NEUTROPHIL SEQUESTRATION IN LUNGS REMOVED AT SURGERY - THE EFFECT OF MICROSCOPIC EMPHYSEMA

Neutrophils within the lungs are considered to play an important role in the pathogenesis of pulmonary emphysema. We have studied the intrav ascular distribution of reinjected autologous In-111-labeled neutrophi ls in lung specimens resected 10 min after reinjection from 10 patient s undergoing surgery for peripheral bronchogenic tumors. An excess of neutrophils relative to that expected for the Tc-99m-labeled erythrocy te blood volume was confirmed in all specimens (range, 3- to 136-fold) . In seven specimens which were completely examined, this excess displ ayed a skewed distribution, with a median neutrophil sequestration of 20-fold excess, and correlated with local blood volume (r = - 0.51; p < 0.001). There was also a significant correlation between alveolar wa ll surface area per unit volume of lung (AWUV) and neutrophil excess, when randomly selected tissue blocks from each specimen were analyzed (r = 0.34, n = 51, p = 0.012). This same trend was demonstrated when w hole specimen median values were considered (r = 0.64, n = 7, p = 0.07 ). Thus in areas of the lungs with lower AWUV values (increasing micro scopic emphysema), fewer neutrophils were present. These studies add f urther support to the view that emphysema per se is not associated wit h an increased sequestration of pulmonary intravascular neutrophils.