Impact of comorbidities in severely injured patients with blunt chest injury: A population-based retrospective cohort study.

INTRODUCTION: Blunt chest injuries result in up to 10 % of major trauma admissions. Comorbidities can complicate recovery and increase the mortality rate in this patient cohort. A better understanding of the association between comorbidities and patient outcomes will facilitate enhanced models of care for particularly vulnerable groups of patients, such as older adults.

AIMS: i) compare the characteristics of severely injured patients with blunt chest injury with and without comorbidities and ii) examine the relationship between comorbidities and key patient outcomes: prolonged length of stay, re-admission within 28 days, and mortality within 30 days in a cohort of patients with blunt chest injury admitted after severe trauma.

METHODS: A retrospective cohort study using linked data from the NSW Trauma Registry and NSW mortality and hospitalisation records between 1st of January 2012 and 31st of December 2019.

RESULTS: After adjusting for potential confounding factors, patients with severe injuries, chest injuries, and comorbidities were found to have a 34 % increased likelihood of having a prolonged length of stay (OR = 1.34, 95 %I = 1.17-1.53) compared to patients with no comorbidities. There was no difference in 30-day mortality for patients with a severe chest injury who did or did not have comorbidities (OR = 1.05, 95 %CI = 0.80-1.39). No significant association was found between comorbidities and re-admission within 28 days.

CONCLUSION: Severely injured patients with blunt chest injury and comorbidities are at risk of prolonged length of stay.