Wide QRS complex as a predictor of hyperkalemia during pulseless electrical activity (PEA) cardiac arrest = Wide QRS complex as a predictor of hyperkalemia during pulseless electrical activity (PEA) cardiac arrest

다국어 초록 (Multilingual Abstract)

Introduction
The aim of this study was to evaluate the association between hyperkalemia and the QRS widening in cardiac arrest patients showing initial electrocardiogram (ECG) rhythm of pulseless electrical activity (PEA).
Material & Method
This was a retrospective observational study of patients whose initial ECG rhythm was PEA among patients treated for cardiac arrest at a tertiary referral hospital. We reviewed the cardiac arrest registry which has been prospectively collected for cardiopulmonary resuscitation (CPR) quality improvement in our hospital. Out-of-hospital cardiac arrest (OHCA) and in-hospital cardiac arrest (IHCA) patients over the age of 18 were included in this study, and those with no measured potassium levels, no ECG rhythm strip records, or inability to clarify readings were excluded. The QRS interval of electrocardiogram in cardiac arrest patients was measured separately by two emergency physicians if the two physicians agreed, the initial rhythm was considered as wide QRS PEA.
Result
111 episodes in the wide QRS complex group and 506 episodes in the narrow QRS complex group were included. The wide QRS group showed significantly more diabetes patients, lower blood pH and higher creatinine than the narrow QRS group. The potassium level in the wide QRS group was significantly higher than in the narrow QRS group (5.4 mmol/L [IQR, 4.4-6.7] vs. 4.6 mmol/L [IQR, 4.0-5.6] p<0.001). This trend remained in similar trends regardless of the presence of CKD or dialysis. In patients who were unable to excrete potassium well due to poor renal function, probability of having hyperkalemia at the time of PEA cardiac arrest was significantly higher in the wide QRS group than in the narrow QRS group.
Conclusion
The width of the QRS complex showed a significant correlation with the serum potassium level. In the presence of kidney dysfunction, wide QRS complex tended to have a stronger association with hyperkalemia. To better evaluate the effectiveness of these treatments in the clinical setting, a larger scale multicenter trials is needed.