title: The effect of arterial PCO2-variations on ocular and cerebral blood flow in the newborn piglet.
abstract: The response of ocular and cerebral blood flow to different arterial PCO2 levels was studied in ventilated paralyzed newborn piglets with the radionuclide-labeled microsphere method. The retina and the choroid have different blood flow responses to variations in arterial PCO2 levels. Retinal blood flow (ml/g/min) was increased during hypercarbia, from 0.26 +/- 0.03 at baseline to 0.51 +/- 0.07 (PaCO2 8.7 +/- 0.2 kPa) and 0.62 +/- 0.07 (PaCO2 11.0 +/- 0.2 kPa). However, no significant change was found in choroidal blood flow during hypercarbia. Cerebral blood flow was more responsive to PaCO2 than retinal blood flow, increasing from 0.71 +/- 0.03 at baseline to 2.25 +/- 0.25 (PaCO2 8.7 +/- 0.2) and 1.77 +/- 0.13 (PaCO2 11.0 +/- 0.2). Hypocarbia did not influence either retinal or choroidal blood flow.
authors.affiliation: Department of Pediatric Research, Rikshopitalet, University of Oslo, Norway.
authors.forename: T
authors.initials: T
authors.lastname: Stiris
authors.forename: J P
authors.initials: JP
authors.lastname: Odden
authors.forename: T W
authors.initials: TW
authors.lastname: Hansen
authors.forename: C
authors.initials: C
authors.lastname: Hall
authors.forename: D
authors.initials: D
authors.lastname: Bratlid
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000097:blood*; D002245:Carbon Dioxide / Q000097:blood*; D002560:Cerebrovascular Circulation; D005123:Eye / Q000098:blood supply*; D012160:Retina / Q000098:blood supply; D013552:Swine
chemical_list: D002245:Carbon Dioxide