Hepatic blood flow during cardiopulmonary bypass.

摘要: OBJECTIVES To establish the effects of different modes cardiopulmonary bypass on hepatic blood flow, with aim increasing understanding hemodynamic factors that may lead to dysfunction in patients after bypass. The anatomical and physiologic characteristics are unique circulation also reviewed, together an account known specific liver several stimuli commonly present during DATA SOURCES entire world literature subjects clinical experimental bypass, extracorporeal circulation, gas tensions, hypothermia, hypotension, flow was searched via Index Medicus, up including 1991. EXTRACTION Data presented only from those studies employed sound or measurement technique. For investigations data for temperatures < 28 degrees C not included. Details one recent study dog by author highlighted, which relative pump rate, temperature, type perfusion (pulsatile nonpulsatile) presented; critically compared contrasted obtained earlier workers. SYNTHESIS Hepatic hemodynamics characterized a dual supply artery, actively controlled within liver, portal vein, principally regulated prehepatic resistance vessels. Portal modulate arterial through "hepatic buffer response." Hypotension caused hemorrhage causes decrease but is maintained autoregulation "buffer" response. Hypothermia (28 C) has little effect increase. During total better at rate 2.4 than 1.2 L/min/m2. Perfusion increase slight flow. Total preserved L/min/m2 pulsatile nonpulsatile flow; however, no significant difference noted between L/min/m2, particularly C. CONCLUSIONS high low rates. Hypothermic benefit although additional advantages usually gained use be partly lost when hypothermia combined rate.