Murat ÇAP, Ferhat IŞIK, Önder BİLGE, Bernas ALTINTAŞ, Abdurrahman AKYÜZ, Burhan ARSLAN, Ümit İNCİ, Rojhat ALTINDAĞ, İlyas KAYA, Flora OZKALAYCI, İbrahim Halil TANBOĞA, Kemal GÜNEŞ

Serum Ionized Calcium Levels May Be More Closely Related To The Admission Qtc Interval Than Total Calcium Levels In Patients Hospitalized With Covid-19

Hypocalcemia prolongs the QTc interval. Total calcium (TCa) measurement can be misleading in cases where theconcentration of albumin is abnormal. We aimed to investigate which calcium level—ionized calcium (iCa) or TCa—maybe more closely related to the QTc interval in COVID-19 patients in whom hypocalcemia and hypoalbuminemia areobserved frequently.Adult patients hospitalized for COVID-19 were included in this study. ICa levels were obtained from the venous blood gassample examined during the emergency department admission, and the TCa levels were obtained from the biochemistryresults on admission. The pH-adjusted iCa (Corrected-iCa) and albumin-adjusted TCa (corrected-TCa) were calculated. TheQT interval was measured from the admission ECG and corrected for heart rate using the Bazett formula.Hundred and thirty-two patients were included in the study. The mean age was 50±19 years, and 62 (47%) patients werefemale. Median iCa level was 1,13 mmol/L (1,08-1,18 interquartile range (IQR)), median TCa level was 2.13 mmol/L (2.02 -2.22 IQR). 76 patients (57%) had hypocalcemia (iCa

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