Computer-guided normal-low versus normal-high potassium control after cardiac surgery: No impact on atrial fibrillation or atrial flutter

• Published in: The American heart journal 2016-02, Vol.172, p.45-52
• Main Authors: Hoekstra, Miriam, MD, Hessels, Lara, Rienstra, Michiel, MD, PhD, Yeh, Lu, MD, Lansink, Annemieke Oude, MD, Vogelzang, Mathijs, MD, PhD, van der Horst, Iwan C.C., MD, PhD, van der Maaten, Joost M.A.A., MD, Mariani, Massimo A., MD, PhD, de Smet, Anne Marie G.A., MD, PhD, Struys, Michel M.R.F., MD, PhD, Zijlstra, Felix, MD, PhD, Nijsten, Maarten W., MD, PhD
• Format: Article
• Language: English
• Subjects: Aged; Algorithms; Atrial Fibrillation - epidemiology; Atrial Fibrillation - prevention & control; Atrial Flutter - epidemiology; Atrial Flutter - prevention & control; Cardiac arrhythmia; Cardiac Surgical Procedures; Cardiovascular; Double-Blind Method; Drug Monitoring - methods; Electrocardiography; Female; Follow-Up Studies; Glucose; Heart attacks; Heart Diseases - blood; Heart Diseases - surgery; Heart surgery; Hospitals; Humans; Incidence; Intensive care; Laboratories; Male; Mortality; Netherlands - epidemiology; Patients; Physiology; Postoperative Care - methods; Potassium; Potassium - administration & dosage; Potassium - pharmacokinetics; Prospective Studies; Radiometers
• ISSN: 0002-8703; 1097-6744
• DOI: 10.1016/j.ahj.2015.10.020

Introduction This study was designed to determine the effect of 2 different potassium regulation strategies with different targets (within the reference range) on atrial fibrillation (AF) or atrial flutter (AFL) in a cohort of intensive care unit patients after cardiac surgery. Methods The GRIP-COMPASS study was a prospective double-blinded interventional study in 910 patients after cardiac surgery (coronary artery bypass grafting and/or valvular surgery). Patients were assigned to either the normal-low potassium target (nLP group, 4.0 mmol/L) or the normal-high potassium target (nHP group, 4.5 mmol/L) in alternating blocks of 50 patients. Potassium levels were regulated using a validated computer-assisted potassium replacement protocol (GRIP-II). The primary end point was the incidence of AF/AFL on a 12-lead electrocardiogram during the first postoperative week. Results Of the 910 patients, 447 were assigned to the nLP group; and 463, to the nHP group, with no baseline differences between the 2 groups. The mean daily administered dose of potassium was 30 ± 23 mmol (nLP) versus 52 ± 27 mmol (nHP) ( P < .001), which resulted in mean intensive care unit potassium concentration of 4.22 ± 0.36 mmol/L and 4.33 ± 0.34 mmol/L, respectively ( P < .001). The incidence of AF/AFL after cardiac surgery did not differ: 38% in the nLP group and 41% in the nHP group. Also in several subgroups (eg, patients not known with prior AF/AFL or with valve surgery), there were no differences. Conclusions There were no differences in incidence of AF/AFL with 2 potassium regulation strategies with different potassium targets and different amounts of potassium administered in patients after cardiac surgery.