Prognostic Value of Systemic Immune-Inflammatory and Nutritional Indices for Mortality and Morbidity in Acute Aortic Dissection: A Single-Center Retrospective Study

This is a single-center observational study based on a retrospective review of the records of patients who underwent surgical treatment for acute aortic dissection at the Bursa City Hospital Operating Room between January 1, 2022, and March 1, 2026. The study was planned and conducted in accordance with the principles of the Declaration of Helsinki and was approved by the Bursa City Hospital Scientific Research Ethics Committee (Decision No: 2026-12/9).

A total of 127 adult patients who underwent surgical treatment with a diagnosis of acute aortic dissection during the specified period were included in the study. The diagnosis was confirmed through clinical findings and radiological examinations, primarily computed tomography angiography, and the type of dissection was recorded. Inclusion criteria: being 18 years of age or older and having undergone surgical intervention for acute aortic dissection. Patients meeting the following criteria were excluded from the study: those with a diagnosis of chronic aortic dissection; cases with missing preoperative laboratory data or clinical outcome records; patients with hematological malignancies or disorders such as leukemia, lymphoma, or immune thrombocytopenic purpura (ITP); those with chronic inflammatory or autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus (SLE), or ankylosing spondylitis; patients with active steroid use, immunosuppressive therapy, or recent chemotherapy; and those diagnosed with decompensated liver failure or end-stage renal disease (ESRD). These exclusion criteria were established to ensure the reliability of the results by eliminating patients with comorbidities or treatments that could directly affect neutrophil, platelet, and lymphocyte counts-the study's primary independent variables.

All data were obtained from the hospital's electronic information system and patient files. Age, gender, dissection type, and left ventricular ejection fraction were recorded as demographic and clinical variables. Preoperative blood values were recorded prior to the surgical intervention. The preoperative laboratory parameters examined included white blood cell (WBC) count, neutrophil, lymphocyte, and platelet counts, hemoglobin, D-dimer, creatine kinase-MB (CK-MB), troponin, creatinine, estimated glomerular filtration rate (eGFR), albumin, and C-reactive protein (CRP) levels. Lactate, partial pressure of carbon dioxide (pCO2), and partial pressure of oxygen (pO2) values were obtained from preoperative arterial blood gas analysis. In surviving patients, postoperative values for the same markers were also calculated.

The composite markers investigated were calculated for each patient using the following formulas based on preoperative laboratory values:

Systemic Immune-Inflammation Index (SII): (neutrophil count × platelet count) / lymphocyte count Neutrophil-to-Lymphocyte Ratio (NLR): neutrophil count / lymphocyte count Platelet-to-Lymphocyte Ratio (PLR): platelet count / lymphocyte count CRP-to-Albumin Ratio (CAR): CRP / albumin Prognostic Nutritional Index (PNI): (10 × serum albumin [g/dL]) + (0.005 × total lymphocyte count [/mm3]) SII × Lactate Composite Index: SII × preoperative arterial lactate (mmol/L) The SII × Lactate composite index was defined to combine systemic inflammatory load (SII) and tissue hypoperfusion/anaerobic metabolism (lactate) into a single value. In surviving patients, postoperative values of SII, NLR, PLR, CAR, and PNI were also calculated using the same formulas and compared with preoperative values.