Description of mitochondrial oxygen tension and its variability in healthy volunteers.

Abstract

ObjectivesDescribing mitochondrial oxygenation (mitoPO2) and its within- and between-subject variability over time after 5-aminolevulinic acid (ALA) plaster application in healthy volunteers.DesignProspective cohort study.SettingMeasurements were performed in Leiden University Medical Center, the Netherlands.ParticipantsHealthy volunteers enrolled from July to September 2020.InterventionsTwo ALA plasters were placed parasternal left and right, with a 3-hour time interval, to examine the influence of the calendar time on the value of mitoPO2. We measured mitoPO2 at 4, 5, 7, 10, 28, and 31 hours after ALA plaster 1 application, and at 4, 5, 7, 25, and 28 hours after ALA plaster 2 application.Primary and secondary outcome measuresAt each time point, five mitoPO2 measurements were performed. Within-subject variability was defined as the standard deviation (SD) of the mean of five measurements per timepoint of a study participant. The between-subject variability was the SD of the mean mitoPO2 value of the study population per timepoint.ResultsIn 16 completed inclusions, median mitoPO2 values and within-subject variability were relatively similar over time at all time points for both plasters. An increase in overall between-subject variability was seen after 25 hours ALA plaster time (19.6 mm Hg vs 23.9 mm Hg after respectively 10 and 25 hours ALA plaster time).ConclusionsThe mitoPO2 values and within-subject variability remained relatively stable over time in healthy volunteers. An increase in between-subject variability was seen after 25 hours ALA plaster time warranting replacement of the ALA plaster one day after its application.Trial registrationClinicalTrials.gov with trial number NCT04626661.