Evidence supporting the use of microdialysis data to determine clinical outcome

Study	Population	N	Methods	Findings
Timofeev et al., 2011	TBI	223	Analyte values averaged for each patient on each post injury day. Outcome with 6 month GOS, GOS 1, 2–3, 4–5, univariate, non parametric analysis and multivariate logistic regression	Glutamate and L/P ratio higher in patients who died or had an unfavorable outcome compared to those with good outcome. Glucose, pyruvate, and L/P ratio were significant predictors of mortality
Chamoun et al., 2010	TBI	165	Microdialysis probe placed in tissue near PO2 probe, hourly dialysate samples collected. Multivariate analysis with logistic regression to identify factors associated with Outcome (6 month GOS)	Two patterns of glutamate levels were identified. (1) Levels that decreased over time (2) Glutamate increased or remained abnormally elevated over time Mortality was associated with pattern 2
Stein et al., 2012	TBI	89	Multivariate model to identify factors associated with GOSe at 6 months. Metabolic crisis defined as Glu < 0.8 mmol/L and LPR > 25	The length of time in metabolic crisis was significantly associated with outcome. The OR for poor outcome for 12 h of metabolic crisis was 2.16(CI 1.05–4.45 p = 0.036)
Nagel et al., 2009	SAH	192	Multivariate analysis to identify factors associated with 12 month GOS in patients with low ICP after SAH versus high ICP	Elevated Glutamate and L/P ratio were associated with worse 12 month GOS and were more common in the high ICP group. The majority of patients with elevated ICP displayed abnormal microdialysis pattern before the rise in ICP
Oddo et al., 2012	SAH	31	Episodes of elevated brain lactate were divided into two groups. Those with a low brain tissue oxygen (hypoxic) and normal tissue oxygen (hyperglycolytic). Outcome using dichotomized mRS	Episodes of hypoxic elevations in brain lactate were associated with mortality while episodes of hyperglycolytic lactate were strong predictors of good outcome
Nikaina et al., 2012	ICH	27	Linear regression model to evaluate the relationship between CPP + L/P ratio and 6 month outcome measured by GOS	The combination of CPP > 75 and L/P < 36 was associated with a favorable 6 month GOS p = .054