Literature List Electrical Impedance Tomography

Electrical impedance tomography (EIT) is a non-invasive, radiation-free tool to monitor regional changes in ventilation. This report describes, for the first time, that unilateral atelectasis in an extremely low birth weight infant results in a loss of regional ventilation measured by EIT in the affected lung. Conclusion: EIT is currently the most promising technique to monitor regional lung aeration continuously at the bedside in this vulnerable population. ES Bodenstein M et al. Hints for cyclical recruitment of atelectasis during ongoing mechanical ventilation in lavage and oleic acid lung injury detected by SpO2 oscillations and electrical impedance tomography Exp Lung Res. 2014 Nov; 40(9); 427-38 Purpose of the Study: Detection of cyclical recruitment of atelectasis after induction of lavage (LAV) or oleic acid injury (OAI) in mechanically ventilated pigs. Primary hypothesis is that oxygen oscillations within the respiratory cycle can be detected by SpO2 recordings (direct hint). SpO2 oscillations reflect shunt oscillations that can only be explained by cyclical recruitment of atelectasis. Secondary hypothesis is that electrical impedance tomography (EIT) depicts specific regional changes of lung aeration and of pulmonary mechanical properties (indirect hint). Materials and Methods: Three groups (each n = 7) of mechanically ventilated pigs were investigated applying above mentioned methods before and repeatedly after induction of lung injury: (1) sham treated animals (SHAM), (2) LAV, and (3) OAI. Results: Early oxygen oscillations occurred in the LAV group (mean calculated amplitude: 73.8 mmHg reflecting shunt oscillation of 11.2% in mean). In the OAI group oxygen oscillations occurred hours after induction of lung injury (mean calculated amplitude: 57.1 mmHg reflecting shunt oscillations of 8.4% in mean). The SHAM group had no relevant oxygen oscillations (<30 mmHg, shunt oscillations < 1.5%). Synchronously to oxygen oscillations, EIT depicted (1) a decrease of ventilation in dorsal areas, (2) an increase in ventral areas, (3) a decrease of especially dependent expiratory impedance, 3) an increase in late inspiratory flow especially in the dependant areas, (4) an increase in the speed of peak expiratory flow (PEF), and (5) a decrease of dorsal late expiratory flow. Conclusions: SpO2 and EIT recordings detect events that are interpreted as cyclical recruitment of atelectasis. CR Guerin C, Frerichs I Getting a better picture of the correlation between lung function and structure using electrical impedance tomography Am J Respir Crit Care Med. 2014 Nov; 190(10); 1186-7 The authors report the case of a 56-year-old woman with lymphangioleiomyomatosis, which received a single left lung transplant from a cadaveric donor on October 10, 2004. As per the authors, EIT is considered to be potentially useful for monitoring regional ventilation in mechanically ventilated patients. The main benefit of the EIT examination in the presented case was the information obtained regarding the functional status of the native and transplanted lungs. Electrical Impedance Tomography (EIT) Literature List