CRITICAL CARE NETWORK
Mechanical Ventilation and Airways Management Section
1,2,3 Continuous monitoring of the tidal volume, plateau pressure, and positive end-expiratory pressure (PEEP) is crucial to maintain LPV. Electrical impedance tomography (EIT) is a noninvasive, radiation-free, imaging method of the electrical conductivity distribution inside the human body.4 Integrating EIT into invasive mechanical ventilation allows imaging of the regional lung ventilation as affected by the mechanical ventilation settings as well as the patient position. It can also provide a personalized approach to determining the optimum ventilatory settings based on individual patient conditions.5,6
Optimum PEEP titration is crucial to prevent lung collapse as well as overdistension. In a single-center, randomized, crossover pilot study of 12 patients, optimum PEEP titration was carried out using a high PEEP/FiO2 table vs EIT in moderate to severe ARDS. The primary endpoint was the reduction of mechanical power, which was consistently lower in the EIT group.7 EIT also allows the assessment of regional compliance of the lungs. There are reports regarding the superiority of regional compliance of lung over global compliance in achieving better gas exchange, lung compliance, and weaning of mechanical ventilation.8 EIT could assess the patient’s response to prone positioning by illustrating the change in the functional residual capacity between supine and prone positioning.9 In addition, by visualization of the ventilated areas during spontaneous breathing and reduction of pressure support, EIT could help in weaning off the mechanical ventilation.10
CHEST
Dr. Akram M. Zaaqoq
In conclusion, EIT can be a tool to provide safe and personalized mechanical ventilation in patients with respiratory failure. However, there are limited data regarding its use and application, which might become an interesting subject for future clinical research.
– Akram M. Zaaqoq, MD, MPH
Member-at-Large
References
1. Amato MB, Barbas CS, Medeiros DM, et al. Effect of a protective-ventilation strategy on mortality in the acute respiratory distress syndrome. N Engl J Med. 1998;338(6):347-354.
2. Brower RG, Matthay MA, Morris A, et al. Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. N Engl J Med. 2000;342(18):1301-1308.
3. Neto AS, Simonis FD, Barbas CSV, et al. Lung-protective ventilation with low tidal volumes and the occurrence of pulmonary complications in patients without acute respiratory distress syndrome: a systematic review and individual patient data analysis. Crit Care Med. 2015;43(10):2155-2163.
4. Adler A, Boyle A. Electrical impedance tomography: tissue properties to image measures. IEEE Trans Biomed Eng. 2017;64(11):2494-2504.
5. Jang GY, Ayoub G, Kim YE, et al. Integrated EIT system for functional lung ventilation imaging. Biomed Eng Online. 2019;18(1):83.
6. Sella N, Pettenuzzo T, Zarantonello F, et al. Electrical impedance tomography: a compass for the safe route to optimal PEEP. Respir Med. 2021;187:106555.
7. Jimenez JV, Munroe E, Weirauch AJ, et al. Electric impedance tomography-guided PEEP titration reduces mechanical power in ARDS: a randomized crossover pilot trial. Crit Care. 2023;27(1):21.
8. Costa ELV, Borges JB, Melo A, et al. Bedside estimation of recruitable alveolar collapse and hyperdistension by electrical impedance tomography. Intensive Care Med. 2009;35(6):1132-1137.9. Riera J, Pérez P, Cortés J, Roca O, Masclans JR, Rello J. Effect of high-flow nasal cannula and body position on end-expiratory lung volume: a cohort study using electrical impedance tomography. Respir Care. 2013;58(4):589-596.10. Wisse JJ, Goos TG, Jonkman AH, et al. Electrical impedance tomography as a monitoring tool during weaning from mechanical ventilation: an observational study during the spontaneous breathing trial. Respir Res. 2024;25(1):179.