Being 'aware' of comatose state!

Bengaluru: Each of us has watched movies about the experience of a patient in a coma following severe trauma. Whether it is during the coma period or the recovery phase, these experiences have always been portrayed as exciting and thrilling in movies, despite the fact that the truth is quite the opposite.

When we return to reality after watching a movie like The Dead Zone or Insidious, a moment of epiphany occurs since we realise how tough it is for the patients and their loved ones to deal with such conditions. Although it may appear that they are unconscious and lying down on a hospital bed to an observer, a lot is going on in the patient's mind even when he/she is unable to respond. Experts and coma survivors describe what it's like to be in this condition.

Coma is a state of complete unresponsiveness to arousal says Dr Shivanand Pai, Consultant Neurologist, KMC Hospital. "It is a Greek word for 'Deep sleep' or 'Trance like state'. How long a person can stay in a coma depends on the cause of the coma. Common causes of Coma include trauma, vascular or blood vessel-related problems including strokes or brain attacks and cardiac arrest, infections of the brain and brain covering, any problem of body metabolism like low glucose, sodium and calcium, any blood oxygen-related problems like hypoxemia (low blood oxygen) or hypercarbia (high blood carbondioxide), tumours, any drug overdose or alcohol and so on," he said.

Duration of a coma depends on such causes. "Depending on what the cause is; a coma can last less than a day or months to years. Sometimes, this can also be permanent," added Dr.Shivanand.

A patient in a coma is unaware of the existence of his or her body and his surroundings. "They are unaware of who or where they are, do not possess a sleep-wake cycle, and do not respond to any call, touch or pain. In deeper stages of coma, they cannot maintain their body's vital functions like breathing, maintaining blood pressure and so on for which they need assistance. Depending on the stage of a coma, the brain waves can be studied however, in a deep coma, the brain activity is minimal," he explained.

"The three stages of coma include lethargy or drowsy stage which is a sleep like state, lies between alertness and stupor. The second stage is baseline unresponsiveness which needs application of the repeated vigorous stimulus to achieve alertness and the final stage is when there's no response to stimuli," he added.

Patients in comas typically have a poor prognosis; many do not fully recover. "Two most common causes of coma include brain trauma and cardiac arrest. Among them trauma patients do better, some studies in such patients showed 39 per cent recovery rate at 6 months. A large case study of patients done at New York hospital in 1960 of all non-traumatic coma show that only 10 per cent showed Good recovery at 1 month," he stated.

While some movies depict an out-of-body experience during the coma stage and obtaining psychic abilities after recovery, others showcase series of lucid dreams. Although one may not pick up on any sort of psychic abilities once they get out of a coma, some parts including lucid dreaming is true.

Since the patients are fluctuating between the state of sleep and wakefulness, they would experience a series of lucid dreams says Dr.KrithishreeSomanna, Consultant Psychiatrist at KMC Hospital.

"Lucid dreams are a type of dream where the person is aware that they are dreaming while they are dreaming. But in the lucid dreams of coma patients lack control of these dreams, they are semi-conscious and not entirely aware that they are dreaming. Moreover, based on the level of brain damage and the resultant physical handicap the patient also lacks the visual or auditory essence of the experiences. The basis of this lucid dreaming is believed to be due to REM (Rapid Eye Movement) sleep intrusions during a normal wakeful state of mind," she elaborated.

In in addition to experiencing lucid dreams, patients may sometimes feel a temperature change or even remember their past lives. "Dreams might also get vivid and life-like experiences. Based on the external changes in the environment like changes in temperature or hearing of known voices or sounds, the body might try to reciprocate these senses. They might also relive their past life experiences. In some cases, patients do experience visual or auditory hallucinations in the wakeful states," she added.

"In my clinical practice, I encounter coma recovering patients regularly. One of my patients reported having been with an imaginary person who assisted him in his coma phase. Some patients during those wakeful states exhibit disorientation to time and place and behave as if they are engaged in the work which they were previously doing. Depending on the level of brain injury, expressive speech deficit, confusion or amnesia some have developed new-onset mental health issues like anxiety and depression," she revealed.

Onecoma survivor opened up about his experiences and said that he went through a series of dreams whereas the other said that he could everything going on around him.

"Most of the dreams seemed normal and were connected to one-another where there was no concept of time. Although I knew that I was asleep for a long time, I could not wake up. It was as if my hands were restrained," said a survivor.

"I could hear bits and pieces of what was going on around me, I remembered everything till today and it still feels strange and it gives me the chills every time I recall the incident," added another.