Increasingly my hope on this topic derives not from the idea that we humans will cease and desist our destructive proclivities, but rather that we will redirect our restless ingenuity toward active solutions. To borrow from Matt Damon in The Martian: we will prevail, if we do prevail, because we “science the s#@t out of it”!

There is genuine hope in that direction. The combination of rising seas and thirsty people is cause to get very good, very fast, at desalination at scale; I hold out hope we will. The need to build stuff, and sequester carbon, is cause to get good, and fast, at carbon capture and repurposing technologies; I hold out hope we will. The ominously welling powers of wind, wave, and sunlight menace our futures, but could be harnessed to fuel them instead; I hold out hope they will. Engineers will be the heroes if we win the war with our own calamitous momentum.

But even to this fraught hope, I feel a need to append another anxiety, born of patient care. As a physician, I cheer for the pending epiphanies of engineers, but offer this forewarning to be configured into them: options get very bad, very fast, once multi-organ-system failure sets in.

I no longer see patients, pulled now in many directions offering the promise (I hope to fulfill) of health impact at scale. But I took care of patients for nearly 30 years after medical school- and for many of those early years, was a clinician primarily.

Like most of my clinical colleagues, I had patients in the ICU at times, and spent dedicated time there during my training. As the name suggests, care in the ICU is intense. Conditions are dire, interventions are elaborate, monitoring is copious and detailed. I applaud my intensivist colleagues- doctors, nurses, respiratory therapists, physical therapists, dietitians, and others- who practice daily this elaborate choreography of life and death.

Being a patient in the ICU almost invariably means that life is at risk, and that in turn generally means that at least one vital organ system is failing. When that indeed is the case, initial interventions are directed there: support for a failing heart, dialysis for failing kidneys, ventilation for failing lungs.

But this, ineluctably, proves to be a lesson in humility the engineers who will attempt to doctor the planet must heed. Whatever we do to compensate for a failing element of the extraordinary human system, we do far less well than the native homeostasis. We support cardiac function in ways that can damage the kidneys. We substitute dialysis for healthy kidney function at the risk of both fluid overload and hypotension, as well as electrolyte imbalances.

We ventilate lungs forever at the risk of damaging delicate alveoli. We treat cancer with drugs that can damage the heart; treat the heart with drugs that can damage the liver; and can barely treat a failing liver at all. The life-saving treatments of inflammation run amok may shut down the adrenal glands, and may induce the risk of overwhelming infection. The treatment of infection invites potentially lethal bacterial overgrowth of the colon.

This brief overview is the tip of the iceberg of contingent vulnerabilities. We refer to this cascade as multi-organ-system-failure, and it is more norm than exception in the ICU. It’s as if the body is screaming at us: everything you are doing to help me is crude and brutal and damaging. Alas, that indictment is entirely true. Though it’s the best we can yet do with 21st century medicine; though it may at times be enough to save a life; though the good of it outpaces the bad when it is well practiced; though it may be skillful, and expert, and dutiful, and essential- still, it is crude and brutal and damaging.

There is nothing so elegant as the balance of healthy homeostasis in a complex organism. There is nothing so difficult as playing the surrogate to that native symphony.

And if that is true of the complex human organism, how much more so for the superorganism of Earth. We’ve had discrete indications of this along the way: the ravages of introducing non-native creatures into pristine ecosystems, the unintended harms of engineered flood control. The modern insights of waterway management largely relate to undoing the prior projects of the Army Corps of Engineers. The law of unintended consequences presides at all times.

The parallels are ever more noteworthy as we learn that a human being is an ecosystem, too. That, really, is the ultimate implication of everything you hear about the importance of the microbiome. It doesn’t just take a village to raise a vital human being; it takes a village simply to be one.

Whether or not the planet has its own, unique identity as a living entity is a matter for philosophers. The pragmatists among us should concede that it may not matter. That the planet has evolved is established fact, ecosystems adapting in tandem. That natural systems have achieved equilibria through elaborate, balanced inter-dependencies is established fact.

The loudest clamor against the climate change alarms has always been that such predictions are imperfect. That, of course is true, inviting the most obvious and robust of rebuttals: we could be wrong in either direction. That such predictions were more right than wrong is now on abundant display.

But there are many indications the predictions erred in the direction of optimism, not pessimism. This happens in the ICU as well, where a prognosis based on the management of one failing organ system fails to anticipate the contingent failure of the next, and the next, and the next.

Patients in the ICU can and do recover, although often without ever reaching the prior vitality they owned. All the king’s horses and all the king’s men may now have means to suture or glue a cracked egg shell, but still have no means to unscramble an egg.

When they do recover, it is partly applications of advanced medicine, largely the intrinsic healing capacity of the human body, seeking restoration of the native balance.

I suspect with the planet matters may be much the same, and the intensive ministrations of engineers will be warranted. Those involved should learn what every doctor already knows. We will never be as good at managing the body as it is at managing itself. Our job is to support the opportunity for healing and homeostasis, and when we see indications of those taking hold, show respect, and get out of the way.

We also know, of course, it would be far better to support those native attributes by every means at our disposal before ever the ICU is required.

-fin