Guide to the Comatose Patient

Expert advice for families and caregivers

Eelco Wijdicks

• Publisher: Mayo Clinic Press
• Year: 2022
• eBook ISBN: 9781945564192
• Topic: Medicine
• Subtopic: Caregiving

Caring for a loved one in a coma is a distressing time, full of many questions, and often, not as many answers. Guide to a Comatose Patient is a first-of-its-kind book that steps into the shoes of the neurologist, to show the perspective of the staff caring for their loved ones — what worries us, how we think and intervene, what we can and cannot predict, and what we know as a certainty. In our hospital ICUs, there are more than a dozen comatose patients at any given point of time. Causes of coma can range from drug-induced coma—in which medications are used to calm the patient and allow the ventilator to work properly—to coma due to intoxication and coma related to a brain injury. No matter the reason, it can be a distressing time for loved ones. Guide to a Comatose Patient is a helpful guide for any family member or loved one confronted with coma. Author Eelco F. M. Wijdicks, M.D., Ph.D., a leading neurologist and attending neurointensivist at Mayo Clinic, begins each chapter by sharing helpful anecdotes from a career spanning four decades, before diving into the answers to commonly asked questions, such as: · What are the causes of coma? · When will the patient wake up and recover? · When is no recovery expected? · When should we consider organ donation? · What are the rates of survival? While there are many books on families’ experiences with acute traumatic brain injury and coma, Dr. Wijdicks offers an unusually candid conversation that allows a peek inside the minds of the doctors caring for your loved one. Having had many experiences talking to families having to make difficult decisions at a very difficult time, Dr. Wijdicks’s message is hopeful while remaining grounded in reality—a reality in which facts must dictate actions. Guide to a Comatose Patient provides important information so that families better understand treatment options, but most importantly, the book offers an open dialogue and optimal transparency to help provide hope and healing through times of grief.

Chapter 1:
What is coma?

A conversation

Physician: I’m sorry to tell you that your son has been in a terrible accident. His brain was injured, and he’s been comatose since he arrived here.

Family: We didn’t expect this, and we’re so unprepared. It’s so hard seeing him like this. Can he hear us? I thought he was squeezing my hand, but then he stiffened up. It looks like he’s crying. And why is he clenching his teeth?

Physician: Your son likely isn’t aware of his surroundings and what he’s doing and showing us. Right now, that’s a good thing. He can’t feel pain from his bone fractures, and he doesn’t know he’s on a ventilator.

Family: What now?

Physician: First, let me explain what it means to be comatose — for him and you.

The question “What is coma?” isn’t simple to answer. Unconsciousness, or coma, is a weighty subject but, so is consciousness. Human consciousness — the basis of thought and reasoning — is enduringly mysterious. So is the opposite: being unconscious or comatose, commonly referred to as being “in a coma.”

Visiting someone in the hospital who’s comatose can be very emotional, and family and friends often have many questions. They want to know what their loved ones are experiencing. Do their loved ones feel helpless or “locked into” their bodies? Can they sense others around them? Can they hear and understand what’s being said? What will they feel, see and hear as the coma lifts? This book is my attempt to help you understand what it means to be in a coma.

The ancient Greeks used the word κῶμα (coma) for the state of deep sleep, but it doesn’t describe what people who are comatose experience. The general public may talk about people being in a coma, unresponsive or “out of it” as if they mean the same things, but that’s not the case. The way a comatose patient looks isn’t an indication of whether he or she is responsive. The key is the patient’s level of consciousness, a complex concept that I’ll explain in this chapter.

Consciousness vs. unconsciousness

Before I talk about unconsciousness, it’s important to understand consciousness. Being conscious (or, in essence, thinking) is uniquely human. It’s what makes us aware of who we are and what we do, and it allows us to reason. Each of us has an inner life and our own experiences on which we reflect. As human beings, we have free will. Our actions are willful when we’re conscious.

No one knows where consciousness comes from. There’s no specific, physical area in the brain where it resides. Consciousness is relative, too. Little is necessary for us to become less conscious of our surroundings. (If it just started raining outside, you may not have noticed because you’re reading this book.)

Despite its considerable importance, human consciousness is truly one of the greatest mysteries of neuroscience and a field of renewed study, particularly by philosophers and basic neuroscientists. Over the centuries, many theories about consciousness have been discussed and discarded. We’re nowhere close to having an explanation about the biologic and physical basis of the condition.

The mechanics of consciousness

The brain consists of cells and tracts. Neurons are the major working cells in the brain, and they connect with one another through multiple branches (dendrites) that extend out of them. Neurons can be grouped in a so-called nucleus. Nerve tracts are bundles of nerve fibers connecting nuclei. What we do know is that we need a certain number of connections in our brains to process, memorize, motivate and make plans.

In order to function, the networks between these connections need more than a dozen chemical substances, called neurotransmitters. Neurotransmitters are the brain’s messengers. These messengers can fire up or tamp down signals coming from neurons. The discovery of neurotransmitters led to an understanding of why certain drugs affect our wakefulness and mood. But we haven’t even scratched the surface in exploring the nature of consciousness — one of the ultimate questions of life.

Disease or injury doesn’t usually make us lose our consciousness for good; it just lessens consciousness to some degree. When we recover, we regain thought driven by emotion (and sometimes reason). Even the most serious brain injuries don’t cause people to lose their identities. For a time, however, individuals may not know where they are and may seem detached from everybody and everything.

Loss of identity after a brain injury is often the stuff of fantasy, such as what happens in Robert Ludlum’s “Jason Bourne” novels or Wim Wenders’ film “Paris, Texas.” What the author and film director are describing is a rare condition called psychological amnesia. People diagnosed with it behave as if they don’t know who they are. Zombie films often have a similar theme.

Neurologically, people are defined as being conscious if they’re aware and awake. Awareness involves perception and self-monitoring. Awakeness is the opposite of sleep. Sometimes, the eyes are open and able to see, but a person isn’t necessarily fully alert. For physicians, unconsciousness (coma) means that the structures in the brain that keep a person awake aren’t functioning, and the person loses awareness.

The role of the brainstem

It took many years of experimental research before scientists understood which structures in the brain control awareness, how they work, and where they’re located. The breakthrough came in the 1950s with the discovery that a small series of networks in the brainstem, called the ascending reticular activating system (ARAS), determines coma or wakefulness.

It seems incredible that the brainstem — a small structure underneath the brain — determines whether we open our eyes in the morning and are ready for the day, but it’s true. The brainstem also directs the urge to breathe, contains cells that keep our blood pressure in check and is crucial to motor movement.

When part of the brainstem is damaged, we lose a good deal of function. But the heart, gastrointestinal system and kidneys still work because they’re self-sufficient and don’t require any higher-order input from the brain. If the brainstem completely ceases to function, however, all the body’s essential functions are lost. I come back to this in Chapter 7.

Assessing whether a patient has impaired consciousness or is in a coma is purely a clinical judgment based on certain assessments described later in this chapter. I will explain key structures in the brain in more detail here, clarify the numerous synonyms for coma and describe the neurologic examination of patients who are comatose.

Coma vs. other levels of consciousness

Degrees of coma are difficult to categorize. As a result, less precise terms often are used to describe different levels of consciousness, and there’s also confusion in the medical literature. Being aware of the many terms used to define unconsciousness and what those terms mean is important so that we all have the same understanding when they’re used.

Awakeness and normal consciousness vs. abnormal states

For years, I’ve been keeping a list of words I’ve heard people use to describe diminished consciousness. They include:

• Altered mental status
• Clouded
• Kind of out of it
• Noncommunicative
• Out of it
• Semicomatose
• Somnolent
• Sopor
• Stupor
• Unarousable
• Unresponsive

Physicians are reasonably good at recognizing the extremes of the spectrum of consciousness, which span from alertness to deep, unresponsive coma. We’ve also been trained to recognize conditions that mimic coma, such as locked-in syndrome and some psychiatric states. It’s the conditions in between that pose real challenges. The spectrum of neurologic conditions is wide. Patients can present with states of consciousness ranging from being quickly responsive to stimuli, to opening their eyes only after being prodded, to remaining immobile with their eyes closed no matter what’s going on around them or how much they’re stimulated.

Establishing simple categories for states of awareness is often best for effective communication between family members and members of the patient’s health care team. The first thing that a physician will determine when asked to see a patient who’s inattentive is whether the person is awake. A range of possible diagnoses then flows from there.

The figure displays the normal and abnormal states of consciousness physicians encounter in patients who are hospitalized. When we see a patient who’s staring quietly and inattentive, the person’s condition may be hard to identify. These individuals are encephalopathic (translated as “brain disease”), which basically tells us very little. Some of them may be in delirium (delirious). Delirium includes several disturbed elements, including language, perception, orientation, mood and sleep. Traditionally, delirious patients are loud, agitated, accusatory, paranoid and offensive. Some of my medical colleagues say they’ve seen patients who are very quiet while hallucinating and delirious, but I’m not so sure about that. The delirium I typically see is restlessness with sweating, rapid heart rate and wide pupils. There’s a tendency to just call this acute brain failure, but vague terms have little medical value.

An individual’s level of consciousness usually falls into one of five categories: alert, delirious, drowsy, stuporous or comatose:

• Alert patients are observant and may say hello. They are fully attentive, complete tasks promptly when asked, actively ask questions and are engaged and “with it.”
• Delirious patients, as just described, are in a deeply disturbed state characterized by restlessness and incoherence.
• Patients who are drowsy can be awakened and will stay awake when engaged in conversation. They have a reduced attention span and may drift off during a conversation. Their memory is markedly impaired.
• The term stupor describes a condition in which the eyes remain closed if the person is lightly prodded but open in response to something painful. The individual will also tend to make movements as if to push away what’s causing the pain. When the stimulation is absent, the patient immediately becomes unresponsive once again.
• The simplest definition for comatose is an unreceptive and unresponsive state. Unlike patients who are sleeping, those who are comatose don’t wake up, speak, or open their eyes when someone talks loudly or pinches them. In response to stimuli, their arms and legs may react by withdrawing or as a reflex. If comatose patients move at all, the action isn’t done with a purpose.

Lack of content also is an important hallmark of coma. Content refers to an awareness of what’s happening in one’s surroundings. An example would be knowing that a family member is at the bedside, recognizing the family member or being able to communicate in a rational, logical way.

People who’ve regained consciousness after being comatose often don’t recall what happened while they were unconscious. For many individuals experiencing varying degrees of unconsciousness, it’s like a veil descends on them, making them oblivious to their immediate surroundings (and, in the end, that might be a good thing). In coma, the door closes fully.

Explaining locked-in syndrome

Patients experiencing locked-in syndrome, which is very uncommon, may appear to be comatose, but they’re not. Their eyes are open and the eyes blink and move vertically, but they make no other movements. These individuals are more or less awake but unable to show it. It’s as if there’s a major barrier they cannot overcome and they’re boxed in.

Locked-in patients can feel, hear and see, but their sight is blurred by double vision because their eyes don’t line up. Locked-in syndrome can occur in patients with a new brainstem abnormality (often a stroke) that involves the front of the pons. The pons is the site of several nerve bundles that create most eye movements, facial movements such as grimacing and head movements. Patients who are locked in can move their eyes vertically because the syndrome doesn’t affect the upper part of the pons, called the mesencephalon, which produces vertical eye ...

Table of contents

• Acknowledgments and dedication
• Preface
• Chapter 1: What is coma?
• Chapter 2: What causes coma?
• Chapter 3: How is coma treated?
• Chapter 4: When can we expect awakening and recovery?
• 89Chapter 5: When is recovery not likely to happen?
• 105Chapter 6: What is palliation, or comfort care?
• 121Chapter 7: When is organ donation considered?
• 137Chapter 8: What are our moral obligations and duties?
• 153Chapter 9: How should health care providers and families interact?
• 167Chapter 10: What about experimental and unproven therapies?
• Frequently asked questions
• Suggested readings