Dynamic inhomogeneity of aeration along the vertical axis of the lung may predict weaning failure regardless of diaphragm dysfunction

• Published in: Journal of critical care Vol. 65; pp. 186 - 191
• Main Authors: Moon, Do Sik, Huh, Jin Won, Hong, Sang-Bum, Koh, Younsuck, Lim, Chae-Man
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.10.2021; Elsevier Limited
• Subjects: Adult; Anesthesia; Diaphragm (Anatomy); Diaphragm - diagnostic imaging; Diaphragmatic dysfunction; Electrical impedance tomography; Extubation; Guillain-Barre syndrome; Humans; Intensive care; Lung; Patients; Pleural effusion; Respiration, Artificial; Sepsis; Software; Spontaneous breathing trial; Ultrasonic imaging; Ultrasonography; Ventilation; Ventilator Weaning; Ventilators; Weaning; Germany; DD; TIV; GI; TSA; SBT; Weaning; ROC; IR; spRVD; Spontaneous breathing trial; RSBI; Electrical impedance tomography; EIT; Diaphragmatic dysfunction; EELI
• ISSN: 0883-9441; 1557-8615
• DOI: 10.1016/j.jcrc.2021.06.010

This study aimed to investigate dynamic changes of lung aeration during a spontaneous breathing trial (SBT) in patients with diaphragm dysfunction (DD) and to predict weaning failure using electrical impedance tomography (EIT). We enrolled 40 adult patients who received mechanical ventilation over 48 h and were eligible for SBT with a T-piece. All patients were screened for DD using ultrasonography before SBT. EIT data, including global inhomogeneity index (an off-site parameter), and temporal skew of aeration (TSA) (an on-site parameter) were collected. Sixteen (40%) patients had DD. During SBT, the tidal impedance variation decreased by 32% from baseline in patients with DD and by 14% in those without DD (p = 0.001). The global inhomogeneity index in the SBT failure group (n = 9) was 0.92 (median), and that of the SBT success group was 0.65 (p = 0.004). The TSA along the vertical axis of the lung was 12.0% and 2.0%, respectively (p = 0.001). With a vertical TSA cutoff of ≥4.35%, SBT failure was predicted with a sensitivity of 88.9% and specificity of 96.9% (area under the curve: 0.955). Dynamic inhomogeneity of aeration along the vertical axis of the lung as assessed using TSA predicts SBT failure regardless of DD. This trial was retrospectively registered at cris.nih.go.kr (identifier: KCT003567; release date February 27, 2019). •The Temporal skew of aeration, electrical impedance tomography index, could predict spontaneous breathing trial failure.