Biomaterial Database

Effects of arterial and venous pressure alterations on transcapillary fluid exchange during raised tissue pressure. 1994

B Asgeirsson, and P O Grände

Department of Physiology and Biophysics, University of Lund, Sweden.

OBJECTIVE To assess local haemodynamic effects of raised tissue pressure per se and of arterial and venous pressure variations during raised tissue pressure, and to evaluate the vascular waterfall phenomenon. METHODS An isolated pump-perfused sympathectomised cat skeletal muscle enclosed in a plethysmograph. METHODS Hydrostatic capillary pressure (Pc), tissue volume alterations and blood flow were recorded at various arterial (PA) or venous (PV) pressure levels at a raised tissue pressure (Ptissue). Total vascular resistance (Rtot) and its three consecutive sections, arterial resistance (Rart), venular resistance (Rvenule), and venous outflow orifice resistance (Rorifice), were recorded. RESULTS Increase in Ptissue increased Pc due to a marked increase in Rorifice and unchanged Rart and, when Ptissue > PV, by about 90% of the Ptissue increase. During the raised Ptissue, a PA increase (95 to 115 mmHg) increased Pc (by 3.1 +/- 1.1 mmHg) causing fluid filtration, and a PA decrease (95 to 75 mmHg) decreased Pc (by 2.4 +/- 0.5 mmHg) causing fluid absorption. Rart was unchanged, indicating impaired autoregulation. Increased PV had no haemodynamic effects when PV < Ptissue due to a gradual decrease in Rorifice towards zero when PV reached Ptissue. At PV > Ptissue blood flow and Pc increased gradually, causing fluid filtration. CONCLUSIONS Tissue volume is increased by raised and decreased by lowered PA, the latter may be of use to decrease ICP in the injured brain. The results indicate that PEEP or head elevation will not influence ICP from the venous side if CVP < ICP. Finally, the "vascular waterfall phenomenon" was rejected as Rorifice is a normal variable fluid resistance.

UI	MeSH Term	Description	Entries
D007427	Intracranial Pressure	Pressure within the cranial cavity. It is influenced by brain mass, the circulatory system, CSF dynamics, and skull rigidity.	Intracerebral Pressure,Subarachnoid Pressure,Intracerebral Pressures,Intracranial Pressures,Pressure, Intracerebral,Pressure, Intracranial,Pressure, Subarachnoid,Pressures, Intracerebral,Pressures, Intracranial,Pressures, Subarachnoid,Subarachnoid Pressures
D008833	Microcirculation	The circulation of the BLOOD through the MICROVASCULAR NETWORK.	Microvascular Blood Flow,Microvascular Circulation,Blood Flow, Microvascular,Circulation, Microvascular,Flow, Microvascular Blood,Microvascular Blood Flows,Microvascular Circulations
D010991	Plethysmography	Recording of change in the size of a part as modified by the circulation in it.	Plethysmographies
D011559	Pseudotumor Cerebri	A condition marked by raised intracranial pressure and characterized clinically by HEADACHES; NAUSEA; PAPILLEDEMA, peripheral constriction of the visual fields, transient visual obscurations, and pulsatile TINNITUS. OBESITY is frequently associated with this condition, which primarily affects women between 20 and 44 years of age. Chronic PAPILLEDEMA may lead to optic nerve injury (see OPTIC NERVE DISEASES) and visual loss (see BLINDNESS).	Benign Intracranial Hypertension,Idiopathic Intracranial Hypertension,Intracranial Hypertension, Benign,Intracranial Hypertension, Idiopathic,Hypertension, Benign Intracranial,Hypertension, Idiopathic Intracranial
D001794	Blood Pressure	PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.	Systolic Pressure,Diastolic Pressure,Pulse Pressure,Pressure, Blood,Pressure, Diastolic,Pressure, Pulse,Pressure, Systolic,Pressures, Systolic
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D002496	Central Venous Pressure	The blood pressure in the central large VEINS of the body. It is distinguished from peripheral venous pressure which occurs in an extremity.	Venous Pressure, Central,Central Venous Pressures,Pressure, Central Venous,Pressures, Central Venous,Venous Pressures, Central
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013562	Sympathectomy	The removal or interruption of some part of the sympathetic nervous system for therapeutic or research purposes.	Denervation, Sympathetic,Sympathetic Denervation,Denervations, Sympathetic,Sympathectomies,Sympathetic Denervations
D014655	Vascular Resistance	The force that opposes the flow of BLOOD through a vascular bed. It is equal to the difference in BLOOD PRESSURE across the vascular bed divided by the CARDIAC OUTPUT.	Peripheral Resistance,Total Peripheral Resistance,Pulmonary Vascular Resistance,Systemic Vascular Resistance,Peripheral Resistance, Total,Resistance, Peripheral,Resistance, Pulmonary Vascular,Resistance, Systemic Vascular,Resistance, Total Peripheral,Resistance, Vascular,Vascular Resistance, Pulmonary,Vascular Resistance, Systemic