Dynamic Pulmonary Accumulation of Labelled Neutrophils by Blood Membrane Contact in the Pig

Abstract

Nine anesthetized pigs were subjected to short (90 min) sham dialysis with blood membrane contact with the aim to select effects of the artificial surface during dialysis. The importance of the neutrophil (PMN) was investigated by the selective isotope labelling, dynamically followed by γ-camera imaging and biochemical assays specifically oriented for PMN function. These assays included cell count, PMN aggregation, PMN luminescence, fibronectin and catalase activity. Aditionally, pulmonary and systemic hemodynamics and acid base balance were monitored. Sham dialysis induced an accumulation of labelled PMN attaining a maximum between 15 and 17 min. This was coupled with a time-related neutropenia, pulmonary vasoconstriction, increased in vitro PMN aggregation and luminescence response. The neutrophil response abated by the end of dialysis. Cardiac output and arterial blood pressure declined to a steady level after 30 min of sham dialysis. There was an insignificant decrease in catalase activity. All other parameters remained unaltered. The results indicate that PMN accumulates in the pulmonary vessels, in association with neutropenia and activation. The transience of the event points to a protective mechanisms of humoral and/or cellular character.

Increased Pulmonary Platelet Sequestration Due to Infusion of Cold Saline during Extracorporeal Circulation

“…We have previously shown that PMNs aggregate in the lungs quickly after the start of dialysis, reaching a maximum after 10-15 min and simultaneously a drop in the PMN count in peripheral blood occurs [3]. A rise in PAP was noted prior to the increase in PMN sequestration.…”

“…Mean systemic blood pressure (MAP) and heart rate were monitored continuously via a catheter in the left carotid artery. Blood samples for peripheral cell count including white blood cells, red blood cells and platelets were obtained from dialysis tubings and analyzed as previously described [3], Arterial and pulmonary blood samples for determination of blood gases and saturation were ob tained from the neck catheters and analyzed by standardized labora tory techniques. After a period of stabilization and baseline determina tion a sham dialysis using cuprophan hollow-liber dialysers (0.80 m2) was commenced and continued for 60 min as previously described [3].…”

“…dialysis mem brane, induces powerful cellular and humoral defence mechanisms. Complement and contact activation is most likely responsible for the neutropenia and thrombocytope nia that develops during the first hour of dialysis; events that are reversed in the latter part of dialysis through demargination and/or cell proliferation [1,2], One of the main target organs of cell accumulation is the lung [3], and in the and group 2 (solid line) during dialysis. M eans±SE ; *p<0.0l be tween groups.…”

Dynamic accumulation of neutrophils in lungs and visceral organs during early abdominal sepsis in the pig

“…We have previously shown that neutrophils become sequestered in the lungs early after trauma and the beginning of dialysis [5,10]. Although clinical signs of respiratory insufficiency during the early phase of sepsis are usually not seen, it could be hypothezised that the activation and pulmonary sequestration of PMNs occurs at this early stage [7].…”

Peripheral circulatory effects of pump perfusion on cat skeletal muscle with and without prostacyclin

“…Extracorporeal circulation also seems to influence the blood cells, causing aggregation and accumulation of platelets and neutrophiles Correspondence : Dr John Jahr, Department of Physiology and Neuroscience, University of Lund, So$ lvegatan 19, S-223 62 Lund, Sweden. (Colman 1990, Ma/ rtensson et al 1990, as well as interfering with the normal coagulation system (Webb et al 1995, Edmunds 1993) and generating complement activation (Blomquist et al 1991, Kirschfink et al 1993. Some of these questions were addressed by us in a previous experimental study (Jahr & Gra$ nde 1992), in which we showed that long-term extracorporeal veno-venous circulation including a roller-pump had severe adverse effects in terms of respiratory insufficiency, platelet consumption, transcapillary leakage and acidemia and that these adverse effects were partly counteracted by prostacyclin.…”