Bedside Measurement of Volatile Organic Compounds in the Atmosphere of Neonatal Incubators Using Ion Mobility Spectrometry

Abstract

Background: Early and non-invasive diagnosis of common diseases is of great importance in the care of preterm infants. We hypothesized that volatile organic compounds (VOC) can be successfully measured in the neonatal incubator atmosphere. Methods: This is a feasibility study to investigate whether the discrimination of occupied and unoccupied neonatal incubators is possible by bedside measurement of volatile organic compounds (VOCs) on the neonatal intensive care unit. VOC profiles were measured in the incubator air using ion mobility spectrometry coupled to multi-capillary columns (BreathDiscovery B&S Analytik GmbH, Dortmund, Germany). Results: Seventeen incubators occupied by preterm infants (50 measurements) and nine unoccupied neonatal incubators were sampled, using 37 room air measurements as controls. Three VOC signals that allow the discrimination between occupied and unoccupied incubators were identified. The best discrimination was reached by peak P20 exhibiting a sensitivity, specificity, positive predictive value and negative predictive value of 94.0, 88.9, 97.3, and 72.3%, respectively. Use of a decision tree improved these values to 100.0, 88.9, 98.0, and 100.0%, respectively. Discussion: A bedside method that allows the characterization of VOC profiles in the neonatal incubator atmosphere using ion mobility spectrometry was established. Occupied and unoccupied incubators could be discriminated by characterizing VOC profiles. This technique has the potential to yield results within minutes. Thus, future studies are recommended to test the hypothesis that VOCs within neonatal incubators are useful biomarkers for non-invasive diagnostics in preterm neonates.

Detection of Volatile Organic Compounds as Potential Novel Biomarkers for Chorioamnionitis – Proof of Experimental Models

“…The device and sampling parameters are given in Supplementary Table 1. The methods for VOC analysis were published earlier (36). A laboratory bottle (100 mL) heated to 37 • C served as a sample container.…”

“…Another tube connected the cap of the small laboratory bottle and the Sampling Input of MCC/IMS device. Synthetic air was used to exclude contamination with environmental VOCs as previously published (36).…”

“…The MCC/IMS data were evaluated using the software Visual Now 2.5 (B & S Analytik, Dortmund Germany) as previously reported (36). All peaks were characterized by their specific combination of position retention time per second and drift time (corresponding 1/K0-value) (45)(46)(47)(48)(49).…”

“…Ion mobility spectrometry (IMS), which allows the detection of VOCs in lower ppb v (parts per billion by volume) to ppt v (parts per trillion by volume) (ng L −1 to pg L −1 ) range, have been successfully used for the non-invasive diagnosis of several diseases. Using IMS coupled to multi-capillary columns (MCC/IMS) we have previously established a bedside method that allows the characterization of VOC profiles in the neonatal incubator atmosphere (36).…”

Volatile organic compounds as disease predictors in newborn infants: a systematic review

“…In a single-centre study, Steinbach et al [31] measured VOCs in 9 occupied and 17 unoccupied neonatal incubators (all preterm infants) using ion-mobility spectrometry. The authors were successful in identifying discriminating VOC profiles from occupied and unoccupied incubators using principal component and decision tree analysis.…”