The brain stem consists of the midbrain, the pons and the medulla. Shaped like a stalk, the brain stem sits at the base of the skull where it joins the top of the spinal cord. The University Hospital of Newark, NJ, states that although small in comparison to the other areas of the brain, the brain stem controls the vital body functions of heart rate, blood pressure, breathing, swallowing, digestion, eye movement, speech and body movement.
Anatomy
Six arteries supply the brain stem with nutrients. Some of these branch off to the right side of the body and others go to the left. Providing oxygen and nourishment to the brain stem, as well as many organs, these arteries serve as a lifeline to all their connections.
Breathing Signs
A stroke occurs when one or more of the supportive arteries becomes blocked or ruptures. According to The Ohio State University Medical Center, damage or injury to the brain stem results in respiratory failure that requires artificial aid from a breathing machine. The patient, unable to control waking or sleeping, lapses into a coma.
Movement Signs
According to Strokenet, muscle movement, controlled by the brain stem, becomes impaired. Lack of balance and absence of muscle control causes falls and the patient appears clumsy. His body may shake involuntarily. Generally, these deficits affect the opposite side of the body from where the stroke occurred in the brain.
Physical Sensation Signs
The Ohio State University Medical Center, states that a strange phenomenon occurs involving the senses. The patient may perceive that when touched on his affected leg with an object, the touch came from a person’s hand. Temperature and pain sensations diminish and he does not have a sense of how his leg moves.
Other Signs
The muscles of the mouth and throat cease to work so the patient loses the ability to speak or eat. Choking becomes a serious risk. The patient may feel dizzy and may exhibit nystagmus, a flicking of the eyes from side to side. Nausea and vomiting often accompany the dizziness.
Prognosis
As reported in "Science Daily" in 2008, although fatalities in stroke victims have decreased in the last 10 years, stroke still holds its place as having a very high mortality rate. An extensive study by Thorsten Steiner, MD et al. in Heidelberg, Germany found that most brain stem stroke victims do not live beyond the first two to three days. Further, they found that the most damaged victims--those subjects already on a breathing machine when they arrived at the hospital--had the highest mortality rate. Out of those who survived, 59.5 percent had only slight or no long-term disability. They concluded that intensive neurologic care, as soon as possible, will help reduce the death rate in the future.
References
- The University Hospital, Newark, NJ: Anatomy of the Brain
- The Ohio State Medical Center: Brainstem Stroke
- Stroke Network, Abingdon Maryland: Brainstem Stroke
- American Heart Association Journals: Mechanical ventilation in brainstem stroke
- "Science Daily": Heart and Stroke Death Rate Steadily Declines; Jan. 4, 2008
