Search Results (94)

Background: Shock index (SI) is calculated by dividing heart rate (HR) by systolic blood pressure (sBP) and is a useful tool for predicting the prognosis of trauma patients. This study aimed to determine whether SI is useful in predicting mortality in patients undergoing emergency surgery for trauma. Methods: We analyzed 1657 patients who underwent emergency surgery for trauma. Patients were divided into SI < 1 and SI ≥ 1 groups and the Glasgow Coma Scale (GCS), Injury Severity Score (ISS), revised trauma score (RTS), Korean Triage and Acuity Scale (KTAS), transfusion amount, and mortality were compared. Binary logistic regression analysis was performed to identify factors associated with mortality. Results: There were significant differences in GCS, ISS, RTS, and KTAS in the SI ≥ 1 group compared to the SI < 1 group (all p-values < 0.001). In the SI < 1 cohort, the mortality rate was 11% (144/1283), and in the SI ≥ 1 group the mortality rate was 33% (125/374) (p < 0.001). Age, GCS, ISS, SI ≥ 1, and KTAS were determined to be predictors of mortality by logistic regression analysis. In particular, SI ≥ 1 group members exhibited a high association with elevated mortality (OR, 2.498; 95% CI, 1.708–3.652; p < 0.01). Conclusions: Although SI alone has limitations in predicting the patient’s prognosis, patients with SI ≥ 1 upon arrival at the emergency room are associated with mortality of patients undergoing emergency surgery for trauma, along with already known trauma assessment systems such as GCS, ISS, and KTAS. Full article

Background/Objectives: Early neuroprognostication after cardiac arrest is essential for guiding treatment strategies and providing accurate prognostic information to families. While several early risk scores have been proposed, few have incorporated a wide range of variables in large cohorts. This study aimed to develop and validate a novel prognostic model, the KORHN risk score, and to compare its performance with established tools including MIRACLE, TTM, CAHP, C-GRApH, and OHCA scores; Methods: We conducted a prospective multicenter observational study using data from the KORean Hypothermia Network registry. Risk variables identified in previous studies, along with extensive data from 1371 patients in the KORHN registry, were analyzed. The primary endpoint was poor neurological outcome at 6 months; Results: Key predictors included low-flow time, diastolic shock index, cardiac etiology, bilateral absence of pupil reflex, shockable initial rhythm, Glasgow Coma Scale motor response, epinephrine use, and age. Compared with established risk scores, the KORHN score demonstrated superior performance (AUC 0.925 vs. 0.827–0.902 with all variables, and AUC 0.914 vs. 0.85–0.903 with the top five variables with identical cut-off). External validation in a non-KORHN cohort (AUC 0.890) confirmed its robustness; Conclusions: The KORHN score provides a simple, accurate tool for early neuroprognostication, supporting clinical decision-making and family communication. Full article

Norepinephrine (NE) and dopamine (DA) are vasopressors used to treat vasodilatory shock for decades, and norepinephrine is considered the preferred first-line vasopressor in human patients. However, there is a dearth of evidence to support specific treatment recommendations for the management of hypotensive, non-anesthetized, fluid-replete dogs. The objective of this study was to compare the effects of NE and DA on systolic blood pressure (SBP), heart rate, and shock index (SI) when used as first-line vasopressors for the treatment of vasodilatory shock in dogs. Twenty-four client-owned canine patients of similar age, sex, and weight with hypotension necessitating vasopressor therapy were randomized to receive NE or DA; attending clinicians were blinded. Twenty-two dogs were included in the final analysis (10 in the NE group and 12 in the DA group). Seventy-seven percent of all dogs achieved normotension. In both groups, SBP increased significantly compared to baseline (p = 0.0004 in the NE group and p = 0.006 in the DA group). The SI also decreased in both groups compared to baseline values (p = 0.01 in the NE group and p = 0.01 in the DA group). The heart rate in the NE group was higher than in the DA group at timepoints 6–10 (p = 0.023). Both NE and DA cause an increase in blood pressure and a decrease in SI in dogs with vasodilatory hypotension. Further investigation is warranted to determine if there are differences between NE and DA or the requirement for a second vasopressor, occurrence of arrhythmias, length of stay, and survival. Full article

Background: Patients with end-stage heart failure-related cardiogenic shock (HF-CS) are conclusively associated with a poor health-related quality of life (HRQL). Axillary mechanical circulatory support (aMCS), such as the Impella 5.5, is increasingly used in this population and may improve HRQL during hospitalization by providing enhanced left ventricular unloading. We aimed to assess changes in HRQL between admission and two weeks after Impella 5.5 placement in patients with HF-CS, using the Kansas City Cardiomyopathy Questionnaire (KCCQ). Methods: We conducted a prospective longitudinal analysis on patients with the Impella 5.5 between May 2023 and July 2023. Participants completed the condensed KCCQ-12 at admission and again two weeks post-implantation. Changes in the scores were evaluated using the Wilcoxon signed-rank test. Results: Fifteen patients were enrolled. The median age was 59 years (50–63), and the median ejection fraction at implantation was 20% (15–30). On admission, most patients reported an overall HRQL of poor-to-fair (46.7%) according to the summary KCCQ-12 score. The median overall summary score increased significantly after Impella 5.5 support (50.52 vs. 28.13, p = 0.005). Symptom frequency (70.83 vs. 43.75, p = 0.009) and quality-of-life (50.00 vs. 12.50, p = 0.023) domains improved significantly, while physical limitation showed a positive trend and social limitation remained unchanged. These HRQL improvements occurred alongside a significant shift toward lower SCAI shock stages, marked increases in cardiac output and cardiac index, and no escalation in vasoactive-inotropic requirements. Conclusions: Impella 5.5 support in HF-CS patients was associated with early and clinically meaningful improvements in HRQL, particularly in symptom frequency and quality of life, during the critical pre-transplant or recovery period. These findings suggest that the Impella 5.5 may provide both physiological and patient-perceived benefits in this high-risk population. Full article

Background/Objectives: This study evaluates the outcomes of extracorporeal membrane oxygenation (ECMO), in venoarterial configuration, and short-term ventricular assist devices (VADs) used as a bridge to heart transplantation (HT). The primary objective was to identify predictors of in-hospital mortality among patients on the urgent HT waiting list receiving short-term mechanical circulatory support, including direct ECMO-to-HT, direct short-term VAD-to-HT, and ECMO as a bridge to short-term VAD followed by HT (ECMO bridge-to-bridge). Secondary objectives included identifying predictors of in-hospital mortality in transplanted patients and assessing their long-term survival. Methods: A single-center, retrospective, observational, and analytical study conducted at a tertiary care hospital, including patients supported with ECMO and short-term VAD support as a bridge to HT between 2007 and 2024. Results: A total of 183 patients were included: 110 in the ECMO-to-HT group, 51 in the VAD-to-HT group, and 22 in the ECMO bridge-to-bridge group. Among them, 147 underwent HT (80.3%). Overall in-hospital mortality was 37.2% (115 of 183 patients survived), while in-hospital mortality among transplanted patients was 21.8% (115 of 147 survived). Independent predictors of in-hospital mortality included infection, ECMO bridge-to-bridge strategy, higher body mass index (BMI), older age, and neurological complications. In the transplanted subgroup, predictors of both in-hospital and long-term mortality were ECMO support and older recipient age. Notably, a donor BMI exceeding that of the recipient by more than 10% was associated with improved survival. Conclusions: The complexity of patients requiring mechanical circulatory support and the physiological effects of different devices necessitate early, individualized management based on the etiology of cardiogenic shock and urgency status. Full article

Introduction: The combination of ceftazidime−avibactam (CAZ-AVI) with aztreonam (ATM) may be an option for the treatment of infections due to metallo-β-lactamases (MBLs) producing bacteria, as recommended by current guidelines. MBLs protect the pathogen from any available β-lactam/β-lactamase inhibitor (BL/BLI). Moreover, in vitro and clinical data suggest that double carbapenem therapy (DCT) may be an option for such infections. Materials and Methods: This retrospective study was conducted in two mixed intensive care units (ICUs) at the University Hospital of Larissa, Thessaly, Greece, and the General Hospital of Larissa, Thessaly, Greece, during a three-year period (2022−2024). Mechanically ventilated patients with bloodstream infection (BSI) caused by K. pneumoniae resistant to all BL/BLI combinations were studied. Patients were divided into three groups: in the first, patients were treated with CAZ-AVI + ATM; in the second, with DCT; and in the third, with antibiotics other than BL/BLIs that presented in vitro susceptibility. The primary outcome of the study was the change in Sequential Organ Failure Assessment (SOFA) score between the onset of infection and the fourth day of antibiotic treatment. Secondary outcomes were SOFA score evolution during the treatment period, total duration of mechanical ventilation (MV), ICU length of stay (LOS), and ICU mortality. Results: A total of 95 patients were recruited. Among them, 23 patients received CAZ-AVI + AZT, 22 received DCT, and 50 patients received another antibiotic regimen which was in vitro active against the pathogen. The baseline characteristics were similar. The mean (SE) overall age was 63.2 (1.3) years. Mean (SE) Acute Physiology and Chronic Health Evaluation II (APACHE II) and SOFA scores were 16.3 (0.6) and 7.6 (0.3), respectively. The Charlson Index was similar between groups. The control group presented a statistically lower SOFA score on day 4 compared to the other two groups [mean (SE) 8.9 (1) vs. 7.4 (0.9) vs. 6.4 (0.5) for CAZ-AVI + ATM, DCT and control group, respectively (p = 0.045)]. The duration of mechanical ventilation, ICU LOS, and mortality were similar between the groups (p > 0.05). Comparison between survivors and non-survivors revealed that survivors had a lower SOFA score on the day of BSI, higher PaO₂/FiO₂ ratio, higher platelet counts, and lower lactate levels (p < 0.05). Septic shock was more frequent among non-survivors (60.3%) in comparison to survivors (27%) (p = 0.0015). Independent factors for mortality were PaO₂/FiO₂ ratio and lactate levels (p < 0.05). None of the antibiotic regimens received by the patients was independently associated with survival. Conclusions: Treatment with CAZ-AVI + ATM or DCT may offer similar clinical outcomes for patients suffering from BSI caused by K. pneumoniae strains resistant to all available BL/BLIs. However, larger studies are required to confirm the findings. Full article

Background: Acute kidney injury (AKI) frequently occurs following major liver resection, adversely affecting both short- and long-term outcomes. This study aimed to determine the incidence of AKI post-hepatectomy and identify relevant pre- and intraoperative risk factors. Our secondary objectives were to develop a predictive score for postoperative AKI and assess the associations between AKI, chronic kidney disease (CKD), and 1-year mortality. Methods: This was a retrospective study in a cancer referral center in Marseille, France, from 2018 to 2022. Results: Among 169 patients, 55 (32.5%) experienced AKI. Multivariate analysis revealed several independent risk factors for postoperative AKI, including age, body mass index, the use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, time to liver resection, intraoperative shock, and bile duct reconstruction. Neoadjuvant chemotherapy was protective. The AKIMEBO score was developed, with a threshold of ≥15.6, demonstrating a sensitivity of 89.5%, specificity of 76.4%, positive predictive value of 61.8%, and negative predictive value of 94.4%. AKI was associated with increased postoperative morbidity and one-year mortality following major hepatectomy. Conclusion: AKI is a common complication post-hepatectomy. Factors such as time to liver resection and intraoperative shock management present potential clinical intervention points. The AKIMEBO score can provide a valuable tool for postoperative risk stratification. Full article

Background: Renal trauma accounts for approximately 3–5% of all trauma cases, predominantly affecting young males. The most common etiology is blunt trauma, particularly due to road traffic accidents, and it frequently occurs as part of polytrauma involving multiple organ systems. Management strategies are primarily dictated by hemodynamic stability, overall clinical condition, comorbidities, and injury severity graded according to the AAST classification. This study aimed to evaluate the effectiveness of non-operative management (NOM) in high-grade renal trauma (AAST grades III–V), beyond its established role in low-grade injuries (grades I–II). Secondary endpoints included the identification of independent prognostic factors for NOM failure and in-hospital mortality. Methods: We conducted a retrospective observational study including patients diagnosed with blunt renal trauma who presented to the Emergency Department of Policlinico Umberto I in Rome between 1 January 2013 and 30 April 2024. Collected data comprised demographics, trauma mechanism, vital signs, hemodynamic status (shock index), laboratory tests, blood gas analysis, hematuria, number of transfused RBC units in the first 24 h, AAST renal injury grade, ISS, associated injuries, treatment approach, hospital length of stay, and mortality. Statistical analyses, including multivariable logistic regression, were performed using SPSS v28.0. Results: A total of 244 patients were included. Low-grade injuries (AAST I–II) accounted for 43% (n = 105), while high-grade injuries (AAST III–V) represented 57% (n = 139). All patients with low-grade injuries were managed non-operatively. Among high-grade injuries, 124 patients (89%) were treated with NOM, including observation, angiography ± angioembolization, stenting, or nephrostomy. Only 15 patients (11%) required nephrectomy, primarily due to persistent hemodynamic instability. The overall mortality rate was 13.5% (33 patients) and was more closely associated with the overall injury burden than with renal injury severity. Multivariable analysis identified shock index and active bleeding on CT as independent predictors of NOM failure, whereas ISS and age were significant predictors of in-hospital mortality. Notably, AAST grade did not independently predict either outcome. Conclusions: In line with the current international literature, our study confirms that NOM is the treatment of choice not only for low-grade renal injuries but also for carefully selected hemodynamically stable patients with high-grade trauma. Our findings highlight the critical role of physiological parameters and overall ISS in guiding management decisions and underscore the need for individualized assessment to minimize unnecessary nephrectomies and optimize patient outcomes. Full article

Introduction: Leptospirosis is an under-recognized zoonosis that affects both tropical and temperate regions. While it is often associated with exposure to contaminated water or infected animals, its presentation and epidemiology in Mediterranean countries remain incompletely understood. This retrospective cohort study investigates the clinical and epidemiological profile of leptospirosis in Crete, Greece, a region where data are scarce. Methods: All adult patients with laboratory-confirmed leptospirosis admitted to three major public hospitals in Crete, Greece, between January 2019 and December 2023 were included in the analysis. Diagnosis was made through serologic testing along with compatible clinical symptoms. Results: A total of 17 patients were included. Their median age was 48 years, with a predominance of males (70.6%). Notably, more than half of the patients had no documented exposure to classic risk factors such as rodents or standing water. Clinical presentations were varied but commonly included fever, fatigue, acute kidney injury, and jaundice. Of the patients who underwent imaging, most showed hepatomegaly. The median delay from symptom onset to diagnosis was 11 days, underscoring the diagnostic challenge in non-endemic areas. Ceftriaxone was the most frequently administered antibiotic (76.5%), often in combination with tetracyclines or quinolones. Despite treatment, three patients (17.6%) died, all presenting with severe manifestations such as ARDS, liver failure, or shock. A concerning increase in cases was noted in 2023. Conclusions: Leptospirosis can present with severe and potentially fatal outcomes even in previously healthy individuals and in regions not traditionally considered endemic. The relatively high mortality and disease frequency noted emphasize the importance of maintaining a high index of suspicion. Timely diagnosis and appropriate antimicrobial therapy are essential to improving patient outcomes. Additionally, the need for enhanced public health awareness, diagnostic capacity, and possibly environmental surveillance to control this neglected but impactful disease better, should be emphasized. Full article

Background: Patients with ST-elevation myocardial infarction (STEMI) and multivessel coronary artery disease (MVD) who undergo complete revascularization (CR) have a more favorable prognosis than those who receive incomplete revascularization (IR), as evidenced by recent randomized controlled trials. Despite the absence of a survival benefit associated with CR in these trials, positive outcomes were ascribed to combined endpoints, such as repeat revascularization, myocardial infarction, or ischemia-driven rehospitalization. In light of the significant burden that rehospitalization from STEMI imposes on healthcare systems, we examined the long-term effects of CR on ischemia-driven rehospitalization and cardiovascular (CV) mortality in STEMI patients with MVD. Methods: In our retrospective study, we included patients with STEMI and MVD who underwent successful primary percutaneous coronary intervention (PCI) at the University Medical Centre Ljubljana between 1 January 2009, and 11 April 2011. The combined endpoint was ischemia-driven rehospitalization and CV mortality, with a minimum follow-up period of six years. Results: We included 235 participants who underwent CR (N = 70) or IR (N = 165) at index hospitalization, with a median follow-up time of 7 years (interquartile range 6.0–8.2). The primary endpoint was significantly higher in the IR group than in the CR group (47.3% vs. 32.9%, log-rank p = 0.025), driven by CV mortality (23.6% vs. 12.9%, log-rank p = 0.047), as there was no difference in ischemia-driven rehospitalization rate (log-rank p = 0.206). Ischemia-driven rehospitalization did not influence CV mortality in the CR group (p = 0.49), while it significantly impacted CV mortality in the IR group (p = 0.03). After adjusting for confounders, there were no differences in CV mortality between CR and IR groups (p = 0.622). Predictors of the combined endpoint included age (p = 0.014), diabetes (p = 0.006), chronic kidney disease (CKD) (p = 0.001), cardiogenic shock at presentation (p = 0.003), chronic total occlusion (CTO) (p = 0.046), and ischemia-driven rehospitalization (p = 0.0001). Significant risk factors for the combined endpoint were cardiogenic shock at presentation (p < 0.001), stage 4 kidney failure (p = 0.001), age over 70 years (p = 0.004), female gender (p = 0.008), and residual SYNTAX I score > 5.5 (p = 0.017). Conclusions: Patients with STEMI and MVD who underwent CR had a lower combined endpoint of ischemia-driven rehospitalizations and CV mortality than IR patients, but after adjustments for confounders, the true determinants of the combined endpoint and risk factors for the combined endpoint were independent of the revascularization method. Full article

Background/Objectives: Atrial fibrillation (AF) is a prevalent arrhythmia that significantly complicates the management of heart failure (HF) patients, particularly those who have implantable cardioverter–defibrillators (ICDs). The interplay between AF and inappropriate ICD therapy poses a critical challenge in optimizing patient outcomes, as inappropriate shocks can lead to increased morbidity, psychological distress, and a reduced quality of life. We aimed to explore the various clinical and demographic predictors of AF in HF patients with indications for ICD implantation. Methods: This study included 122 patients who were indicated for ICD implantation and had undergone transthoracic echocardiography (TE). We evaluated the relationships between clinical and demographic factors and the occurrence of AF, which was recorded either before ICD implantation or during the follow-up period afterward. From our findings, we established predictors and a risk model for AF. Results: Out of 122 HF patients with ICDs, 52 (42.6%) experienced an episode of AF either prior to ICD implantation or during a follow-up period of 20.5 [6.0; 53.0] months, as recorded by the ICDs’ endogram. Patients with AF were older compared to those without AF (p < 0.001). Additionally, they exhibited a higher left ventricular early diastolic filling rate (LVE) (p = 0.006) and a greater left atrial index (LAI) (p = 0.002). These three factors—age, LVE and LAI—were found to be independently associated with AF in both univariable and multivariable logistic regression analyses. The final model, including age, LVE, and LAI, showed a good discrimination capability with an AUC of 0.775. At a cutoff value of >0.47, the model achieved a sensitivity of 67.3% and a specificity of 77.2% in identifying HF patients with ICDs at risk for AF. Conclusions: This study found that 42.6% of HF patients with ICDs experienced AF, with older age, higher LVE, and greater LAI identified as significant predictors. Full article

Background and Objectives: Although transesophageal or intracardiac echocardiography and radiofrequency needles are employed to guide transseptal puncture, their routine utilization is associated with substantial expense. No reports have analyzed the use of the foramen ovale position to effectively guide transseptal punctures on chest X-rays or computed tomography scout views, which are more cost-effective approaches to safely and effectively guide the procedure. We aimed to find the foramen ovale position on chest computed tomography scout views to effectively guide percutaneous transseptal punctures. Materials and Methods: The study population included 31 patients treated with extracorporeal membrane oxygenation (ECMO) for cardiogenic shock, 32 patients diagnosed with atrial fibrillation (AF) who underwent MDCT, and 197 patients who underwent MDCT for non-cardiac conditions. Vertebral body units, defined as the distance between two adjacent vertebral bodies (the sixth and seventh thoracic spines) inclusive of the intervertebral disk space, were used to express the distance from the carina to the foramen ovale on computed tomography scout views. Results: The mean vertebral body units, distance from the carina to the foramen ovale (carina–foramen ovale), and distance from the carina to the foramen ovale on chest computed tomography scout views (carina–foramen ovale vertebral body units⁻¹) were 2.3 ± 0.2 cm, 6.9 ± 0.9 cm, and 3.0 ± 0.3, respectively. Multivariate analysis showed significant correlations between the carina–foramen ovale vertebral body units⁻¹ and sex (β = 0.080; p = 0.028), body mass index (β = −0.020; p < 0.001), age (β = 0; p = 0.013), and the application of extracorporeal membrane oxygenation or the presence of atrial fibrillation (β = 0.130; p = 0.004). Conclusions: Although a three-dimensional approach was not employed, the foramen ovale position may serve as a radiologic guide in various clinical settings where transseptal punctures are required. This technique may be an effective aid in transseptal puncture procedures. Full article

Background: We aimed to evaluate the clinical significance of abnormal rotational thromboelastometry (ROTEM) findings in trauma patients and investigate the relationships between FIBTEM-maximum clot firmness (MCF), fibrinogen concentration and patient outcomes. Methods: A retrospective cohort analysis was conducted on adult trauma patients who underwent on-admission ROTEM testing between January 2020 and January 2021. Univariate analyses compared data based on injury severity, ROTEM findings (normal vs. abnormal), and initial fibrinogen concentration (normal vs. hypofibrinogenemia). ROC curve analysis was performed to determine the diagnostic performance of FIBTEM A10/MCF for its association with hypofibrinogenemia. Results: A total of 1488 patients were included in this study; the mean age was 36.4 ± 14.2 years and 92% were male. In total, 376 (25.3%) patients had ROTEM abnormalities. Severe injuries (ISS ≥ 16) were associated with a higher shock index, positive troponin T levels, standard coagulation abnormalities, hypofibrinogenemia, and abnormal ROTEM parameters (p < 0.05). These patients also had higher rates of massive transfusions and in-hospital mortality (p = 0.001). Coagulation alterations were significantly associated with higher injury severity score (ISS), shock index, head abbreviated injury score (AIS), hypofibrinogenemia, transfusion need, and mortality (p < 0.05). Hypofibrinogenemic patients were younger, sustained severe injuries, had higher shock indices and coagulation marker levels, required more intensive treatments, had longer hospital stays, and had higher mortality (p < 0.05). A significant positive correlation was found between plasma fibrinogen concentration and FIBTEM-MCF (r = 0.294; p = 0.001). Conclusions: Approximately one-fourth of the patients had early traumatic coagulopathy, as assessed by ROTEM. The FIBTEM A10/MCF may serves as a surrogate marker for plasma fibrinogen concentration. While prior studies have established the link between ROTEM and injury severity, our findings reinforce its relevance across varying trauma severity levels. However, prospective studies are warranted to validate its role within diverse trauma systems and evolving resuscitation protocols. Full article

Background/Objectives: Despite the growing burden caused by pediatric trauma, the accuracy of prehospital triage remains suboptimal due to the lack of reliable pediatric-specific tools. In this study, we aimed to evaluate the predictive validity of the reverse shock index multiplied by the Glasgow Coma Scale (rSIG) for in-hospital mortality in pediatric trauma patients and to determine appropriate age-specific rSIG cutoff values for triage use. Methods: We conducted a multicenter retrospective observational study using data from the Korean Emergency Department-Based Injury In-Depth Surveillance registry; these data covered trauma patients aged ≤18 years, spanning the period from 2011 to 2022. The rSIG was calculated using the initial vital signs and Glasgow Coma Scale scores upon arrival at the emergency department. Age groups with shared rSIG cutoffs were identified using the area under the receiver operating characteristic curve (AUC) and Akaike information criterion. Cutoff values were derived using the Youden index or further optimized to align with triage goals (<5% under-triage, <35% over-triage). Results: Among 333,995 pediatric trauma patients, the in-hospital mortality rate was 0.07%. The rSIG cutoff values derived using the Youden index showed strong predictive performance, with an AUC of 0.920 (95% CI: 0.897–0.943). The cutoff values adjusted to meet triage goals—13.3 for those aged 0–9 years, 18.4 for 10–14 years, and 20.9 for 15–18 years—achieved the best balance, with 30.94% over-triage and 9.17% under-triage. Conclusions: The rSIG is a reliable predictor of in-hospital mortality in pediatric trauma cases. We recommend using cutoff values that are optimized to meet triage goals. Further research is warranted to develop standardized methods to derive triage-appropriate cutoff values. Full article

Background: In trauma, the shock index (SI) is commonly used to assess the presence of significant blood loss. Prior studies have shown that the SI has a fair predictive ability for clinical outcomes such as massive transfusion (MT) or mortality in adult trauma patients. We hypothesized that the relatively lower predictive power of the SI in older adult patients compared to that of younger adult patients results in the overall fair predictive ability of the SI for clinical outcomes in adult trauma patients. Methods: This retrospective observational study analyzed adult trauma patients who presented to a single regional trauma center between 2019 and 2023, categorizing them into younger (18–64 years) and older (≥65 years) cohorts. The association between SI and MT was evaluated using simple logistic regression, while the modifying effect of age on this association was evaluated through an interaction model. The predictive performance was compared between the groups using the area under the receiver operating characteristic curve (AUC). Age-stratified AUC trends were visualized using cubic spline analysis. Results: A total of 2404 trauma patients met the inclusion criteria, including 1531 younger adults and 873 older adults. The SI was identified as an independent predictor of MT, with a stronger association in younger adults. The AUC for predicting MT was significantly higher in younger adults compared to older adults (0.801 vs. 0.666; p < 0.001), with optimal SI cut-off values of 1.18 and 0.88, respectively. Age-stratified analysis showed the highest AUC in the 41–50 age group (AUC 0.880; 95% CI, 0.836–0.916) and the lowest in the 71–80 age group (AUC 0.624; 95% CI, 0.573–0.674). Conclusions: The predictive performance of the SI for MT was influenced by age, demonstrating a lower predictive ability in older adult patients compared to younger adults. Full article