Introduction
Trauma centers across the United States form a vital network of comprehensive care designed to meet the needs of patients with traumatic injuries.1 These centers achieve designations ranging from Level I to Level IV, with Level I indicating the highest standard of trauma care. Designation is based on a facility’s ability to provide specific resources and services tailored to the needs of its region and population. In 1987, the American College of Surgeons (ACS) established a verification process to evaluate trauma centers based on their compliance with criteria corresponding to each level of designation.2 Level I trauma centers are distinguished by their ability to deliver the full continuum of care, from initial resuscitation through rehabilitation, and often serve as regional referral centers.1
Geospatial analyses have consistently shown that trauma centers are concentrated in densely populated areas.3 As a result, patients in sparsely populated states such as Alaska, Montana, Wyoming, and the Dakotas frequently face substantial geographic barriers to accessing trauma care. In these rural regions, definitive trauma care may be located hundreds of miles away, and delays in access are linked to worse clinical outcomes.4 These challenges are further compounded by environmental and infrastructural factors, such as mountainous terrain, severe weather, and hazardous road conditions, which can impede or prevent timely ground or air transport.3,5
Expanding trauma systems in ways that are responsive to local resources and population needs is also crucial, particularly in rural states.6 In Montana, for example, elderly residents over age 65 and American Indian/Native American populations have reduced access to not only the highest level, but any level of trauma care.7 Although much of the US population resides within one hour of trauma care, approximately 30 million individuals remain outside this critical access window.8 Furthermore, patients injured in areas with higher median age, lower per capita income, or greater distance from Level I or II centers have the highest odds of death.9
Comparative studies have demonstrated that Level I trauma centers offer improved long-term outcomes, including lower morbidity and mortality, compared to Level II centers.10–12 These findings highlight the critical importance of ensuring access to the highest levels of trauma care, particularly for patients with complex or severe injuries. Yet, according to Shekhar and Lewis,13 the three least populated states, Alaska, Montana, and Wyoming, lacked an in-state Level I trauma center. As a result, patients were often transferred out of state to distant Level I trauma centers, typically accessible only via fixed-wing aircraft, with transport times that can exceed two hours. These extended delays can worsen clinical outcomes and place additional emotional and logistical burdens on patients and their families.14,15
While outcomes associated with Level I trauma centers have been extensively studied, little literature describes the operational and organizational processes required for rural trauma centers to achieve Level I verification. Most published reports focus on urban academic centers, leaving limited evidence regarding implementation strategies in geographically isolated regions with workforce shortages and lower patient volumes.
During the study period, the trauma population served by this institution was predominantly composed of patients with blunt injuries, reflecting the injury patterns typical of many rural trauma systems.16 Because injury mechanisms influence resource utilization, critical care requirements, and trauma system planning, understanding how centers serving largely blunt-trauma populations achieve Level I readiness may provide valuable insights for other geographically isolated regions.
Against this backdrop, a rural Level II trauma center in Montana undertook a phased initiative to pursue American College of Surgeons (ACS) Level I trauma verification. Key milestones included surpassing the Injury Severity Score (ISS) volume threshold, establishing a dedicated surgically directed Intensive Care Unit (SICU), launching a surgical residency track, and developing trauma-focused research infrastructure. These efforts occurred alongside evolving patient demographics, including increasing volumes of geriatric trauma, rising intensive care unit (ICU) acuity, and changing transfer patterns.
This study evaluates the organizational, workforce, infrastructure, and clinical system changes associated with a rural trauma center’s transition toward ACS Level I verification. By providing a longitudinal perspective on trauma system development in a resource-constrained rural setting, the findings may offer practical implementation strategies for other rural trauma centers seeking to enhance trauma care delivery and achieve higher levels of trauma system maturity.
Materials and Methods
Study Design and Oversight
This was a single-center, retrospective study spanning twelve years prior to American College of Surgeons (ACS) Level I trauma verification. Institutional approval was obtained from the Billings Clinic Institutional Review Board (Privacy and Exemption Committee; Project #24.003). Which determined the study to be exempt under 45 CFR 46.102(l) because only deidentified data was used, the requirement for informed consent was waived. The study was conducted in accordance with the ethical principles outlined in the Declaration of Helsinki.
Setting and Population
This study was conducted at a rural trauma center located in the Upper Mountain West region, which expanded from 280 beds in 2011 to 305 beds in 2022, and served as a regional referral facility for four states throughout the study period. At the time of the study, the facility was an ACS-verified Level II trauma center. Following implementation of these initiatives and successful external review, the institution achieved ACS Level I trauma center verification in 2023.
Deidentified patient data was obtained from the institution’s trauma registry. The trauma registry included all trauma activations meeting institutional registry inclusion criteria, including blunt, penetrating, and burn injuries. A total of 8947 trauma patients from 2011–2022 were included in this study.
Strategic Planning and Implementation Timeline
Initiatives to pursue Level I designation formally began in 2019 through roundtable discussions with key stakeholders. These discussions assessed the current capabilities of the Level II trauma center and led to a structured needs assessment.
Patient volume, particularly the number of cases with ISS ≥16, was identified as a preliminary criterion for Level I eligibility. A retrospective review of trauma volumes from 2011–2022 was conducted, with particular focus on the 2019–2022 period to assess recent trends.
As projections suggested that ACS Level I volume thresholds could be met by 2025, a comprehensive gap analysis was performed using the Golden et al (2017) framework.17 The analysis mapped existing trauma program resources against ACS Resources for Optimal Care of the Injured Patient standards. The process identified four domains requiring development prior to verification, specifically four key areas for improvement (Table 1): (a) patient volumes; (b) a dedicated SICU; (c) a surgical residency training program; and (d) trauma-focused research.
Table 1 Rural Level I Development Framework: A Gap Analysis of High-Priority Facility Level I Criteria
To address these gaps, the trauma program implemented Rolling Action Item Log (RAIL) plans to define objectives, assign responsibilities, and monitor progress toward ACS Level I readiness.
Trauma Program Development Initiatives
In addition to infrastructure development, the trauma program implemented several organizational and clinical process improvements during the study period. These included expansion of trauma performance improvement activities, standardized trauma activation criteria, multidisciplinary trauma review processes, enhanced critical care coverage, and ongoing refinement of transfer and triage protocols. Although the present analysis was not designed to evaluate the independent effects of these initiatives, they likely contributed to overall maturation of the trauma program and improved system readiness for ACS Level I verification.
Measures
Demographic and clinical data collected included age, sex, and initial ISS, derived from patient charts and trauma flowsheets. Outcomes of interest included in-hospital mortality and length of stay.
Transfer distances were calculated using road mileage to reflect realistic travel barriers, accounting for impassable geographic features.
Statistical Analysis
All analyses were performed using R Studio 4.4.2 (R Foundation for Statistical Computing, Vienna, Austria). Demographic variables were presented by time intervals, stratified into four-time intervals: 2011–2013, 2014–2016, 2017–2019, and 2020–2022. Categorical variables were summarized using percentages, whereas means and 95% confidence intervals were used to summarize continuous variables (means consisting of less than five had variance expressed as ± standard deviation). For categorical variables, proportions were compared using chi-square goodness of fit with correction relative to the 2020–2022 period. One way ANOVA tests were used to compare quantitative variables with a post-hoc Dunnett’s multiple comparison test relative to 2020–2022 period. All p values less than 0.05 were considered statistically significant.
Results
Gap Analysis and Implementation Outcomes
A structured gap analysis (Table 1) identified four priority domains: (a) patient volumes, (b) a dedicated Surgical Intensive Care Unit (SICU), (c) a surgical residency program, and (d) trauma-focused research. Each area showed critical deficiencies, prompting targeted interventions.
Patient Volume
Initially, the facility did not meet ACS Level I volume thresholds, specifically 1200 trauma admissions or 240 severely injured patients (ISS ≥16), annually. Interventions involved regional outreach and registry improvements aligned with projected population and tourism growth. By 2023, while total admissions remained below 1200, the facility surpassed the 240 severely injured patient benchmark.
Surgical Intensive Care Unit (SICU)
Previously, trauma and emergent general surgery patients were co-managed without a dedicated SICU. In 2020, a dedicated SICU service was established, staffed by board-certified surgical critical care providers. Initially, night coverage involved Medical ICU (MICU) teams under surgical critical care oversight, later replaced by full SICU staffing with an additional critical care surgeon. Further restructuring included repurposing MICU rooms to support this transition.
Residency Program
The facility lacked a surgical residency program at baseline. A phased development plan established an on-site graduate medical education (GME) team, secured academic partnerships, and completed accreditation steps. In 2021, Postgraduate Year 4 (PGY-4) residents began rotations, and across the next two years six residents participated. Partner institutions have since shown interest in expanding their participation.
Research Infrastructure
Trauma research capacity was originally limited, with minimal staffing and support. Initial efforts included launching focused projects and hiring a research coordinator and a dedicated research nurse. The strategy emphasized high-yield topics to support ACS compliance, with continued success reliant upon physician and nursing engagement.
Demographic Trends
Between 2011 and 2022, 8947 trauma patients were treated, and subsequently divided into four intervals: 2011–2013 (n=1590), 2014–2016 (n=1764), 2017–2019 (n=2155), and 2020–2022 (n=3438) (Table 2).
Table 2 Trauma Patient Demographics Across Twelve Years
Patient Demographics
The trauma population aged significantly over time, with mean age rising from 42.6 to 51.8 years (p<0.0001). Pediatric cases (≤17 years) declined from 11.8% to 8.6%, while geriatric cases (≥65 years) nearly doubled from 19.8% to 37.1% (p<0.0001). Adult cases (18–64 years) decreased proportionally. Female patient cases increased from 33.3% to 41.2% (p<0.0001). Racial distribution remained stable, with White patients comprising ~78% throughout the study (p=0.4692).
Substance Use
Ethanol use increased from 18.0% to 22.8% (p<0.0001), while the average blood alcohol concentration (BAC) among positive patients declined from 208.6 to 168.4 mg/dL (p<0.0001).
Clinical Characteristics and Outcomes
Mechanism of Injury
Blunt trauma remained the predominant mechanism of injury throughout the study period, accounting for more than 90% of all admissions without significant temporal change (p=0.5098). Penetrating injuries and burns represented only a small proportion of cases but demonstrated modest variation over time (Table 3).
Table 3 Trauma Patient Clinical Trends Across Twelve Years
Injury Severity and Outcomes
Mean ISS peaked at 11.12 in 2014–2016, then declined to 9.7 by 2020–2022 (p<0.0001). Hospital mortality remained stable throughout the study period (3.3–4.0%, p=0.5355). However, the ISS among patients who died declined significantly from 35.1 to 22.5 (p<0.0001), coinciding with a significant increase in the elderly trauma population. Hospital length of stay increased from 4.49 to 5.11 days (p=0.0086).
ICU admissions peaked at 41.0% in 2017–2019 before declining to 22.6% (p<0.0001). ICU length of stay rose to 5.25 days, with ICU patient ISS increasing to 17.9, indicating higher acuity in those admitted.
Transfers and Transport
Interfacility transfer rates peaked at 47.1% in 2014–2016 but fell to 39.3% by 2020–2022 (p<0.0001). Transfer distance remained stable (~163-171 miles, p=0.3346).
Rotor wing transport increased from 9.7% to 15.1% (p<0.0001), while fixed wing use declined from 45.1% to 39.3% (p=0.0075). Ground transport showed minor fluctuations, decreasing slightly overall (p<0.0001). Other modes of transport remained minimal and stable (p=0.1445).
Transfers-Out
Annual transfers-out for higher or more appropriate care, remained stable (~10-13 per year; p=0.5381), but the proportion relative to total patients fell significantly from 2.8% to 1.1% (p=0.0372), with the sharpest decline between 2017–2019 and 2020–2022 (Figure 1 and Table 4). Despite the fluctuation in raw transfer numbers, transfers out represented a decreasing proportion of total patient volume across all intervals.
Table 4 Trauma Patient Transfers Out from the Facility for Higher-Level Care and Proportion of Total Trauma Admissions Across Twelve Years
Figure 1 Trauma Patient Transfers Out from the Facility for Higher-level Care and Proportion of Total Trauma Admissions, 2011–2022. Annual percentage of trauma patients transferred out of the facility relative to total trauma admissions and the proportional contribution of the major referral reasons. Error bars are standard deviation.
Discussion
To our knowledge, this is among the first longitudinal descriptions of organizational, workforce, research, and critical care infrastructure changes associated with ACS Level I verification in a rural trauma center serving a multistate frontier region. This study highlights the strategic transformation of a rural trauma center pursuing ACS-Committee on Trauma (COT) Level I designation.2 Through structured gap analysis and targeted improvements, measurable progress was achieved in domains specifically identified through an ACS Level I readiness assessment, and the institution subsequently achieved ACS Level I verification in 2023.
Meeting Volume Criteria in a Rural Setting
Though initially below ACS thresholds, the center met the severely injured patient (ISS) ≥16) benchmark by 2023. This was supported by improved ISS data accuracy, registry audits, and regional outreach. Growth in population and tourism18 likely contributed, highlighting that rural centers can align with community trends to meet volume targets without artificial inflation. A declining proportion of transfers-out further indicates enhanced local capacity for high-acuity care.
Development of a Dedicated Surgical ICU
Creation of a dedicated surgeon-directed SICU represented a major organizational change intended to meet ACS standards and expand local critical care capability.19 Transitioning from MICU night coverage to consistent trauma-led staffing, supported by an additional surgical intensivist, improved management of complex cases. The observed increase in ICU LOS and injury severity demonstrates an increase in complexity, and the restructuring is consistent with findings linking dedicated SICUs to improved outcomes and reduced transfers out from the facility.20,21
Building a Rural Academic Pipeline
Launching a surgical residency track marked a major advance, integrating PGY-4 residents into trauma care and laying groundwork for program expansion. GME leadership and academic partnerships enabled this transition. Prior studies have shown that resident involvement can enhance clinical outcomes22 and support long-term recruitment in underserved areas.23 In our residency track, although the program duration was limited, 66.7% of graduates are currently practicing as general surgeons, and 33.3% are localized to rural states. These findings suggest that rural centers can successfully develop and sustain training programs through phased implementation and also strong institutional support.
Laying the Foundation for Trauma Research
Establishing a trauma research program remains a challenge, especially in rural settings where infrastructure is limited. Embedding researchers within rural communities and fostering relationships with both patients and healthcare providers has demonstrated long-term benefits.24 Early project initiation and strategic recruitment of research staff have laid a foundation for sustained scholarly output, in line with ACS Level I expectations. Continued clinician and nursing engagement will be essential to maintain momentum,25 particularly given the workload-academic balance, issues common in rural systems.26 However, rural trauma care is an under-researched field, making it an ideal area of focus for the institution to develop expertise and produce publications.
Collectively, these initiatives addressed the principal organizational deficiencies identified during the initial ACS readiness GAP assessment and culminated in successful ACS Level I verification following external review in 2023.
Shifting Demographics and Injury Patterns
The trauma population served by this facility has aged significantly over the past decade, mirroring national trends.27 Geriatric patients now account for over one-third of trauma admissions, necessitating tailored clinical pathways for injury prevention, ICU management, and rehabilitation.28 Simultaneously, pediatric trauma declined, suggesting a need to reassess pediatric-specific readiness in a center increasingly focused on adult and elderly populations. The rise in ethanol prevalence, despite declining mean BAC levels, may indicate a broader public health concern around alcohol use and injury risk, albeit at a lower severity.
While mean ISS and mortality-associated ISS declined, mortality rates remained stable This apparent paradox may reflect increased mortality in less severely injured elderly patients, improved triage, earlier interventions,29 or shifts in case mix30 rather than changes in trauma severity alone. Notably, ICU admission rates decreased in recent years, yet those admitted had significantly higher acuity, as evidenced by rising ISS and ICU length of stay. This suggests more targeted ICU utilization, consistent with maturing trauma systems.29
Clinical Implications of Injury Patterns
Throughout the study period, blunt trauma consistently accounted for more than 90% of injuries, reflecting the epidemiology of trauma in rural and frontier regions. Unlike many urban Level I trauma centers, where penetrating trauma represents a larger proportion of major injuries, the institution primarily manages injuries resulting from motor vehicle collisions, falls, agricultural accidents, and recreational trauma. This injury profile has important implications for trauma system development because blunt trauma frequently requires prolonged multidisciplinary management, advanced imaging, orthopedic and neurosurgical expertise, critical care, and rehabilitation rather than immediate operative hemorrhage control. Accordingly, the predominance of blunt trauma likely shaped the resources required for Level I readiness, supporting investments in surgeon-directed critical care, multidisciplinary ICU services, specialty coverage, and coordinated rehabilitation pathways.
The progressive aging of the trauma population likely contributed to the observed decline in mortality-associated ISS. Elderly patients often experience substantial morbidity and mortality following injuries that would be considered moderate in younger adults because of frailty, anticoagulant use, and multiple comorbidities.27
Burn injuries represented only a small proportion of trauma activations and therefore had minimal influence on overall trauma system planning. Nevertheless, inclusion of burn patients within the registry reflects the comprehensive regional role of the institution and underscores the importance of maintaining transfer relationships with specialized burn centers when appropriate. Consequently, trauma centers serving rural populations should anticipate increasing demand for geriatric-specific trauma pathways, multidisciplinary rehabilitation, and critical care expertise.
These findings suggest that rural Level I trauma readiness extends beyond meeting ACS verification criteria and must also incorporate clinical resources tailored to the predominant injury mechanisms and demographic characteristics of the population served.
Evolving Transport and Transfer Patterns
Transport modalities evolved substantially, with increased rotor wing utilization and declining fixed-wing use. These patterns reflect improved prehospital coordination, weather-related access patterns, and/or cost considerations. The consistent distance between injury and definitive care over time affirms the regional role of the facility within a large rural catchment area.
The reduction in transfers-out may reflect increasing institutional readiness and expanding local treatment capacity, although this observational study cannot determine whether the decline resulted directly from Level I preparation activities or other concurrent organizational changes. As trauma centers mature, reduced reliance on tertiary referrals has been associated with higher system efficiency and reduced time to definitive care.31
Implications for Other Rural Trauma Centers
The findings of this study have important implications for rural trauma centers seeking to expand capabilities and pursue higher levels of trauma verification. Achieving Level I trauma center requirements in rural settings appears feasible through deliberate system development, robust trauma registry practices, and strategic alignment with regional population and referral trends. Investments in dedicated, surgeon-directed critical care infrastructure may enhance a center’s ability to manage increasingly complex trauma patients locally, reducing reliance on tertiary referrals and improving access to definitive care. Similarly, development of rural graduate medical education programs may provide a sustainable workforce strategy by strengthening recruitment pipelines and promoting retention of surgeons in underserved regions. Establishing trauma research capacity, through incremental investments in personnel and infrastructure, can support verification requirements while generating evidence relevant to rural populations that remain underrepresented in trauma research. Furthermore, reductions in transfers-out and evolving transport patterns suggest that strengthening regional coordination and transfer networks may improve system efficiency and local treatment capacity across large geographic catchment areas.
These findings should be interpreted within the broader context of substantial advances in trauma care that occurred nationally during the study period.32 Improvements in trauma resuscitation,33 critical care, imaging technology, prehospital triage,34 geriatric trauma management,35 and regional trauma system development likely influenced patient outcomes independent of institutional efforts toward Level I verification. Consequently, observed changes in patient characteristics, transfer patterns, ICU utilization, and clinical outcomes cannot be attributed solely to local initiatives. Rather, this study describes how a rural trauma center adapted to and leveraged evolving best practices while pursuing system maturation. Collectively, the findings suggest that rural trauma centers can successfully advance toward higher levels of trauma system maturity through phased, data-driven investments in clinical infrastructure, workforce development, research capacity, and regional partnerships, while simultaneously incorporating broader innovations in trauma care delivery.
Strengths
This study has several notable strengths. First, it provides a longitudinal 12-year evaluation of trauma system development preceding ACS Level I verification, allowing assessment of organizational and clinical trends over an extended period. Second, the study examines a rural trauma center serving a large multistate frontier region, a setting that is underrepresented in trauma literature. Third, the analysis incorporates multiple domains of trauma center maturation, including workforce development, critical care infrastructure, research capacity, patient demographics, and transfer patterns, providing a comprehensive view of Level I readiness. Finally, the use of a prospectively maintained trauma registry allowed evaluation of nearly 9000 trauma patients and facilitated objective assessment of changes occurring during the center’s progression toward ACS Level I verification.
Future Studies
Future multicenter studies are needed to evaluate whether the developmental framework described in this study can be successfully replicated in other rural and frontier trauma centers. Comparative investigations examining centers that achieve Level I verification versus those that do not, may help identify the most influential organizational, workforce, and infrastructure factors associated with successful advancement. In addition, cost-effectiveness analyses are needed to better understand the financial investment required for rural trauma system maturation.
Limitations
Several limitations must be acknowledged. First, this is a single-center retrospective analysis, limiting generalizability. Second, ISS calculations and registry data are inherently subject to variation, despite audit safeguards. Third, some metrics of trauma center readiness, such as timeliness of subspecialty response, quality of multidisciplinary care, and educational outcomes, were not captured in this dataset. Fourth, we were unable to account for secular changes in trauma care practices occurring nationally during the study period, and therefore causal attribution of observed trends to Level I preparation activities alone cannot be established. Lastly, while progress toward Level I designation is evident, the long-term sustainability of these gains remains to be evaluated. Because this was an observational single-center study without a contemporaneous comparison group, causality cannot be inferred. Multiple institutional developments occurred concurrently, including hospital expansion, workforce growth, critical care restructuring, educational program development, and trauma system maturation. Consequently, it is not possible to determine the relative contribution of ACS Level I preparation activities versus other organizational changes to the observed trends. The findings should therefore be interpreted as associations occurring during the center’s transition rather than direct effects of designation-related initiatives.
Conclusion
The observed changes in patient demographics, transfer patterns, ICU utilization, and institutional capabilities occurred concurrently with the center’s progression toward ACS Level I verification and illustrate the complexity of trauma system development in rural settings. Major organizational developments included surpassing the ISS volume threshold, establishing a dedicated SICU service, launching a surgical residency track, and initiating trauma research infrastructure. These developments occurred alongside important clinical changes within the trauma population, including a growing proportion of geriatric patients, persistent predominance of blunt trauma, increasing injury severity among ICU patients, and evolving transport and transfer patterns. Together, these findings demonstrate that successful trauma system maturation in rural settings requires both organizational development and adaptation to changing clinical demands. This study provides a longitudinal perspective on a rural trauma center advancing its system despite aging populations and limited resources, while offering a replicable roadmap for other rural institutions seeking to enhance trauma care within the challenges of rural healthcare.
Disclosure
All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. All the authors declare that there is no conflict of interest in this work.
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