title: Sufficient oxygen can be transported to resting skeletal muscle via arterialization of the vein: theoretical considerations in a rat model.
abstract: The blood supply to the lower limbs is often interrupted in patients suffering from arteriosclerosis obliterans (AO). In this condition, it is necessary to establish an oxygen supply via an alternative route. In the present theoretical study on rats, the possibility that adequate oxygen could be supplied through the venous system has been considered using simple calculations. The study was undertaken in the light of a report of a successful surgical approach in which the capillary bed is bypassed [1].The total lengths of the collecting venules and of the arcade venules per mm3 are reported to be 2.32 and 2.11 mm, respectively [2]. If these vessels were stretched out and connected to form a single, narrow venular tube, the total density would be 4.43 mm/mm(3). From the reciprocal of this value, the tissue cylinder surrounding the venule would have a radius of 268 µm. Taking an oxygen consumption rate for resting skeletal muscle of 0.16 ml/100g/min, and pO2 value of 40 mmHg, the one-dimensional diffusion equation gives a maximal diffusion distance of 328 µm. This is larger than the radius of the tissue cylinder surrounding the venular tube. A calculation for Krogh's tissue cylinder gives an oxygen partial pressure gradient of 54 mmHg between the inflow and the outflow terminals. These calculations suggest the oxygen content of the venous blood is adequate to supply sufficient oxygen to resting skeletal muscle. This is consistent with the successful outcome in patients with direct A-V anastomoses and implies that the capillary network is not essential for oxygen transport to resting skeletal muscle.
authors: Hokkaido University, Sapporo, Japan. tomkoyamajp@yahoo.co.jp
authors: Tomiyasu
authors: T
authors: Koyama
authors: Tomiyasu
authors: T
authors: Koyama
authors: Tadahiro
authors: T
authors: Sasajima
mesh_terms: D000818:Animals; D001158:Arteries / Q000502:physiology*; D023421:Models, Animal; D008962:Models, Theoretical; D018482:Muscle, Skeletal / Q000098:blood supply* / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption / Q000502:physiology; D051381:Rats; D014680:Veins / Q000502:physiology*
chemical_list: D010100:Oxygen