Pulmonary Disorders II
Exacerbation treatment outcomes
Providers and practice will vary in defining when treatment is complete for pulmonary
exacerbation. The STOP study identified the most common markers of success for providers
including improvement in FEV1 and patient-reported symptoms (J Cyst Fibros 2017;16:600-6).
Though intravenous antibiotic therapy is known to improve lung function during an exacerbation,
eradication of organisms in culture is neither required nor expected (Expert Opin Drug Metab
Toxicol 2021;17:53-68).
Airway clearance techniques are a cornerstone of management of lung disease in CF.
The type of therapy will be tailored to a patientβs specific needs and preferences and the use of
these interventions will likely increase during treatment of a pulmonary exacerbation (Respir Care
2009;54:522-37).
High frequency chest wall oscillation, which involves an inflatable vest attached to a machine, is
the most commonly used airway clearance technique (after infancy).
Positive expiratory pressure/oscillating positive expiratory pressure involves breathing through a
mask or mouthpiece to provide back pressure to the airways during expiration as gas also builds
up behind the mucus by collateral ventilation (Cochrane Database Syst Rev 2019;11:CD003147).
| d. | Despite a low level of evidence, physical exercise is recommended as a possible airway clearance |
|---|
therapy and is frequently used as either primary or secondary clearance for patients who are
teenagers or older.
Chest. 2019;155(1):202-214) [re-number current options 2-5 to 3-6]
It is recommended that patients with CF undergo genotyping. If patients carry a select mutation,
they are eligible for CFTR modulators. CFTR modulators are oral drugs that bind to the CFTR
protein and improve its function. CFTR modulators fall within 1 of 2 classes. βPotentiatorsβ
increase the probability of the CFTR protein expressed at the cell membrane, and βcorrectorsβ
improve the intracellular processing of the CFTR protein.
Four oral agents are FDA approved within the CFTR modulator class. All agents require dose
adjustments for severe hepatic impairment or if coadministered with CYP3A4 inhibitors. With all
agents, liver toxicity, elevated CK, hypertension, and cataracts should be monitored for.
Elexacaftor-tezacaftor-ivacaftor: Elexacaftor 200 mg orally daily, tezacaftor 100 mg orally
daily, and ivacaftor 150 mg orally every 12 hours
ii.
Ivacaftor 150 mg orally every 12 hours
iii.
Lumacaftor-ivacaftor: Lumacaftor 400 mg orally daily and ivacaftor 200 mg orally every 12
hours
iv.
Tezacaftor-ivacaftor: Tezacaftor 100 mg orally daily and ivacaftor 150 mg orally every 12 hours
Abrupt withdrawal of highly active CFTR modulators should be avoided to prevent a withdrawal
syndrome that has been observed (Chest. 2019;155(1):202-214).
| d. | CFTR modulators require some dietary fat for optimal absorption, and tablets cannot be crushed |
|---|
for enteral administration. Ivacaftor is available as an oral granule packet that may be dissolved
in liquid; however, there is no endorsement of administration through feeding tubes (Chest.
2019;155(1):202-214).
Nutrition
Providing adequate nutrition according to patient-specific factors during acute exacerbations is key
to maintaining metabolic function and promoting optimal outcomes.
Administer pancreatic enzymes to treat exocrine dysfunction.