Acute Respiratory Failure (ARF): – This disorder occurs when the lungs no longer meet the body’s metabolic
needs. It isn’t easily defined because it has many causes and variable
clinical presentation.
Cause: Acute respiratory failure may develop in patients
with Chronic obstruction pulmonary disease (COPD ) from any condition that
increases the work of breathing and decreases the respiratory drive.
Conditions includes: respiratory tract infection, bronchospasm, or
accumulating secretions secondary t cough suppression. Other
causes of ARF in COPD include:
Central nervous system (CNS) depression – head trauma or injudicious
use of sedatives, narcotics, tranquilizers, or oxygen
Cardiovascular disorders – myocardial infarction (MI), congestive
heart failure (CHF), or pulmonary emboli
Airway irritants – smoke or fumes
Endocrine and metabolic disorders – myxedema or metabolic alkalosis
Thoracic abnormalities – chest trauma, pneumothorax, or thoracic
or abdominal surgery.
Symptoms:
In COPD patients with ARF: hypoxemia (deficient oxygenation of
the blood) and acidemia affect all body organs.
Altered respirations. Rate may be increased, decreased, or normal;
respirations may be shallow, deep, or alternate between the two. Cyanosis
may or may not be present. Auscultation of the chest may reveal crackles,
rhonchi, wheezes, or diminished breath sounds.
Altered mentation. The patient show evidence of restlessness,
confusion, loss of concentration, irritability, tremulousness, diminished
tendon reflexes, and papilledema.
Cardiac dysrhythmias. Tachycardia (rapid heart rate), with increased
cardiac output and mildly elevated blood pressure secondary to adrenal
release of catecholamine, occurs early in response to low PaO2 (oxygen
level). With myocardial hypoxia, dysrhythmias may develop. Pulmonary hypertension also occurs.
Treatment:
Antibiotic for infection
Bronchodilators
Steroids
In COPD patients, ARF is an emergency that requires cautious
oxygen therapy
In significant respiratory acidosis persists, mechanical ventilation
through an endotracheal or a tracheostomy tube may be necessary
High – frequency ventilation may be used if the patient doesn’t respond
to conventional mechanical ventilation