Effects Of High-flow Nasal Cannula Oxygen Therapy On Patients With Acute Exacerbation Of Chronic Obstructive Pulmonary Disease With Respiratory Failure

Objective:High-flow nasal cannula oxygen therapy(HFNC)has become a new method for the treatment of hypoxic acute respiratory failure..Acute episodes of chronic obstructive pulmonary disease(COPD)are usually accompanied by hypoxemia and hypercapnia.Currently,the therapeutic regimens of COPD mainly include continuous low-flow oxygen(LFO)inhalation,non-invasive mechanical ventilation(NIV)and so on.This study aims to explore the effect of high-flow nasal cannula oxygen therapy on patients with acute exacerbation of chronic obstructive pulmonary disease(COPD),and evaluate the clinical outcomes of this regimen compared with low flow oxygen inhalation and noninvasive mechanical ventilation.Methods:From October 2017 to June 2018,20 patients with acute exacerbation of COPD with non-life-threatening respiratory failure(AECOPD II)were collected at the Department of Respiratory Medicine,the Fifth Hospital of Suzhou City.The patients were treated high-flow nasal cannula oxygen therapy by using Drager infinity c 300 produced by Delger,Germany,with the condition of 37℃,continuous humidification,relative humidity 100,flow rate 30-40 L/min,oxygen concentration 31L/min and taking closed breath as far as possible.At the same time,two groups as the controls were set up,one group with 20 cases treated with low flow oxygen therapy and the other group with 20 cases treated with non-invasive mechanical ventilation.In the low flow oxygen inhalation group,the volume of oxygen was continuously absorbed through the nasal catheter,and the oxygen flow rate was 2.5L/(oxygen concentration 31%).In the non-invasive mechanical ventilation group,BiPAP-30 non-invasive ventilator made by Weikang Company of America was used.Bi-level positive airway pressure ventilation with mouth and nose mask was used.The pressure was gradually increased to IPAP 12-20 cmH2O,PEEP 4-6 cm H2O and oxygen flow rate was 5 liters/min according to the improvement of patient undefined oxygenation and comfort.All three groups were treated with inhaled tracheal dilatants,intravenous or oral hormones,and antibacterial therapy.The effects of high-flow nasal cannula oxygen therapy inhalation on PaO2,PaCO2,pH,respiratory frequency and heart rate in AECOPDⅡ patients were observed and compared with low flow oxygen inhalation and noninvasive mechanical ventilation respectively.Results:The results showed that upon treatment for two hr,the PaO2,PaCO2,pH value,respiratory frequency,respiratory comfort score and respiratory distress score were significantly improved in 20 patients with high-flow nasal oxygen(P<0.05),and the heart rate appeared to decrease without a statistical difference.After 4 hours of high-flow nasal cannula oxygen therapy treatment,PaO2,PaCO2,pH,respiratory frequency,heart rate,respiratory comfort score and respiratory distress score were significantly improved compared with those before treatment(P<0.05).After 8 hours of treatment,the PaO2,PaCO2,pH,respiratory frequency,respiratory comfort score and respiratory distress score were significantly improved in the nasal high flow oxygen group compared with the low flow oxygen inhalation group.The difference was statistically significant(P<0.05),but there was no significant difference in heart rate between the two groups(P>0.05).Interestingly,after 8 hours of treatment,the improvement of respiratory comfort score in high-flow oxygen through nasal cannula group was more obvious than that in non-invasive mechanical ventilation group(NIV)(P<0.05),but the PaO2,pH value,respiratory rate,and heart rate were significantly decreased in NIV group(P<0.05).There was no significant difference in respiratory distress score(P>0.05).Conclusion:In patients with acute exacerbation of COPD with non-life-threatening respiratory failure,high-flow nasal oxygen therapy can effectively improve PaO2,PaCO2,pH value,relieve respiratory frequency,reduce heart rate,improve respiratory comfort and alleviate respiratory distress.Compared with the low flow nasal oxygen therapy,the high-flow nasal oxygen therapy was superior to the low flow oxygen in improving the PaO2,PaCO2,pH value,respiratory frequency,respiratory comfort score and respiratory distress score.Compared with non-invasive mechanical ventilation,the two groups could improve the PaO2,PaCO2,pH value,respiratory frequency,heart rate,respiratory comfort score,respiratory distress score,but the respiratory comfort score of high-flow nasal oxygen inhalation was better than that of non-invasive mechanical ventilation.As aspects of reducing PaCO2,non-invasive mechanical ventilation is better than nasal high flow oxygen inhalation.