Stress factors and their effects during coma

Stress is a common and frequently overlooked factor affecting individuals in a coma.

Under normal circumstances every system in the body is in a dynamic state of equilibrium with chemical changes constantly occurring to prevent the delicate balance from shifting too far one way or the other. In turn, all the different systems are in equilibrium with each other.

Any force that tries to upset the equilibrium, to offset the balance, is called a stress. When the stress succeeds in changing the balance, unwanted effects occur.

It would be impossible to enumerate all the stress factors and their effects on these pages, but those described will serve to illustrate the tremendous battle the body must undergo in order to recover from a severe injury to the brain.

The very first stress factor in brain injury is the immediate physical effect of the blow to the head or of the sudden lack of oxygen. The result is death of some brain cells and a shock-like response in others, the effect of which is immediate cessation of the functions controlled by those cells. The physical changes in the brain cells cause a loss of the delicate balance between cells, resulting in edema or swelling of the brain. This in turn causes increased pressure in the brain, causing further death of brain cells, causing further loss of function, causing further edema. In addition, the edema caused some chemical changes which in turn result in a toxic or poisoning effect on brain cells, thereby destroying additional cells.

As various functions are lost, stress is applied to other systems. Loss of movement or of muscle contractions decreases the resistance in the blood vessels of the limbs thereby affecting blood circulation, blood pressure and increasing the workload on the heart. Impairment of normal digestive functions may result in over secretion of stomach acids, causing ulcers of the stomach ("stress ulcers").

The multiple methods applied by medicine in an attempt to counter the stresses and correct their effects cause stress in themselves. Intravenous lines require perforation of the skin and a vein, in other words mechanical injury. Fluids injected directly into the blood stream modify the volume of fluids in the circulatory system in an artificial manner, shifting the normal balance and causing the system to have to work harder. Medications administered are usually chemicals that are not normally in the body, therefore they have to be processed, thereby putting stress on the liver and kidneys. Various tubes placed in the trachea (tracheostomy), in the bladder (Foley catheter), in the stomach (feeding tubes), represent foreign bodies that the system must adapt to, not to mention the mechanical irritation that they cause. The results are fluid loss (stress), infections (stress), bypassing physiological functions or mechanisms (stress).

The use of respirators is another source of stress because while providing the vital life sustaining source of oxygen to the lungs and blood stream, a ventilator "breathes" at a constant rate without the subtle variations that normal respirations go through to adapt constantly to the ever varying needs of the body. In addition, a certain amount of fluid loss occurs through the respirator, sometimes overlooked in the long term setting -- more stress!

Multiple stresses on the biological system result from relative or total immobility, the effects of which include decalcification of bones, decrease in the metabolic rate of the body resulting in poor adaptation to temperature changes - more stress! The building blocks of the body start breaking down. A normal balance between building (anabolism) and breaking down (catabolism) shifts to catabolism, with decreasing muscle bulk, loss of protective fatty tissues, weight loss -- stress, stress, stress, all of which in turn affect the volume of circulating blood and the demands on the heart. Progressive breakdown of body tissues leads to respiratory infections, bladder infections and breakdown sores (pressure sores) which in turn may become deep and infected -- stress, stress, stress! Immobility also leads to stiffening of the joints (ankylosis), shortening of muscle tendons (contractures) and calcification of muscles (myositis ossificans) -- stress, stress, stress!

Finally, sensory deprivation from lack of stimulation triggers disorientation and emotional stress in the patient who has some awareness, which further trigger catabolism and skin ulceration, placing further stress on the organism leading to further breakdown. The effects of sensory deprivation are overwhelming and only recently have become recognized on the same acute care settings, but are still totally ignored in the majority of long term care settings.

The management of patients in a coma requires an aggressive attack on the effects of unavoidable stress and a vigorous attempt to reduce or prevent all potentially avoidable stress. The latter requires restoring "physiological" or natural functions and "normal" environmental settings as early as possible in the management of the patient. Stress, in all its forms, remains the hidden, or not so hidden once one recognizes it, enemy of the patient in a state of prolonged coma or prolonged inactivity, and the management team must be on guard constantly, at all times, prepared to act dynamically to eliminate the destructive elements. This takes strength, perseverance, patience and courage...To those who have done it, congratulations! To those who are doing it, keep up the good work!!

Mihai D. Dimancescu, M.D.
Chairman of the Board, Coma Recovery Association, Inc.