Association between hypophosphatemia and cardiac arrhythmias in the early stages of sepsis

Background: The purpose of this study was to evaluate a possible association between serum phosphate levels and the incidence of cardiac arrhythmias in the early stages of sepsis. Methods: We conducted a prospective, controlled study in the General Intensive Care Unit (GICU) of a university hospital. Sixteen patients with sepsis, but without any previous cardiac disease, were studied during their first 24 h in the GICU. Patients were connected to a continuous ECG recording device. Blood samples for serum phosphate level determinations were drawn during the first 6 h after admission to the unit. Results: Ten of 16 patients had 21 episodes of atrial and ventricular arrhythmias. These patients had higher mean Apache II scores (20.2±6.2) than the six patients without arrhythmias (13.2±1.7; P<0.05) and significantly lower mean phosphate levels (0.73±0.16 vs. 1.02±0.32 mmol/l; P<0.03). No association was found between serum phosphate levels and mortality among patients with arrhythmias, or when all survivors (with and without arrhythmia) were compared to all non-survivors. Conclusions: The results indicate that patients with sepsis and low serum phosphate levels are at a greater risk of developing cardiac arrhythmias. We suggest that phosphate supplementation in the early stages of sepsis may prevent cardiac arrhythmias.