My wish is to provide useful information for those touched by the practice of critical care medicine. This starts with patients and their families. I hope to convey how challenging this area of medicine is on multiple levels and to impart how much uncertainty there is in treating these very sick patients.
Critical care illness is the care of the sickest of the sick and it is expected that most of us at some point in our lives will end up in an intensive care unit. For many of us, it is where we will spend our last days. This will also likely involve us as family and friends of those who become critically ill.
Critical care illness is a complex phenomenon. By complex I do not mean complicated-although this area of medicine certainly is. I mean complex from a systems approach. Life processes embodied by living organisms constitute a complex system with each of its parts making for additional layers and layers of complexity. Each of our multiple organ systems from the cardiovascular to immune system constitutes a separate complex system and this complexity extends to the individual cells that make up our bodies.
Living organisms exhibit a type of complexity described as dynamical and adaptable. Dynamical because life processes are always changing and adaptive because organisms can adapt to new circumstances. In fact, many of our responses to illness are adaptive. This adaption not only pertains to life processes but also importantly can relate to our evolutionary heritage. Fever is a quintessential evolutionary adaptive response to infection. Many infectious organisms fare less well at the higher body temperature that fever produces and fever also revs up the our body to help fight infection. The complexity part deals with how involved life processes are and how each of its parts, each constituting a complex system in and of itself, are all intricately connected. So, all this makes critical care illness and treating the critically ill enormously challenging and well, very complicated.
Frequently, there are not clear cut and simple paths to take in treating the critically ill. There is a high degree of uncertainty and things generally become less and less clear the sicker the patient is. Coupled with this uncertainty is tremendous variability (variation) in patients and their responses to illness and treatment. One patient who may be severely ill and who may not be expected to survive will pull through. Whereas another patient, with similar illness but not so sick, will not survive. And in these instances, it is unclear why the one patient survived and the other did not.
Much of the practice of medicine is educated and experienced guess work and this is especially true in the care of the sickest patients. We have a tremendous amount of technology; a nearly endless supply of medicines; and a dizzying array of tests and procedures. Often there is a false sense of security garnered from all that modern medicine has to offer. Again, it is not so simple to treat abnormal values from tests and just do procedures in pursuit of getting the diagnosis and in treating illness. One aspect of complex systems is that all the parts are not so simply connected that fixing the malfunctioning parts individually will mend the whole. Indeed, one important characteristic of complex systems is that changes in the parts that make up the system, whether this change is part of an illness or part of a cure, can yield unpredictable responses. Again, that uncertainty.
Nearly every treatment or procedure has down sides. All of us in this profession know all too well the disastrous complications that sometimes come from testing and treatment. Sometimes these problems are worse than the patient’s initial illness. What our sage master clinician-teachers have always told us is ever so true: good medicine starts with the patient and all this technology with its testing and procedures is just an extension of getting the patient’s story and doing a thorough examination (the history and physical). This is the art of medicine and it can seem magical when it works. It is awe inspiring for someone new in this profession to watch a seasoned clinician forgo a procedure or ignore testing seemingly at the peril of the patient, take a different tact, and the patient get better.
Critical care physicians differ from other physicians in that we learn to be comfortable with this uncertainty. Non-ICU physicians tend to over test and treat because they are unsure and this can cause an endless array of problems not only in potential complications but also in treating the results of all this testing which may not be accurate. Such behavior also confuses what really may be going on with the patient. In the end, it’s all just a good guess but guessing solidly based upon that impression wrought by the history and physical, garnered by experience, and supported by the prudent use of procedures and tests. Often the best evidence we have that we are right in this field is the patient getting better. And this is all we need. It makes all that other testing superfluous and moot. It also makes this field intensely gratifying when it’s our guesses, first and foremost, that make our patients better.