High-flow nasal cannula oxygen therapy versus non-invasive positive pressure ventilation in treating patients with acute exacerbation of chronic obstructive pulmonary disease type Ⅱ respiratory failure complicated with respiratory muscle fatigue

  Objective  To compare efficacy of high-flow nasal cannula oxygen therapy (HFNC) and non-invasive positive pressure ventilation (NPPV) in treatment of patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) type Ⅱ respiratory failure complicated with respiratory muscle fatigue.

  Methods  A total of 90 hospitalized patients with AECOPD type Ⅱ respiratory failure were divided into group A (46 cases, mild respiratory muscle fatigue) and group B (44 cases, severe respiratory muscle fatigue) according to auxiliary respiratory muscle utilization score. Group A was randomly divided into group A1 (n=24, HFNC treatment) and group A2 (n=22, NPPV treatment), and group B was divided into group B1 (n=19, HFNC treatment) and group B2 (n=25, NPPV treatment) according to random number table method. Arterial partial pressure of oxygen p_a(O₂), arterial partial pressure of oxygen carbon dioxidep_a(CO₂), auxiliary respiratory muscle mobilization score, diaphragm excursion during quite breathing (DEq) and diaphragm excursion during deep breathing (DEd) were compared before and after treatment in four groups; intubation rate and group change rate were compared among the four groups.

  Results  After 24 and 48 hours of treatment, p_a(O₂) in four groups was significantly higher than treatment before, and p_a(CO₂) was significantly lower than treatment before (P < 0.05); p_a(O₂)in the group B2 was significantly higher than that in the group B1, and p_a(CO₂) was significantly lower than that in the group B1 (P < 0.05). After 24 and 48 hours of treatment, the score of assisted respiratory muscle utilization in the group B2 was significantly lower than that before treatment, and was significantly lower in the group B2 than that in the group B1 (P < 0.05). After 48 hours of treatment, DEq in four groups was significantly higher than before treatment, and was significantly lower than before treatment (P < 0.05). DEq in the group B2 was significantly higher, and was significantly lower than that in the group B1 (P < 0.05). The intubation rate in the group B1 was significantly higher than that in the group B2 (P < 0.05). There was no significant difference in the change rate among the four groups (P>0.05).

  Conclusion  HFNC and NPPV have similar efficacy in the treatment of patients with AECOPD type Ⅱ respiratory failure complicated with mild respiratory muscle fatigue. The efficacy of NPPV is superior to HFNC in treating patients with severe respiratory muscle fatigue.