Change in plasma volume from a state of hyper-, normo- or hypovolemia with or without noradrenalin infusion in the rat

Pressure‐dependent changes in haematocrit and plasma volume during anaesthesia, a randomised clinical trial

“…1 Induction of anaesthesia has also been associated with haemodilution and increased plasma vol-ume. 3,4 This phenomenon has been explained by a norepinephrine-induced increase in hydrostatic capillary pressure via increases in arterial and venous pressures according to the two-pore theory of transcapillary fluid exchange. Theoretically, hypotension caused by anaesthesia induction, by e.g.…”

“…2 The mechanism behind this 'autotransfusion' caused by anaesthesia induction is not known. 3,4 According to the Starling principle, 5 changes in the arterial blood pressure may affect the balance between filtration and reabsorption of fluids, thus affecting circulating plasma volume, haematocrit and arterial oxygen content. propofol or barbiturates, may potentially decrease hydrostatic capillary pressure and thereby cause net transcapillary fluid absorption and a decrease in haematocrit.…”

“…It has previously been shown in experimental studies that norepinephrineinduced increases in arterial blood pressure induce a loss of plasma volume, which is greater under increased than under normal microvascular permeability. 3,4 This phenomenon has been explained by a norepinephrine-induced increase in hydrostatic capillary pressure via increases in arterial and venous pressures according to the two-pore theory of transcapillary fluid exchange. 3,4 According to the Starling principle, 5 changes in the arterial blood pressure may affect the balance between filtration and reabsorption of fluids, thus affecting circulating plasma volume, haematocrit and arterial oxygen content.…”

Norepinephrine causes a pressure‐dependent plasma volume decrease in clinical vasodilatory shock

“…The general inflammatory response after sepsis or cardiac surgery is accompanied by an increased capillary permeability, resulting in transcapillary fluid extravasation with resultant oedema and organ dysfunction as well as hypovolaemia 9–12 . Recent experimental studies have shown that a norepinephrine‐induced increase in blood pressure induces a loss of plasma volume, which is much greater under increased than under normal microvascular permeability 13,14 . This phenomenon has been explained by a norepinephrine‐induced increase in hydrostatic capillary pressure via increases in arterial and venous pressures according to the two‐pore theory of transcapillary fluid exchange 13,14 .…”

The spleen is required for 5-HT1Areceptor agonist-mediated increases in mean circulatory filling pressure during hemorrhagic shock in the rat

“…In normovolemic animals, veins contain up to 70% of total blood volume and serve as a blood reservoir due to their large capacitance (9,33). Splanchnic veins, liver, and spleen are important blood storage depots in some, but not all, mammalian species (10,32).…”