You Are Not Running Out of Resilience

The part of resilience that nobody photographs.

It is Saturday on-call. By lunchtime, you have seen twelve admissions. The pace is steady, the pressure is familiar, and you handle it with the practiced ease of a consultant who has seen it all before. You move through the wards, making decisions, steadying the team, and managing the quiet chaos that defines a weekend in a busy hospital.

By the time you finally climb into bed at half past two in the morning, you have made dozens of decisions. Three of those decisions were not small. They were the kind of calls that change lives, the kind that require you to weigh complex variables in seconds. You have worked a twenty-hour day on a handful of snatched calories and a great deal of adrenaline.

You get four hours of sleep.

On Monday morning, you are in clinic. The first patient sitting in front of you is a woman with a complex history and a list of questions she has waited six months to ask. She deserves a fresh mind. She deserves a clinician who can hear the thing she is not quite saying.

She does not get one. Instead, she gets the residue of your weekend.

You are calm. You are fluent. You are entirely competent. To the patient, to your colleagues, and even to yourself, you look like a model of resilience. You are still standing. You are still working. But something is missing. There is a thinning of the air.

This is the part of resilience that nobody photographs.

The Margin for Thought

We are often told that we need more resilience. The word is thrown around as a solution to every systemic failure and every personal struggle. If you are tired, you need to be more resilient. If the system is breaking, the people within it must be more resilient.

I believe this is a fundamental misunderstanding of the problem.

Most healthcare leaders are not short of resilience. They are some of the most resilient people on the planet. They have survived decades of high-stakes environments, navigated constant change, and held onto their humanity in the face of immense suffering. They are not running out of the will to continue.

They are running out of Cognitive Oxygen® (COx).

Cognitive Oxygen® (COx) is the margin a leader needs to pause. It is the mental space required to notice what is happening, to question assumptions, to hold complexity, and to choose the next right move rather than simply reacting to the loudest noise.

When we talk about oxygen in a clinical sense, we understand that it is finite. We know that without it, cells begin to struggle and eventually die. We do not ask a patient with low oxygen levels to simply be more resilient. We recognise that they are in a state of physiological crisis.

The mind works in much the same way. Attention is not infinite. Judgement has a metabolic cost. Compassion has a bandwidth. Every decision you make, every conflict you navigate, and every hour of sleep you lose thins that margin.

The Silence of Cognitive Hypoxia

When physical oxygen levels drop, the body has ways of sounding the alarm. In the world of leadership, the signs of a thinning margin are much more subtle. I call this state cognitive hypoxia.

The danger of cognitive hypoxia is that it does not cause people to fail loudly. Instead, they deteriorate quietly. Because you are a high-performing professional, you have spent years learning how to mask fatigue and stress. You know how to sound certain even when you are unsure. You know how to maintain the appearance of authority while your internal capacity is depleted.

This deterioration shows up across four linked domains:

Cognitive clarity. Your ability to process information slows. You find it harder to separate the signal from the noise. You start to rely more on shortcuts and heuristics, which are useful until they lead you into an unforced error.

Emotional steadiness. Your fuse becomes shorter. You might find yourself becoming more defensive or less empathetic. The emotional labour of leadership, which usually feels manageable, starts to feel like an impossible weight.

Behavioural discipline. You stop doing the things you know are right. You skip the team debrief. You avoid the difficult conversation. You stop questioning the status quo because you simply do not have the energy to deal with the answer.

Physical recovery. Your body stops bouncing back. The four hours of sleep no longer feel like enough to get you through the day. The fatigue becomes a baseline rather than a temporary state.

Because you stay calm enough and fluent enough, nobody sees this deterioration. The system continues to demand more, and because you are resilient, you continue to give it. But the quality of your thinking and the depth of your leadership are being slowly starved of the margin they need to thrive.

The Three Layers of Capacity

Restoring Cognitive Oxygen® (COx) is not as simple as taking a holiday or attending a wellness seminar. It requires a fundamental shift in how we view our capacity and our responsibility to the teams we lead. We have to look at the three layers where this margin is created or destroyed.

First, there is the inner layer. This is your own capacity to notice and regulate your internal state. It is the ability to recognise when your margin is thinning and to have the tools to pause and reset. It is about understanding that your brain is a biological organ with physical limits.

Second, there is the social layer. This is the team’s ability to speak, listen, repair, and trust. A team that lacks psychological safety is a team that consumes vast amounts of cognitive oxygen just to navigate internal politics and fear. A healthy social layer acts as a shared lung, allowing the team to think more clearly together than any individual could alone.

Third, there is the structural layer. This is the design of the system itself. It includes the governance, the meeting schedules, the time for recovery, and the windows of quiet that are built into the work. If the structure is designed to consume every second of your time, no amount of personal resilience will save you from cognitive hypoxia.

Why This Matters Now

I am starting this Substack because I believe the current pace of healthcare leadership is unsustainable. We are losing too many good people not because they aren’t strong enough, but because they are being asked to lead in an environment that is cognitively suffocating.

My goal is to explore how we can reclaim that margin. We will look at how clinicians actually think and decide, and how we can use tools like Red Team Thinking® to challenge our assumptions and reduce unforced errors. We will talk about the human cost of the relentless pace and how we can build systems that respect our carrying capacity.

This is a space for leaders navigating the reality of clinical work, not a home for generic corporate advice. It is a space for leaders who want to lead with calm authority and compassion, even when the stakes are high and the certainty is low.

Oxygen First

I have spent almost 25 years in high-stakes clinical leadership across seven countries. I have been the consultant on that Saturday on-call and have felt the air thinning in my own leadership. As a cardiologist and executive coach, I founded the School of Cognitive Oxygen® to help leaders create the cognitive margin needed to think clearly, decide wisely, and remain deeply human under pressure. Together with my co-author, Claire.Ayres, we explore what it takes to protect that margin—not only for leaders, but for the teams and systems they serve.

I invite you to subscribe and join this conversation. We will look at the tools of metacognition, the practices of emotional intelligence, and the structural changes that can restore the oxygen to our systems.

We cannot change the pressure of the work, but we can change how we respond to it. We can choose to stop relying solely on resilience and start protecting our capacity to think.

Dr Toomas Särev FRCP

Consultant Cardiologist & Executive Coach

Creator of the Cognitive Oxygen® (COx) framework