Due to copyright issues, an electronic copy of the thesis must be ordered from the faculty. For the faculty to have time to process the order, the order must be received by the faculty at the latest 2 days before the public defence. Orders received later than 2 days before the defence will not be processed. After the public defence, please address any inquiries regarding the thesis to the candidate.
Trial Lecture – time and place
See Trial Lecture.
Adjudication committee
- First opponent: Professor Mark Davis, Mayo Clinic, USA
- Second opponent: Senior Research Coordinator Maria Ewerlöf, Linköping University, Sweden
- Third member and chair of the evaluation committee: Associate Professor John-Peder Escobar Kvitting, University of Oslo
Chair of the Defence
Professor Emeritus Truls Erik Bjerklund Johansen, University of Oslo
Principal Supervisor
Professor II Pål Dag Line, University of Oslo
Summary
All cells depend on continuous oxygen supply to sustain metabolism. Lung failure, heart failure and misdistribution of cardiac output can result in tissue hypoxia – leading to cell death, organ dysfunction and mortality. No routine methods have up to now been available for measurements of capillary oxygen delivery.
Oxygen is delivered via capillaries, characterized by a thin wall facilitating oxygen diffusion to surrounding cells. Skin sub-epidermal nutritive capillaries, supplying proliferating stem cells located in the epidermal basal membrane, are – like nutritive capillaries in other tissues– regulated by non-innervated pericytes.
In her research, Liv K. Wikslund and collaborators have used a novel, non-invasive, optical technology platform developed in Norway (ODI-Tech®), integrating microscopy and spectroscopy, to assess oxygen delivery from skin nutritive capillaries. The main aim of the thesis was to develop a trauma model, used to characterize the sensitivity of the platform by describing local microvascular responses to healing of a small skin incision. The technology was then used to study oxygen delivery from skin capillaries in a patient cohort hospitalized with Covid-19.
Paper I-III, confirmed the sensitivity of the platform to describe physiological microcirculatory responses – translated into increased capacity for microvascular oxygen delivery – during wound healing in healthy volunteers.
In paper IV, the method was applied to 40 patients hospitalized for COVID-19 at Mass General Hospital, Boston, USA. The results showed peripheral microvascular dysregulation leading to tissue hypoxia, with most severe hypoxia in patients dying from COVID-19. Based on the findings we hypothesize that hypoxia coexisting in other tissues (e.g. the brain) contributes to both reversible and non-reversible long COVID symptoms, as well as mortality. The results further indicates that the platform has a great potential for early disease detection and improve personalized treatment approaches across a broad spectrum of medical conditions linked to compromised oxygen delivery.
Additional information
Contact the research support staff.