Regional Lung Blood Perfusion Measured With Laser Doppler Method During Body Position Change, Valsalva Manoeuvre and Cardiopulmonary Bypass

• Published in: Proceedings of the Latvian Academy of Sciences. Section B, Natural Sciences Vol. 62; no. 4-5; pp. 170 - 175
• Main Authors: Taivans, Immanuels, Strazda, Gunta, Porīte, Nora, Vanags, Indulis, Lejnieks, Juris, Lācis, Romāns, Strīķe, Eva
• Format: Journal Article
• Language: English
• Published: Riga Versita 01.01.2008; De Gruyter Poland
• Subjects: cardiac bypass; Laser Doppler technique; pulmonary vascular bed; Valsalva manoeuvre
• ISSN: 1407-009X; 2255-890X
• DOI: 10.2478/v10046-008-0026-x

Methodological approaches to investigate local regulatory mechanisms of lung blood supply in humans are restricted. We tried a new approach using laser Doppler technique. During bronchoscopy, an angled laser Doppler flow probe was introduced through a biopsy channel and wedged into small bronchus. Laser light penetrated the wall of small bronchus and was reflected from blood cells running through neighbouring capillaries. Regional blood perfusion changes were recorded during body position change from vertical to supine and back to vertical, while performing Valsalva maneuver and during cardiac bypass surgery. Body position change and Valsalva maneuver markedly influenced the blood perfusion signal. During cardiac bypass when lungs were supplied with blood only through bronchial arteries regional blood perfusion dropped substantially on average from 93 ± 42 to 7.3 ± 4.3 perfusion units. We conclude that blood perfusion measured with this method reflect mainly the pulmonary vascular bed and may be used for investigation of its local regulatory mechanisms. Plaušu asinsrites regulācijas mehānismi cilvēkam līdz šim maz pētīti, jo trūkst atbilstošu metožu. Pētījumā izmantota origināla pieeja, kas ļāva registrēt plaušu regionālo asinsriti, ieķīlējot lāzera Doplera leñķa zondi vienā no sīkajiem bronhiem bronhoskopijas laikā. Mērījumi tika veikti, cilvēkam atrodoties dažādās ķermeña pozās, kā arī veicot Valsalva manevru un sirds operācijās mākslīgās asinsrites laikā. Ķermeña pozu maiña un Valsalva manevrs būtiski ietekmē asins perfūziju plaušās. Mākslīgās asinsrites laikā plaušu asinsriti uztur tikai regionālā perfūzija bronhiālo artēriju līmenī, un tad perfūzija mazinās no 93 ± 42 līdz 7,3 ± 4,3 perfūzijas vienībām. Secināts, ka, izmantojot šādu metodiku, galvenokārt iegūst signālu no mazā asinsrites loka. Šādu metodiku var izmantot, lai pētītu lokālos asinsrites regulācijas mehānismus plaušās.