As healthcare professionals, we’ve all been there: frantically searching through guidelines and recommendations for questions that need a quick answer. Recently, I’ve struggled to come up with evidence-backed recommendations for COPD exacerbations, specifically when to use antibiotics and what antibiotics to use. It appeared to me the GOLD guidelines were more outpatient-focused, so it was difficult to confirm what I thought I remembered from school with real evidence. This isn’t the end-all be-all guide to end all guides on the topic, but a brief summary of my findings could help guide you in the right direction for your next COPD patient.
1. WHEN DO I USE ANTIBIOTICS?
There are two scenarios to start antibiotics, and a trump card to ignore those scenarios. What do I mean by this? Here’s the explanation:
Antibiotics should be started/continued in patients that meet either of the following criteria
a. Increased dyspnea, increased sputum purulence, AND increased sputum production
Or
b. Patients on ventilator support (including NIPPV)
The trump card? Patients with a procalcitonin less than 0.1ng/mL are UNLIKELY to benefit from antibiotic usage for COPD exacerbations.
2. WHAT ANTIBIOTICS DO I USE?
Evidence is highly conflicting. For me, I like the approach of stratifying the exacerbation as mild/moderate/severe and selecting antibiotics from there.
Mild exacerbation (FEV1>50% predicted, <3 exacerbations a year)
-First Line: Doxycycline 100mg PO BID or Cefuroxime 500mg PO BID
-Second Line: Azithromycin 500mg PO daily
Moderate Exacerbation (FEV1 36-50% predicted, 3 or more exacerbations per year, 65 years or older)
-First Line: Augmentin 875/125mg PO BID or Doxycycline 100mg PO BID
-Second Line: Azithromycin 500mg PO Daily
Severe Exacerbation (FEV1<35% predicted, life-threatening respiratory failure or requires ventilator support)
-No Pseudomonas aeruginosa risk factors: Ceftriaxone 1-2g IV Q24H > Levofloxacin 750mg IV Q24H
-Positive for Pseudomonas aeruginosa risk factors (bronchiectasis, IV antibiotics in past 90 days, prior Pseudomonas sputum culture, prior intubation, chronically on steroids): Cefepime 2g IV Q12H > Zosyn 4.5g IV Q8H >> Ciprofloxacin, aztreonam, carbapenems
As a pharmacist, I like to think in terms of what organisms I need to cover. In one study, 88% of COPD exacerbations are caused by infection, of which 34% were viral. Of the bacterial causes, a large portion are attributed to 4 pathogens: Moraxella catarrhalis (gram-negative diplococcus), Streptococcus pneumoniae (gram-positive anaerobe), Haemophilus influenza (gram-negative anaerobe), and Pseudomonas aeruginosa (gram-negative bacillus).
Unless we need to cover for Pseudomonas (more common in severe exacerbations), cover for the other three: M. catarrhalis, S. pneumoniae, and H. influenza. Antibiotics that cover all 3 of these pathogens? The ones recommend above! Doxycycline, cefuroxime, augmentin, and azithromycin (among others but if you’re running out of options from that list… it’s going to be an interesting time).
Antibiotic duration should be no longer than 5-7 days, unless they develop pneumonia or some other complication from the COPD exacerbation.
Of course we will also be using glucocorticoids and inhaled SABA/SAMA products while we manage COPD exacerbations with antibiotics, but I hope this provided a more succinct way to remember when to use antibiotics and which antibiotics are appropriate.