Zusammenfassung
Störungen des Kaliumhaushalts sind perioperativ und beim Intensivpatienten häufig
anzutreffen – sie können sich schnell zu einer akuten Lebensbedrohung entwickeln.
Dieser Beitrag geht auf die physiologischen Grundlagen des Kaliumhaushalts ein und
zeigt auf, wie akute Störungen behandelt werden können.
Abstract
Potassium is a key cation in the human organism and largely responsible for the resting
membrane potential of excitable cells. 98% of the potassium pool resides within the
cells and only 2% in the extracellular space. Thus, blood sample measurements of potassium
do not necessarily reflect the total potassium state. The extracellular potassium
concentration however is tightly regulated, either through potassium elimination via
the kidney or shift between the intra- or extracellular compartment. Changes in the
blood serum potassium concentration are defined as hypokalemia (< 3,5 mmol/l) or hyperkalemia
(> 5,0 mmol/l). Hypokalemia is caused by a low-potassium diet, gastrointestinal losses
or polyuric renal failure. Hyperkalemia can follow excessive intake, severe tissue
damage or oliguric or anuric renal failure. Acute alteration of the extracellular
potassium concentration should spark immediate action by the perioperative physician.
In particular, hyperkalemic states require immediate attention and therapeutic interventions.
In this review, we give an overview of the pathophysiology of potassium changes and
provide a practical approach to their management.
Schlüsselwörter
Kalium - Pathophysiologie - Hyperkaliämie - Hypokaliämie - Elektrolytstörungen
Key words
Potassium - pathophysiology - hypokalemia - hyperkalemia
