Correlation between CT pulmonary vascular parameters and severity in patients with acute exacerbation of chronic obstructive pulmonary disease

Objective To explore the relationship between pulmonary vascular parameters in chest high-resolution CT (HRCT) and clinical severity in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Methods Collected 60 cases′ clinical data of AECOPD patients between January 2016 and January 2018 from Department of Respiratory and Critical Care Medicine, Shanxi Dayi Hospital Affiliated to Shanxi Medical University, including vital signs, arterial blood gas analysis, times of acute exacerbations in the previous year and chest HRCT image data during admission.It was divided into mild (no respiratory failure), moderate (acute respiratory failure-no life danger) and severe group (acute respiratory failure-life danger) according to its clinical and arterial blood gas analysis.It was divided into two groups of frequent acute exacerbation (≥2 times/year) and nonfrequent acute exacerbation (<2 times/year) according to that acute exacerbation times in the previous year.Measurement of chest HRCT cross-sectional area of small pulmonary vessels<5 mm2 as a percentage of total lung area (%CSA<5), and ratio of the diameter of the pulmonary artery to that of the aorta (PA/A), analysis %CSA<5 and PA/A differences of each group, and comparison of pulmonary vascular parameters in chest HRCT between different acute exacerbation frequencies groups, and analysis of %CSA<5 of AECOPD patients with PA/A and clinical indicators. Results (1)There were 20 cases in each group of mild, moderate and severe, and no significant difference in gender, age and smoking index between the three groups.(2)The difference of %CSA 0.05). Compared with nonfrequent acute exacerbation group [(0.69±0.16) %], %CSA<5 of frequent acute exacerbation group [(0.58±0.13)%] decreased significantly, the difference was statistically significant (t=2.881, P=0.006). (3)%CSA<5 of AECOPD patients was significantly positively correlated with arterial pH value and oxygen partial pressure, and significantly negatively correlated with acute exacerbation frequency, carbon dioxide partial pressure and PA/A (r=0.372, 0.328, -0.363, -0.342, -0.323, all P<0.05). Conclusions The cross sectional area of small pulmonary vessels in chest HRCT is significantly decreased in AECOPD patients of the severe group and the frequent acute exacerbation group.Suggest that %CSA<5 may be an effective indicator to assess the clinical severity of COPD and play a significant guiding role in the diagnosis and treatment during the AECOPD. Key words: Pulmonary disease, chronic obstructive; Tomography, X-Ray computed