Electrical impedance segmentography: A promising tool for respiratory monitoring?

Abstract. 

BACKGROUND: Non-invasive, radiation free bedside monitoring methods have gained increased popularity in the respiratory field. The aim of our study was to report the experience with electrical impedance segmentography (EIS), a rather new technique, which allows continuous visual and quantitative monitoring of regional lung ventilation.

METHODS: Prospective, pilot trial in spontaneously breathing, healthy, non-sedated term neonates between 24 and 72 hours post-delivery using a commercially available EIS-device. Systematic review of the literature.

RESULTS: A total of 12 neonates were eligible for complete data analysis in our study. EIS was found to be a safe and easy to perform method. The median duration of the study time was 25 minutes (16–40). Individual total and regional impedance values, given in arbitrary units and it's percentage of distribution in the upper and lower right and left lung segments (UR, UL, LR, LL), were variable (median total impedance 207 arbitrary units (AU), UR% 17, LR 27%,UL 28%, LL 23%). A number of influencing factors such as body movements, sucking, jawing, and electrode issues have to be considered for correct data interpretation. The literature search revealed two small experimental studies in neonatal piglets and two human studies (one study in preschool children with bronchopulmonary dysplasia and one case report in a neonate with respiratory distress).

CONCLUSIONS: EIS is an innovative technique and a potentially useful tool in studying regional lung ventilation in research and clinical care. 

*Corresponding Author: 

Friedrich Reiterer, MD, Division of Neonatology, Department of Pediatrics and Adolescent Medicine, Medical University of Graz Auenbruggerplatz 38/1, 8036 Graz – Austria. Tel.: +43/0316 385 84558; Fax: +43/0316 385 12678; E-mail: friedrich.reiterer@medunigraz.at.