Calcium for resuscitation?

Abstract

Calcium ions are essential for myocardial excitation-contraction coupling and for increasing contractility of the heart. Because of these physiological effects, use of calcium has been recommended in the treatment of electromechanical dissociation, asystole and ventricular fibrillation. Recently, however, the use of calcium during cardiac arrest has come into dispute, as there are no controlled clinical trials supporting a favourable haemodynamic effect. It has rather been suggested that, in resuscitation, calcium may have detrimental effects. In order to evaluate the role of calcium in cardiopulmonary resuscitation, it is important to know the serum concentrations of calcium and the haemodynamic effects in this situation. Measurements in some patients with cardiac arrest have demonstrated that severe hypocalcaemia may not be uncommon. In these patients, calcium may augment myocardial contractility, decrease intracardiac filling pressures and increase mean arterial pressure. At present, the more or less established indications for use of calcium during cardiopulmonary resuscitation are in treating patients with proven hypocalcaemia, hyperkalaemia, calcium channel blocker overdose and, possibly, electromechanical dissociation combined with a wide QRS complex. There is no good evidence supporting the routine use of calcium in resuscitation.