Managing Syncope in Smaller Setting

With all the variety of individual phenotypic adaptation, its development in higher animals is characterized by certain common features. There are two stages in the development of most adaptive reactions, namely: the initial stage of urgent but imperfect adaptation and the subsequent stage of perfect, long-term adaptation. The urgent stage of the adaptive reaction occurs immediately after the onset of the stimulus and, therefore, can be realized only on the basis of ready-made, previously formed physiological mechanisms. The obvious manifestations of urgent adaptation are the animal's flight in response to pain, an increase in heat production in response to cold, an increase in heat transfer in response to heat, an increase in pulmonary ventilation and minute volume of blood circulation in response to lack of oxygen. The most important feature of this stage of adaptation is that the body's activity proceeds at the limit of its physiological capabilities — with almost complete mobilization of the functional reserve — and does not fully provide the necessary adaptive effect. Thus, running of an unadapted animal or human occurs at near-maximum values of the minute volume of the heart and pulmonary ventilation, with maximum mobilization of the glycogen reserve in the liver; due to insufficiently rapid oxidation of pyruvate in muscle mitochondria, the level of lactate in the blood increases. This lacedemia limits the intensity of the load — the motor reaction can be neither fast enough nor long enough. Thus, adaptation is implemented "from the spot", but it turns out to be imperfect.