Obesity Protects Against Operation in Pediatric Penetrating Trauma to the Torso

Relationship of Obesity and Severe Penetrating Thoracic and Abdominal Injuries in Adolescent Patients

BACKGROUND

Over 20% of United States adolescents are obese. A thicker layer of subcutaneous adiposity might provide a protective "armor" layer against penetrating wounds. We hypothesized that adolescents with obesity presenting after isolated thoracic and abdominal penetrating trauma have lower rates of severe injury and mortality than adolescents without obesity.

METHODS

The 2017-2019 Trauma Quality Improvement Program database was queried for patients between 12 and 17 years old presenting with knife or gunshot wounds. Patients with body mass index (BMI) ≥30 (obese) were compared to patients with BMI <30. Sub-analyses were performed for adolescents with isolated abdominal trauma and isolated thoracic trauma. Severe injury was defined as an abbreviated injury scale grade >3. Bivariate analyses were performed.

RESULTS

12,181 patients were identified; 1603 (13.2%) had obesity. In isolated abdominal gunshot or knife wounds, rates of severe intra-abdominal injuries and mortality were similar (all P > .05) between groups. In isolated thoracic gunshot wounds, adolescents with obesity had a lower rate of severe thoracic injury (5.1% vs 13.4%, P = .005) but statistically similar mortality (2.2% vs 6.3%, P = .053) compared to adolescents without obesity. In isolated thoracic knife wounds, rates of severe thoracic injuries and mortality were similar (all P > .05) between groups.

DISCUSSION

Adolescent trauma patients with and without obesity presenting after isolated abdominal or thoracic knife wounds had similar rates of severe injury, operative intervention, and mortality. However, adolescents with obesity presenting after an isolated thoracic gunshot wound had a lower rate of severe injury. This may impact the future work-up and management of adolescents sustaining isolated thoracic gunshot wounds.

Subcutaneous and visceral fat are associated with worse outcomes in gunshot injuries but not stab injuries to the torso

Purpose

The effect of obesity in penetrating trauma outcomes is poorly understood. The purpose of this study was to determine if there is a protective effect of subcutaneous or visceral fat from stab and gunshot wounds.

Methods

443 patients admitted after penetrating traumatic injury of the torso were retrospectively identified from our institution's trauma registry. CT scans performed at presentation were used to determine cross-sectional area of visceral and subcutaneous fat at the level of the umbilicus via manual segmentation. Obesity-associated parameters including body mass index, visceral and subcutaneous fat were compared with injury severity score, length of hospital/intesive care unit (ICU) stay, and number of operating room (OR) visits. Parameters were compared between patients who sustained stab wounds versus gunshot injuries.

Results

Comparing all patients with gunshot injuries with those with stab injuries, gunshots resulted in increased hospital and ICU length of stay, and injury severity score (ISS). For patients with gunshot wounds, all obesity-related parameters correlated with increased length of stay and total ICU stay; subcutaneous fat and visceral fat were correlated with increased OR visits, but there was no significant correlation between obesity-related parameters and ISS. In contrast, with stab wounds there were no statistically significant associations between obesity parameters and any of the outcome measures.

Conclusion

For penetrating trauma in the torso, obesity is correlated with worse outcomes with gunshot injuries but not in stab injuries.

Level of evidence

Level III, prognostic and epidemiological.

'The Armor Phenomenon' in Obese Patients with Penetrating Thoracoabdominal Injuries: A Systematic Review and Meta-Analysis

BACKGROUND

Obesity represents a growing global health threat, which generally portends increased morbidity and mortality in the context of traumatic injuries. We hypothesized that there may exist a protective effect related to increased weight and truncal girth provided for obese patients in penetrating torso injuries, although this may not exert a significant positive impact overall upon clinical outcomes.

METHODS

A comprehensive review of the literature was conducted across five databases up to March 2021 (Medline, Pubmed, Embase, Web of Science and the Cochrane library) to examine the effect of obesity on penetrating thoracoabdominal injuries. The primary outcome was to determine the rate of non-significant injury and injury patterns. Secondary outcomes examined were lengths of stay, complications, and mortality. Comparisons were drawn by meta-analysis. The study protocol was registered with PROSPERO under CRD42020216277.

RESULTS

2,952 publications were assessed with twelve meeting the inclusion criteria for review. Nine studies were included for quantitative analysis including 5,013 patients sustaining penetrating thoracoabdominal injuries, of which 29.6% were obese. Obese patients that sustained stab injuries underwent more non-therapeutic operations. Obese patients that sustained gunshot injuries had longer intensive care and total hospital length of stay. Obese patients suffered more respiratory complications and were at an increased risk of death during their admission.

CONCLUSION

The 'armor phenomenon' does not truly protect obese patients, a population that experiences increased morbidity and mortality following penetrating thoracoabdominal injuries.

LEVEL OF EVIDENCE

Systematic Review and Meta-Analysis, prognostic Level III.