Morphologic CT patterns of lung injury and respiratory mechanics in H1N1 influenza

Introduction. Novel swine-origin influenza A (HlNl) was
first reported in Mexico in April 2009 and rapidly spread to
many countries around the world. Recent data indicate that the
pandemic (H1N1) virus was the dominant influenza in most
part of the world: since October 2O09, 191 countries reported
more than 375OOO laboratory confirmed cases. World Health
Organization (August 2010) reported as the most active pandenric
HlNl areas India, New Zealand and Australia, with a
decreasing incidence of new cases in the Northern hemisphere'
In our ICU M patients were admitted with HLNl severe ARDS
from Octobet iOOg to February 2010 and 15 patients fromJanuary
to Februzry 2Oll. Lung CT scan is used to evaluate iniury
morphologic pattern; according to CT appearance of severe
LROS, our patients were classified in thtee groups: D dilfuse lf
attenuations were evenly distributed throughout the lungs; 2)
focal f damage had lobar or segmental distribution established
on the recognition of anatomical structures such as the major
fissure or the interlobular septa; 3) petchy if there were lobar
or segmental areas of attenuation in some parts of the lungs
but without recognized limits in others. As reported by Abbo,
HlNl CT patterns of 21 patients from the first pandemic spread
consisted in consolidatioo (43%; ground glass opaciry (38%)
nodules (10%) and negative CT (8%).1