Kayambu G.1,2, Pfluger C.M.3, Lin C.3, Boots R.J.1,4, Paratz J.D.1,5
1The University of Queensland, Burns, Trauma & Critical Care Research Centre, School of Medicine, Brisbane, Australia, 2National University Hospital, Department of Rehabilitation, Brisbane, Australia, 3University of Queensland Centre for Clinical Research, Faculty of Medicine, Brisbane, Australia, 4The Royal Brisbane and Women's Hospital, Department of Intensive Care, Brisbane, Australia, 5Griffith University, School of Allied Health Sciences, Brisbane, Australia
Background: Critically ill patients with sepsis are prone to oxidative stress. Oxidative stress may have effects on mitochondrial DNA and potentially cause harmful outcomes. Early exercise in patients with sepsis may contribute to this effect.
Purpose: To determine if early physical rehabilitation causes oxidative stress in patients with sepsis syndromes.
Methods: Forty-five critically ill adults admitted to a general intensive care unit with sepsis syndromes completed a pilot study on oxidative stress as part of a prospective double blinded randomised controlled trial investigating early physical rehabilitation. Clinical demographic data and relative mitochondrial DNA (mtDNA)/nuclear DNA (nDNA) were collected at baseline and thereafter for 2 weeks during ICU admission. Arterial plasma lactate was measured for anaerobic glycolysis.
Results: A mixed method ANOVA for repeated measures found no significance found for time or time*group at baseline (n=30) and week 1(+/- Day 4) (n=27). At week 1, there was no change in the mtDNA/nDNA ratio following ICU exercise in the intervention group (0.74). At week 1(+/- Day 4) mtDNA/nDNA ratio significantly correlated with plasma lactate concentration on Day 4 of exercise (r=0.39, p=0.04) with plasma lactate showing no significant change with early exercise over week 1 of ICU admission.
Conclusion(s): Early exercise in the ICU does not appear to increase oxidative stress in acute sepsis syndromes as assessed by mitochondrial DNA or cause anaerobic glycolysis. The utility of mtDNA as a marker of oxidative stress for clinical outcome requires further investigation.
Implications: Early physical rehabilitation is safe based on blood lactate response and does not appear to cause any harm in relation to oxidative stress in critically ill patients. A larger study is required to assess for temporal trends on the effects of exercise on oxidative stress. Further investigations are required to elucidate the mechanism of oxidative stress of early exercise during critical illness. This will aid to refine and tailor safer approaches to physical rehabilitation in the intensive care.
Funding acknowledgements: Intensive Care Foundation
National University Hospital
National University Hospital
Topic: Critical care
Ethics approval: The Human Research Ethics Committee; Royal Brisbane and Womens Hospital Medical Research Ethics Committee; The University of Queensland
All authors, affiliations and abstracts have been published as submitted.
