Dialysis Disequilibrium Syndrome
Individuals who suffer from kidney disease often require treatment many times each week to maintain a healthy level of water and nutrients in the body. Although dialysis does an effective job of replacing some of the kidney function that is lost, it can also lead to neurologic signs and symptoms that can be very uncomfortable and even life-threatening. A condition known as dialysis disequilibrium syndrome is a very serious medical condition that is believed to occur as a result of swelling in the brain.
While dialysis has been around for nearly 50 years, the cause of this severe medical condition is not fully understood. Some healthcare professionals believe that the symptoms patients sometimes experience including restlessness, headache, coma, confusion, or even death are the result of a slowing of the transport of urea out of cells in the brain. As the amount of urea in the brain increases, it creates a concentration gradient that causes fluid to move out of the blood vessels and into the extravascular compartment. This accumulation of fluid creates elevated pressures within the brain and leads to the neurologic deterioration that is often characteristic of dialysis disequilibrium syndrome.
Most of the patients who suffer from this illness experience the signs and symptoms following their very first treatment. Over the years, dialysis facilities have learned that the best approach to handling the condition is to gradually introduce patients to the treatment process and to make sure urea levels are within an acceptable range. As an individual begins to acclimate to the procedure, the treatment duration is increased. An alternative approach to prevention is to perform hemofiltration in place of traditional dialysis. This strategy takes advantage of the fact that hemofiltration utilizes a convective removal of solute rather than diffuse removal. This approach results in a lower level of fluctuation in particle concentration and can prevent the concentration gradient that is responsible for increased intracranial pressure seen in dialysis disequilibrium syndrome patients.
In the event that a patient shows signs of this illness, a dialysis technician should recognize that something is wrong and have a basic appreciation of the treatment process so that they can work effectively with nurses and physicians. The primary objective in a situation where someone is experiencing dialysis disequilibrium syndrome is to reduce the pressure inside the brain. The administration of mannitol and hypertonic saline is one approach that is used to create a concentration gradient inside the blood vessels so that fluid passes out of the brain and into the intravascular compartment. Unfortunately, many attempts at reversing the intracranial pressure are not successful and patients die. For this reason, it is critical that dialysis personnel do everything they can to prevent dialysis disequilibrium syndrome from developing in the first place.
In general, dialysis patients should not be overly concerned about the potential for developing this condition. Over the years, the number of patients who develop the kind of severe symptoms outlined above has decreased due to increased awareness of the need for preventive measures. Some risk factors that patients and personnel should look for include…
- First-time patients
- Urea exceeding 175 mg/dL or 60 mmol/L
- Metabolic acidosis
- Very young or elderly patients
- Prior history of neurologic disease
- Chronic kidney disease