Potassium Disorders and the Risk of Cardiac Arrhythmia in Older Persons Undergoing Common Non-Cardiac Surgical Procedures

Background: Electrolyte disorders are risk factors for perioperative outcomes and studies have suggested potassium disorders are risk factors for perioperative cardiac arrhythmia in cardiac surgery. Little is known about the association between potassium disorders and cardiac arrhythmia among patients having non-cardiac surgery. This study assessed the association between hypokalemia and hyperkalemia and cardiac arrhythmia in older adults having common non-cardiac surgical procedures. Methods: Using the State Inpatient Databases for New Jersey, Maryland, and Arizona, we studied persons age 65+ who had common non-surgical procedures in three broad categories: orthopedic vascular and abdominal (n=64,628). The outcome of interest was cardiac arrhythmia and exposures were hypokalemia and hyperkalemia. Analyses included descriptive statistics and multivariate logistic regression, which adjusted for demographic characteristics, and comorbidities. Results: Hypokalemia was present in 6.0% of the sample. Hperkalaemia was present in 1.3%. Of all the procedures, orthopedic were 70.5%, abdominal, 15.2%, vascular 14.35%. Adjusted models assessing factors associated with hyperkalemia and hypokalemia showed urban residents had higher odds of having hyperkalemia (Odds Ratio 1.67, 95% Confidence Interval 1.21-2.32) and hypokalemia (1.24, 1.08-1.42). Other risk factors were dehydration, hypovolemia, and increasing age. Both hypokalemia (1.12, 1.03-1.22) and hperkalemia (1.19, 1.01-1.41) were risk factors for cardiac arrhythmia and individuals having procedure associated with higher risk of hypokalemia also had higher risk of cardiac arrhythmia. Conclusions: Results suggest that potassium disorders may increase the risk of cardiac arrhythmia in older adults having non-cardiac surgical procedures. Findings underscore the need to monitor potassium levels among older patients undergoing non-cardiac surgical procedures.