There is a need for biological markers of the acute respiratory distress syndrome (ARDS). Exhaled... more There is a need for biological markers of the acute respiratory distress syndrome (ARDS). Exhaled breath contains hundreds of metabolites in the gas phase, some of which reflect (patho)physiological processes. We aimed to determine the diagnostic accuracy of metabolites in exhaled breath as biomarkers of ARDS. Breath from ventilated intensive care unit patients (n=101) was analysed using gas chromatography and mass spectrometry during the first day of admission. ARDS was defined by the Berlin definition. Training and temporal validation cohorts were used. 23 patients in the training cohort (n=53) had ARDS. Three breath metabolites, octane, acetaldehyde and 3-methylheptane, could discriminate between ARDS and controls with an area under the receiver operating characteristic curve (AUC) of 0.80. Temporal external validation (19 ARDS cases in a cohort of 48) resulted in an AUC of 0.78. Discrimination was insensitive to adjustment for severity of disease, a direct or indirect cause of ARDS, comorbidities, or ventilator settings. Combination with the lung injury prediction score increased the AUC to 0.91 and improved net reclassification by 1.17. Exhaled breath analysis showed good diagnostic accuracy for ARDS, which was externally validated. These data suggest that exhaled breath analysis could be used for the diagnostic assessment of ARDS.
International Journal of Behavioral Medicine, 2014
Magnetic Resonance Imaging (MRI) is associated with high levels of anxiety in many patients which... more Magnetic Resonance Imaging (MRI) is associated with high levels of anxiety in many patients which may interfere with image quality and increase examination time. In order to develop effective intervention strategies that decrease anxiety, more insights into moments of high anxiety during a MRI examination are necessary. The present study aimed at obtaining insights into anxiety levels and moments of high anxiety during a Magnetic Resonance Imaging examination. The study included 67 patients, of whom 52 (77.6 %) were categorized as highly anxious. Stress and anxiety were measured continuously throughout the entire duration of the MRI examination by monitoring the heart rate. An increase in heart rate during the scan was taken as an indication for higher stress and anxiety. In addition to measuring stress and anxiety objectively, anxiety was assessed subjectively before and after the procedure by means of self-report questionnaires. The self-report data indicate that patients were highly anxious before the MRI examination. Moreover, the electrophysiological data clearly show that anxiety levels were highest at the beginning of the procedure, i.e., when the MRI table moved into the scanner, and then decreased over the course of the examination. Furthermore, the findings show that while subjectively measured anxiety was higher in patients who had taken anxiolytics prior to the MRI examination than in patients who had not taken any anxiolytics, objectively measured anxiety during the scan was equally high in both groups. The present study provides detailed insights into the anxiety levels during an MRI examination, which may aid in developing effective anxiety-reduction strategies. Additionally, the findings show that measuring anxiety continuously throughout the entire examination using electrophysiology in combination with measuring anxiety subjectively prior to and after the scan provides a more complete assessment of MRI-related anxiety.
Alkanes and alkenes in the breath are produced through fatty acid peroxidation, which is initiali... more Alkanes and alkenes in the breath are produced through fatty acid peroxidation, which is initialized by reactive oxygen species. Inflammation is an important cause and effect of reactive oxygen species. We aimed to evaluate the association between fatty acid peroxidation products and inflammation of the alveolar and systemic compartment in ventilated intensive care unit (ICU) patients.Volatile organic compounds were measured by gas chromatography and mass spectrometry in the breath of newly ventilated ICU patients within 24 h after ICU admission. Cytokines were measured in non-directed bronchial lavage fluid (NBL) and plasma by cytometric bead array. Correlation coefficients were calculated and presented in heatmaps.93 patients were included. Peroxidation products in exhaled breath were not associated with markers of inflammation in plasma, but were correlated with those in NBL. IL-6, IL-8, IL-1β and TNF-α concentration in NBL showed inverse correlation coefficients with the peroxidation products of fatty acids. Furthermore, NBL IL-10, IL-13, GM-CSF and IFNγ demonstrated positive associations with breath alkanes and alkenes. Correlation coefficients for NBL cytokines were high regarding peroxidation products of n-6, n-7 and particularly in n-9 fatty acids.Levels of lipid peroxidation products in the breath of ventilated ICU patients are associated with levels of inflammatory markers in NBL, but not in plasma. Alkanes and alkenes in breath seems to be associated with an anti-inflammatory, rather than a pro-inflammatory state in the alveoli.
In this case study, we designed a family game to explore whether this could be an effective and f... more In this case study, we designed a family game to explore whether this could be an effective and fun approach for raising the awareness of family members towards their energy use and, in the long run, to provide an effective tool for affecting their habits regarding sustainable behavior. The design of the family game implemented the metaphor of electricity as
During a magnetic resonance imaging (MRI) examination, patients are required to remain still to m... more During a magnetic resonance imaging (MRI) examination, patients are required to remain still to minimize motion that may compromise image quality and may make rescanning necessary. It is often assumed that anxiety, which is experienced by a considerable number of patients undergoing an MR examination, increases motion and decreases image quality. The present study explores the relationship between anxiety and movement of patients during an MR examination. Anxiety was measured subjectively by means of the State Anxiety Inventory and a visual analogue scale for claustrophobia. Motion and image quality were measured in three different ways. First, software was used that allows an estimation of motion based on tracker scans between the clinical scans. Second, the MRI technician who performed the MR examination was asked to indicate the degree of motion artifacts and image quality for each patient. Third, after all scans had been collected, two radiologists evaluated each clinical scan. No or low correlations between anxiety and the distinct measures of motion and image quality were found for all three measures. This finding shows that there is little evidence for the assumption that anxiety increases motion and decreases image quality during an MR examination.
There is a need for biological markers of the acute respiratory distress syndrome (ARDS). Exhaled... more There is a need for biological markers of the acute respiratory distress syndrome (ARDS). Exhaled breath contains hundreds of metabolites in the gas phase, some of which reflect (patho)physiological processes. We aimed to determine the diagnostic accuracy of metabolites in exhaled breath as biomarkers of ARDS. Breath from ventilated intensive care unit patients (n=101) was analysed using gas chromatography and mass spectrometry during the first day of admission. ARDS was defined by the Berlin definition. Training and temporal validation cohorts were used. 23 patients in the training cohort (n=53) had ARDS. Three breath metabolites, octane, acetaldehyde and 3-methylheptane, could discriminate between ARDS and controls with an area under the receiver operating characteristic curve (AUC) of 0.80. Temporal external validation (19 ARDS cases in a cohort of 48) resulted in an AUC of 0.78. Discrimination was insensitive to adjustment for severity of disease, a direct or indirect cause of ARDS, comorbidities, or ventilator settings. Combination with the lung injury prediction score increased the AUC to 0.91 and improved net reclassification by 1.17. Exhaled breath analysis showed good diagnostic accuracy for ARDS, which was externally validated. These data suggest that exhaled breath analysis could be used for the diagnostic assessment of ARDS.
International Journal of Behavioral Medicine, 2014
Magnetic Resonance Imaging (MRI) is associated with high levels of anxiety in many patients which... more Magnetic Resonance Imaging (MRI) is associated with high levels of anxiety in many patients which may interfere with image quality and increase examination time. In order to develop effective intervention strategies that decrease anxiety, more insights into moments of high anxiety during a MRI examination are necessary. The present study aimed at obtaining insights into anxiety levels and moments of high anxiety during a Magnetic Resonance Imaging examination. The study included 67 patients, of whom 52 (77.6 %) were categorized as highly anxious. Stress and anxiety were measured continuously throughout the entire duration of the MRI examination by monitoring the heart rate. An increase in heart rate during the scan was taken as an indication for higher stress and anxiety. In addition to measuring stress and anxiety objectively, anxiety was assessed subjectively before and after the procedure by means of self-report questionnaires. The self-report data indicate that patients were highly anxious before the MRI examination. Moreover, the electrophysiological data clearly show that anxiety levels were highest at the beginning of the procedure, i.e., when the MRI table moved into the scanner, and then decreased over the course of the examination. Furthermore, the findings show that while subjectively measured anxiety was higher in patients who had taken anxiolytics prior to the MRI examination than in patients who had not taken any anxiolytics, objectively measured anxiety during the scan was equally high in both groups. The present study provides detailed insights into the anxiety levels during an MRI examination, which may aid in developing effective anxiety-reduction strategies. Additionally, the findings show that measuring anxiety continuously throughout the entire examination using electrophysiology in combination with measuring anxiety subjectively prior to and after the scan provides a more complete assessment of MRI-related anxiety.
Alkanes and alkenes in the breath are produced through fatty acid peroxidation, which is initiali... more Alkanes and alkenes in the breath are produced through fatty acid peroxidation, which is initialized by reactive oxygen species. Inflammation is an important cause and effect of reactive oxygen species. We aimed to evaluate the association between fatty acid peroxidation products and inflammation of the alveolar and systemic compartment in ventilated intensive care unit (ICU) patients.Volatile organic compounds were measured by gas chromatography and mass spectrometry in the breath of newly ventilated ICU patients within 24 h after ICU admission. Cytokines were measured in non-directed bronchial lavage fluid (NBL) and plasma by cytometric bead array. Correlation coefficients were calculated and presented in heatmaps.93 patients were included. Peroxidation products in exhaled breath were not associated with markers of inflammation in plasma, but were correlated with those in NBL. IL-6, IL-8, IL-1β and TNF-α concentration in NBL showed inverse correlation coefficients with the peroxidation products of fatty acids. Furthermore, NBL IL-10, IL-13, GM-CSF and IFNγ demonstrated positive associations with breath alkanes and alkenes. Correlation coefficients for NBL cytokines were high regarding peroxidation products of n-6, n-7 and particularly in n-9 fatty acids.Levels of lipid peroxidation products in the breath of ventilated ICU patients are associated with levels of inflammatory markers in NBL, but not in plasma. Alkanes and alkenes in breath seems to be associated with an anti-inflammatory, rather than a pro-inflammatory state in the alveoli.
In this case study, we designed a family game to explore whether this could be an effective and f... more In this case study, we designed a family game to explore whether this could be an effective and fun approach for raising the awareness of family members towards their energy use and, in the long run, to provide an effective tool for affecting their habits regarding sustainable behavior. The design of the family game implemented the metaphor of electricity as
During a magnetic resonance imaging (MRI) examination, patients are required to remain still to m... more During a magnetic resonance imaging (MRI) examination, patients are required to remain still to minimize motion that may compromise image quality and may make rescanning necessary. It is often assumed that anxiety, which is experienced by a considerable number of patients undergoing an MR examination, increases motion and decreases image quality. The present study explores the relationship between anxiety and movement of patients during an MR examination. Anxiety was measured subjectively by means of the State Anxiety Inventory and a visual analogue scale for claustrophobia. Motion and image quality were measured in three different ways. First, software was used that allows an estimation of motion based on tracker scans between the clinical scans. Second, the MRI technician who performed the MR examination was asked to indicate the degree of motion artifacts and image quality for each patient. Third, after all scans had been collected, two radiologists evaluated each clinical scan. No or low correlations between anxiety and the distinct measures of motion and image quality were found for all three measures. This finding shows that there is little evidence for the assumption that anxiety increases motion and decreases image quality during an MR examination.
Uploads
Papers by Hans Weda