[Changes in the plasma magnesium content in patients subjected to cardiopulmonary bypass]

Changes in plasma magnesium content in 17 patients operated in extracorporeal circulation are reported. Values were low at the end of the operation, but rose at the end of the first day to achieve spontaneous resolution of the condition within 3 days. No close relationship between such loss and immediate postoperative arrhythmia could be discerned. Attention is, however, drawn to 3 cases in which ventricular fibrillation was not resolved until electric shock treatment was preceded by the administration of magnesium sulphate.