Impact and Challenges of Future Large-Scale Combat on Traditional Battlefield Medical Care

The U.S. military is preparing for future large-scale combat operations, and medical personnel are already aware that the "golden hour" principle may not be achievable in such scenarios. In future conflicts with near-peer adversaries, ground and air medical evacuation platforms may be threatened, preventing casualties from reaching second-echelon surgical care within an hour of injury. Consequently, the casualty rate in future large-scale conflicts is expected to rise significantly. Preliminary estimates from U.S. military exercises suggest that casualty rates could reach up to 55% in future conflicts, overwhelming the current structure and capacity of military medical support.

Large-scale operations will introduce new ethical dilemmas in battlefield medical care. The future medical logistics requirements may far exceed actual support capabilities. The inability to achieve air superiority will hinder the rapid evacuation of casualties, and the high number of combat casualties may alter the basic principles of utilizing limited medical resources on the battlefield. Future warfare may fundamentally shift from previous U.S. engagements characterized by unlimited resources over time in asymmetric conflicts to high-intensity conflicts with limited capabilities. Creative solutions will be necessary to ensure timely logistics support.

Future medical evacuation may shift to more accessible platforms and could be supplemented with autonomous tools. Additionally, there may be discussions and applications of the concept of "reverse triage," where the focus would be on treating those who may not have the most severe injuries but can return to the front lines the quickest.

When hundreds of casualties are in distress, the treatment facilities moving along primary supply routes with front-line troops (such as battalion aid stations, treatment companies, or fleet hospitals) may struggle to operate, further complicating casualty care. Many NATO Level III medical facilities (self-sufficient medical units) lack mobility. For example, according to 2023 U.S. Army data, a hospital center with 240 beds requires 46 C-17 aircraft to deploy into a combat zone. Establishing an early entry 32-bed hospital on the ground needs 13 C-17s. For ground transport, the entire hospital requires a 50-car train or over 100 commercial trucks. A U.S. Air Force theater hospital with 58 beds needs 104 pallets and six C-17s to enter the combat zone, competing for transport resources with rocket and food supplies. When Level I treatment facilities must deploy with the troops on the front line, further complications arise.

The lack of air superiority increases reliance on ground evacuation platforms, including traditional vehicles and unmanned systems, which will also face challenges. Primary supply routes may become congested due to the return of casualties and the forward movement of supplies, ultimately impacting the effectiveness of unmanned platforms (such as the Squad Multi-Equipment Transport for casualty evacuation, as seen in the image from the USAMRDC website). Meanwhile, logistics supply lines and casualty evacuation platforms are likely to become prime targets for a near-peer adversary. The GAO (U.S. Government Accountability Office) reported on medical supply shortages during the 1991 Gulf War, affecting decision-making for casualty care in 10 surveyed military medical facilities. Shortages included oxygen, morphine, antibiotics, plasma, lab reagents, and vaccines. Medical supplies are expensive, have short shelf lives, and may quickly become ineffective without proper storage. Additionally, regions affected by military conflict may experience shortages in basic medical supplies, requiring stable and continuous supply to maintain public morale.

Future military conflicts may challenge the ethical boundaries of casualty care. Large-scale operations producing massive casualties and logistical supply difficulties will force medical personnel to make life-and-death decisions. During the 2003 Iraq War, personnel at the 86th Combat Support Hospital faced tough choices due to limited supplies and only 32 beds, which were quickly overwhelmed by American and Iraqi (both civilian and enemy) casualties. Leadership had to decide which casualties received the limited tetanus vaccines. Ultimately, Iraqi casualties were prioritized for tetanus shots as the U.S. evacuation chain ensured American casualties would receive necessary vaccines upon reaching the next care echelon, whereas Iraqis lacked such guarantees.

Additionally, quickly returning soldiers to the battlefield is crucial for winning the next fight. From January 2007 to mid-March 2020, 37% of over 10,000 casualties recorded in the U.S. Joint Trauma Registry returned to duty within 72 hours. Triage, a critical aspect of battlefield care, helps determine which casualties to treat first in mass casualty situations to save the most lives. Triage is based on ethical principles to maximize benefits for the majority. According to the Army Emergency War Surgery manual, "immediates" are those who can be saved with rapid treatment and typically comprise 10% of casualties, including those with blast injuries or trunk gunshot wounds requiring immediate surgical intervention. These surgeries may consume significant medical supplies and hours of limited surgical time. The next category, "delayed," refers to casualties whose condition may deteriorate into "immediate" without timely treatment within 24 to 48 hours and typically make up 30% of casualties. "Minimals," accounting for 50% of casualties, need minimal treatment and may return to duty. Traditionally, "expectants," those unlikely to survive, comprise less than 10%, receiving only palliative care.

Currently, the U.S. military is discreetly discussing "reverse triage." In the face of hundreds of casualties from a hypersonic missile strike, should "immediates" be deprioritized so medical personnel can save a higher proportion of "delayed" casualties before supplies run out? "Delayed" casualties, often referred to as the walking wounded, may quickly return to the front line with appropriate care. The first rule of tactical combat casualty care is to return fire, take cover, and establish fire superiority. This principle may need consideration at operational and strategic levels. These are the pressing issues the military medical community is grappling with.

The first step in addressing these challenges is establishing clear expectations of future casualty rates among leaders from squad to company level. Commanders who experienced high survival rates in Iraq and Afghanistan are now battalion and brigade leaders. The "Talisman Sabre 23" joint multi-national exercise anticipated 8,500 casualties over 18 days or 1,000 over three days, with a 30% casualty rate.

The medical evacuation section of the U.S. Joint Health Service Support Doctrine (ATP 4-02.2) outlines "urgent/urgent surgical," "priority," and "routine" evacuation categories, corresponding to the common triage terms "immediate," "delayed," and "minimal." Lessons from the Talisman Sabre 23 exercise emphasize the need to focus on saving the 30% "delayed" casualties rather than the resource-intensive 10% "immediates." Theoretically, this approach could save three times as many casualties. "Urgent" is defined as requiring evacuation within one hour to save life, limb, or eyesight. On a large-scale battlefield with prolonged evacuation times and scarce medical resources, most "urgent" casualties will die before reaching surgical care. The concept of "reverse triage" should be researched, popularized, and incorporated into training for use in special situations.

At the tactical execution level, training for front-line medical personnel needs to change, emphasizing whom they should prioritize for care. Given the threats in future tactical areas and the inability to quickly evacuate casualties to surgical facilities, prolonged field care (PFC) should transition from a concept to necessary practice. With limited medical supplies, should each soldier carry one liter of IV fluid and related materials to hydrate during PFC? Similar to past practices of designating soldiers to carry NBC (nuclear, biological, chemical) prophylaxis drugs.

Walking blood banks and the Ranger low-titer O-type blood program were solutions developed for blood needs during low-intensity operations and counterterrorism actions. These operations involved support personnel donating blood. In contrast, large-scale operations will require new solutions as donors will not have days to recover, and any support site may be at risk. Walking blood banks are useful, especially in forward bases during irregular warfare but may not be practical in future high-intensity conflicts requiring nearly all personnel to engage in combat.

Supply and timely replenishment of medical supplies are also critical issues for policymakers to consider now. Modern aircraft have much longer ranges than WWII aircraft. If fighting a near-peer adversary in the Pacific with common A2/AD (anti-access/area denial), is airdropping medical supplies a viable option? Can medical supplies be delivered by drones, and can casualties be evacuated using drone platforms? In large-scale operations, how will medical supplies reach the tactical front lines? Lastly, to treat more casualties, should more medical personnel be recruited for military action alongside activating the National Disaster Medical System?

Large-scale operations will require a significant paradigm shift from past conflicts. Commanders should anticipate higher casualty rates and prepare accordingly. However, the medical maxim of doing the greatest good with limited supplies to ensure others may live remains unchanged.