IL6 and chronic obstructive pulmonary disease: AKI: acute kidney injury; BNP: B-type natriuretic peptide; CAD: coronary artery disease; CKD: chronic kidney disease; CK-MB: creatine kinase MB; CLD: chronic liver disease; COPD: chronic obstructive pulmonary disease; CRP: C-reactive protein; CVA: cerebral vascular accident; DM: diabetes mellitus; HD: hemodialysis; HTN: hypertension; ICU: intensive care unit; IL-6: interleukin-6; LDH: lactate dehydrogenase; NIV: non-invasive ventilation; NRBM: non-rebreather mask; Trop I: troponin I