Inflammatory Activity in Atelectatic and Normally Aerated Regions During Early Acute Lung Injury.
Acad Radiol
; 27(12): 1679-1690, 2020 12.
Article
en En
| MEDLINE
| ID: mdl-32173290
ABSTRACT
RATIONALE AND OBJECTIVES:
Pulmonary atelectasis presumably promotes and facilitates lung injury. However, data are limited on its direct and remote relation to inflammation. We aimed to assess regional 2-deoxy-2-[18F]-fluoro-D-glucose (18F-FDG) kinetics representative of inflammation in atelectatic and normally aerated regions in models of early lung injury. MATERIALS ANDMETHODS:
We studied supine sheep in four groups Permissive Atelectasis (nâ¯=â¯6)-16 hours protective tidal volume (VT) and zero positive end-expiratory pressure; Mild (nâ¯=â¯5) and Moderate Endotoxemia (nâ¯=â¯6)- 20-24 hours protective ventilation and intravenous lipopolysaccharide (Mildâ¯=â¯2.5 and Moderateâ¯=â¯10.0 ng/kg/min), and Surfactant Depletion (nâ¯=â¯6)-saline lung lavage and 4 hours high VT. Measurements performed immediately after anesthesia induction served as controls (nâ¯=â¯8). Atelectasis was defined as regions of gas fraction <0.1 in transmission or computed tomography scans. 18F-FDG kinetics measured with positron emission tomography were analyzed with a three-compartment model.RESULTS:
18F-FDG net uptake rate in atelectatic tissue was larger during Moderate Endotoxemia (0.0092 ± 0.0019/min) than controls (0.0051 ± 0.0014/min, p = 0.01). 18F-FDG phosphorylation rate in atelectatic tissue was larger in both endotoxemia groups (0.0287 ± 0.0075/min) than controls (0.0198 ± 0.0039/min, p = 0.05) while the 18F-FDG volume of distribution was not significantly different among groups. Additionally, normally aerated regions showed larger 18F-FDG uptake during Permissive Atelectasis (0.0031 ± 0.0005/min, p < 0.01), Mild (0.0028 ± 0.0006/min, p = 0.04), and Moderate Endotoxemia (0.0039 ± 0.0005/min, p < 0.01) than controls (0.0020 ± 0.0003/min).CONCLUSION:
Atelectatic regions present increased metabolic activation during moderate endotoxemia mostly due to increased 18F-FDG phosphorylation, indicative of increased cellular metabolic activation. Increased 18F-FDG uptake in normally aerated regions during permissive atelectasis suggests an injurious remote effect of atelectasis even with protective tidal volumes.Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Respiración Artificial
/
Lesión Pulmonar Aguda
Límite:
Animals
Idioma:
En
Revista:
Acad Radiol
Asunto de la revista:
RADIOLOGIA
Año:
2020
Tipo del documento:
Article