Value of lung ultrasound score for evaluation of blast lung injury in goats

Abstract

PurposeTo establish a severe blast lung injury model of goats and investigate the feasibility of lung ultrasonic score in the evaluation of blast lung injury. MethodsTwenty female healthy goats were randomly divided into three groups by different driving pressures: 4.0 MPa group (n = 4), 4.5 MPa group (n = 12) and 5.0 MPa group (n = 4). The severe blast lung injury model of goats was established using a BST-I bio-shock tube. Vital signs (respiration, heart rate and blood pressure), lung ultrasound score (LUS), PO2/FiO2 and extravascular lung water (EVLW) were measured before injury (0 h) and at 0.5 h, 3 h, 6 h, 9 h, 12 h after injury. Computed tomography scan was performed before injury (0 h) and at 12 h after injury for dynamic monitoring of blast lung injury and measurement of lung volume. The correlation of LUS with PaO2/FiO2, EVLW, and lung injury ratio (lesion volume/total lung volume*100%) was analyzed. All animals were sacrificed at 12 h after injury for gross observation of lung injury and histopathological examination. Statistical analysis was performed by the SPSS 22.0 software. The measurement data were expressed as mean ± standard deviation. The means of two samples were compared using independent-sample t-test. Pearson correlation analysis was conducted. Results(1) At 12 h after injury, the mortality of goats was 0, 41.67% and 100% in the 4.0 Mpa, 4.5 MPa and 5.0 MPa groups, respectively; the area of pulmonary hemorrhage was 20.00% ± 13.14% in the 4.0 Mpa group and 42.14% ± 15.33% in the 4.5 MPa group. A severe lung shock injury model was established under the driving pressure of 4.5 MPa. (2) The respiratory rate, heart rate, LUS and EVLW were significantly increased, while PaO2/FiO2 was significantly reduced immediately after injury, and then they gradually recovered and became stabilized at 3 h after injury. (3) LUS was positively correlated with EVLW (3 h: r = 0.597, 6 h: r = 0.698, 9 h: r = 0.729; p < 0.05) and lung injury ratio (12 h: r = 0.884, p < 0.05), negatively correlated with PaO2/FiO2 (3 h: r = −0.871, 6 h: r = −0.637, 9 h: r = −0.658; p < 0.05). ConclusionWe established a severe blast lung injury model of goats using the BST-I bio-shock tube under the driving pressure of 4.5 MPa and confirmed that ultrasound can be used for quick evaluation and dynamic monitoring of blast lung injury.