ALB and chronic obstructive pulmonary disease: The findings revealed a U-shaped relationship between ionized calcium and 28-day mortality in patients with sepsis, after adjusting for the following covariates: gender, age, BMI, ethnicity, temperature, respiratory rate, heart rate, MAP, PaO2, PaCO2, WBC, hemoglobin, total bilirubin, albumin, glucose, BUN, creatinine, sodium, potassium, chloride, dialysis, vasopressor, calcium gluconate/calcium chloride, septic shock, COPD, diabetes, hypertension, CHF, MI, CKD, cirrhosis, cancer, PE, stroke, site of infection, APACHE IV score and SOFA score.