion. RESULTS: Right ventricle showed an ejection phase which can be subdivided in two phases (early and late). The end of the ejection phase was established by the temporal coincidence of the zero pulmonary flow, the minimum systolic value of the right ventricular volume and a right ventricular pressure of 0-4 mmHg. The time between the beginning of the ejection phase and: a) the end of systole; b) the negative peak of the first derivative of ventricular pressure and c) the end of ejection, were different for the right ventricle (67 +/- 15 ms, 274 +/- 30 ms, 412 +/- 33 ms, respectively), meanwhile the left ventricle showed the following values: 204 +/- 33 ms, 262 +/- 23 ms, 266 +/- 24 ms, respectively. CONCLUSIONS: Right ventricle exhibits a long lasting ejection phase which can be subdivided in two phases, spreading at the beginning of the next filling phase. This fact allows us to affirm that right ventricle does not show an isovolumic relaxation phase in comparison to left ventricle.

Use of spectrocolorimetry for study of lipid consumption by Trichothecium roseum.

Studies were carried out by means of spectrocolorimetry in order to determine the consumption of total lipids in cultures of Trichothecium roseum. This technique has the advantage of requiring very little specimen preparation.