Hepatic haemodynamics

Walmsiey, B.H., Fleming, J.S., Ackery, D.M., Karran, S.J. Non-invasive assessment of absolute values of hepatic haemodynamics using radiocolloid scintigraphy. Nucl. Med. Com. 1987 8 613-621... 

The toxicity of rifamide has been studied [404,411] with almost consistently negative results. At very high doses, some species showed minor haemodynamic disturbances, whilst others showed minor renal or hepatic changes. No toxic effects have been observed in animals or humans at therapeutic doses. Pain may be encountered at the site of injection. 

In compensated cirrhosis, sodium retention can occur in the absence of vasodilatation and effective hypovolaemia. Sinusoidal portal hypertension can reduce renal blood flow even in the absence of haemodynamic changes in the systemic circulation, suggesting the existence of a hepatorenal reflex. Portal hypertension increases the hydrostatic pressure within the hepatic sinusoids and favours transudation of fluid into the peritoneal cavity. 

Cirrhosis Increased serum bile acid levels Two hypotheses 1) The result of haemodynamic alterations, shunts and reduced liver mass 2) Hepatic dysfunction at the cellular level May lead to pruritus in conditions of bile stasis... 

New England Journal of Medicine 345 41-52 Lee W M 1997 Hepatitis B virus infection. New England Journal of Medicine 337 1733-1745 Martin P-Y et al 1998 Nitric oxide as a mediator of haemodynamic abnormalities and sodium and water retention in cirrhosis. New England Journal of Medicine 339 533-541... 

From a haemodynamic point of view, the transjugular intrahepatic portosystemic stent shunt (TIPS) constitutes a portacaval side-to-side anastomosis in the form of a nonsurgical link between the portal vein and the hepatic vein. The TIPS can be closely compared with the portacaval interposition shunt, because the pressure reduction also depends on the shunt lumen. Stent placement leads to a permanent decrease in portal pressure, in 60—70% of cases, it was possible to achieve the desired reduction in pressure to almost 12 mm Hg. In addition, the splanchnic blood pool decreased, the cardiac output increased, the RAAS was deactivated and renal function improved. (70) (s.pp 259,314,329)... 

Fig. 7.4a,b. This patient was admitted in haemodynamic shock after a knife wound to the right hypochondrium. Emergency hepatic angiography revealed a segment 8 haemorrhage (a). As the patient had an unrecordable blood pressure at the time 700-900 pm PVA particles were injected selectively (b) with immediate improvement in haemodynamic status, the patient was discharged within 5 days of the procedure... 

Microbubbles are also ideal tracers because of the small injected volumes and this has been exploited in the liver to identify conditions characterised by arteriovenous shunting such as cirrhosis and metastases an early hepatic vein transit time indicates a haemodynamic abnormality (Blomley et al. 1998). The dynamics of the wash-in and wash-out phases following a bolus injection can be calculated and used to form functional images which are truly quantitative (Eckersley et al. 1998). 

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