Flagship response: a descriptive analysis of definitive surgical care at the Walter Reed National Military Medical Center following the Afghanistan withdrawal

Abstract

Objectives

We descriptively analyzed the trauma care outcomes of combat casualties arriving at the Walter Reed National Military Medical Center (WRNMMC) following the 2021 Afghanistan withdrawal as part of process improvement (PI) initiatives and quality assurance.

Methods

A retrospective review of casualty records within the trauma registry at WRNMMC was conducted. The review included all patients who required definitive surgical intervention or critical care at WRNMMC from injuries sustained during the Afghanistan withdrawal. Data abstraction involved a detailed review of electronic medical records to document patient demographics, injury mechanisms, Injury Severity Scores (ISSs), operative reports, perioperative complications, and outcomes.

Results

A total of 50 casualties were received at WRNMMC after the Afghanistan withdrawal, including 17 US military service members and 33 Afghan evacuees (20 adults and 13 pediatric). The mean ISS for US service members was 16.3±14.3. The mean ISS of Afghan evacuees was 10.7±6.1 for adults and 16.6±13.3 for pediatric evacuees. Polytrauma was common, with a majority of casualties sustaining injuries to multiple body regions. A total of 234 injuries were seen, with an average of 4.68±3.8 injuries per casualty. 264 operations were performed, averaging 5.2±5.6 per casualty. 23 postsurgical complications occurred in 10 casualties. 28 PI filters were initiated on 22 casualties. Caring for the casualties required multidisciplinary cooperation led by the trauma and acute care surgery service.

Conclusion

The trauma care provided at WRNMMC following the Afghanistan withdrawal demonstrated institutional readiness and effective multidisciplinary coordination, but with a sizable burden of postoperative complications and PI filters. Lessons from this experience highlight the importance of continuous PI to optimize care delivery and outcomes, and underscore the need to sustain WRNMMC and strengthen other casualty-receiving Military Treatment Facilities to preserve trauma care readiness for future conflict.

Level of evidence

Therapeutic/care management; level V.

WHAT IS ALREADY KNOWN ON THIS TOPIC

• The 2021 Hamid Karzai International Airport attack during the Afghanistan withdrawal generated a mass casualty event managed across a mature military trauma system spanning forward surgical care, aeromedical evacuation, Landstuhl Regional Medical Center, and stateside definitive care. Prior reports have described the in-theater and en route medical response, as well as broader lessons regarding combat casualty care during the initial event and evacuation. However, there has been limited description of the definitive surgical, critical care, and multidisciplinary outcomes of casualties after arrival at Walter Reed National Military Medical Center (WRNMMC), the principal Role 4 combat casualty receiving facility in the Military Health System (MHS). This study was needed to characterize the downstream workload, evaluate institutional trauma readiness, and identify opportunities for process improvement during a high-acuity surge event.

WHAT THIS STUDY ADDS

• This study provides a descriptive analysis of 50 casualties transferred to WRNMMC following the Afghanistan withdrawal, including US service members and Afghan adult and pediatric evacuees. It demonstrates that WRNMMC successfully absorbed a large combat casualty surge and delivered complex definitive surgical and critical care without in-hospital mortality, despite substantial injury burden, repeated operative interventions, and prolonged length of stay. The findings demonstrate the important role of WRNMMC as the principal receiving center for definitive combat casualty care, and highlight the importance of multidisciplinary coordination, trauma registry infrastructure, and formal processes in identifying system vulnerabilities and driving institutional adaptation.

HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY

• These findings support sustained investment in military trauma readiness at Role 4 facilities, including multidisciplinary staffing, trauma systems infrastructure, registry-based process improvement, and the preservation of combat casualty care expertise during periods of low operational volume. The study also reinforces the need for stronger military-civilian partnerships, improved pediatric trauma pathways, enhanced critical care capabilities, and standardized patient identification processes for future multinational or humanitarian casualty events. At a policy level, the experience argues for preserving WRNMMC’s Flagship casualty-receiving role and strengthening the broader MHS trauma system to ensure preparedness for future mass casualty incidents and large-scale combat operations.

Introduction

The exit of US service members from Afghanistan in the summer of 2021 culminated in the drawdown of the Global War on Terrorism (GWOT), a military conflict that evolved into the longest war in American history.¹ Operation Allies Refuge, a mission supported by several thousand rapidly deployed US troops and the US State Department, was charged with evacuating international personnel and Afghan nationals in response to the deteriorating humanitarian situation in the capital city of Kabul.^{2 3} The task force also included US and allied military surgical units located at two medical facilities at the Hamid Karzai International Airport (HKIA) in Kabul. Before the final departure of US service members and evacuees from Afghanistan, a suicide bombing at Abbey Gate triggered a mass casualty incident. This resulted in hundreds of casualties with complex blast, penetrating, and multisystem traumatic injuries.⁴

The surgical teams deployed at HKIA delivered care during the event under significant logistical and operational constraints, including equipment and supply limitations, deteriorating security conditions, and a rapidly evolving humanitarian crisis at the airport, which also complicated the aeromedical evacuation chain.⁵ The critically ill and injured patients sustained at HKIA were treated initially and then medically evacuated from Afghanistan via US Transportation Command and Critical Care Air Transport Teams (CCATT) to Landstuhl Regional Medical Center, Germany, and then ultimately back to the continental US, where they reached Walter Reed National Military Medical Center (WRNMMC) in Bethesda, Maryland, for definitive surgical care.

Walter Reed has re-verified as an ACS level 2 trauma center and serves as the principal combat casualty care reception military treatment facility (MTF) within the Military Health System (MHS). Throughout the GWOT, WRNMMC served as the primary destination for definitive surgical care, rehabilitation, and functional restoration for combat-injured service members. Colloquially designated as the ‘Flagship’ of the MHS by military medical leaders, WRNMMC is a 250-bed academic-tertiary care center with trauma, general, and complex subspecialty surgical support (ie, orthopedics, neurosurgery, plastic, otolaryngology) that has consistently maintained the capability to receive acutely injured casualties from overseas theaters of operation within 48 hours of wounding.⁶ During periods of high operational tempo, such as the mid-2000s surge, WRNMMC functioned as a vital link in the continuum of military trauma care, prepared to manage the full spectrum of combat injuries. Overall, during GWOT, WRNMMC and its legacy institutions, the National Naval Medical Center (NNMC) and Walter Reed Army Medical Center, treated over 10,000 combat casualties returning from overseas.

This same posture of readiness was evident during the evacuation from HKIA, when WRNMMC once again mobilized to receive and manage a sudden influx of severely injured casualties.⁷ Although the overall volume of combat casualties had steadily declined in the later years of GWOT, culminating in a prolonged period of reduced operational trauma, depicting the nadir in the ‘Walker Dip’, the HKIA incident represented the highest volume of combat casualties received at WRNMMC in over a decade.⁸

All casualties transferred to WRNMMC had undergone damage control resuscitation and initial operative management at HKIA or LRMC and had survived at least 48 hours before arrival. Accordingly, WRNMMC functioned primarily as the tertiary referral center, providing definitive and reconstructive surgical care, critical care, and coordinated multidisciplinary management following initial stabilization. The majority of injuries seen at WRNMMC from HKIA were the result of complex blast mechanisms and high-velocity weapons, rarely, if ever, encountered in civilian trauma centers.

For context, large-scale civilian mass-casualty incidents have demonstrated substantially higher immediate operative demand at receiving centers, including the 2017 mass shooting in Las Vegas, the 2013 Boston Marathon bombing, and the 2016 attack at the Pulse Nightclub.9,11 In contrast, the clinical workload at WRNMMC was dominated by definitive surgical management and longitudinal recovery following prior life-saving and limb-saving interventions.

Likewise, although the foreign national status of the evacuated Afghan patients did not substantially alter operative or clinical decision-making, it introduced additional disposition, repatriation, and interagency coordination requirements, increasing care-coordination complexity beyond that typically encountered in civilian trauma centers managing domestic mass-casualty events. Notably, however, it was the first time WRNMMC was required to simultaneously deliver multidisciplinary care to US service members and to evacuated foreign nationals flown to the US from another country, a demand no US military or civilian hospital had previously faced.

The medical response to the HKIA attack occurred within the context of a mature, globally integrated military trauma system that had been refined over two decades of sustained combat operations.¹² Rather than representing a singular stress test of the MHS, the HKIA response demonstrated the continued adaptability and resilience of an established continuum of care operating during a period of force and infrastructure drawdown, when in-theater evacuation networks were reduced and fixed facilities were no longer operational.

Care of the wounded relied on coordinated performance across multiple echelons, including forward surgical teams, aeromedical evacuation, CCATT, and Landstuhl Regional Medical Center, before transfer to stateside definitive care at WRNMMC.¹³ This distributed, multinational response highlights the effectiveness of a global trauma system capable of sustaining coordinated care across several continents despite constrained theater resources.

Within this broader system, WRNMMC served as the principal stateside tertiary referral and definitive care center during the evacuation surge. Its role was essential in receiving stabilized casualties and providing complex surgical and multidisciplinary care; however, this capability depended on the successful performance and integration of the full trauma system before arrival. The HKIA experience, therefore, reinforces the importance of preserving WRNMMC’s advanced clinical and operational readiness and simultaneously underscores that military trauma readiness is inherently system-dependent and contingent on sustained interoperability, coordination, and capacity across the entire joint and coalition continuum of care.

Recognizing HKIA’s operational and clinical significance, a deliberate effort was made to systematically review and extract lessons from WRNMMC’s response. HKIA served as a real-time surge of military trauma protocols, multidisciplinary coordination, and system-level resilience. A structured quality assurance (QA) and process improvement (PI) initiative was undertaken to formally assess patient-level outcomes and system-wide functionality during this mass casualty event.

As part of this PI initiative, we descriptively analyzed the outcomes of casualties from HKIA who arrived at WRNMMC for definitive surgical care. The analysis sought to evaluate the effectiveness of surgical and critical care services provided to HKIA casualties and assessing the system’s overall readiness and adaptability to a large-scale casualty surge. This comprehensive approach ensured not only the evaluation of patient outcomes but also the enhancement of WRNMMC’s readiness for future surge events and the institutionalization of lessons learned. This manuscript aims to serve as a critical bridge between past experience and future readiness, ensuring that the hard-won lessons from GWOT and HKIA are preserved, applied, and used to strengthen the MHS’s preparedness for future combat casualty care demands.

Methods

This study was conducted as a PI initiative within WRNMMC to evaluate trauma care processes following the HKIA attack during the Afghanistan withdrawal. The review complied with institutional PI oversight and patient privacy requirements, and all data were extracted from the WRNMMC trauma registry and institutional medical records in accordance with Health Insurance Portability and Accountability Act standards using deidentified study files. The protocol was reviewed and approved by the Uniformed Services University and WRNMMC Institutional Review Board, which determined that the activity met criteria for a single-center retrospective review of existing data conducted in support of quality and performance improvement, with a waiver of informed consent. The Equator Guidelines for Standards for Reporting Qualitative Research Checklist was used (Supplementary Digital Content).

Data were abstracted manually from the electronic medical record (EMR; MHS GENESIS and legacy systems) and the Department of Defense Trauma Registry (DoDTR) and recorded in a standardized spreadsheet (Microsoft Excel, Microsoft, Redmond, WA). Data abstraction was performed by members of the WRNMMC trauma program, including the Trauma Program Manager and trained trauma data extractors, all of whom were registered nurses with experience in trauma registry data collection and PI processes. Abstracted data were cross-referenced between the EMR and trauma registry to ensure completeness and accuracy. Data quality was further supported through the WRNMMC trauma performance improvement and patient safety program, which includes routine review by the trauma program manager, trauma data extractors, trauma medical director, and the trauma performance improvement and patient safety program committee during regularly scheduled multidisciplinary performance improvement meetings. Discrepancies were resolved by consensus review of the source medical record.

The trauma and emergency general surgery PI program at WRNMMC provided the structural backbone for this review, drawing on well-established processes matured throughout GWOT.^{14 15} A three-tiered review system was employed to ensure comprehensive evaluation and continuous improvement. Initial reviews were conducted by the PI coordinator, with secondary reviews presented at weekly departmental morbidity and mortality conferences. A tertiary review process focused on closing feedback loops and implementing corrective actions to address identified issues. The program emphasized standardized tracking of PI events, including unplanned returns to the operating room (OR, delayed diagnoses, readmissions, and morbidity/mortality. Operative and postoperative outcomes were carefully examined alongside transitions in care from HKIA to WRNMMC.

Results

HKIA-Landstuhl Regional Medical Center

The attack at HKIA on August 26, 2021, killed at least 170 Afghans and 13 US service members, leaving hundreds more wounded.¹⁶ In the immediate aftermath, US military surgical teams deployed to HKIA delivered over 15 hours of continuous combat casualty care.⁵ During this time, the surgical teams managed 63 patients, of whom 12 required emergency surgical interventions.⁵

Once stabilized, many of these patients were evacuated via fixed-wing military air transport with CCAT and Aeromedical Evacuation Teams to Landstuhl Regional Medical Center (LRMC) in Germany for further critical, perioperative, or surgical care. On arrival at LRMC, 14 major operations were performed, including a craniotomy, exploration of a bilateral anterior thoracotomy, open abdominal explorations, amputation revisions, and multiple debridements of blast wounds.⁵ In the 48 hours after the explosion, 33 patients with traumatic injuries were admitted. Overall, LRMC received 50 patients, during which 65 surgical operations were completed.⁵

Walter Reed National Military Medical Center

Patient flow and demographics

From August 27, 2021, to September 17, 2021, WRNMMC received 50 combat casualties transferred from LRMC after the HKIA attack for definitive surgical care (figure 1), representing a surge event for the institution. In anticipation of incoming patients, WRNMMC implemented an all-hands response, mobilizing military healthcare personnel across all clinical services, as well as administrative and liaison staff, to support sustained operations. Close coordination with transport teams, multidisciplinary surgical services, and the blood bank was maintained throughout the event, with timely communication regarding patient movement, critical care requirements, and anticipated transfusion needs. This facilitated proactive bed allocation, staffing adjustments, and resource planning across the institution and the National Capital Region (NCR). Blood product availability remained sufficient to meet clinical demand, with no supply shortages encountered.

Figure 1. Date and number of combat casualties received at the Walter Reed National Military Medical Center.

Of the 50 combat casualties received at WRNMMC, 17 were US military service members, and 33 were Afghan evacuees, including 20 adults and 13 pediatric patients. The majority (94%) of US military casualties were male. The mean age of US military casualties was 22.5±3.4 years, with a mean Injury Severity Score (ISS) of 16.3±14.3. Of the adult Afghan evacuee casualties, the majority (85%) were male. The mean age of the adult Afghan evacuees was 33.8±11.2 years, with a mean ISS of 10.7±6.1. Of the pediatric Afghan evacuees, the majority were male (53%). The mean age of the pediatric Afghan evacuee casualties was 8.1±4.7, with a mean ISS of 16.6±13.3 (table 1).

Table 1. Patient demographics.

	US (n=17)	Afghan adults (n=20)	Afghan pediatric (n=13)
Gender
Male	16 (94%)	17 (85%)	7 (53%)
Female	1 (6%)	3 (15%)	6 (47%)
Demographics (mean±SD)
Age	22.5±3.4	33.8±11.2	8.1±4.7
ISS	16.3±14.3	10.7±6.1	16.6±13.3

ISS, Injury Severity Score.

A total of 16 patients (32%) required treatment in the intensive care unit (ICU), with 11 admitted to the Surgical ICU and five to the Pediatric ICU (PICU). The remaining 34 patients (68%) received care in the inpatient ward. Patients requiring ICU admission accounted for 67 cumulative ICU days, including 22 ventilator days, with a total of 53 units of blood products transfused. Furthermore, 45 of 50 patients were primary admissions to the trauma and acute care surgery (TACS) service. In contrast, one patient was admitted to the internal medicine service, one to the pediatric service, one to the PICU, and one to the vascular surgery service.

Injury patterns and operative care

The distinct injury patterns seen from the Afghanistan withdrawal were similar to those observed over the last 20 years of combat during GWOT, a result of improvised explosive devices and small arms fire. Of the 50 casualties, 37 sustained primary blast injuries from the Abbey Gate attack, 11 sustained gunshot wounds, and two sustained other non-combat traumatic injuries (burns unrelated to the blast and physical altercation injuries). Polytrauma was common, with 43 of 50 casualties sustaining more than one injury. A total of 234 injuries were observed among the 50 casualties (figure 2). The most common injury patterns were soft-tissue extremity injuries (n=55) and extremity fractures (n=44), accounting for almost half of all injuries (42.3%). The average number of injuries per casualty was 4.68±3.8.

Figure 2. Number and types of injuries sustained.

The observed injury patterns were categorized into orthopedic trauma (25%), head and neck trauma (20%), thoracic trauma (11%), abdominal trauma (7%), and other trauma (37%) (figure 3a). Orthopedic injuries included extremity fractures (n=44), spinal fractures (n=10), and traumatic extremity amputations (n=5). Head and neck injuries resulted in skull/facial fractures (n=16), severe traumatic brain injuries (diffuse axonal injuries) (n=9), face/head wounds (n=8), intracranial hemorrhage (n=6), orbital injuries (n=6), and a sinus thrombus (n=1). Thoracic injuries included lung contusions (n=10), rib fractures (n=7), pneumothorax/hemothorax (n=6), acute respiratory distress syndrome (n=1), pulmonary embolism (n=1), and esophageal injury (n=1). Other injuries comprised mainly extremity injuries, excluding orthopedic injuries, and were broken down into extremity soft tissue injuries (n=55), peripheral vascular injury (n=15), urogenital injuries (n=7), non-extremity soft tissue injury (n=4), burns (n=3), and extremity nerve injuries (n=2) (figure 3b).

Figure 3. Breakdown of all traumatic injuries; breakdown of traumatic injuries by head and neck, chest, orthopedic, and other trauma. HEENT, Head, Eyes,Ears, Nose, and Throat; TBI, Traumatic Brain Injury.

Nearly 78% (n=39) of casualties admitted to WRNMMC underwent an operation during their hospital stay. A total of 264 operations were performed during this time (figure 4). The average operations per patient were 5.2±5.6. Extremity wound irrigation and debridement, with the placement of vacuum-assisted wound closure devices, amounted to 92 (35%) of the operations. Chest or abdominal wound irrigation and debridement, with the placement of vacuum-assisted wound closure devices, represented 35 (13%) of procedures. Other wound management operations, including delayed primary closure, skin grafting, and myocutaneous flaps, resulted in 25, nine, and three operations, respectively.

Figure 4. Number and types of operations performed. CRPP, closed reduction percutaneous pinning; ORIF, open reduction and internal fixation; PEG, percutaneous endoscopic gastrostomy; IR, Interventional Radiology; VATS, video-assisted thoracoscopic surgery.

Orthopedic operations included external fixation placement or removal (n=25) and open reduction and internal fixation/closed reduction percutaneous pinning (n=26). Abdominal laparotomies accounted for nine procedures, and peripheral vascular repairs resulted in seven. Less common procedures included microsurgery and nerve reconstruction (n=6), neurosurgery of the brain and spine (n=4, n=2), dental procedures (n=6), tracheostomy creation (n=4), exam/manipulation under anesthesia (n=4), video-assisted thoracoscopic surgery (n=1), bronchoscopy (n=1), laryngoscopy (n=1), percutaneous endoscopic gastrostomy tube placement (n=2), Interventional Radiology (IR) embolization (n=1), and an ophthalmic operation (n=1).

During this period, near-continuous OR utilization was maintained. Dedicated ORs were allocated for severely injured casualties and those requiring multiple procedures. To accommodate the influx of these casualties and OR use, some elective surgical cases were rescheduled later in the day or transferred to other military treatment facilities in the NCR, including Alexander T. Augusta Military Medical Center and Malcolm Grow Medical Clinics and Surgery Center. Despite this surge, normal inpatient operations were not disrupted at the hospital, a testament to the flexibility and dedication of the WRNMMC medical staff. WRNMMC successfully adapted to the increased demand without compromising care for our catchment area of active-duty service members, beneficiaries, and their families.

A notable case involved a complex polytrauma patient who sustained a massive pulmonary embolism complicated by acute respiratory distress syndrome. Understanding that the patient would need venoarterial extracorporeal membrane oxygenation (ECMO) support, the patient was transferred to a partnered local civilian hospital, as WRNMMC currently does not have a sustained ECMO service. The patient had a short stay at the partnered civilian hospital and returned to WRNMMC after being weaned off ECMO and decannulated, with the need for further surgical care.

A notable case involved a complex polytrauma patient who sustained a massive pulmonary embolism complicated by acute respiratory distress syndrome. Understanding that the patient would need venoarterial extracorporeal membrane oxygenation (VA-ECMO) support, the patient was transferred to a partnered local civilian hospital, as WRNMMC currently does not have a sustained ECMO service. The patient had a short stay at the partnered civilian hospital and returned to WRNMMC after being weaned off ECMO and decannulated, with the need for further surgical care.

Morbidity, complications, and PI

Every casualty from HKIA who received definitive surgical care at WRNMMC was discharged to a rehabilitation center or an outpatient setting. There was no in-hospital mortality.

A total of 23 complications occurred in 20% (n=10) of patients during their admission to WRNMMC. Complications were defined according to the American College of Surgeons Trauma Quality Improvement (ACS TQIP) criteria and included pressure ulcers (n=3), venous thromboembolism (VTE) (n=3), pneumonia (n=2), bacteremia (n=2), urinary tract infection (n=1), unplanned intubation (n=1), wound infection (n=1), acute respiratory failure (n=1), and major arrhythmia (n=1).¹⁷ Additional complications captured by the DoDTR included delirium (n=3), arterial thrombosis (n=1), pancreatitis (n=1), soft tissue infection (n=1), aspiration (n=1), and hypernatremia (n=1). Descriptions of these complications are depicted in online supplemental material 1.¹⁸

Additionally, 28 PI filters were initiated on 44% (n=22) of patients. These filters are based on the ACS TQIP and the Joint Trauma System’s Performance Improvement and Patient Safety Plan to refine patient-wide and hospital-wide QA.^{17 19} The most common PI filter included pediatric admissions (n=12), as many Afghan evacuees were pediatric patients. Other PI filters were medication delay/complication (n=3), unplanned return to the OR (n=3), missed injury (n=2), readmit to the hospital (n=1), admission to non-surgical service (n=1), readmitted to the ICU (n=2), hypoxia <90% oxygen saturation for greater than 5 min (n=1), and reintubation within 48 hours of extubation (n=1). These PI cases were discussed, analyzed, and resolved at a multidisciplinary care meeting, and all patients were treated in accordance with the standards of care. Descriptions of these PI filters are depicted in online supplemental material 2.

Disposition

The average hospital length of stay at WRNMMC for US service members was 12.3±8.7 days and 48.3±61.4 days for Afghan evacuees. All of the US military service members were discharged home or to an outpatient setting for rehabilitation. Although the ISS was not drastically different between the two groups, the Afghan nationals had a prolonged stay. This was primarily due to disposition issues, as discharge required the involvement of numerous external government agencies, including the Health and Human Services Office of Refugee Resettlement, U.S. Citizenship and Immigration Services, the Department of Homeland Security, the Department of State, and the US Public Health Service. The majority of Afghan evacuees were discharged to barracks on Naval Support Activity Bethesda, the installation where WRNMMC is located. Other patients were discharged home to family living in the USA, to the Afghan Refugee Facility, or to the Youth for Tomorrow shelter. Follow-up data were limited by several factors, including patient relocation, limited access to the installation, security restrictions, a contemporaneous transition to the EMR system, and loss to follow-up due to missed outpatient appointments.

Multidisciplinary care and video teleconference

A multidisciplinary approach was essential to the successful care of HKIA casualties, spanning the entire continuum from admission through discharge. Central to this effort was the TACS service, which has served as the backbone of trauma care at WRNMMC since its formal establishment during GWOT in 2015 as part of a broader trauma and emergency general surgery PI initiative. The TACS service, composed of an attending trauma/critical care surgeon, a chief resident, junior residents, and two interns, assumed primary responsibility for overseeing and integrating care across specialties. In response to the surge in patient volume, the team was temporarily reinforced with additional residents to meet clinical demands. The TACS service coordinated care across all involved subspecialties, including orthopedic surgery, vascular surgery, plastic surgery, neurosurgery, and otolaryngology (ENT).

Every patient also received ‘war consults’ that included evaluation by physical therapy, occupational therapy, nutrition, speech-language pathology, acute pain management, physical medicine and rehabilitation, psychiatry, ophthalmology, the traumatic brain injury team, audiology, ENT, and hospital dentistry. These ‘war consults’ ensured that no injuries (acute or chronic) were missed (such as fractured teeth and perforated eardrums), and each patient received complete medical care. The ‘war consult’ protocol was originally developed in the early 2000s at the former NNMC. At that time, surgical teams observed that certain injuries, particularly otologic and dental trauma, were being under-recognized during the initial phases of care. In response, a standardized consultation pathway was implemented to ensure systematic, protocol-driven evaluation of all returning casualties. Over time, the program expanded to include any evacuated injured service member requiring comprehensive postdeployment/post-injury medical care. Furthermore, during hospitalization, each patient was assigned a nurse case manager and a social worker, who were instrumental in coordinating discharge planning, rehabilitation needs, and longitudinal follow-up care across the multidisciplinary team.

In addition to the multidisciplinary care provided at WRNMMC, 24% (n=12) of patients were formally presented at the Joint Trauma System (JTS) weekly trauma case series via video teleconference. All patients (100%, n=50) underwent the JTS review process and were documented in the DoDTR. The JTS weekly trauma conference has served as a forum for discussing combat casualty cases since it was initiated during GWOT.²⁰ One of the objectives of the JTS is to ensure medical performance optimization, a data-driven process for coordination and feedback across every role in care (from the point of injury to the US MTF).^{21 22}

Discussion

WRNMMC was prepared to care for the service members and Afghan evacuees who sustained traumatic injuries during the HKIA attack. This readiness was the result of the WRNMMC military trauma program, developed and refined over the last two decades of GWOT, and the invaluable lessons learned during that time.

Clinical and definitive casualty care lessons

Over a 4-day period, WRNMMC received an influx of 35 casualties, including 14 patients on a single day. In total, 50 casualties were received over 3 weeks. All casualties were transported directly from the Joint Base Andrews flight line to WRNMMC in a near-simultaneous manner using ambulance busses for surgical ward-level casualties and Patient Evacuation Vehicles (PEVs), ICU-capable evacuation platforms, for the critically ill casualties. This approach enabled efficient group transport for non-ICU patients; however, ambulance busses have more limited advanced life support capabilities than traditional critical care ambulances, highlighting an important logistical triage consideration when transporting higher-acuity casualties via the limited number of PEVs. In response to lessons learned from the HKIA evacuation, WRNMMC subsequently received approval for and acquired two additional PEVs and another ambulance bus to enhance both critical care transport capability and overall patient movement capacity. Ultimately, the scale, acuity, and tempo of this surge event created substantial operational and clinical demands. This event exemplified the singularity of the HKIA-WRNMMC experience: a convergence of high-volume combat trauma, long-distance aeromedical evacuation, and the need for immediate multidisciplinary definitive surgical intervention.

US service members and Afghan evacuees injured in the HKIA attack sustained severe polytrauma, with ISSs averaging 16.3±14.3 and 10.7±6.1/16.6±13.3 (adults and pediatrics), respectively. Each patient had an average of 4.68 injuries, primarily affecting the extremities, followed by the thorax, abdomen, and head.^{23 24} These injury patterns, consistent with past military conflicts involving improvised explosive devices (IEDs) and small arms fire, required a multidisciplinary and subspecialized approach to definitive surgical care.^{25 26} Management was guided by established JTS clinical practice guidelines and institutional WRNMMC trauma protocols, developed and refined during the GWOT conflict to standardize the care of combat casualties.

WRNMMC managed a significant surgical workload, with 78% of patients requiring operative intervention and an average of 5.2 procedures per patient. Extremity wound care accounted for 35% of all procedures, alongside orthopedic operations, abdominal laparotomies, and vascular repairs, reflecting the complexity of these polytraumatic injuries. Despite the surge in demand, the hospital maintained continuous OR utilization without major disruption to elective operations, inpatient, or critical care services, demonstrating continued operational combat casualty and beneficiary readiness.

Patients faced prolonged recovery, with an average hospital stay of 36.8±53.4 days, influenced particularly by disposition challenges for Afghan evacuees. ICU care was required for 32% of patients. Although most casualties were admitted to general wards for extremity soft-tissue management, nearly one-third required higher-acuity monitoring, reflecting the perioperative complexity and resource coordination associated with definitive combat injury care.²⁷ The division of ICU care between adult and pediatric units highlighted the diverse patient demographics. However, the absence of a sustained on-site ECMO capability necessitated patient transfer, revealing a gap in advanced critical care resources. Fortunately, established partnerships with regional civilian hospitals helped mitigate this limitation during the HKIA response. Moving forward, WRNMMC must develop and maintain a sustained on-site ECMO capability to ensure timely access to advanced organ support systems, which is becoming increasingly used in trauma and combat casualty care.

Furthermore, although blast injuries may include associated burns, no patients in this cohort sustained burn injuries of sufficient severity to require transfer for specialized burn care. As WRNMMC is not a designated burn center, patients requiring advanced burn management are appropriately referred through established MHS burn referral pathways within the NCR. In contrast, minor or moderate burns can be managed locally by trauma, plastic, and orthopedic surgical teams with relevant burn experience or formal burn fellowship training.

Complications occurred in 20% of patients, with pressure ulcers, infections (pneumonia, bacteremia, soft tissue), and VTE being the most common. Although these rates are expected for a trauma cohort of this severity, they underscore the ongoing challenges of managing critically injured patients even with established clinical protocols and nursing guidelines. Reassuringly, all complications were quickly identified and subsequently managed. The implementation of the 28 PI filters, addressing issues such as medication delays, unplanned returns to the OR, and ICU readmissions, demonstrates WRNMMC’s continued commitment to quality improvement and to refining existing protocols.

Hospital-level changes

The complications and PI filters observed in the HKIA cohort highlight the ongoing need for continuous monitoring and iterative internal-hospital system adjustments. Further efforts are needed to optimize outcomes and ensure protocols (eg, VTE prophylaxis, sepsis guidelines) are consistently followed. In particular, there were gaps in the treatment of pediatric trauma, especially regarding DVT prophylaxis and opiate withdrawal. These highlight a need for improved protocols within the pediatric subset of trauma patients. As a result, WRNMMC collaborated with local civilian and military pediatric surgeons to develop additional guidelines and recommendations, which have since been incorporated into internal WRNMMC pediatric trauma protocols. Another critical adaptation occurred to enhance cultural competency. This included a cultural overview by the Inner-City Muslim Action Network to guide medical personnel on Islamic medical ethics.

Additionally, inperson interpreters were contracted to replace telephone-based services, ensuring more effective communication. Nutritional accommodations were also made, and specific dietary items were added to the menu to meet cultural and religious requirements. Furthermore, trauma care training for nursing was enhanced after this experience. WRNMMC now mandates completion of the Society of Trauma Nurses trauma training modules for all nursing staff, consistent with standard civilian trauma center operations, ensuring preparedness for future combat casualty and trauma patient care.

System-level changes

From a systemic perspective, challenges in patient identification prompted the need for a standardized naming convention across the military medical system, from Role I care to the Veterans’ Affairs Polytrauma Rehabilitation Centers. One of the most critical barriers encountered was the absence of a standardized naming convention for patients whose identities were initially unknown, particularly for Afghan nationals. Afghan patients arrived with inconsistent and often non-interoperable identifiers, including variations in names, medical record numbers, trauma registry entries, and evacuation tracking data. These discrepancies created delays across multiple domains of care and logistics.

Specifically, inconsistent identifiers significantly impeded patient movement through the patient evacuation coordination cell, sometimes delaying transfer to WRNMMC. They also complicated the Department of State and Homeland Security’s screening and clearance procedures, contributing to bottlenecks in entry authorization. Within the clinical domain, variable identifiers disrupted radiology and laboratory information systems, creating challenges in accessing current diagnostic results and archiving longitudinal imaging records. These mismatches further affected transfusion services, where patient identification is critical for safe and timely blood product administration.

In response to these issues, the MHS has implemented a standardized universal naming convention through the MHS GENESIS electronic health record. This system mandates that all MTFs follow a consistent naming protocol for unidentified or foreign national patients. The protocol assigns unique, system-wide identifiers that ensure interoperability across all echelons of care. These processes are consistent with standard civilian trauma center operations for unidentified or undocumented patients. Civilian trauma systems routinely employ established protocols for temporary patient identification, interagency coordination, and disposition planning when patients arrive without verified identity or legal status. The procedures implemented at WRNMMC during this event, therefore, did not fundamentally differ from civilian practice but rather reflected the application of established trauma system principles within a MTF context. This improvement, however, is foundational in enhancing operational medical readiness, enabling seamless data exchange, reducing administrative delays, and supporting longitudinal patient care during future mass casualty events or multinational humanitarian operations.

An additional system-level vulnerability is the limited routine trauma exposure at most MTFs. Though some physicians can participate in Military-Civilian Partnerships to maintain or sharpen skills, the majority of the multidisciplinary trauma team, including nurses and other allied health professionals, do not.^{28 29} Without routine trauma volume, system proficiency can atrophy, highlighting the importance of consideration for institutional trauma integration with military civilian partnerships, and not just at the individual level. Doing so would ensure continued preparation for future Abbey Gate-like events or large-scale combat operations (LSCO).³⁰

Limitations

The study has multiple limitations. First, the retrospective design relies on the accuracy and completeness of existing trauma registry entries and EMR documentation. As a result, the findings are subject to potential documentation bias, including incomplete capture of injuries and complications. This analysis represents the experience of a single tertiary care MTF, which may limit the generalizability of the findings to other military or civilian trauma centers. Additionally, case selection bias is inherent, as the study included only casualties transferred from LRMC who required definitive surgical intervention or critical care. This approach excludes less severely injured patients and those managed definitively at other echelons of care, potentially over-representing injury severity, resource utilization, and complication rates. Additionally, transitions in the EMR system led to incomplete capture of follow-up data, underscoring a key limitation of retrospective study design. This constraint was amplified during operational surge periods, as a substantial proportion of patients were referred from outside geographic areas and frequently received subsequent care at external institutions, limiting longitudinal outcome assessment. Despite these limitations, this study provides valuable insights into trauma system performance, multidisciplinary coordination, and opportunities for PI during a large-scale, high-acuity operational event.

Conclusion

With the reduction in active combat operations and the retirement of the previous generation of military providers, physicians, and surgeons, there is a growing risk that the military medical community may lose its operational readiness and institutional memory of hard-won lessons.³¹ Conflicts in Ukraine and across the Mediterranean region have further underscored a global shift toward LSCO, which carries profound implications for both military and civilian trauma care.32,34 The US military and the MHS must be prepared to respond not only to conventional battlefield casualties but also to the complex humanitarian and refugee crises that often accompany such conflicts.³⁵

The trauma care delivered at WRNMMC following the Afghanistan withdrawal serves as a critical case study in readiness, multidisciplinary coordination, and adaptive systems-based care. Despite a decade-long decline in combat casualty volumes, WRNMMC demonstrated the ability to rapidly scale operations and deliver high-quality, comprehensive care to both U.S. service members and Afghan evacuees. Importantly, this experience also underscores the value of a mature trauma registry infrastructure, performance improvement processes, and continuous QA mechanisms. The ability to capture detailed clinical data, analyze system performance in real time, and translate lessons learned into actionable improvements represents a foundational component of military medical readiness. It highlights the essential role of robust data ecosystems in sustaining trauma system capability.

Ultimately, as the Flagship of the MHS, WRNMMC’s experience underscores the need for sustained investment in trauma training, exposure to case complexity, infrastructure modernization, and interagency/military-civilian coordination.³⁶ The lessons learned from HKIA must drive ongoing efforts to preserve clinical expertise, refine trauma systems, and ensure the MHS remains prepared to meet the demands of future LSCO and mass casualty scenarios.

Data availability statement

Data are available upon reasonable request.