Identifying Age-Specific Risk Factors for Poor Outcomes After Trauma With Machine Learning.

INTRODUCTION: Risk stratification for poor outcomes is not currently age-specific. Risk stratification of older patients based on observational cohorts primarily composed of young patients may result in suboptimal clinical care and inaccurate quality benchmarking. We assessed two hypotheses. First, we hypothesized that risk factors for poor outcomes after trauma are age-dependent and, second, that the relative importance of various risk factors are also age-dependent. METHODS: A cohort study of severely injured adult trauma patients admitted to the intensive care unit 2014-2018 was performed using trauma registry data. Random forest algorithms predicting poor outcomes (death or complication) were built and validated using three cohorts: (1) patients of all ages, (2) younger patients, and (3) older patients. Older patients were defined as aged 55 y or more to maintain consistency with prior trauma literature. Complications assessed included acute renal failure, acute respiratory distress syndrome, cardiac arrest, unplanned intubation, unplanned intensive care unit admission, and unplanned return to the operating room, as defined by the trauma quality improvement program. Mean decrease in model accuracy (MDA), if each variable was removed and scaled to a Z-score, was calculated. MDA change ≥4 standard deviations between age cohorts was considered significant. RESULTS: Of 5489 patients, 25% were older. Poor outcomes occurred in 12% of younger and 33% of older patients. Head injury was the most important predictor of poor outcome in all cohorts. In the full cohort, age was the most important predictor of poor outcomes after head injury. Within age cohorts, the most important predictors of poor outcomes, after head injury, were surgery requirement in younger patients and arrival Glasgow Coma Scale in older patients. Compared to younger patients, head injury and arrival Glasgow Coma Scale had the greatest increase in importance for older patients, while systolic blood pressure had the greatest decrease in importance. CONCLUSIONS: Supervised machine learning identified differences in risk factors and their relative associations with poor outcomes based on age. Age-specific models may improve hospital benchmarking and identify quality improvement targets for older trauma patients.

Impact of Intra-Operative Shock and Resuscitation on Surgical Site Infections After Trauma Laparotomy.

Background: Patients undergoing trauma laparotomy experience high rates of surgical site infection (SSI). Although intra-operative shock is a likely contributor to SSI risk, little is known about the relation between shock, intra-operative restoration of physiologic normalcy, and SSI development. Patients and Methods: A retrospective review of trauma patients who underwent emergent definitive laparotomy was performed. Using shock index and base excess at the beginning and end of laparotomy, patients were classified as normal, persistent shock, resuscitated, or new shock. Univariable and multivariable analyses were performed to identify predictors of organ/space SSI, superficial/deep SSI, and any SSI. Results: Of 1,191 included patients, 600 (50%) were categorized as no shock, 248 (21%) as resuscitated, 109 (9%) as new shock, and 236 (20%) as persistent shock, with incidence of any SSI as 51 (9%), 28 (11%), 26 (24%), and 32 (14%), respectively. These rates were similar in organ/space and superficial/deep SSIs. On multivariable analysis, resuscitated, new shock, and persistent shock were associated with increased odds of organ/space SSI (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.3-3.5; p < 0.001) and any SSI (OR, 2.0; 95% CI, 1.4-3.2; p < 0.001), but no increased risk of superficial/deep SSI (OR, 1.4; 95% CI, 0.8-2.6; p = 0.331). Conclusions: Although the trajectory of physiologic status influenced SSI, the presence of shock at any time during trauma laparotomy, regardless of restoration of physiologic normalcy, was associated with increased odds of SSI. Further investigation is warranted to determine the relation between peri-operative shock and SSI in trauma patients.

Dysphagia is associated with worse clinical outcomes in geriatric trauma patients.

Introduction: Dysphagia is associated with increased morbidity, mortality, and resource utilization in hospitalized patients, but studies on outcomes in geriatric trauma patients with dysphagia are limited. We hypothesized that geriatric trauma patients with dysphagia would have worse clinical outcomes compared with those without dysphagia. Methods: Patients with and without dysphagia were compared in a single-center retrospective cohort study of trauma patients aged ≥65 years admitted in 2019. The primary outcome was mortality. Secondary outcomes included intensive care unit (ICU) length of stay (LOS), hospital LOS, discharge destination, and unplanned ICU admission. Multivariable regression analyses and Bayesian analyses adjusted for age, Injury Severity Score, mechanism of injury, and gender were performed to determine the association between dysphagia and clinical outcomes. Results: Of 1706 geriatric patients, 69 patients (4%) were diagnosed with dysphagia. Patients with dysphagia were older with a higher Injury Severity Score. Increased odds of mortality did not reach statistical significance (OR 1.6, 95% CI 0.6 to 3.4, p=0.30). Dysphagia was associated with increased odds of unplanned ICU admission (OR 4.6, 95% CI 2.0 to 9.6, p≤0.001) and non-home discharge (OR 5.2, 95% CI 2.4 to 13.9, p≤0.001), as well as increased ICU LOS (OR 4.9, 95% CI 3.1 to 8.1, p≤0.001), and hospital LOS (OR 2.1, 95% CI 1.7 to 2.6, p≤0.001). On Bayesian analysis, dysphagia was associated with an increased probability of longer hospital and ICU LOS, unplanned ICU admission, and non-home discharge. Conclusions: Clinically apparent dysphagia is associated with poor outcomes, but it remains unclear if dysphagia represents a modifiable risk factor or a marker of underlying frailty, leading to poor outcomes. This study highlights the importance of screening protocols for dysphagia in geriatric trauma patients to possibly mitigate adverse outcomes. Level of evidence: Level III.

The Geriatric Nutritional Risk Index as a predictor of complications in geriatric trauma patients.

BACKGROUND: Malnutrition is associated with increased morbidity and mortality after trauma. The Geriatric Nutritional Risk Index (GNRI) is a validated scoring system used to predict the risk of complications related to malnutrition in nontrauma patients. We hypothesized that GNRI is predictive of worse outcomes in geriatric trauma patients. METHODS: This was a single-center retrospective study of trauma patients 65 years or older admitted in 2019. Geriatric Nutritional Risk Index was calculated based on admission albumin level and ratio of actual body weight to ideal body weight. Groups were defined as major risk (GNRI <82), moderate risk (GNRI 82-91), low risk (GNRI 92-98), and no risk (GNRI >98). The primary outcome was mortality. Secondary outcomes included ventilator days, intensive care unit length of stay (LOS), hospital LOS, discharge home, sepsis, pneumonia, and acute respiratory distress syndrome. Bivariate and multivariable logistic regression analyses were performed to determine the association between GNRI risk category and outcomes. RESULTS: A total of 513 patients were identified for analysis. Median age was 78 years (71-86 years); 24 patients (4.7%) were identified as major risk, 66 (12.9%) as moderate risk, 72 (14%) as low risk, and 351 (68.4%) as no risk. Injury Severity Scores and Charlson Comorbidity Indexes were similar between all groups. Patients in the no risk group had decreased rates of death, and after adjusting for Injury Severity Score, age, and Charlson Comorbidity Index, the no risk group had decreased odds of death (odds ratio, 0.13; 95% confidence interval, 0.04-0.41) compared with the major risk group. The no risk group also had fewer infectious complications including sepsis and pneumonia, and shorter hospital LOS and were more likely to be discharged home. CONCLUSIONS: Major GNRI risk is associated with increased mortality and infectious complications in geriatric trauma patients. Further studies should target interventional strategies for those at highest risk based on GNRI. LEVEL OF EVIDENCE: Prognostic and Epidemiologic; Level III.

Shock-Induced Endothelial Dysfunction is Present in Patients With Occult Hypoperfusion After Trauma.

BACKGROUND: Shock-induced endothelial dysfunction, evidenced by elevated soluble thrombomodulin (sTM) and syndecan-1 (Syn-1), is associated with poor outcomes after trauma. The association of endothelial dysfunction and overt shock has been demonstrated; it is unknown if hypoperfusion in the setting of normal vital signs (occult hypoperfusion [OH]) is associated with endothelial dysfunction. We hypothesized that sTM and Syn-1 would be elevated in patients with OH when compared to patients with normal perfusion. METHODS: A single-center study of patients requiring highest-level trauma activation (2012-2016) was performed. Trauma bay arrival plasma Syn-1 and sTM were measured by enzyme-linked immunosorbent assay. Shock was defined as systolic blood pressure (SBP) <90 mm Hg or heart rate (HR) ≥120 bpm. OH was defined as SBP ≥ 90, HR < 120, and base excess (BE) ≤-3. Normal perfusion was assigned to all others. Univariate and multivariable analyses were performed. RESULTS: Of 520 patients, 35% presented with OH and 26% with shock. Demographics were similar between groups. Patients with normal perfusion had the lowest Syn-1 and sTM, while patients with OH and shock had elevated levels. OH was associated with increased sTM by 0.97 ng/mL (95% CI 0.39-1.57, p = 0.001) and Syn-1 by 14.3 ng/mL (95% CI -1.5 to 30.2, p = 0.08). Furthermore, shock was associated with increased sTM by 0.64 (95% CI 0.02-1.30, p = 0.04) and with increased Syn-1 by 23.6 ng/mL (95% CI 6.2-41.1, p = 0.008). CONCLUSIONS: Arrival OH was associated with elevated sTM and Syn-1, indicating endothelial dysfunction. Treatments aiming to stabilize the endothelium may be beneficial for injured patients with evidence of hypoperfusion, regardless of vital signs.

Age-related Opioid Exposure in Trauma: A Secondary Analysis of the Multimodal Analgesia Strategies for Trauma (MAST) Randomized Trial.

OBJECTIVE: Evaluate the effect of age on opioid consumption after traumatic injury. SUMMARY BACKGROUND DATA: Older trauma patients receive fewer opioids due to decreased metabolism and increased complications, but adequacy of pain control is unknown. We hypothesized that older trauma patients require fewer opioids to achieve adequate pain control. METHODS: A secondary analysis of the multimodal analgesia strategies for trauma Trial evaluating the effectiveness of 2 multimodal pain regimens in 1561 trauma patients aged 16 to 96 was performed. Older patients (≥55 years) were compared to younger patients. Median daily oral morphine milligram equivalents (MME) consumption, average numeric rating scale pain scores, complications, and death were assessed. Multivariable analyses were performed. RESULTS: Older patients (n = 562) had a median age of 68 years (interquartile range 61-78) compared to 33 (24-43) in younger patients. Older patients had lower injury severity scores (13 [9-20] vs 14 [9-22], P = 0.004), lower average pain scores (numeric rating scale 3 [1-4] vs 4 [2-5], P < 0.001), and consumed fewer MME/day (22 [10-45] vs 52 [28-78], P < 0.001). The multimodal analgesia strategies for trauma multi-modal pain regimen was effective at reducing opioid consumption at all ages. Additionally, on multivariable analysis including pain score adjustment, each decade age increase after 55 years was associated with a 23% reduction in MME/day consumed. CONCLUSIONS: Older trauma patients required fewer opioids than younger patients with similar characteristics and pain scores. Opioid dosing for post-traumatic pain should consider age. A 20 to 25% dose reduction per decade after age 55 may reduce opioid exposure without altering pain control.

Preterm Preeclampsia with Severe Features: Composite Maternal and Neonatal Morbidities Associated with Fetal Growth Restriction.

OBJECTIVE: The objective of this study was to compare adverse pregnancy outcomes between fetuses with estimated fetal weight (EFW) < 10 to > 10% in women with preterm preeclampsia (PE) with severe features. MATERIALS AND METHODS: All women with preterm PE with severe features and nonanomalous singletons with EFW were identified at a tertiary center. Women with oligohydramnios or absent/reversed umbilical Doppler velocimetry were excluded. Using multivariable analysis, we compared the composite maternal and neonatal morbidities (CMM and CNM) between those with appropriate for gestational age (AGA) fetal growth, defined as EFW at 10 to 90th versus those with fetal growth restriction (FGR), defined as EFW < 10th percentile for gestational age (GA). RESULTS: In this study, 165 patients were included; 112 had EFW at 10th to 90th percentile, and 53 had FGR. Of the 53 with FGR, 33 (62%) had EFW at 5 to 9% for GA and 20 (38%) had EFW < fifth percentile for GA. The CMM was significantly higher among women with FGR versus AGA (29 vs. 7%; p < 0.001). The CNM was significantly higher with FGR versus AGA (20 vs. 6%; p = 0.01). CONCLUSION: Women with preterm PE with severe features and FGR, when compared with those with AGA, have significantly higher risk of CMM and CNM.