Ventilator-Associated Pneumonia in Trauma Patients with Splenic Injuries. Does Splenectomy Increase the Risk?

Author(s):
Michael Alchaer; Ricardo Fonseca; Leonardo Diaz; Hussain Afzal; Melissa Canas; Jason Snyder; Grant Bochicchio

Background:

There continues to be debate regarding whether splenectomy impacts the immune system is such a way that patients are at greater risk for infection. It is well-recognized that severely ill trauma patients are at significant risk for ventilator-associated pneumonia (VAP).

Hypothesis:

Our hypothesis is that severely injured trauma patients who undergo splenectomy as compared to splenic preservation do not have a greater incidence of VAP.

Methods:

A retrospective analysis of our acute and critical care surgery database selecting for all trauma patients with splenic injuries admitted from 2017 to 2023 was performed. We excluded all patients that expired within 48 hours of admission, had an injury severity score (ISS) <25 and had less than 3 ventilator days. We only included patients that were admitted to the surgical ICU with confirmed splenic injuries. The American Association for the Surgery of Trauma (AAST) splenic injury scale was used to define splenic injury. The National Trauma Data Standard developed by the American College of Surgeons of 2024 was used to define VAP. ISS, abbreviated injury scale (chest, abdomen/pelvis and head), demographics, length of stay (LOS), ICU LOS, ventilator days, mode of injury (MOI), microbiology result, vaccination status, and splenic laceration grading were analyzed. Patients were stratified by whether they underwent a splenectomy versus a splenic preservation procedure and subsequently followed for the diagnosis of VAP. Splenic preservation included embolization, splenorrhaphy and observation alone.

Results:

Of 140 patients who were evaluated, 64 (46%) underwent splenectomy as compared to 76 (54%) receiving a splenic preservation procedure. When evaluated by univariate analysis, although VAP rates were higher (26.3 %vs. 15.6%) in the splenic preservation group, it was not statistically significant (p=0.125). As expected, when analyzed by multivariate regression, increased ventilator days was associated with a higher incidence of VAP (OR: 1.095, 95%, CI: 1.037-1.157, p<0.001). Splenectomy alone was not associated with a greater incidence of VAP (OR: 0.473, 95%, CI 0.156-1.434, p=0.186).

Conclusions:

Splenectomy alone is not associated with an increased incidence of VAP among patients with splenic injuries. As expected, increased ventilator days were associated with a greater risk of VAP.