System Resilience In Mass Casualty Incidents: Sustained Adaptability

Dr. Richard Cook was an anesthesiologist as well as a pioneering researcher and thought leader in resilience engineering. He elegantly used bones as the archetype of resilience and resilience engineering—living systems that are neither rigid nor fragile, but constantly adapting to the demands placed upon them. Bones endure stress by remodeling themselves, reinforcing areas of strain, and drawing resources to mend fractures, all without losing their fundamental integrity. In Cook’s view, resilient systems must behave similarly: absorbing pressure, learning from disruption, and evolving in ways that make future performance stronger rather than weaker. True resilience, he argued, is not about resisting change, but about dynamically reshaping oneself in response to it—quietly, continuously, and intelligently, just as bones do beneath the surface of everyday life.

In a chapter Richard wrote for the book Resilience Engineering: Concepts & Precepts, he recounts an opportunistic observation of a healthcare system responding to a bomb blast. He happened to be visiting a country where the threat of terrorist attacks is woven into the fabric of daily life. Through repetition and necessity, the country's health systems had evolved into a living model of sustained adaptability.

I had the chance to witness a simulated mass casualty incident and how the first responders dealt with the situation, courtesy of Yuval Bitan. He has done much human factors work towards designing for emergencies.

Mass casualty incident (MCI) triaging is coordinated nationally in this country, not by nearest-hospital proximity but dynamically at the scene. Paramedic commanders classify injuries on-site, dispatching the critically wounded to major trauma centers while diverting less severe cases to smaller hospitals. The intent is not merely to save lives but to prevent any single hospital from being overwhelmed, preserving the flow of normal operations even in the midst of extraordinary events.

This strategy creates a new kind of burden: reuniting families with their missing loved ones scattered across the city's hospitals. At every hospital, social workers gathered the fragments—descriptions of missing persons, scraps of memory about clothing, height, the last phone call made. Simultaneously, hospitals logged their incoming patients, noting what little could be known: gender, age, a torn jacket, the shoes still clinging to soot-streaked feet. These two streams of information were stitched together through a shared, real-time network spanning across hospitals. Clarity was not an incidental outcome but an intentional creation.

Families arriving at any hospital were received at waiting rooms already provisioned with beverages and quietly staffed with social workers ready to meet each wave of grief and uncertainty. Outside, hospital spokespersons managed the crush of media presence, forming a kind of protective callus, absorbing external pressures without letting them fracture the clinical core. This mirrors how bones preemptively strengthen at points of expected strain.

Inside, operating rooms and trauma bays flexed dynamically. The most severely injured bypassed the trauma rooms altogether and were taken directly to surgery, preserving critical spaces for others. Routine documentation was deferred except for those records, like blood type cross-matching where precision could not be compromised. As in bone healing, the system prioritized essential functions first, trusting that secondary repairs could come later.

Perhaps the biggest feature of success is how a seasoned resilient system not only adapts to crisis but returns to baseline without exhausting itself. Although several operating rooms remained occupied with trauma surgeries, the rest of the operating suites quietly resumed their scheduled cases. After all, operating rooms are expensive resources and are typically planned with near-full utilization. The return to normalcy was neither declared nor celebrated, it simply happened, like the slow, invisible remodeling of bone after a fracture has been set. Resilient performance is accommodating the extraordinary with minimal effects to the routine, and returning without being undone.

The aftermath of disruption should be more than a return to the status quo. It should be an opportunity to build new margin and readiness. We see glimpses of this after COVID-19: National Healthcare Group polyclinics feature physically segregated clinics and pharmacies in designated "orange zones" for patients with fever and respiratory illnesses, a structural enhancement that would boost their pandemic response capabilities.

When bones encounter atypical stress, they draw first from within, tapping whatever reserves they can muster to stabilize and reorganize. Thereafter, they invest strategically in the very places where the strain was felt most keenly, increasing their density—and with it, their inherent capacity to adapt and tolerate again. With each passing crisis, healthcare stakeholders must ask themselves: are their operations adequately resourced and deliberately strengthened to endure the next unforeseen strain, or are their systems osteoporotic, deprived of nourishment and load-bearing growth, one fracture away from a crippling breakdown?

Richard left us on 31 August, 2022. In one of the eulogies, Richard was described as an inquisitive researcher who never stopped pondering. His was able to draw elegant analogies from complex concepts, and I draw inspiration from him. I see his legacy in all the friends I've made in the resilience engineering community.

Prof. Richard Cook. Wikipedia

Even at our dinner Richard couldn't help but whip out his laptop to give us a presentation of his latest thoughts, even if it's about his family. Photo circa 2019.