Although
hypokalemia has been reported after
cardiac arrest and successful
resuscitation, experimental data indicate that
potassium is released from cells during
ischemia. The purpose of this investigation was to study serum
potassium concentration ([K+]) during closed chest
cardiopulmonary resuscitation (CC-
CPR) in humans. Twenty-two patients presenting to the emergency department (ED) in
cardiopulmonary arrest had simultaneous measurement of central venous and arterial [K+] and blood
gases during CC-
CPR utilizing current
advanced cardiac life support protocols and a pneumatic chest compressor and
ventilator. Mean arterial and central venous [K+] were 5.0 +/- 1.3 and 5.6 +/- 2.9 mEq/L, respectively, (p greater than .05) with 7 patients having [K+] of greater than 6 mEq/L. Significant
hyperkalemia does occur in some patients during
cardiac arrest and CC-
CPR. Because poor tissue perfusion during CC-
CPR impairs exchange between the interstitial and intravascular compartments, increases in interstitial [K+] would be expected to be even greater. Interstitial
hyperkalemia may play a role in the genesis of wide complex electromechanical dissociation (EMD) seen after prolonged
cardiac arrest. Since
calcium has long been known to be beneficial in the treatment of
hyperkalemia-induced dysrhythmias, the success of
calcium chloride in treating wide complex EMD may be on the basis of this phenomenon.