What complications might be encountered?
The range of complications which may be encountered are very broad.
Each patient's course with ARDS will by an individualized process susceptible to
many different influences and effects from many different factors. The following are
some on the complications which may be encountered.
Barotrauma is one complication that may occur with ARDS. The
word means injury caused by pressure. Volutrauma is injury caused by the volume of
air used to inflate the lungs. In ARDS, the lung is weakened and, combined with the
high pressures of the ventilator and volume of air used to inflate the lungs, there is a
risk of lung rupture called a pneumothorax. If this occurs, it leads to an
accumulation of air in the pleural cavity. The pleura form a smooth, moist lining
around the lungs. Normally, there is no air in the small space between the pleura
and the lungs. When a pneumothorax develops, a chest tube is inserted by a physician
through the patient's chest wall, into the pleural cavity outside the partially collapsed
lung to remove the air. The tube is connected to a suction machine to help the lung
inflate. The suction machine or wall suction is used until the patient's lung is
healed enough to stay inflated on its own. A pneumothorax may also be related to
trauma or to other procedures used in treating the patient.
Bacterial infections are a common complication of ARDS and
contribute to continued lung injury. The lung is the most common site of infection.
Lung infection or pneumonia may be difficult to diagnose in a patient with ARDS
because, as we've said, the patient's chest X-ray is already very abnormal. The
nurse or respiratory therapist will obtain a specimen of phlegm or sputum from the lungs
by suctioning through the patient's endotracheal tube when the patient has a fever.
The specimen is sent to the laboratory for a culture, a method that allows any bacteria
that are present to grow. In this way, bacteria that may be causing an infection can
be identified and the sensitivity of the bacteria to antibiotics can be determined.
Sometimes the doctor may want to obtain a sputum specimen from deeper in the lung.
In that case a bronchoscopy may be performed by a physician. The bronchoscope is a
flexible tube like instrument that contains a light and an eyepiece. It is inserted
through the patient's endotracheal tube and the doctor can see inside the patient's
airways. A special small brush is passed through the bronchoscope and into an area
of the lung that appears infected. This brush is then sent to the laboratory for
culture and sensitivity tests. Sedative medications are used to keep the patient
comfortable and the ventilator is adjusted during this procedure so the patient's
breathing continues without a problem.
Bacterial infections may also occur in other parts of the body such
as the bloodstream, the urinary tract, sinuses, skin or muscle, the abdomen or the spinal
All of these areas are tested for infection in various ways.
Antibiotics are used when an infection is present or suspected. Antibiotics are
powerful drugs and must be used carefully. Bacteria may become resistant, especially
if the antibiotics are used when they are not needed. When a patient has been
treated with many antibiotics for a long period of time they are at risk of developing a
fungal or yeast infection, which may cause further problems.
Abnormal organ function in addition to the lung failure caused by
ARDS can develop and may involve the liver, kidney, brain, blood or immune system. These
organ dysfunctions may be related to the underlying illness, to treatment or may occur
through the same inflammatory process which injured the lungs. If kidney failure
occurs, the patient may be maintained with dialysis, which is treatment that removes waste
products from the patient's blood by circulating the blood through a special machine.
Liver failure is a difficult problem to treat because there is no
replacement for the many functions that the liver performs in our bodies. Ongoing
infections, despite appropriate antibiotic therapy, may be due to dysfunction of the
immune system. Patients may become unconscious or confused when they previously have
been alert and oriented due to dysfunction of the brain or central nervous system.
Blood transfusions or replacement of certain elements of the blood, such as platelets,
which are needed for clotting of the blood, may be required.