title: Cardiac, Respiratory and Postural Influences on Venous Return of Internal Jugular and Vertebral Veins.
abstract: It is known from physiology that heartbeat and respiration influence venous return, but little is known regarding the extent to which these two factors affect flow. In this study, we estimated the prevalence of cardiac- and breathing-induced venous flow modulations in the internal jugular vein (IJV) and vertebral vein (VV) and the effects of posture. In 19 healthy patients, neck vein flow was examined with pulsed wave Doppler. Electrocardiogram and respiratory signals were simultaneously acquired. In supine position, heart contraction always influenced venous flow, whereas breathing influenced 68% of IJV and 34% of VV flow. In sitting position, heart contraction influenced 74% of IJV and 42% of VV flow; breathing influenced 68% of IJV and 61% of VV measures. Thus, cardiac influence is greatly present in supine position, whereas breathing influence prevails in the VV while sitting. This setup allowed us to observe that in some patients, expiration may cause an unexpected increase in venous flow.
authors.affiliation: Fondazione Don Carlo Gnocchi ONLUS, IRCCS S. Maria Nascente, Milan, Italy. Electronic address: mlagana@dongnocchi.it.
authors.forename: Maria M
authors.initials: MM
authors.lastname: Laganà
authors.affiliation: Fondazione Don Carlo Gnocchi ONLUS, IRCCS S. Maria Nascente, Milan, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Di Rienzo
authors.affiliation: Fondazione Don Carlo Gnocchi ONLUS, IRCCS S. Maria Nascente, Milan, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Rizzo
authors.affiliation: Fondazione Don Carlo Gnocchi ONLUS, IRCCS S. Maria Nascente, Milan, Italy; Centre of Excellence for Nutrition (CEN), North-West University, Potchefstroom, South Africa.
authors.forename: Cristian
authors.initials: C
authors.lastname: Ricci
authors.affiliation: Esaote S.p.A., Florence, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: D'Onofrio
authors.affiliation: Esaote S.p.A., Florence, Italy.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Forzoni
authors.affiliation: Fondazione Don Carlo Gnocchi ONLUS, IRCCS S. Maria Nascente, Milan, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Cecconi
mesh_terms: D000293:Adolescent; D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology*; D018619:Echocardiography, Doppler, Pulsed / Q000379:methods; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007601:Jugular Veins / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D015656:Respiratory Mechanics / Q000502:physiology*; D055815:Young Adult
keywords: Blood flow velocity; Jugular vein; Pulsed Doppler ultrasonography; Ultrasound imaging