The effect of endotracheal aspiration on QT interval in intensive care unit patients

Objective: The intensive care unit (ICU) environment and applied methods may lead to a significant stimulation of sympathoadrenal activity. There are studies about the direct connection between increased plasma catecholamine levels during sympathetic activation and QT interval. Therefore, the aim of this study is to determine the effects of endotracheal aspiration on QT interval and QT dispersion. Method: 90 patients connected to a mechanical ventilator from the ages of 30-70 in ICU were taken into study. Patients taking any drug that prolongs QT, patients with unstable hemodynamia and congenital QT prolongation were excluded. Preoxygenation was done to all patients with 100% O2 administration for 1 minute before the endotracheal aspiration (ET). Age, diagnosis, weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR), peripheral oxygen saturation (SpO2), QT, QTc, Glasgow Coma Score (GCS) values were recorded before, during, 5 minutes after and 10 minutes after the ET aspiration. Results: During ET aspiration, the mean QTc value was 445.1±23.0 milliseconds (ms), the mean QT value was 379.2±19.3 ms. In 14% of the patients included in the study, basal QTc values above 420 ms were found to be prolonged. According to basal values, QT and QTc intervals were prolonged in almost all patients during, 5 minutes after and 10 minutes after the ET aspiration. Conclusions: QT interval prolongation should always be checked by calculating corrected QT interval, and ICU physicians need to be more careful in patients with coronary heart disease and congenital prolonged QT interval in terms of fatal ventricular arrhythmias