Pulmonary Disorders II
5. Definitions of ECOPD respiratory failure (GOLD 2024)
No respiratory failure
| • | RR ≤ 24 breaths/min |
|---|---|
| • | HR < 95 beats/min |
| • | No accessory respiratory muscle use |
| • | No change in mental status |
| • | Hypoxemia improved with supplemental oxygen by Venturi mask 24%–35% Fio2 |
| • | No increase in Paco2 |
Acute respiratory failure –
non–life threatening
| • | RR > 24 breaths/min |
|---|---|
| • | Accessory respiratory muscle use |
| • | No change in mental status |
| • | Hypoxemia improved with supplemental oxygen by Venturi mask > 35% Fio2 |
| • | Hypercarbia; Paco2 increased compared with baseline or elevated 50–60 mm Hg |
Acute respiratory failure –
life threatening
| • | RR > 24 breaths/min |
|---|---|
| • | Accessory respiratory muscle use |
| • | Acute changes in mental status |
| • | Hypoxemia not improved with supplemental oxygen by Venturi mask > 40% Fio2 |
| • | Hypercarbia; Paco2 increased compared with baseline or elevated > 60 mm Hg or |
the presence of acidosis (pH ≤ 7.25)
ECOPD = exacerbations of chronic obstructive pulmonary disease; Fio2 = fraction of inspired oxygen; HR = heart rate; RR = respiratory rate.
Respiratory tract infection (40%–50% of ECOPD)
Bacterial (J Infect 2013;67:516-23)
Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis are the most
common organisms.
ii.
Pseudomonas aeruginosa and other gram-negative organisms are more common in patients
with frequent exacerbations (Chest 1998;113:1542-8; Chest 1999;116:40-6; Respir Med
2003;97:770-7; Chest 2007;131:44-52; Eur Respir J 2009;34:1072-8; J Infect 2013;67:516-23).
Viral SARS-CoV-2, influenza, rhinovirus, parainfluenza, respiratory syncytial virus
Temperature change
Air pollution
Oxygen therapy is important in managing ECOPD.
achieve an Sao2 of 88-92% (BMJ 2010;341:c5462).
Initiative for Chronic Obstructive Lung Disease 2024):
A slight level of hypoxemia may serve as a trigger for their respiratory drive secondary to chronic
hypercapnia.
May increase ventilation/perfusion mismatch and decrease respiratory rate centrally and perpetuate
the Haldane effect
A recent post hoc analysis of two prospective COPD trials suggests that exceeding an Sao2 of 92%
is associated with increased mortality (HR 1.98 for Sao2 93%–96%, HR 2.97 for Sao2 97%–100%)