The Role of the K/iCa Ratio in Predicting in Hospital Mortality in Patients with Upper Gastrointestinal Bleeding

Aim: Upper gastrointestinal bleeding (UGIB) is a common cause of emergency department presentation.Risk stratification of patients presenting to the emergency department with UGIB is important to predict active bleeding, need for blood transfusion, and mortality.In this study, we aimed to investigate the effect of potassium (K) and ionized calcium (iCa) on disease severity and mortality in UGIB patients.Materials and Methods: This is a retrospective, single-center study.Patients aged 18 years and older who presented to the emergency department with UGIB, underwent blood gas analysis within the first half hour of presentation to the emergency department, were admitted to the hospital by the gastroenterology department, underwent endoscopy, and had complete data records were included in the study. Results:The study included 699 patients.The in-hospital mortality rate was 7.7%.In the ROC analysis performed to determine the cut-off value of the K/iCa ratio for predicting mortality and active bleeding, the area under the curve values were 0.892 [95% confidence interval (CI): 0.845-0.939,p<0.001] and 0.832 (95% CI: 0.792-0.871,p<0.001), respectively.Patients were divided into 2 groups: those with a K/iCa ratio lower than 5.02 and those with a ratio higher than 5.02.This ratio has a high specificity value in terms of mortality prediction.Hemodynamic instability, active bleeding, need for erythrocyte suspension, length of hospital stay, and mortality were higher in the high K/iCa ratio group (p<0.001 for all values). Conclusion:In patients presenting to the emergency department with suspected UGIB, assessment of the K/iCa ratio using blood gas analysis may help to predict the risk of active bleeding and in-hospital mortality as a rapid, inexpensive, and practical assessment method.Patients with a high K/iCa ratio may be candidates for early endoscopy and closer hemodynamic monitoring.