Status Asthmaticus

Definition
  • Status asthmaticus is severe and persistent asthma that does not respond to conventional therapy; attacks can occur with little or no warning and can progress rapidly to asphyxiation.
  • Infection, anxiety, nebulizer abuse, dehydration, increased adrenergic blockage, and nonspecific irritants may contribute to these episodes.
  • An acute episode may be precipitated by hypersensitivity to aspirin.
  • Two predominant pathologic problems occur: a decrease in bronchial diameter and a ventilation–perfusion abnormality.

status asthmaticus

Pathophysiology

Asthma per se is the constriction of the bronchial smooth muscles, swelling of the bronchial mucosa linings and thickened sputum. With these happening, it narrows the bronchial tree, and is apparent to bronchial asthma. This results to hypoxemia, respiratory alkalosis (there will be decreasing PaO2 and respiratory alkalosis, a decreased PaCO2 and an increased pH) and respiratory acidosis (PaCO2 increase as the status asthmaticus worsens) thereafter.

Manifestations
  • Wheezing
  • Labored breathing
  • Prolonged exhalation
  • Neck engorgement

Assessment and Diagnostic Findings
  • Primarily pulmonary function studies and ABG analysis
  • Respiratory alkalosis most common finding

N
URSING ALERT: Rising PaCO2 to normal or higher is a danger sign, signaling respiratory failure.

Medical Management
  • Initial treatment: beta-2-adrenergic agonists, corticosteroids, supplemental oxygen and IV fluids to hydrate patient. Sedatives are contraindicated.
  • Highflow supplemental oxygen is best delivered using a partial or complete nonrebreather mask (PaO2 at a minimum of 92 mm Hg or O2 saturation greater than 95%).
  • Magnesium sulfate, a calcium antagonist, may be administered to induce smooth muscle relaxation.
  • Hospitalization if no response to repeated treatments or if blood gas levels deteriorate or pulmonary function scores are low.
  • Mechanical ventilation if patient is tiring or in respiratory failure or if condition does not respond to treatment.

Nursing Management

The main focus of nursing management is to actively assess the airway and the patient’s response to treatment. The nurse should be prepared for the next intervention if the patient does not respond to treatment.

  • Constantly monitor the patient for the first 12 to 24 hours, or until status asthmaticus is under control. Blood pressure and cardiac rhythm should be monitored continuously during the acute phase and until the patient stabilizes and responds to therapy.
  • Assess the patient’s skin turgor for signs of dehydration; fluid intake is essential to combat dehydration, to loosen secretions, and to facilitate expectoration.
  • Administer IV fluids as prescribed, up to 3 to 4 L/day, unless contraindicated.
  • Encourage the patient to conserve energy.
  • Ensure patient’s room is quiet and free of respiratory irritants (eg, flowers, tobacco smoke, perfumes, or odors of cleaning agents); nonallergenic pillows should be used.