Retrospective evaluation of the neutrophil-to-lymphocyte ratio as a prognostic marker in cats with blunt trauma (2018–2021): 177 cases

Objective

To investigate the utility of the neutrophil-to-lymphocyte ratio (NLR) as a prognostic marker in cats with blunt trauma.

Design

Retrospective study from January 2018 to December 2021.

Setting

University teaching hospital.

Animals

Medical records of 177 cats admitted with blunt trauma were evaluated. History, clinical findings, blood cell count-based ratios, thoracic radiographs on presentation, and outcome were reviewed. The Animal Trauma Triage (ATT) score was assessed in each cat and classified as mild (1–3), moderate (4–7), and severe trauma (≥8). Forty-eight healthy blood donor cats served as the control population. NLR, neutrophil counts, and lymphocyte counts were compared between cats with blunt trauma and controls, and among trauma patients.

Interventions

None

Measurements and Main Results

NLR, neutrophil counts, and lymphocyte counts significantly differ in cats with blunt trauma compared to controls (p < 0.001), and NLR was higher in patients with thoracic trauma (p = 0.044). Nonsurvivors had lower lymphocyte counts (p = 0.041), although those values do not appear to be clinically relevant. A significant increase in NLR was observed with increasing severity of trauma (p < 0.001). The NLR was not associated with the length of hospitalization, intensive care assistance, or mortality.

Conclusion

NLR is a widely available diagnostic tool, which can be used in addition to ATT to assess trauma severity, although in our study it was not predictive of the outcome.