Alteration of Leukocyte Count Correlates with Increased Pulmonary Vascular Permeability and Decreased PaO2:FiO2 Ratio Early after Major Burns

Abstract

Leukocytes are activated systemically and their numbers increase soon after a burn followed by a rapid decline to low normal or subnormal levels, possibly by increased extravasation. Experimental data support that an important target for such extravasation is the lungs and that leukocytes when they adhere to endothelial cells cause an increase in vascular permeability. The authors investigated a possible relation between early increased pulmonary vascular permeability or a decreased PaO2:FiO2 ratio and the dynamic change in concentration of blood leukocytes after a burn. This is a prospective, exploratory, single-center study. The authors measured the dynamic changes of leukocytes in blood starting early after the burn, pulmonary vascular permeability index by thermodilution, and PaO2:FiO2-ratios in 20 patients during the first 21 days after a major burn (>20% TBSA%). Median TBSA was 40% interquartile range (IQR, 25-52) and full thickness burn 28% (IQR, 2-39). There was a correlation between the early (<24 hours) alteration in white blood cell count and both early increased pulmonary vascular permeability (r =.63, P =.004) and the decreased oxygenation index defined as PaO2:FiO2< 27 kPa (P =.004). The authors have documented a correlation between dynamic change of blood leukocytes and pulmonary failure early after burns.