Identifying an exacerbation
Prompt and appropriate treatment for exacerbations is required but management depends on recognising the nature of the episodes.
The diagnosis of a bacterial infection is made when a combination of symptoms exist. A positive sputum culture, by itself, does not indicate an exacerbation but can be helpful in guiding future antibiotic use.
The definition of an exacerbation of bronchiectasis according to Hill et al 2017 is:
A deterioration in three or more of the following key symptoms for at least 48 hours:
sputum volume and / or consistency
breathlessness and / or exercise tolerance
fatigue and / or malaise
AND a clinician determines that a change in bronchiectasis treatment is required.
It is desirable for patients to have an action plan, including a prescription for an appropriate antibiotic, to commence when the above criteria for an exacerbation are met.
An exacerbation is classified as severe in the presence of:
acute respiratory failure
exacerbated chronic respiratory failure
a significant decline in SaO2 or respiratory function or hypercapnia
fever of more than 38°C
(Martinez-Garcia et al. Arch of Broncopneumol.2017)
An exacerbation is classified as very severe in the presence of:
altered mental status
need of intensive or intermediate care unit admission
(Martinez-Garcia et al. Arch of Broncopneumol.2017)
Management of acute exacerbations
Five key issues in managing an exacerbation (Torres 2017 World Bronchiectasis conference)
Is it an exacerbation?
Is the exacerbation severe?
Accurate microbiological assessment
What type of antibiotics should be prescribed?
Appropriate duration of treatment
During an exacerbation, there is often a proliferation of bacterial pathogens and increased airway and systemic inflammation. Treatment with antibiotics has been shown to reduce bacterial burden as well as inflammation. Deciding when a patient has an acute exacerbation is based on symptomatic and physiologic changes, rather than any specific lab investigation. An acute bacterial infection is often preceded by an increase in sputum volume and sputum purulence. There may also be additional symptoms including malaise, dyspnoea, pleuritic chest pain and/or haemoptysis. Systemic symptoms such as fevers, sweats and rigors may be present, but many patients will have an exacerbation without those symptoms. Viral infection can also trigger exacerbations.
Although there are no randomised control trials evaluating the role of antibiotics during exacerbations of bronchiectasis, oral antibiotic therapy is appropriate for most mild to moderate exacerbations with the choice of antibiotic usually based on the organisms previously identified in sputum samples. Antibiotics for exacerbations of bronchiectasis have been shown to reduce sputum volume, sputum purulence, bacterial load, CRP, markers of sputum inflammation and improve symptoms. Clinical experience suggests that higher doses and a longer duration of antibiotics are often more effective than lower doses and shorter courses of the same antibiotic in bronchiectasis. Additionally, sputum sensitivity results do not necessarily predict clinical response to antibiotic therapy.
The choice of antibiotic should be based on previous sputum isolates where possible. In patients with beta-lactamase producing organisms, empiric treatment with amoxilcillin or amoxicillin and clavulinic acid is appropriate. For patients allergic to penicillin, doxycycline is an appropriate alternative. For patients known to be colonized with Pseudomonas aeruginosa, ciprofloxacin is an appropriate agent. Patients who have had MRSA previously isolated can be treated with a combination of rifampicin and fusidic acid. If previous sputum isolates are not available, then empiric therapy targeting Haemophilius influenzae is appropriate.
Duration of therapy
The appropriate duration of therapy is not well defined, but for most exacerbations a 7 – 14 day course of antibiotics is appropriate. If Pseudomonas aeruginosa has been identified, most clinicians would recommend a 14 day course of treatment.
Indications for Hospitalisation
If a patient requires intravenous antibiotics, hospitalisation is indicated. For patients who have Pseudomonas aeruginosa resistant to ciprofloxacin, intravenous therapy is indicated. Other indications for hospitalisation include the presence of respiratory failure with a respiratory rate >/= 25/min, hypotension, fever >38C, hypoxic respiratory failure with SpO2 </= 92% or failure to improve after a course of oral antibiotics. It is important that patients admitted to hospital are also treated with appropriate airway clearance techniques.
There is little evidence to support or oppose the long-term use of oxygen therapy to reduce mortality in patients with chronic respiratory conditions other than COPD (TSANZ Oxygen Guidelines)
Supplemental oxygen therapy may be used if there is evidence of hypoxic respiratory failure (SpO2 < 90% or PaO2 < 65mmHg). While this may improve oxygenation, it will not necessarily have any impact on dyspnoea. If supplemental oxygen is used, it is appropriate to maintain a saturation of >92%.
The addition of oxygen therapy to a patient’s management plan should be determined by a comprehensive clinical assessment, not just the requirement of an increase in PaO2.
For further information on oxygen therapy see TSANZ Oxygen Guidelines