Angiopoietin-2, permeability oedema, occurrence and severity of ALI/ARDS in septic and non-septic critically ill patients.
BACKGROUND
Angiopoietin-2 and vascular endothelial growth factor (VEGF) may impair vascular barrier function while angiopoietin-1 may protect it. It was hypothesised that circulating angiopoietin-2 is associated with pulmonary permeability oedema and severity of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) during septic or non-septic critical illness.


METHODS
Plasma levels of angiopoietin-1 and angiopoietin-2 were measured in mechanically ventilated patients (24 with sepsis, 88 without sepsis), together with the pulmonary leak index (PLI) for 67-gallium-labelled transferrin and extravascular lung water (EVLW) by transpulmonary thermal-dye dilution as measures of pulmonary permeability and oedema, respectively. ALI/ARDS was characterised by consensus criteria and the lung injury score (LIS). Plasma VEGF and von Willebrand factor (VWF) levels were assayed.


RESULTS
Angiopoietin-2, VWF, PLI, EVLW and LIS were higher in patients with sepsis than in those without sepsis and higher in patients with ALI/ARDS (n = 10/12 in sepsis, n = 19/8 in non-sepsis) than in those without. VEGF was also higher in patients with sepsis than in those without. Patients with high PLI, regardless of EVLW, had higher angiopoietin-2 levels than patients with normal PLI and EVLW. Angiopoietin-2 correlated with the PLI, LIS and VWF levels (minimum r = 0.34, p<0.001) but not with EVLW. Angiopoietin-2 and VWF were predictive for ARDS in receiver operating characteristic curves (minimum area under the curve = 0.69, p = 0.006). Angiopoietin-1 and VEGF did not relate to the permeability oedema of ALI/ARDS.


CONCLUSIONS
Circulating angiopoietin-2 is associated with pulmonary permeability oedema, occurrence and severity of ALI/ARDS in patients with and without sepsis. The correlation of angiopoietin-2 with VWF suggests activated endothelium as a common source.
van der Heijden
M
M
Department of Physiology, VU University Medical Centre, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands. m.vanderheijden@vumc.nl
van Nieuw Amerongen
G P
GP
Koolwijk
P
P
van Hinsbergh
V W M
VW
Groeneveld
A B J
AB
D000368:Aged; D042683:Angiopoietin-1 / Q000378:metabolism; D042702:Angiopoietin-2 / Q000378:metabolism*; D016638:Critical Illness; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011654:Pulmonary Edema / Q000097:blood*; D012128:Respiratory Distress Syndrome / Q000097:blood*; D018805:Sepsis / Q000097:blood*; D042461:Vascular Endothelial Growth Factor A / Q000097:blood; D014841:von Willebrand Factor / Q000378:metabolism
D042683:Angiopoietin-1; D042702:Angiopoietin-2; D042461:Vascular Endothelial Growth Factor A; D014841:von Willebrand Factor