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1.
J Clin Endocrinol Metab ; 101(12): 5044-5052, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27648961

RESUMO

BACKGROUND: Plasma acylcarnitine levels are elevated by physiological conditions such as fasting and exercise but also in states of insulin resistance and obesity. AIM: To elucidate the contribution of liver and skeletal muscle to plasma acylcarnitines in the fasting state and during exercise in humans. METHODS: In 2 independent studies, young healthy males were fasted overnight and performed an acute bout of exercise to investigate either acylcarnitines in skeletal muscle biopsies and arterial-to-venous plasma differences over the exercising and resting leg (n = 9) or the flux over the hepato-splanchnic bed (n = 10). RESULTS: In the fasting state, a pronounced release of C2- and C3-carnitines from the hepato-splanchnic bed and an uptake of free carnitine by the legs were detected. Exercise further increased the release of C3-carnitine from the hepato-splanchnic bed and the uptake of free carnitine in the exercising leg. In plasma and in the exercising muscle, exercise induced an increase of most acylcarnitines followed by a rapid decline to preexercise values during recovery. In contrast, free carnitine was decreased in the exercising muscle and quickly restored thereafter. C8-, C10-, C10:1-, C12-, and C12:1-carnitines were released from the exercising leg and simultaneously; C6, C8, C10, C10:1, C14, and C16:1 were taken up by the hepato-splanchnic. CONCLUSION: These data provide novel insight to the organo-specific release/uptake of acylcarnitines. The liver is a major contributor to systemic short chain acylcarnitines, whereas the muscle tissue releases mostly medium chain acylcarnitines during exercise, indicating that other tissues are contributing to the systemic increase in long chain acylcarnitines.


Assuntos
Carnitina/análogos & derivados , Exercício Físico/fisiologia , Jejum/metabolismo , Fígado/metabolismo , Músculo Esquelético/metabolismo , Adulto , Carnitina/sangue , Carnitina/metabolismo , Jejum/sangue , Humanos , Perna (Membro) , Masculino , Adulto Jovem
2.
J Appl Physiol (1985) ; 92(4): 1677-83, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11896037

RESUMO

We evaluated whether the increase in blood lactate with intense exercise is influenced by a low hepatosplanchnic blood flow as assessed by indocyanine green dye elimination and blood sampling from an artery and the hepatic vein in eight men. The hepatosplanchnic blood flow decreased from a resting value of 1.6 +/- 0.1 to 0.7 +/- 0.1 (SE) l/min during exercise. Yet the hepatosplanchnic O2 uptake increased from 67 +/- 3 to 93 +/- 13 ml/min, and the output of glucose increased from 1.1 +/- 0.1 to 2.1 +/- 0.3 mmol/min (P < 0.05). Even at the lowest hepatosplanchnic venous hemoglobin O2 saturation during exercise of 6%, the average concentration of glucose in arterial blood was maintained close to the resting level (5.2 +/- 0.2 vs. 5.5 +/- 0.2 mmol/l), whereas the difference between arterial and hepatic venous blood glucose increased to a maximum of 22 mmol/l. In arterial blood, the concentration of lactate increased from 1.1 +/- 0.2 to 6.0 +/- 1.0 mmol/l, and the hepatosplanchnic uptake of lactate was elevated from 0.4 +/- 0.06 to 1.0 +/- 0.05 mmol/min during exercise (P < 0.05). However, when the hepatosplanchnic venous hemoglobin O2 saturation became low, the arterial and hepatosplanchnic venous blood lactate difference approached zero. Even with a marked reduction in its blood flow, exercise did not challenge the ability of the liver to maintain blood glucose homeostasis. However, it appeared that the contribution of the Cori cycle decreased, and the accumulation of lactate in blood became influenced by the reduced hepatosplanchnic blood flow.


Assuntos
Ácido Láctico/sangue , Circulação Hepática/fisiologia , Fígado/metabolismo , Esforço Físico/fisiologia , Circulação Esplâncnica/fisiologia , Adulto , Glicemia/metabolismo , Dióxido de Carbono/sangue , Catecolaminas/sangue , Artéria Hepática/fisiologia , Veias Hepáticas/fisiologia , Humanos , Fígado/irrigação sanguínea , Masculino , Oxigênio/sangue , Consumo de Oxigênio/fisiologia , Pressão Parcial
3.
Liver Transpl ; 7(11): 964-70, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11699032

RESUMO

Patients with fulminant hepatic failure (FHF) frequently develop cerebral edema and intracranial hypertension. The aim of this study was to evaluate circulating S-100b and neuron-specific enolase (NSE) levels as markers of neurological outcome in patients with FHF. In a subgroup of patients, the cerebral flux of S-100b and NSE was measured. We included 35 patients with FHF, 6 patients with acute on chronic liver disease (AOCLD), 13 patients with cirrhosis of the liver without hepatic encephalopathy, and 8 healthy subjects. Blood samples were obtained from catheters placed in the radial artery and internal jugular bulb. The net cerebral flux of S-100b and NSE was measured, and the effect of short-term hyperventilation, as well as the effect of high-volume plasmapheresis, on circulating levels of these two biomarkers was determined. Blood levels of S-100b were greater in patients with FHF and AOCLD than patients with cirrhosis and healthy subjects (median, 0.39 microg/L; range, 0.02 to 10.31 microg/L; and 1.11 microg/L; range, 0.19 to 4.84 microg/L v 0.05 microg/L; range, 0.02 to 0.27 microg/L; and 0.09 microg/L; range, 0.02 to 0.15 microg/L, respectively; P <.05, ANOVA). Among patients with FHF, blood levels of NSE tended to be greater in patients who subsequently developed cerebral herniation than in survivors (median, 10.5 microg/L; range, 5.2 to 15.9 microg/L v 5.1 microg/L; range, 2.8 to 12 microg/L; P =.05). There was no net cerebral flux of S-100b or NSE. Short-term hyperventilation had no effect on any of these measures, whereas high-volume plasmapheresis reduced circulating S-100b levels from 0.45 microg/L (range, 0.19 to 10.31 microg/L) to 0.42 microg/L (range, 0.11 to 6.35 microg/L; P =.01). In conclusion, blood levels of S-100b were elevated in almost all patients with FHF and AOCLD, but were unrelated to survival. Conversely, NSE showed a clear tendency toward greater circulating levels in patients with FHF who subsequently developed cerebral herniation than in survivors. This finding encourages further evaluation of NSE as a marker of neurological outcome in FHF.


Assuntos
Circulação Cerebrovascular , Falência Hepática/sangue , Fosfopiruvato Hidratase/sangue , Proteínas S100/sangue , Doença Aguda , Adulto , Doença Crônica , Encefalocele/sangue , Encefalocele/etiologia , Feminino , Humanos , Cirrose Hepática/sangue , Hepatopatias/sangue , Falência Hepática/terapia , Masculino , Pessoa de Meia-Idade , Fatores de Crescimento Neural , Plasmaferese , Valores de Referência , Respiração Artificial/métodos , Subunidade beta da Proteína Ligante de Cálcio S100
4.
Scand J Gastroenterol ; 36(9): 998-1003, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11521994

RESUMO

BACKGROUND: A low serum level (< 100 mg/L) of the actin-scavenger Gc-globulin is a prognostic marker of non-survival in fulminant hepatic failure (FHF). It is unknown whether decreased production or increased consumption (or both) is responsible for the low Gc-globulin levels. METHODS: Ten patients with FHF and four patients with acute or chronic liver disease (AOCLD) with hepatic encephalopathy (HE) grades II-IV were included. Eight patients with cirrhosis (chronic liver disease, CLD) without HE served as controls. Total, free, and actin-bound Gc-globulin were measured in samples from an artery, a central vein, and a hepatic vein. In 12 patients (9 FHF, 3 AOCLD), concentrations were measured before and after high volume plasmapheresis (HVP). RESULTS: Total Gc-globulin was reduced to 21%, 40%, and 43% of the normal level in the FHF, AOCLD, and CLD groups, respectively, whereas bound Gc-globulin was within normal range in all patients. The Gc:actin complex ratio was increased 3.8, 2.5, and 1.9-fold compared with normal levels. Total, free, and bound serum Gc-globulin levels did not differ among arterial, systemic venous, or hepatic venous blood. Total Gc-globulin rose to >100 mg/L in all patients after HVP, whereas bound Gc-globulin remained unchanged. The Gc-globulin production rate in FHF and AOCLD patients was increased to 4.1 +/- 1.3 mg/min compared to literature values of 0.6 mg/min in healthy individuals. The estimated half-life of total Gc-globulin was shorter in the patients compared to healthy individuals (127 +/- 56 min and 870 min, respectively). CONCLUSIONS: Gc-globulin levels were reduced in patients with FHF and AOCLD because a 7-fold increase of Gc-globulin production rate could not compensate for the accelerated clearance. Bound Gc-globulin was maintained within normal levels in all circumstances studied, indicating a possible regulatory role of this parameter in the clearance of actin.


Assuntos
Encefalopatia Hepática/metabolismo , Cirrose Hepática/metabolismo , Falência Hepática/metabolismo , Proteína de Ligação a Vitamina D/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Meia-Vida , Encefalopatia Hepática/sangue , Humanos , Cirrose Hepática/sangue , Falência Hepática/sangue , Masculino , Proteína de Ligação a Vitamina D/sangue
5.
Am J Gastroenterol ; 96(4): 1217-23, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11316173

RESUMO

OBJECTIVE: In acute liver failure (ALF), urea production is severely impaired, and detoxification of ammonia by glutamine synthesis plays an important protective role. The aim of this study was to examine the effects of therapeutic high-volume plasmapheresis (HVP) on arterial concentrations and splanchnic exchange rates of ammonia, urea, and amino acids-in particular, glutamine. METHODS: A quantity of 8 L of plasma was exchanged over the course of 7 h in 11 patients with ALF after development of hepatic encephalopathy grade III-IV. Splanchnic exchange rates of ammonia, urea, and amino acids were measured by use of liver vein catheterization. RESULTS: HVP removed ammonia and glutamine at a rate of 1 micromol/min and 27 micromol/min, respectively. Arterial ammonia decreased from 160 +/- 65 to 114 +/- 50 micromol/L (p < 0.001). In contrast, arterial glutamine was only minimally changed from 1791 +/- 1655 to 1764 +/- 1875 micromol/L (NS). This implied that the rate of systemic glutamine synthesis was increased by 27 micromol/min. Splanchnic exchange rates (before vs after HVP) were as follows: for ammonia, -93 +/- 101 versus -70 +/- 80 micromol/min (NS); urea-nitrogen, 0.08 +/- 1.64 versus -0.31 +/- 0.45 mmol/min (NS); alanine, -73 +/- 151 versus 12 +/- 83 micromol/min (p < 0.05); and glutamine: 132 +/- 246 versus 186 +/- 285 micromol/min (NS), with negative values denoting release. CONCLUSIONS: Arterial ammonia decreased during HVP in patients with ALF. The data suggest that this effect of HVP could be explained by increased hepatic urea synthesis and possibly by increased glutamine synthesis in muscle tissue.


Assuntos
Aminoácidos/metabolismo , Amônia/metabolismo , Falência Hepática Aguda/metabolismo , Plasmaferese , Ureia/metabolismo , Adulto , Feminino , Humanos , Masculino
6.
J Hepatol ; 33(6): 941-8, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11131456

RESUMO

BACKGROUND/AIMS: This study aimed to characterize the exchange of fuel substrates in the splanchnic circulation in acute liver failure. METHODS: Liver vein catheterization was used in 22 patients with acute liver failure after development of hepatic encephalopathy grade III-IV Healthy controls, patients with cirrhosis and patients with acute on chronic liver disease were also studied. RESULTS: In acute liver failure there was splanchnic removal of glucose (0.21+/-0.44 mmol/min), release of lactate (0.34+/-0.37 mmol/min), pyruvate (0.08+/-0.06 mmol/min) and ketone bodies (0.04+/-0.02 mmol/min), while extraction of amino acids and free fatty acids was insignificant. In the acute liver failure group, a normal hepatic venous oxygen saturation (0.69+/-0.12) and normal pyruvate/lactate ratio suggested absence of hypoxia even though the acetoacetate/beta-hydroxybutyrate ratio was decreased. Only in the acute liver failure group did the measured splanchnic oxygen content difference exceed what could be accounted for even by hypothesizing complete oxidation of all extracted blood-borne fuel substrates; oxidation of endogenous substrates may be quantitatively important in this condition. CONCLUSION: Acute liver failure was associated with a state of accelerated glycolysis in the splanchnic region, leading to release of lactate in the absence of splanchnic hypoxia.


Assuntos
Injúria Renal Aguda/metabolismo , Circulação Esplâncnica , Ácido 3-Hidroxibutírico/sangue , Acetoacetatos/sangue , Adulto , Glicemia/análise , Feminino , Encefalopatia Hepática/sangue , Veias Hepáticas , Humanos , Corpos Cetônicos/sangue , Ácido Láctico/sangue , Cirrose Hepática/sangue , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Piruvatos/sangue , Valores de Referência
7.
Gastroenterology ; 118(6): 1131-9, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10833488

RESUMO

BACKGROUND & AIMS: In patients with acute liver failure, hyperammonemia is associated with cerebral herniation. We examined the splanchnic and leg exchange of amino acids, urea, and ammonia in such patients. METHODS: Bedside liver vein catheterization was used in 22 patients after development of hepatic encephalopathy grades III-IV. Femoral venous blood was sampled in 7 of these patients. RESULTS: Arterial amino acid concentration (8.1 +/- 4.1 mmol/L) was increased 4-fold above normal. Glutamine (2.4 +/- 1.8 mmol/L) and alanine (0.57 +/- 0.35 mmol/L) were by far the predominant amino acids exchanged in the splanchnic and leg circulation. In the splanchnic circulation, there was a net uptake of glutamine (241 +/- 353 micromol/min) and ammonia and alanine were released in an almost 1:1 stoichiometry (r(2) = 0.47; P < 0.001). In the leg, ammonia and alanine were removed and glutamine released. The leg ammonia concentration difference was correlated to that of glutamine (r(2) = 0.80; P = 0.008) and alanine (r(2) = 0.67; P = 0.03). CONCLUSIONS: Splanchnic metabolism of glutamine in combination with decreased hepatic function was responsible for the splanchnic release of ammonia and alanine. These processes were reversed in skeletal muscle. Stimulation of skeletal muscle metabolism of ammonia could be a important target for future treatment of patients with acute liver failure.


Assuntos
Aminoácidos/sangue , Amônia/sangue , Falência Hepática Aguda/metabolismo , Falência Hepática Aguda/fisiopatologia , Circulação Esplâncnica/fisiologia , Adulto , Alanina/sangue , Nitrogênio da Ureia Sanguínea , Citrulina/sangue , Feminino , Artéria Femoral/fisiologia , Veia Femoral/fisiologia , Fibrose/metabolismo , Fibrose/fisiopatologia , Glutamina/sangue , Humanos , Perna (Membro)/irrigação sanguínea , Falência Hepática Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prolina/sangue , Ureia/sangue
8.
J Hepatol ; 32(3): 481-7, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10735619

RESUMO

BACKGROUND/AIMS: In acute liver failure the liver has to regenerate, which may increase the consumption of essential fatty acids. Nutritional support consists mainly of infusion of glucose. It is therefore possible that essential fatty acid deficiency may develop in such patients. METHODS: Plasma phospholipid composition was studied in healthy controls (n=11), in patients with acute liver failure, (n=10), in patients with stable cirrhosis (n=7), and in patients with acute on chronic liver disease with hepatic encephalopathy (n=6). The influence of 2 days of fat-free diet followed by infusion of glucose was studied in five healthy controls. RESULTS: The ratio between the sums of nonessential/ essential fatty acids, (n-7+n-9)/(n-3+n-6), was higher in patients with acute liver failure (0.73+/-0.17) compared to healthy controls (0.35+/-0.06, p<0.001). The ratio was also higher in patients with acute on chronic liver disease (1.11+/-0.39) compared to patients with cirrhosis (0.61+/-0.18, p<0.01). These differences were mainly due to low levels of linoleic acid and high levels of oleic acid in the patients with acute liver failure and acute on chronic liver disease. Two days of fat-free diet followed by infusion of glucose did not change this ratio (0.40+/-0.04 vs. 0.47+/-0.05, NS) in healthy controls. The essential fatty acid deficiency indicator eicosatrienoic acid was detectable in 2 out of 11 controls, in 5/10 with acute liver failure, in 7/7 with cirrhosis, and in 6/7 with acute on chronic liver disease. CONCLUSION: Acute severe deterioration of liver function was associated with changes in the fatty acid composition of plasma phospholipids suggestive of essential fatty acid deficiency.


Assuntos
Ácidos Graxos/sangue , Encefalopatia Hepática/sangue , Hepatopatias/sangue , Fosfolipídeos/sangue , Doença Aguda , Adulto , Doença Crônica , Gorduras na Dieta/administração & dosagem , Feminino , Glucose/farmacologia , Humanos , Ácido Linoleico/sangue , Cirrose Hepática/sangue , Falência Hepática/sangue , Masculino , Pessoa de Meia-Idade , Ácido Oleico/sangue , Valores de Referência
9.
Scand J Gastroenterol ; 34(9): 921-7, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10522613

RESUMO

BACKGROUND: Arterial hypotension occurs frequently in patients with acute liver failure (ALF). Treatment with epinephrine and norepinephrine in patients with ALF has been associated with a decrease in whole-body (systemic) oxygen consumption. We aimed to investigate the effect of increasing blood pressure with dopamine on whole-body (systemic), splanchnic, and lower extremity hemodynamics and oxygen consumption in patients with acute liver failure and hepatic encephalopathy grade III or IV. METHODS: In seven patients with ALF cardiac output (CO) was measured with the thermodilution technique, and hepatic blood flow (HBF) was estimated with infusion of sorbitol as test compound, liver vein catheterization, and calculations on the basis of Fick's principle. Lower-extremity blood flow was measured with strain-gauge plethysmography. RESULTS: During infusion of dopamine (5 +/- 2 microg kg(-1) min(-1)) mean arterial pressure (MAP) increased from 68 +/- 5 to 85 +/- 8 mmHg. CO increased from 6.8 +/- 0.8 to 9.0 +/- 2.4 l/min (P < 0.05), systemic oxygen delivery from 45 +/- 7 to 63 +/- 19 mmol/min (P < 0.05), systemic oxygen consumption from 10.2 +/- 2.0 to 11.5 +/- 3.3 mmol/min (NS). HBF increased from 2.2 +/- 0.7 to 2.7 +/- 1.0 l/ min (P < 0.05), splanchnic oxygen delivery from 14.4 +/- 5.3 to 18.5 +/- 7.2 mmol/min (P < 0.01), and splanchnic oxygen consumption decreased from 3.9 +/- 1.1 to 2.9 +/- 0.6 mmol/min (P < 0.05). No significant changes in lower extremity flow and oxygenation variables were found. CONCLUSIONS: The use of dopamine in patients with ALF to increase MAP was associated with increases in systemic and splanchnic oxygen delivery. A concomitant decrease in splanchnic oxygen consumption was observed.


Assuntos
Dopamina/farmacologia , Hemodinâmica/efeitos dos fármacos , Encefalopatia Hepática/tratamento farmacológico , Encefalopatia Hepática/fisiopatologia , Hipotensão/tratamento farmacológico , Hipotensão/etiologia , Doença Aguda , Adulto , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Dopamina/uso terapêutico , Feminino , Humanos , Perna (Membro)/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/efeitos dos fármacos , Circulação Esplâncnica/efeitos dos fármacos , Estatísticas não Paramétricas
10.
Hepatology ; 29(3): 648-53, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10051463

RESUMO

Cerebral edema leading to cerebral herniation (CH) is a common cause of death in acute liver failure (ALF). Animal studies have related ammonia with this complication. During liver failure, hepatic ammonia removal can be expected to determine the arterial ammonia level. In patients with ALF, we examined the hypotheses that high arterial ammonia is related to later death by CH, and that impaired removal in the hepatic circulation is related to high arterial ammonia. Twenty-two patients with ALF were studied retrospectively. In addition, prospective studies with liver vein catheterization were performed after development of hepatic encephalopathy (HE) in 22 patients with ALF and 9 with acute on chronic liver disease (AOCLD). Cerebral arterial-venous ammonia difference was studied in 13 patients with ALF. In all patients with ALF (n = 44), those who developed CH (n = 14) had higher arterial plasma ammonia than the non-CH (n = 30) patients (230 +/- 58 vs. 118 +/- 48 micromol/L; P <. 001). In contrast, galactose elimination capacity, bilirubin, creatinine, and prothrombin time were not different (NS). Cerebral arterial-venous differences increased with increasing arterial ammonia (P <.001). Arterial plasma ammonia was lower than hepatic venous in ALF (148 +/- 73 vs. 203 +/- 108 micromol/L; P <.001). In contrast, arterial plasma ammonia was higher than hepatic venous in patients with AOCLD (91 +/- 26 vs. 66 +/- 18 micromol/L; P <.05). Net ammonia release from the hepatic-splanchnic region was 6.5 +/- 6. 4 mmol/h in ALF, and arterial ammonia increased with increasing release. In contrast, there was a net hepatic-splanchnic removal of ammonia (2.8 +/- 3.3 mmol/h) in patients with AOCLD. We interpret these data that in ALF in humans, vast amounts of ammonia escape hepatic metabolism, leading to high arterial ammonia concentrations, which in turn is associated with increased cerebral ammonia uptake and CH.


Assuntos
Amônia/sangue , Encefalocele/etiologia , Falência Hepática/sangue , Falência Hepática/complicações , Doença Aguda , Adulto , Artérias , Encefalocele/mortalidade , Feminino , Encefalopatia Hepática/sangue , Encefalopatia Hepática/fisiopatologia , Humanos , Circulação Hepática/fisiologia , Falência Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Estudos Prospectivos , Estudos Retrospectivos , Veias
11.
Hepatology ; 29(2): 347-55, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9918909

RESUMO

Liver failure represents a major therapeutic challenge, and yet basic pathophysiological questions about hepatic perfusion and oxygenation in this condition have been poorly investigated. In this study, hepatic blood flow (HBF) and splanchnic oxygen delivery (DO2, sp) and oxygen consumption (VO2,sp) were assessed in patients with liver failure defined as hepatic encephalopathy grade II or more. Measurements were repeated after high-volume plasmapheresis (HVP) with exchange of 8 to 10 L of plasma. HBF was estimated by use of constant infusion of D-sorbitol and calculated according to Fick's principle from peripheral artery and hepatic vein concentrations. In 14 patients with acute liver failure (ALF), HBF (1.78 +/- 0.78 L/min) and VO2,sp (3.9 +/- 0.9 mmol/min) were higher than in 11 patients without liver disease (1.07 +/- 0.19 L/min, P <.01) and (2.3 +/- 0.7 mmol/min, P <.001). In 9 patients with acute on chronic liver disease (AOCLD), HBF (1.96 +/- 1.19 L/min) and VO2,sp (3.9 +/- 2.3 mmol/min) were higher than in 18 patients with stable cirrhosis (1.00 +/- 0.36 L/min, P <.005; and 2.0 +/- 0.6 mmol/min, P <.005). During HVP, HBF increased from 1.67 +/- 0.72 to 2.07 +/- 1.11 L/min (n=11) in ALF, and from 1.89 +/- 1.32 to 2.34 +/- 1.54 L/min (n=7) in AOCLD, P <.05 in both cases. In patients with ALF, cardiac output (thermodilution) was unchanged (6.7 +/- 2.5 vs. 6.6 +/- 2.2 L/min, NS) during HVP. Blood flow was redirected to the liver as the systemic vascular resistance index increased (1,587 +/- 650 vs. 2, 020 +/- 806 Dyne. s. cm-5. m2, P <.01) whereas splanchnic vascular resistance was unchanged. In AOCLD, neither systemic nor splanchnic vascular resistance was affected by HVP, but as cardiac output increased from 9.1 +/- 2.8 to 10.1 +/- 2.9 L/min (P <.01) more blood was directed to the splanchnic region. In all liver failure patients treated with HVP (n=18), DO2,sp increased by 15% (P <.05) whereas VO2,sp was unchanged. Endothelin-1 (ET-1) and ET-3 were determined before and after HVP. Changes of ET-1 were positively correlated with changes in HBF (P <.005) and VO2,sp (P <.05), indicating a role for ET-1 in splanchnic circulation and oxygenation. ET-3 was negatively correlated with systemic vascular resistance index before HVP (P <.05) but changes during HVP did not correlate. Our data suggest that liver failure is associated with increased HBF and VO2, sp. HVP further increased HBF and DO2,sp but VO2,sp was unchanged, indicating that splanchnic hypoxia was not present.


Assuntos
Circulação Hepática , Falência Hepática/fisiopatologia , Falência Hepática/terapia , Consumo de Oxigênio , Plasmaferese , Circulação Esplâncnica , Doença Aguda , Adulto , Velocidade do Fluxo Sanguíneo , Doença Crônica , Endotelina-1/sangue , Endotelina-3/sangue , Feminino , Encefalopatia Hepática/fisiopatologia , Encefalopatia Hepática/terapia , Humanos , Hepatopatias/fisiopatologia , Hepatopatias/terapia , Falência Hepática Aguda/fisiopatologia , Falência Hepática Aguda/terapia , Masculino , Pessoa de Meia-Idade
12.
J Physiol ; 513 ( Pt 3): 907-13, 1998 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-9824727

RESUMO

1. Exercise reduces splanchnic blood flow, but the mesenteric contribution to this response is uncertain. 2. In nineteen humans, superior mesenteric and coeliac artery flows were determined by duplex ultrasonography during fasting and postprandial submaximal cycling and compared with the splanchnic blood flow as assessed by the Indocyanine Green dye-elimination technique. 3. Cycling increased arterial pressure, heart rate and cardiac output, while it reduced total vascular resistance. These responses were not altered in the postprandial state. During fasting, cycling increased mesenteric, coeliac and splanchnic resistances by 76, 165 and 126 %, respectively, and it reduced corresponding blood flows by 32, 50 and 43 % (by 0.18 +/- 0.04, 0.42 +/- 0.03 and 0.60 +/- 0.04 l min-1). Postprandially, mesenteric and splanchnic vascular resistances decreased, thereby elevating regional blood flow, while the coeliac circulation was not influenced. Postprandial cycling did not influence the mesenteric resistance significantly, but its blood flow decreased by 22 % (0.46 +/- 0.28 l min-1). Coeliac and splanchnic resistance increased by 150 and 63 %, respectively, and the corresponding regional blood flow decreased by 51 and 31 % (0.49 +/- 0.07 and 0.96 +/- 0.28 l min-1). Splanchnic blood flow values assessed by duplex ultrasound and by dye-elimination techniques were correlated (r = 0.70; P < 0.01). 4. During submaximal exercise in humans, splanchnic resistance increases and blood flow is reduced following a 50 % reduction in the hepato-splenic and a 25 % reduction in the mesenteric blood flow.


Assuntos
Artéria Celíaca/fisiologia , Exercício Físico/fisiologia , Circulação Esplâncnica/fisiologia , Adulto , Algoritmos , Ciclismo/fisiologia , Pressão Sanguínea/fisiologia , Débito Cardíaco/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Verde de Indocianina , Masculino , Período Pós-Prandial/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Resistência Vascular/fisiologia
14.
Hepatology ; 27(3): 666-73, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9500692

RESUMO

The magnitude of hepatic plasma flow in patients with liver failure and hepatic encephalopathy (HE) is unknown because a reliable flow estimate has not been available. The purpose of this study was to estimate hepatic plasma flow in patients with HE and to evaluate indocyanine green (ICG) and sorbitol as test compounds. Fourteen patients with acute liver failure (ALF) and nine patients with chronic liver failure (CLF), all with HE grade II or more, were studied. After hepatic vein catheterization, hepatic plasma flow was estimated by use of constant infusion, simultaneous arterial and hepatic vein concentration measurements, and calculated according to Fick's principle. The hepatic extraction fraction of D-sorbitol 0.179+/-0.144 (mean+/-SD) was higher than the hepatic extraction fraction of ICG 0.054+/-0.085 (P < .001). The low hepatic extraction fraction of ICG rendered this compound unfit for estimation of hepatic plasma flow in these patients. In contrast, by using D-sorbitol the hepatic plasma flow could be estimated in 21 of 23 patients with a median SD of 8.4% (range, 2.6% to 29%). The D-sorbitol estimated hepatic plasma flow was 1.2+/-0.5 L/min (n = 12) in patients with ALF and 1.4+/-0.9 L/min (n = 9) in patients with CLF. These values are higher than what has been reported in normal subjects and in patients with cirrhosis without HE. An elevated hepatic flow should increase oxygen delivery and may enhance the failing liver's ability to remove substances from the blood. At the same time, hepatic first pass metabolism is reduced. We conclude that an elevated hepatic flow in these patients is of clinical importance.


Assuntos
Corantes , Encefalopatia Hepática/fisiopatologia , Circulação Hepática , Compostos Orgânicos , Sorbitol , Adulto , Feminino , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade
15.
Hepatology ; 26(6): 1423-5, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9397981

RESUMO

In patients with acute liver failure, cerebral herniation is a common cause of death. The present study reports the effect of indomethacin on four occasions of intracranial hypertension, in a 23-year old previously healthy woman with severe acetaminophen poisoning. During each episode of intracranial hypertension, the patient was treated with 25 mg of indomethacin, and each time the intracranial pressure normalized. We recommend further controlled studies to determine the exact effect of indomethacin on cerebral blood flow and metabolism before it is recommended for treatment of intracranial hypertension in patients with acute liver failure.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Indometacina/uso terapêutico , Hipertensão Intracraniana/tratamento farmacológico , Pressão Intracraniana/efeitos dos fármacos , Falência Hepática/complicações , Doença Aguda , Adulto , Artérias Cerebrais/diagnóstico por imagem , Evolução Fatal , Feminino , Humanos , Hipertensão Intracraniana/fisiopatologia , Pressão Intracraniana/fisiologia , Ultrassonografia Doppler Transcraniana
16.
Ugeskr Laeger ; 159(46): 6815-9, 1997 Nov 10.
Artigo em Dinamarquês | MEDLINE | ID: mdl-9411993

RESUMO

Smoking during pregnancy is suggested as a cause of the increasing incidence rates of testis cancer in Denmark, particularly for the age group between 25 and 50. Testis cancer is associated with lower birthweights, as is smoking during pregnancy. Danish women have rates of everyday smoking amongst the highest in Europe, and the highest rate of smoking during pregnancy in Scandinavia, followed by Norway, Sweden and Finland. Incidence rates for testis cancer show the same sequence. The increasing incidence of testis cancer in Copenhagen was temporarily halted among men bom between 1939-1945 during the wartime tobacco shortage. The maternal generation aged about 25 years during the war years shows a corresponding delay in the increasing incidence of lung and bladder cancer, with a lag-time of respectively 20 and 30 years. The author recommends long-term followup of newborn boys prenatally exposed to tobacco.


Assuntos
Efeitos Tardios da Exposição Pré-Natal , Fumar/efeitos adversos , Neoplasias Testiculares/etiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Fatores de Risco
17.
Scand J Gastroenterol ; 32(3): 217-20, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9085457

RESUMO

BACKGROUND: Serum ethanol concentrations may become higher when alcohol is consumed during treatment with histamine receptor antagonists, especially if ethanol is ingested postprandially. Only a few studies have investigated fasting subjects, and women have only been investigated sporadically. METHODS: The present study compared serum ethanol concentrations after a 4-h fast followed by a low (0.15 g/kg) and a high (0.45 g/kg) dose of ethanol, on two separate occasions in six women and six men. The study was carried out before and after treatment with 400 mg cimetidine twice daily. RESULTS: Cimetidine administration did not change the area under the concentration-time curve or the maximal serum ethanol concentration in either women or men, irrespective of ethanol dose. Ethanol elimination rate was unchanged by cimetidine. CONCLUSION: Cimetidine does not influence the ethanol concentration-time curve when ethanol is ingested on an empty stomach.


Assuntos
Cimetidina/farmacologia , Etanol/sangue , Antagonistas dos Receptores H2 da Histamina/farmacologia , Adulto , Área Sob a Curva , Cimetidina/administração & dosagem , Etanol/administração & dosagem , Etanol/farmacocinética , Jejum , Feminino , Antagonistas dos Receptores H2 da Histamina/administração & dosagem , Humanos , Masculino
18.
Acta Oncol ; 36(1): 59-63, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9090968

RESUMO

Inquiry studies into smoking during pregnancy as a possible cause of testis cancer in sons are found misinterpreted as purely negative. Danish quinquennial incidence rates for patients aged 25-39 years are compared with rates for tobacco-induced neoplasms among the corresponding maternal generation, primarily of bladder tumours including papillomas, and of lung both for ages 50-64 years, allowing for period of latency. Corresponding to a delay of increase, earlier demonstrated for incidence rates of testis cancer among men born 1939-1945, delays of increase are found for female bladder and lung with allowance for lag-times of 30 and 20 years respectively. Comparison of data from Scandinavian nationwide cancer registries show a noteworthy parallelism of trends from first to last plotting of testis/female bladder ratios. The rise for lung is found steeper in consequence of age distribution.


Assuntos
Complicações na Gravidez , Fumar/efeitos adversos , Neoplasias Testiculares/epidemiologia , Neoplasias Testiculares/etiologia , Adulto , Idoso , Feminino , Humanos , Incidência , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/etiologia , Masculino , Pessoa de Meia-Idade , Gravidez , Sistema de Registros , Risco , Países Escandinavos e Nórdicos/epidemiologia , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/etiologia
19.
Eur J Gastroenterol Hepatol ; 9(1): 55-60, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9031900

RESUMO

OBJECTIVE: To evaluate the haemodynamic changes during treatment with high-volume plasmapheresis in patients with chronic liver failure compared to patients with acute liver failure. METHODS: Haemodynamic measurements were performed with a Swan-Ganz catheter and thermodilution technique. High-volume plasmapheresis (mean plasma exchange of 8.6 litres) was performed in 11 patients with chronic and 16 patients with acute liver failure. RESULTS: In patients with chronic liver failure, systemic vascular resistance index was unaltered: 1193 +/- 494 dynscm-5m2 before treatment versus 1180 +/- 399 dynscm-5m2 after. Mean arterial pressure increased from 69 +/- 11 mmHg to 78 +/- 13 mmHg (P < 0.05) and cardiac output increased from 8.1 +/- 2.4 l/min to 8.9 +/- 2.4 l/min (P < 0.05) during high-volume plasmapheresis. In patients with acute liver failure, systemic vascular resistance index increased from 1154 +/- 628 dynscm-5m2 to 1614 +/- 738 dynscm-5m2 (P < 0.001). In this group mean arterial pressure increased from 78 +/- 16 mmHg to 95 +/- 10 mmHg (P < 0.001) and cardiac output decreased from 9.6 +/- 3.7 l/min to 8.2 +/- 2.9 l/min (P < 0.01). CONCLUSION: The hyperkinetic circulation in chronic and acute patients was differently affected by high-volume plasmapheresis. We suggest that in chronic liver failure both portosystemic shunting and chronic peripheral vasodilation may contribute to the hyperkinetic syndrome, whereas in acute liver failure a humoral factor which can be removed by high-volume plasmapheresis is a main contributor.


Assuntos
Falência Hepática/fisiopatologia , Plasmaferese , Doença Aguda , Adulto , Bilirrubina/sangue , Gasometria , Cateterismo Venoso Central , Doença Crônica , Feminino , Hemodinâmica/fisiologia , Hemoglobinas/metabolismo , Humanos , Circulação Hepática , Falência Hepática/sangue , Falência Hepática/terapia , Masculino , Pessoa de Meia-Idade , Respiração Artificial , Resultado do Tratamento
20.
Ugeskr Laeger ; 158(48): 6892-5, 1996 Nov 25.
Artigo em Dinamarquês | MEDLINE | ID: mdl-8984750

RESUMO

Based on recent reports concerning the efficacy of N-acetylcysteine (NAC) in paracetamol (acetaminophen) poisoning, guidelines for treatment and control of these patients are reviewed by a study group under the Danish Association for the Study of the Liver. It is recommended that NAC-treatment is initiated immediately after referral and continued for 36 hours in all cases. Further NAC-treatment should not be discontinued before a decrease in INR has been observed.


Assuntos
Acetaminofen/intoxicação , Acetilcisteína/uso terapêutico , Analgésicos não Narcóticos/intoxicação , Antídotos/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Intoxicação/tratamento farmacológico , Acetilcisteína/administração & dosagem , Antídotos/administração & dosagem , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Dinamarca , Humanos , Infusões Intravenosas
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