Simon Mølstrøm

What is the title of your thesis?

Bedside Assessment of Global Cerebral Energy Metabolism utilizing Intravenous Microdialysis:
With special reference to post-cardiac arrest care

From which institute and/or research unit did you make your PhD thesis?

Department of Anesthesiology and Intensive Care, Odense University Hospital, Denmark. Department of Clinical Research, University of Southern Denmark, Odense, Denmark

Main Supervisor

Palle Toft, Professor, MD, Ph.D., Professor.

What question did you wish to answer with your thesis?

This thesis´ overall objectives were assessment of optimal blood pressure and characterizing changes in global cerebral energy metabolism using novel bedside microdialysis application in comatose patients resuscitated from OHCA.

How did you do it?

A feasibility study was designed to investigate whether jugular bulb microdialysis (JBM) might be used to monitor secondary deterioration of cerebral energy metabolism after out-of-hospital cardiac arrest (OHCA). The study indicated that JBM was feasible and safe. Variables reflecting cerebral energy metabolism could be distinguished from systemic variables obtained from intraarterial microdialysis in patients with poor clinical outcome. Biochemical signs of ischemia and mitochondrial dysfunction were frequent and long-lasting after the return of spontaneous circulation (ROSC) and more pronounced in patients with unfavorable outcome.
The main study aimed at assessing the effect of different blood pressure levels on global cerebral energy metabolism in comatose patients resuscitated from OHCA. In this double-blinded trial, 60 comatose OHCA patients were randomly assigned to low (63 mmHg) or high (77 mmHg) MAP. Targeting a higher MAP 180 min after ROSC did not significantly improve cerebral energy metabolism or oxygenation within 96 hours of post-resuscitation care. We could predict poor neurological outcome based on specific metabolic patterns obtained by JBM.

How can your research be used (in the clinic/society etc.)?

Future efforts to improve outcomes after OHCA may focus on individualized treatment that augments cerebral perfusion and energy metabolism assessed by JBM, during early post-resuscitation care. Individualized brain resuscitation strategies that prevent secondary brain injury may include, e.g. increasing blood pressure, optimizing cardiac output and modifying PaO2 and PaCO2.
If JBM is initiated within the first hour after ROSC, it may be possible to identify patients with inadequate cerebral reperfusion prior to irreversible cell damage.
In the future, this multimodal approach might optimize brain metabolism and individualize the treatment of post-cardiac arrest patients suffering from secondary ischemia, mitochondrial dysfunction and potentially improve outcomes. Time to drop 'one-size-fits-all' hemodynamic targets?