The severity of MODS is determined by the amount of dysfunction in six main organ systems. These systems include:
- Respiratory system
- Cardiovascular system
- Renal system
- Hepatic system
- Hematologic system
- Neurologic system
There are several different scoring systems used to determine the severity of MODS.1 To create a severity score, each organ system is evaluated and used to predict a person’s likelihood of recovery vs. death. Healthcare providers monitor an organ system through a person’s symptoms and laboratory testing.
People with MODS can develop difficulty breathing due to lung damage. Often people need to be placed on a ventilator to help them breathe.
However, although mechanical ventilation helps treat lung problems, it can sometimes cause lung injury, worsening the overall disease process. As lung dysfunction continues, the lungs fill up with fluid and start to develop scar tissue.
The worst type of lung injury found in people with MODS is acute respiratory distress syndrome (ARDS).1 Once ARDS sets in, people have difficulty maintaining oxygen in the blood and have a higher risk of dying.
The widespread inflammation associated with MODS dilates the blood vessels, slowing blood flow to tissues. This process becomes evident when a person has low blood pressure with a severe illness or injury. The vessels also become leaky, allowing fluid to collect in the tissues and skin, known as edema.
Slowed blood flow leads to clotting in some body areas, worsening the function of already damaged organs. These cumulative effects are particularly concerning when the organ affected by the decreased blood flow is the heart.
In this scenario, the heart will not function appropriately to continue to push blood to the rest of the organ systems and body. This can be considered a “silent heart attack,” which compounds the overall problem and leads to the failure of other organ systems.
Higher Risk of Death With Cardiac Dysfunction
Unfortunately, people with MODS who develop cardiac dysfunction often have a higher likelihood of dying.
The renal system includes the kidneys, which help excrete toxins and fluids from the body.
Decreased blood flow can lead to kidney dysfunction. In addition, people may need dialysis to get rid of toxins and extra fluid.
The primary sign of renal dysfunction is decreased urine output.
Kidney function can also be made worse by certain medications used during the treatment of MODS.
The liver’s function is to get rid of toxins. It makes specific proteins necessary for other organ systems to function correctly.
People with MODS and decreased blood flow can develop liver failure. People may look yellow from hepatic dysfunction. Liver failure can lead to further imbalance inside the body.
MODS is associated with a complex cascade of events that disrupt the balance of specific proteins and slow blood flow. This imbalance can simultaneously lead to bleeding and clotting.
Parts of the body are affected differently depending on the severity of MODS, the presence of previous illnesses, and the person’s genetics. The person can develop bruising and color changes to the skin. They might start bleeding inside the stomach.
The most severe problem of hematologic system failure is disseminated intravascular coagulation (DIC). The syndrome becomes evident when people spontaneously bleed around catheter sites (the tubes placed for a person’s resuscitation).
People with DIC have a poor prognosis. Only about half of people with DIC survive.
Widespread inflammation and problems with the hematologic system lead to decreased blood flow to the brain. This, in conjunction with blood clotting, can lead to brain damage, which may cause people with MODS to have a reduced level of consciousness or be confused.
These changes can also cause various other problems, including stroke-like symptoms.