THE EFFECT OF HYPERCAPNIA ON ESTIMATED HEPATIC BLOOD FLOW, CIRCULATING SPLANCHNIC BLOOD VOLUME, AND HEPATIC SULFOBROMOPHTHALEIN CLEARANCE DURING GENERAL ANESTHESIA IN MAN*

Abstract Background Rapid fluid infusion resulting in increased hepatic blood flow may decrease the propofol plasma concentration (Cp) because propofol is a high hepatic extraction drug. The authors investigated the effects of rapid colloid and crystalloid infusions on the propofol Cp during target-controlled infusion. Methods Thirty-six patients were randomly assigned to 1 of 3 interventions (12 patients per group). At least 30 min after the start of propofol infusion, patients received either a 6% hydroxyethyl starch (HES) solution at 24 ml·kg−1·h−1 or acetated Ringer’s solution at 24 or 2 ml·kg−1·h−1 during the first 20 min. In all groups, acetated Ringer’s solution was infused at 2 ml·kg−1·h−1 during the next 20 min. The propofol Cp was measured every 2.5 min as the primary outcome. Cardiac output, blood volume, and indocyanine green disappearance rate were determined using a pulse dye densitogram analyzer before and after the start of fluid administration. Effective hepatic blood flow was calculated as the blood volume multiplied by the indocyanine green disappearance rate. Results The rapid HES infusion significantly decreased the propofol Cp by 22 to 37%, compared to the Cp at 0 min, whereas the rapid or maintenance infusion of acetate Ringer’s solution did not decrease the propofol Cp. Rapid HES infusion, but not acetate Ringer’s solution infusion, increased the effective hepatic blood flow. Conclusions Rapid HES infusion increased the effective hepatic blood flow, resulting in a decreased propofol Cp during target-controlled infusion. Rapid HES infusion should be used cautiously as it may decrease the depth of anesthesia.

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General anesthesia and hepatic circulation

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y87-276 ◽

1987 ◽

Vol 65 (8) ◽

pp. 1762-1779 ◽

Cited By ~ 94

Author(s):

Simon Gelman

Keyword(s):

Blood Flow ◽

General Anesthesia ◽

Surgical Procedures ◽

Hepatic Blood Flow ◽

Portal Blood Flow ◽

Arterial Blood Flow ◽

Hepatic Circulation ◽

Arterial Blood ◽

Total Hepatic Blood Flow ◽

Circulatory Disturbances

This article describes hepatic circulatory disturbances associated with anesthesia and surgical intervention. The material is presented in three parts: part 1 describes the effects of general anesthetics on the hepatic circulation; part 2 deals with different factors related to surgical procedures and anesthesia; and part 3 analyzes the role of hepatic circulatory disturbances and hepatic oxygen deprivation in anesthesia-induced hepatotoxicity. The analysis of available data suggests that general anesthesia affects the splanchnic and hepatic circulation in various directions and to different degrees. The majority of anesthetics decreases portal blood flow in association with a decrease in cardiac output. However, hepatic arterial blood flow can be preserved, decreased, or increased. The increase in hepatic arterial blood flow, when it occurs, is usually not enough to compensate for a decrease in portal blood flow and therefore total hepatic blood flow is usually decreased during anesthesia. This decrease in total hepatic blood flow-has certain pharmacokinetic implications, namely a decrease in clearance of endogenous and exogenous substances with a high hepatic extraction ratio. On the other hand, a reduction in the hepatic oxygen supply might play a certain role in liver dysfunction occurring perioperatively. Surgical procedures–preparations combined with anesthesia have a very complex effect on the splanchnic and hepatic circulation. Within this complex, the surgical procedure–preparation plays the main role in developing circulatory disturbances, while anesthesia plays only a modifying role. Hepatic oxygen deprivation may play an important role in anesthesia-induced hepatotoxicity in different experimental models.

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General Anesthesia with Sevoflurane Decreases Myocardial Blood Volume and Hyperemic Blood Flow in Healthy Humans

Anesthesia & Analgesia ◽

10.1213/ane.0b013e31827e4e41 ◽

2013 ◽

Vol 116 (4) ◽

pp. 767-774 ◽

Cited By ~ 9

Author(s):

Carolien S. E. Bulte ◽

Jeroen Slikkerveer ◽

Otto Kamp ◽

Martijn W. Heymans ◽

Stephan A. Loer ◽

...

Keyword(s):

Blood Flow ◽

General Anesthesia ◽

Blood Volume ◽

Healthy Humans ◽

Myocardial Blood Volume

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The Effects of Thoracic Epidural Anesthesia on Hepatic Blood Flow in Patients Under General Anesthesia

Anesthesia & Analgesia ◽

10.1213/ane.0b013e3181966e6f ◽

2009 ◽

Vol 108 (4) ◽

pp. 1331-1337 ◽

Cited By ~ 24

Author(s):

Rainer Meierhenrich ◽

Florian Wagner ◽

Wolfram Schütz ◽

Michael Rockemann ◽

Peter Steffen ◽

...

Keyword(s):

Blood Flow ◽

General Anesthesia ◽

Hepatic Blood Flow ◽

Epidural Anesthesia ◽

Thoracic Epidural Anesthesia ◽

Thoracic Epidural

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Response of Estimated Hepatic Blood Flow to Graded Hemorrhage and the Infusion of Levarterenol

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1958.195.2.469 ◽

1958 ◽

Vol 195 (2) ◽

pp. 469-472 ◽

Cited By ~ 6

Author(s):

J. P. Gilmore

Keyword(s):

Blood Flow ◽

Oxygen Consumption ◽

Blood Volume ◽

Hepatic Blood Flow ◽

Percentage Reduction ◽

Splanchnic Oxygen ◽

Oxygen Difference

Levarterenol did not significantly affect the estimated hepatic blood flow, arterial-hepatic venous oxygen difference, or splanchnic oxygen consumption of the dog during graded hemorrhage. During the later stage of hemorrhage hepatic blood flow tended to spontaneously increase so that the percentage reduction in hepatic blood flow was less than the percentage reduction in blood volume.

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Effects of positive end-expiratory pressure on hepatic blood flow and performance

Journal of Applied Physiology ◽

10.1152/jappl.1987.62.4.1377 ◽

1987 ◽

Vol 62 (4) ◽

pp. 1377-1383 ◽

Cited By ~ 80

Author(s):

G. M. Matuschak ◽

M. R. Pinsky ◽

R. M. Rogers

Keyword(s):

Blood Flow ◽

Blood Volume ◽

Hepatic Blood Flow ◽

Positive Pressure Ventilation ◽

Hepatic Function ◽

Intermittent Positive Pressure Ventilation ◽

Positive Pressure ◽

Intravascular Volume ◽

Positive End Expiratory Pressure ◽

Group I

Positive end-expiratory pressure (PEEP) may impair extrapulmonary organ function. However, the effects of PEEP on the liver are unclear. We tested the hypothesis that at a constant cardiac output (CO), PEEP does not induce changes in hepatic blood flow (QL) and parenchymal performance. In splenectomized, close-chested canine preparations (group I, n = 6), QL was derived as hepatic outflow using electromagnetic flow probes (QLemf), and hepatic performance was defined by extraction and clearance of indocyanine green (ICG). In a noninvasive model (group II, n = 7), the effects of PEEP on hepatic performance alone were similarly analyzed. Measurements were taken during intermittent positive-pressure ventilation (IPPV1), after addition of 10 cmH2O PEEP to IPPV (PEEP1), during continued PEEP but after return of CO to IPPV1 levels by intravascular volume infusions (PEEP2), and after removal of both PEEP and excess blood volume (IPPV2). Phasic inspiratory decreases in QLemf present during positive-pressure ventilation were not increased during either PEEP1 or PEEP2. Mean QLemf decreased proportionately with CO during PEEP1 (P less than 0.05), but was restored to IPPV1 levels in a parallel fashion with CO during PEEP2. The ICG pharmacokinetic responses to PEEP were complex, with differential effects on extraction and clearance. Despite this, hepatic performance was not imparied in either group. we conclude that global QL reductions during PEEP are proportional to PEEP-induced decreases in CO and are preventable by returning CO to pre-PEEP levels by intravascular volume infusions. However, covarying changes in blood volume and hepatic outflow resistance may independently modulate hepatic function.

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The influence of thoracic epidural anesthesia on liver hemodynamics in patients under general anesthesia

Medicina ◽

10.3390/medicina46070067 ◽

2010 ◽

Vol 46 (7) ◽

pp. 465 ◽

Cited By ~ 5

Author(s):

Darius Trepenaitis ◽

Juozas Pundzius ◽

Andrius Macas

Keyword(s):

Blood Pressure ◽

Blood Flow ◽

General Anesthesia ◽

Hepatic Blood Flow ◽

Epidural Anesthesia ◽

Mean Arterial Blood Pressure ◽

Thoracic Epidural Anesthesia ◽

Control Group ◽

Thoracic Epidural ◽

Arterial Blood

Background and objective. Hepatic hypoperfusion is regarded as an important factor in the pathophysiology of perioperative liver injury. Although thoracic epidural anesthesia is a widely used technique, limited data are available about the effects on hepatic blood flow with blockade restricted to thoracic segments in humans. The main objective of the present study was to investigate the effects of thoracic epidural anesthesia on hepatic blood flow under general anesthesia in humans. Material and methods. In 40 patients under general anesthesia, we assessed hepatic blood flow using plasma disappearance rate of indocyanine green (PDRICG) as a simple noninvasive method before and after induction of thoracic epidural anesthesia. The epidural catheter was inserted at the Th7/8 or Th8/9, and 1% lidocaine at a mean (range) dose of 8 (6–10) mL was injected. Ephedrine bolus was given to patients who demonstrated a decrease in mean arterial blood pressure below 60 mm Hg after induction of thoracic epidural anesthesia (TEA-E group). Other patients did not receive any catecholamines during the study period (TEA group). Ten patients who did not undergo TEA served as controls (control group). Results. In 7 patients, administration of ephedrine was necessary to avoid a decrease in mean arterial blood pressure below 60 mm Hg. Thus, the TEA-E group consisted of 7 patients and TEA group of 33. In the TEA group, thoracic epidural anesthesia was associated with a mean 2.3% min–1 decrease in PDRICG (P<0.05). In the TEA-E group, all seven patients showed a 2.2% min–1decrease in PDRICG (P<0.05). Patients in the control group showed a mean 1.1% min–1 increase in PDRICG (P<0.05). In contrast to hepatic blood flow, cardiac output was not affected by thoracic epidural anesthesia. Conclusions. In humans, thoracic epidural anesthesia is associated with a decrease in hepatic blood flow. Thoracic epidural anesthesia combined with ephedrine bolus was found to result in further decrease in hepatic blood flow.

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