Inflammation Indıces and Mortality in Adult Crush Syndrome

The Association of Systemic Inflammation-Based Hematological Indices With APACHE II, SOFA and 28-Day Mortality in Adult Crush Syndrome: A Retrospective Cohort Study

This single-center, retrospective observational cohort study evaluated the prognostic value of complete blood count-derived inflammatory indices - the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), systemic immune-inflammation index (SII), systemic inflammatory response index (SIRI), and pan-immune-inflammation value (PIV) - for the prediction of 28-day mortality in adult patients with crush syndrome admitted to the intensive care unit (ICU).

Consecutive patients aged 18 years and older who were diagnosed with crush syndrome and admitted to the ICU between January 1, 2018, and September 30, 2025, were included. All indices were calculated from the complete blood count obtained within the first 24 hours of ICU admission. The primary and only outcome was 28-day mortality. The discrimination and independent prognostic value of the inflammatory indices were compared with the APACHE II and SOFA scores, and their incremental value beyond these established severity scores was assessed.

Study Overview

• Status: Completed
• Conditions: Critical Illness; Rhabdomyolysis; Systemic Inflammatory Response; Crush Syndrome

Detailed Description

Crush syndrome is a life-threatening consequence of traumatic rhabdomyolysis, characterized by a systemic inflammatory response, acute kidney injury, electrolyte disturbances, and multi-organ dysfunction, with the highest mortality observed among patients requiring intensive care. Early and objective risk stratification is essential for guiding fluid resuscitation, informing the timing of renal replacement therapy, and allocating critical care resources.

In this single-center, retrospective cohort study, adult patients (≥18 years) diagnosed with crush syndrome and admitted to the intensive care unit of Ataturk University Research Hospital between January 1, 2018, and September 30, 2025, were identified from the hospital electronic health information system. The diagnosis was based on a compatible history of crush injury together with a serum creatine kinase level exceeding five times the upper limit of normal. Patients with conditions that directly alter hematological indices - hematological malignancy, active chemotherapy, chronic immunosuppressive therapy, massive transfusion within the first 24 hours, or known thrombocytopenia - were excluded. Demographic data, complete blood count parameters, and disease-severity scores were retrieved from electronic medical records.

The following inflammatory indices were calculated from the complete blood count obtained within the first 24 hours of ICU admission: NLR (neutrophils/lymphocytes), PLR (platelets/lymphocytes), MLR (monocytes/lymphocytes), SII (platelets × neutrophils/lymphocytes), SIRI (neutrophils × monocytes/lymphocytes), and PIV (neutrophils × platelets × monocytes/lymphocytes).

The primary and only endpoint was 28-day mortality following ICU admission. Group comparisons were performed using the Mann-Whitney U and Student t tests. Discrimination for 28-day mortality was assessed by receiver operating characteristic (ROC) curve analysis, and the areas under the curve were compared with the DeLong test. Because the six indices are deterministic ratios of four blood-count components and are therefore highly collinear, each index was entered into a separate logistic regression model together with the APACHE II and SOFA scores, rather than including all indices in a single model. The incremental discriminatory value of each index beyond an APACHE II plus SOFA base model was quantified as the change in the area under the curve, and internal validity was examined by bootstrapping. The study aimed to determine whether these readily available hematological indices provide prognostic value beyond established severity scores in critically ill patients with crush syndrome.

• Study Type: Observational
• Enrollment (Actual): 325

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Erzurum, Turkey (Türkiye), 20100
    • Ataturk University Research Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Adult patients diagnosed with crush syndrome and admitted to the intensive care unit of Ataturk University Hospital between January 2018 and September 2025.

Description

Inclusion Criteria:

• Age ≥18 years
• Diagnosis of crush syndrome based on clinical and laboratory findings
• Admission to the intensive care unit (ICU) between January 1, 2018 and September 30, 2025
• Availability of complete blood count parameters within the first 24 hours of ICU admission

Exclusion Criteria:

• Age <18 years
• Incomplete medical records
• Missing laboratory data required for calculation of inflammatory indices
• Patients discharged or transferred within 24 hours of ICU admission

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
28-day All-Cause Mortality	All-cause mortality within 28 days of intensive care unit (ICU) admission in adult patients with crush syndrome.	28 days from ICU admission

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ICU Mortality	Death occurring during the intensive care unit stay.	During ICU stay (up to 28 days)
In-Hospital Mortality	All-cause mortality occurring during the index hospital admission.	During hospital stay (up to 90 days)

Collaborators and Investigators

• Sponsor: Ataturk University

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2018
• Primary Completion (Actual): October 28, 2025
• Study Completion (Actual): October 28, 2025

Study Registration Dates

• First Submitted: February 19, 2026
• First Submitted That Met QC Criteria: February 19, 2026
• First Posted (Actual): February 25, 2026

Study Record Updates

• Last Update Posted (Actual): August 18, 2026
• Last Update Submitted That Met QC Criteria: August 15, 2026
• Last Verified: August 1, 2026

More Information

Terms related to this study

• Keywords: Intensive Care Unit; MLR; PLR; NLR; APACHE II; PIV; Neutrophil-to-Lymphocyte Ratio; SOFA SCORE; SIRI; SII; Platelet-to-Lymphocyte Ratio; Monocyte-to-Lymphocyte Ratio; Systemic Immune-Inflammation Index; Systemic Inflammatory Response Index; Pan-Immune-Inflammation Value; 28-day Mortality
• Additional Relevant MeSH Terms: Crush Injuries; Musculoskeletal Diseases; Muscular Diseases; Wounds and Injuries; Pathologic Processes; Disease Attributes; Shock, Traumatic; Pathological Conditions, Signs and Symptoms; Critical Illness; Rhabdomyolysis; Crush Syndrome
• Other Study ID Numbers: B.30.2.ATA.0.01.00/756

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No