title: Feasibility of intercostal blood flow measurement by echo-Doppler technique in healthy subjects.
abstract: Intercostal artery blood flow supplies the external and internal intercostal muscles, which are inspiratory and expiratory muscles. Intercostal blood flow measured by the echo-Doppler (ED) technique has not previously been reported in humans. This study describes the feasibility of this measurement during free and loaded breathing in healthy subjects. Systolic, diastolic and mean blood flows were measured in the eighth dorsal intercostal space during free and loaded breathing using the ED technique. Flows were calculated as the product of the artery intraluminal surface and blood velocity. Ten healthy subjects (42 ± 13·6 years) were included. Integrated electromyogram (iEMG), arterial pressure, cardiac frequency and breathing pattern were also recorded. Mean blood flows were 3·5 ± 1·2 ml min-1at rest, 6 ± 2·6 ml min-1while breathing through a combined inspiratory and expiratory resistance and 4·0 ± 1·3 ml min-11 min after unloading. Diastolic blood flow was about one-third the systolic blood flow. The changes in blood flows were consistent with those in iEMG. No change in mean blood flow was observed between inspiration and expiration, suggesting a balance in the perfusion of external and internal muscles during breathing. In conclusion, ED is a feasible technique for non-invasive, real-time measurement of intercostal blood flow in humans. In healthy subjects, mean blood flow appeared tightly matched to iEMG activity. This technique may provide a way to assess the vascular adaptations induced by diseases in which respiratory work is increased or cardiac blood flow altered.
authors.affiliation: Laboratoire 'MOVE', Université de Poitiers, UPRES-EA 6314, France.
authors.forename: Claire
authors.initials: C
authors.lastname: de Bisschop
authors.affiliation: Unité d'imagerie thoracique et cardiovasculaire (Pr Laurent), Hôpital du Haut-Lévêque, CHU de Bordeaux, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Montaudon
authors.affiliation: Laboratoire de physiologie, Université de Bordeaux, Bordeaux Cedex, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Glénet
authors.affiliation: Laboratoire de physiologie, Université de Bordeaux, Bordeaux Cedex, France.
authors.forename: Hervé
authors.initials: H
authors.lastname: Guénard
mesh_terms: D000328:Adult; D000403:Airway Resistance; D062186:Arterial Pressure; D001158:Arteries / Q000000981:diagnostic imaging*; D001783:Blood Flow Velocity; D004576:Electromyography; D005240:Feasibility Studies; D005260:Female; D064368:Healthy Volunteers; D006339:Heart Rate; D006801:Humans; D007366:Intercostal Muscles / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012039:Regional Blood Flow; D015203:Reproducibility of Results; D015656:Respiratory Mechanics; D018608:Ultrasonography, Doppler
keywords: arterial blood flow; electromyography; humans; intercostal muscle; loaded breathing