Effect of bronchial artery blood flow on cardiopulmonary bypass-induced lung injury

• Published in: American journal of physiology. Heart and circulatory physiology 2004-02, Vol.286 (2), p.H693-H700
• Main Authors: Dodd-o, Jeffrey M, Welsh, Laura E, Salazar, Jorge D, Walinsky, Peter L, Peck, Eric A, Shake, Jay G, Caparrelli, David J, Bethea, Brian T, Cattaneo, Stephen M, Baumgartner, William A, Pearse, David B
• Format: Article
• Language: English
• Subjects: Analysis of Variance; Animals; Body Weight; Bronchial Arteries - physiology; Cardiopulmonary Bypass - adverse effects; Lung - blood supply; Lung Injury; Models, Animal; Muscle, Smooth, Vascular - physiology; Regional Blood Flow; Swine; Time Factors
• ISSN: 0363-6135; 1522-1539
• DOI: 10.1152/ajpheart.00888.2003

1 Department of Anesthesia and Critical Care, 2 Division of Pulmonary and Critical Care Medicine, Department of Medicine, and 3 Division of Cardiac Surgery, Department of Surgery, The Johns Hopkins Medical Institutions, Baltimore, Maryland 21224 Submitted 16 September 2003 ; accepted in final form 13 October 2003 Cardiovascular surgery requiring cardiopulmonary bypass (CPB) is frequently complicated by postoperative lung injury. Bronchial artery (BA) blood flow has been hypothesized to attenuate this injury. The purpose of the present study was to determine the effect of BA blood flow on CPB-induced lung injury in anesthetized pigs. In eight pigs (BA ligated) the BA was ligated, whereas in six pigs (BA patent) the BA was identified but left intact. Warm (37°C) CPB was then performed in all pigs with complete occlusion of the pulmonary artery and deflated lungs to maximize lung injury. BA ligation significantly exacerbated nearly all aspects of pulmonary function beginning at 5 min post-CPB. At 25 min, BA-ligated pigs had a lower arterial P O 2 at a fraction of inspired oxygen of 1.0 (52 ± 5 vs. 312 ± 58 mmHg) and greater peak tracheal pressure (39 ± 6 vs. 15 ± 4 mmHg), pulmonary vascular resistance (11 ± 1 vs. 6 ± 1 mmHg·l –1 ·min), plasma TNF- (1.2 ± 0.60 vs. 0.59 ± 0.092 ng/ml), extravascular lung water (11.7 ± 1.2 vs. 7.7 ± 0.5 ml/g blood-free dry weight), and pulmonary vascular protein permeability, as assessed by a decreased reflection coefficient for albumin ( alb ; 0.53 ± 0.1 vs. 0.82 ± 0.05). There was a negative correlation ( R = 0.95, P < 0.001) between alb and the 25-min plasma TNF- concentration. These results suggest that a severe decrease in BA blood flow during and after warm CPB causes increased pulmonary vascular permeability, edema formation, cytokine production, and severe arterial hypoxemia secondary to intrapulmonary shunt. pulmonary edema; reflection coefficient; pig; ischemia; extracorporeal perfusion; tumor necrosis factor- ; interleukin-6 Address for reprint requests and other correspondence: D. B. Pearse, Div. of Pulmonary and Critical Care Medicine, The Asthma and Allergy Center, 5501 Hopkins Bayview Circle, Baltimore, MD 21224 (E-mail: dpearse{at}jhmi.edu ).