[Emergency stiuations connected with electrolyte disorders. Special aspects]

Electrolyte-induced situations which are dangerous to life usually result from disturbances of the extracellular volume (ECV), osmolarity, the potassium level or the acid-base equilibrium. In recent years (thanks to the wide spread use of hormone therapy for mammary carcinoma) severe hypercalcemia has increased in importance as a life-threatening complication, while hypocalcemia, at least in adults, should only very seldom lead to unexpected emergencies. As long as serious clinical symptoms do not suggest an emergency, assessment of the threat to the patient as a result of the existing electrolyte disturbance often causes some difficulty. Besides the extent of the deviation from normal, the rate of development of the disturbance determines the resulting danger: chronic hypo-osmolarity, and especially hyperosmolarity are occasionally tolerated without symptoms while acute disturbances of the same or a less extent lead to severe central nervous symptoms. A similar state of affairs is also true of the emergency situations arising from disturbances of the acid-base equilibrium, among which the respiratory disorders are particularly important clinically. In the case of threatening disorders of the potassium metabolism, the accompanying circumstances (digitalis, simultaneous disorders and treatment of the acid-base equilibrium) often determine the clinical significance and danger to the patient. Clinical symptoms, anticipation ("expecting the unexpected"), prevention and treatment of emergency situations of fluid volume, osmolarity, potassium and acid-base equilibrium are the subjects of this paper.