Capnography is superior to pulse oximetry for the detection of respiratory depression during colonoscopy.

BACKGROUND: Pulse oximetry is a widely accepted procedure for ventilatory monitoring during gastrointestinal endoscopy, but this method provides an indirect measurement of the respiratory function. In addition, detection of abnormal ventilatory activity can be delayed, especially if supplemental oxygen is provided. Capnography offers continuous real-time measurement of expiratory carbon dioxide. OBJECTIVE: We aimed at prospectively examining the advantages of capnography over the standard pulse oximetry monitoring during sedated colonoscopies. PATIENTS AND METHODS: Fifty patients undergoing colonoscopy were simultaneously monitored with pulse oximetry and capnography by using two different devices in each patient. Several sedation regimens were administered. Episodes of apnea or hypoventilation detected by capnography were compared with the occurrence of hypoxemia. RESULTS: Twenty-nine episodes of disordered respiration occurred in 16 patients (mean duration 54.4 seconds). Only 38% of apnea or hypoventilation episodes were detected by pulse oximetry. A mean delay of 38.6 seconds was observed in the events detected by pulse oximetry (two episodes of disturbed ventilation were simultaneously detected by capnography and pulse oximetry). CONCLUSIONS: Apnea or hypoventilation commonly occurs during colonoscopy with sedation. Capnography is more reliable than pulse oximetry in early detection of respiratory depression in this setting.

Capnography is superior to pulse oximetry for the detection of respiratory depression during colonoscopy

Background: pulse oximetry is a widely accepted procedurefor ventilatory monitoring during gastrointestinal endoscopy, butthis method provides an indirect measurement of the respiratoryfunction. In addition, detection of abnormal ventilatory activitycan be delayed, especially if supplemental oxygen is provided.Capnography offers continuous real-time measurement of expiratorycarbon dioxide.Objective: we aimed at prospectively examining the advantagesof capnography over the standard pulse oximetry monitoringduring sedated colonoscopies.Patients and methods: fifty patients undergoing colonoscopywere simultaneously monitored with pulse oximetry and capnographyby using two different devices in each patient. Several sedationregimens were administered. Episodes of apnea or hypoventilationdetected by capnography were compared with the occurrence ofhypoxemia.Results: twenty-nine episodes of disordered respiration occurredin 16 patients (mean duration 54.4 seconds). Only 38% ofapnea or hypoventilation episodes were detected by pulse oximetry.A mean delay of 38.6 seconds was observed in the events detectedby pulse oximetry (two episodes of disturbed ventilationwere simultaneously detected by capnography and pulse oximetry).Conclusions: apnea or hypoventilation commonly occursduring colonoscopy with sedation. Capnography is more reliablethan pulse oximetry in early detection of respiratory depression inthis setting(AU)

Long-term reversal of hypocholesterolaemia in patients with chronic hepatitis C is related to sustained viral response and viral genotype.

BACKGROUND: Genotype-3 of hepatitis C virus (HCV) has been associated with serum lipid changes (reversible with sustained viral response) and liver steatosis. AIM: To characterize the relationships among hepatic steatosis, cholesterol and sustained viral response in these patients. METHODS: Patients (n = 215) with chronic hepatitis C (157 with genotype-1 of HCV) had age, body mass index, gender, alcohol intake, glycaemia, serum lipids, transaminases, grade and stage (METAVIR and Scheuer), degree of liver steatosis, sustained viral response, insulinaemia, leptinaemia, beta-hydroxybutyrate and glycerol measured, and were compared with 32 hepatitis B virus (HBV)-infected subjects. RESULTS: Genotype-3 of HCV patients had age-adjusted hypocholesterolaemia and more frequent hepatic steatosis (P < 0.001). Steatosis was inversely correlated with serum cholesterol (P < 0.01) and directly with viral load (P < 0.03). In patients with genotype-3 of HCV and sustained viral response, serum cholesterol increased from 138 (95% CI: 120-151) to 180 mg/dL (95% CI: 171-199) 12 months after treatment conclusion (P < 0.0001). By contrast, cholesterol values were unchanged in genotype-3 of HCV non-responders and in patients with genotype-1 of HCV regardless of response. Rising cholesterol in sustained viral response did not parallel the changes in beta-hydroxybutyrate. CONCLUSIONS: Besides causing hepatic steatosis, genotype-3 specifically decreases serum cholesterol. This interference with the metabolic lipid pathway is related to viral load, is reversed with sustained viral response, and seems unrelated to mitochondrial dysfunction.

Síndrome metabólico y progresión de la lesión hepática en la infección por el virus de la hepatitis C y el hígado graso no alcohólico / No disponible

No disponible

Diagnostic and therapeutic approach to cholestatic liver disease.

When cholestatic liver disease is present, liver ultrasound should be performed to ascertain if cholestasis is extrahepatic or intrahepatic. If bile ducts appear dilated and the probability of interventional treatment is high, endoscopic retrograde cholagio-pancreatography (ERCP) or trans-hepatic cholangiography (THC) should be the next step. If the probability of interventional therapeutics is low, cholangio-MRI should be performed. Once bile duct dilation and space occupying lesions are excluded, a work up for intrahepatic cholestasis should be started. Some specific clinical situations may be helpful in the diagnostic strategy. If cholestasis occurs in the elderly, drug-induced cholestatic disease should be suspected, whereas if it occurs in young people with risk factors, cholestatic viral hepatitis is the most likely diagnosis. During the first trimester of pregnancy cholestasis may occur in hyperemesis gravidorum, and in the third trimester of gestation cholestasis of pregnancy should be suspected. A familial history of recurrent cholestasis points to benign recurrent intrahepatic cholestasis. The occurrence of intrahepatic cholestasis in a middle-aged woman is a frequent presentation of primary biliary cirrhosis, whereas primary sclerosing cholangitis should be suspected in young males with inflammatory bowel disease. The presence of vascular spider nevi, ascites, and a history of alcohol abuse should point to alcoholic hepatitis. Neonatal cholestasis syndromes include CMV, toxoplasma and rubinfections or metabolic defects such as cystic fibrosis, alpha1-antitrypsin deficiency, bile acid synthesis defects, or biliary atresia. The treatment of cholestasis should include a management of complications such as pruritus, osteopenia and correction of fat soluble vitamin deficiencies. When hepatocellular failure or portal hypertension-related complications occur, liver transplantation should be considered.

Abordaje diagnóstico y terapéutico del síndrome colestásico / Diagnostic and therapeutic approach to cholestatic liver disease

Ante la presencia de colestasis, se debe determinar si su naturaleza es extra o intrahepática. Si la ecografía hepática no muestra dilatación de la vía biliar ni lesiones' ocupantes de espacio, se debe iniciar el estudio de una colestasis intrahepática. Si la obstrucción de la vía biliar extrahepática es cuestionable o la probabilidad de intervencionismo terapéutico es baja, se debe completar el estudio mediante colangio-pancreatografia-RM (CPRM). Si la probabilidad de intervencionismo es alta, se debe realizar colangiopancreatografía retrógrada endoscópica (CPRE) o colangiografía transparieto-hepática (CTPH). En caso de colestasis intrahepática, determinadas situaciones específicas ayudan a orientar el diagnóstico. Si la colestasis intrahepática ocurre en ancianos, se debe sospechar colestasis por fármacos, mientras que en pacientes jóvenes con antecedentes de riesgo, la hepatitis viral es la causa más frecuente. En el primer trimestre del embarazo la hiperemesis gravídica es la causa más probable y en el segundo o tercero la colestasis gravídica. La historia familiar y el curso recurrente deben orientar hacia una colestasis intrahepática recurrente benigna. La presencia de colestasis intrahepática en una mujer de edad media debe hacer sospechar CBP, mientras que en un varón joven con EIIC, una colangitis esclerosante primaria. La presencia de arañas vasculares, ascitis e historia de abuso de alcohol, apuntan hacia una hepatitis alcohólica como causa más probable. En el periodo neonatal, los síndromes colestásicos incluyen infecciones por CMV, toxoplasma, rubeola o defectos metabólicos como la fibrosis quística, el déficit de alfa1-antitripsina, defectos en la síntesis de ácidos biliares o atresia biliar. El tratamiento de la colestasis debe incluir el manejo de complicaciones como el prurito, la osteopenia y el déficit de vitaminas liposolubles. En caso de insuficiencia hepatocelular o complicaciones de la hipertensión portal, el manejo es similar al de otras etiologías y se debe valorar el trasplante hepático (AU)

When cholestatic liver disease is present, liver ultrasound should be performed to ascertain if cholestasis is extrahepatic or intrahepatic. If bile ducts appear dilated and the probability of interventional treatment is high, endoscopic retrograde cholagio-pancreatography (ERCP) or trans-hepatic cholangiography (THC) should be the next step. If the probability of interventional therapeutics is low, cholangio-MRI should be performed. Once bile duct dilation and space occupying lesions are excluded, a work up for intrahepatic cholestasis should be started. Some specific clinical situations may be helpful in the diagnostic strategy. If cholestasis occurs in the elderly, drug-induced cholestatic disease should be suspected, whereas if it occurs in young people with risk factors, cholestatic viral hepatitis is the most likely diagnosis. During the first trimester of pregnancy cholestasis may occur in hyperemesis gravidorum, and in the third trimester of gestation cholestasis of pregnancy should be suspected. A familial history of recurrent cholestasis points to benign recurrent intrahepatic cholestasis. The occurrence of intrahepatic cholestasis in a middle-aged woman is a frequent presentation of primary biliary cirrhosis, whereas primary sclerosing cholangitis should be suspected in young males with inflammatory bowel disease. The presence of vascular spider nevi, ascites, and a history of alcohol abuse should point to alcoholic hepatitis. Neonatal cholestasis syndromes include CMV, toxoplasma and rubinfections or metabolic defects such as cystic fibrosis, alpha1-antitrypsin deficiency, bile acid synthesis defects, or biliary atresia. The treatment of cholestasis should include a management of complications such as pruritus, osteopenia and correction of fat soluble vitamin deficiencies. When hepatocellular failure or portal hypertension-related complications occur, liver transplantation should be considered (AU)

Disturbed synthesis of insulinlike growth factor I and its binding proteins may influence renal function changes in liver cirrhosis.

Insulinlike growth factor-1 (IGF-1) is an anabolic hormone synthesized by the liver upon stimulation by growth hormone (GH). IGF-1 exerts important effects on renal hemodynamics and renal sodium handling. The bioactivity of this hormone is influenced by its binding proteins (BP) of which IGF-BP3 favors retention in the capillary lumen while IGF-BP1 facilitates the transport to the target tissues. IGF-BP1 modulates the actions of IGF-1 on target cells including renal tubules. Although a number of reports have dealt with disturbances of the IGF-1/IGF-BP system in cirrhosis, no studies have yet addressed the relationship between alterations in this system and renal function changes in cirrhosis. In the present study we have included 20 patients with cirrhosis and 10 healthy subjects (control group). As compared with the controls, patients showed lower circulating levels of IGF-1 and IGF-BP3, higher IGF-BP1 levels, and a tendency to higher insulinemia and GH values. The index IGF-1 x IGF-BP1/IGF-BP3 (IGF-1-IGF-BP index, reflecting the accessibility of circulating IGF-1 to target cells) was higher in patients with ascites. IGF-1 directly correlated with renal blood flow (P < 0.05), with IGF-BP3 (P < 0.001) and inversely with the Pugh's score (P < 0.02). A negative correlation was found between IGF-1-IGF-BP index and fractional sodium excretion (P < 0.01) and between IGF-BP1 and urinary sodium excretion (P < 0.02). Our findings support the hypothesis that the disturbance of the IGF-1/IGF-BP axis may be related to the degree of renal vasodilation and renal sodium retention in cirrhotic patients.

[Viability of colonoscopy without analgesia and conscious sedation]. / Viabilidad de la colonoscopia sin analgesia y sedación consciente.

AIM: To study the need for analgesia and sedation before colonoscopy. PATIENTS AND STUDY DESIGN: Fifty consecutive outpatients were randomly assigned to receive meperidine (0.7 mg/kg) or midazolam (0-035 mg/kg) intravenously (n = 25) or to receive no medication (n = 25) before colonoscopy. Oxygen saturation (SaO2) and heart rate were monitored. Mean blood pressure (MBP) was recorded before and after endoscopy. Patients in the group receiving no medication who experienced marked abdominal pain received sedation and analgesia similar to the premedicated group. Twenty-four hours after the procedure, the patients evaluated the degree of abdominal pain experienced during colonoscopy on a scale from 0 to 9. RESULTS: Complete colonoscopy was performed in 92% of the patients. No significant changes in heart rate were registered in either group. However, in the premedicated group mean blood pressure fell significantly (97.6 +/- 2.6 vs. 89.5 +/- 2.7 mmHg) before and after colonoscopy, respectively (p < 0.05). Nine patients experienced clinically relevant oxygen desaturation (SaO2 > 90%). Of these, five were from the premedicated group and four were from the group receiving no medication. In two patients, both from the premedicated group, the decrease in SaO2 was severe (SaO2 < 85%). The degree of abdominal pain was similar in both groups: 3.64_0.47 (premedicated) vs. 3.92 +/- 0.5 (non-medicated). In the non-medicated group, two patients required analgesia and sedation to complete the colonoscopy and 20 (80%) preferred not to receive sedation in future colonoscopies. CONCLUSIONS: Colonoscopy may be well tolerated without systematic administration of sedation and analgesia, which could be administered selectively.

Sustained response to interferon-alpha or to interferon-alpha plus ribavirin in hepatitis C virus-associated symptomatic mixed cryoglobulinaemia.

BACKGROUND: Hepatitis C virus (HCV) infection has been associated with mixed cryoglobulinaemia. AIM: To investigate the efficacy of anti-viral therapy on the eradication of HCV and its clinical manifestations in patients with HCV-associated symptomatic mixed cryoglobulinaemia. PATIENTS AND METHODS: 18 out of 32 patients with symptomatic mixed cryoglobulinaemia (MC group) received a 12-month course of interferon (3 MU three times a week, subcutaneously). Nonresponders or relapsers to this therapy were treated with interferon plus ribavirin (1200 mg/day, orally) for 12-months. 226 patients with HCV infection and without cryoglobulins were studied in comparison (Hepatitis C group). Serial quantification of serum HCV-RNA and cryoglobulins were performed. RESULTS: In the MC group, 10 out of 18 patients (55%) receiving interferon showed an end of treatment response, but at the end of follow-up, only five (28%) patients had a sustained response. In the hepatitis C group, 91 patients (47%) showed an end of treatment response but only 42 (20%) a sustained response. In the MC group alanine transaminase, cryocrit and rheumatoid factor decreased significantly in responders, with an improvement or disappearance of the MC-associated clinical manifestations. Alanine transaminase, cryocrit and rheumatoid factor increased in the relapsers and the clinical manifestations reappeared. Nonresponders and relapsers to interferon in the MC group were retreated with interferon plus ribavirin. Five out of eight nonresponders showed a end of treatment response but it was sustained in three of them. In the relapsers, treatment with combined therapy achieved a sustained response in four out of the five patients (80%). CONCLUSIONS: Interferon as monotherapy or combined with ribavirin is a safe and effective treatment in patients with HCV-associated MC. The presence of cryoglobulins does not affect the response to anti-viral treatment in patients with HCV infection. The eradication of HCV is associated with an improvement or disappearance of MC-associated clinical manifestations.

Propranolol plus prazosin compared with propranolol plus isosorbide-5-mononitrate in the treatment of portal hypertension.

BACKGROUND & AIMS: The association of prazosin to propranolol enhances the decrease in portal pressure but may cause hypotension and sodium retention. The aim of this study was to compare the portal pressure reduction and safety of the combination of propranolol plus prazosin with that of propranolol plus isosorbide-5-mononitrate (ISMN). METHODS: Fifty-six portal-hypertensive cirrhotics received randomly propranolol plus prazosin (n = 28) or propranolol plus ISMN (n = 28) orally for 3 months. Hemodynamics and liver and renal function were assessed at baseline and after 3 months. RESULTS: Propranolol plus prazosin caused a greater reduction in hepatic venous pressure gradient (HVPG) than propranolol plus ISMN (-24.2% +/- 11% vs. -16.1% +/- 11%; P < 0.01). A reduction in HVPG of > 20% was significantly more frequent in the propranolol plus prazosin group than in the propranolol plus ISMN group (85% vs. 53%; P < 0.05). Neither treatment modified hepatic blood flow, quantitative liver function test results, glomerular filtration rate, plasma renin activity, or plasma aldosterone level. Side effects occurred in 13 patients receiving propranolol plus prazosin compared with 7 receiving propranolol plus ISMN (P = 0.16). CONCLUSIONS: Propranolol plus prazosin has a greater portal pressure-lowering effect than propranolol plus ISMN. Both therapies were safe for liver and renal function. However, the combination of propranolol plus prazosin caused a greater decrease in arterial pressure and was less well tolerated than propranolol plus ISMN.

Selective impairment of endothelium-mediated vasodilation in liver transplant recipients with cyclosporin A-induced hypertension.

Arterial hypertension is commonly observed in orthotopic liver transplantation (OLT) recipients receiving cyclosporin A (CsA), but the precise pathogenetic mechanisms remain partially unknown. The aim of this study was to investigate endothelium-dependent and -independent dilation and adrenergic constriction of resistance vessels of OLT recipients treated with CsA. Vascular reactivity was examined in 22 OLT patients, 10 with and 12 without arterial hypertension, and in 10 control subjects by assessing the forearm blood flow response to the brachial artery infusion of increasing concentrations of methacholine chloride, sodium nitroprusside, and phenylephrine. In 10 OLT patients, the response to methacholine was also examined after acetylsalicylate. The ratio of serum nitrite and nitrate to serum creatinine was lower (P < .05) in OLT patients with hypertension than in nonhypertensive patients and controls. Basal forearm flow was similar in the three groups. Methacholine vasodilation was impaired in the hypertensive patients as shown by a lower maximum forearm vasodilator response and a shift in the dose response curve to methacholine to the right compared with the nonhypertensive OLT patients and the controls. The response to methacholine was not modified after salicylate. Forearm flow response to nitroprusside was similar in the three groups. No differences between the patients and the controls were found in the maximum forearm flow contraction in response to phenylephrine. An impairment in endothelium-dependent vasodilation could mediate arterial hypertension in OLT patients immunosuppressed with CsA.

Accuracy of portal and forearm blood flow measurements in the assessment of the portal pressure response to propranolol.

BACKGROUND/AIMS: The portal pressure response to propranolol varies significantly in individual patients with cirrhosis. At present, propranolol responders can be identified only by measuring the hepatic venous pressure gradient. The aims of this study were: 1) to investigate whether the noninvasive monitoring of portal blood flow by pulsed Doppler ultrasound and forearm blood flow by strain-gauge plethysmography can predict the hepatic venous pressure gradient response to propranolol in patients with cirrhosis, and 2) to analyze the factors that may influence this response. METHODS: Hemodynamic measurements were undertaken in 80 patients with cirrhosis before and after receiving propranolol (0.15 mg/kg i.v., n = 60) or placebo (n = 20). RESULTS: No changes were observed in the placebo group. Propranolol lowered (p < 0.01) hepatic venous pressure gradient from 17.6 +/- 3.8 to 14.7 +/- 3.8 mmHg, portal blood flow from 1122 +/- 363 to 897 +/- 332 ml/min and forearm blood flow from 7.52 +/- 3.1 to 6.12 +/- 2.3 ml/min%. Changes in hepatic venous pressure gradient were correlated (p < 0.01) with those of portal blood flow (r = 0.82) and forearm blood flow (r = 0.54). The reduction in hepatic venous pressure gradient was > 20% in 23 patients ("responders"). The accuracy of portal Doppler flowmetry in identifying responders was higher than that of forearm plethysmography (88.3 vs. 68.3%, p < 0.05). Multivariate analysis proved that previous variceal bleeding was the only factor independently associated with a lack of response to propranolol (relative risk 3.42, 95% CI 1.5-7.4, p < 0.01). Hepatic venous pressure gradient reduction by propranolol was higher in non-bleeders than in bleeders (-19.9 +/- 9.4 vs. -11.3 +/- 8.6%, p < 0.01). CONCLUSIONS: Portal Doppler ultrasound can be used as a reliable surrogate indicator of the hepatic venous pressure gradient response to acute propranolol administration. In addition, our study indicates that this response is mainly influenced by previous variceal hemorrhage.

Changes in gastrin and serum pepsinogens in monitoring of Helicobacter pylori response to therapy.

The aims of this study in 50 patients with H. pylori infection and duodenal ulcer were to examine the effect of eradication therapy on the serum levels of gastrin, pepsinogen I, and pepsinogen II and to investigate whether monitoring of the serum changes in these peptides after treatment could predict patient outcome. H. pylori status was assessed at entry and one and six months after therapy by culturing and microscopic analysis of the gastric mucosa and by [14C]urea breath test. Significant decreases were observed in the serum levels of gastrin (-11.4 +/- 3%), pepsinogen I (-28.9 +/- 4%), and pepsinogen II (-40.4 +/- 3%) in the 45 patients whose infection was eradicated, but not in the patients without eradication. Serum values of these peptides were unchanged in an additional group of 10 patients that only received omeprazol, none of whom had H. pylori eradicated. The best cutoff point of the percentage of each peptide to predict patient outcome was 10% for gastrin and pepsinogen I, and 15% for pepsinogen II. A pepsinogen II decrease > 15% resulted in the best marker of H. pylori clearance, accurately identifying patient outcome 86.6% of the time, whereas the diagnostic accuracy of gastrin and pepsinogen I was 61.7% and 76.6%, respectively. Significant correlations were found between the bacterial load assessed by histology with the serum concentrations of pepsinogen I and II and with the urease activity as measured by the amount of 14CO2 excreted. In conclusion, eradication of H. pylori infection is followed by a significant drop in serum levels of gastrin, pepsinogen I, and pepsinogen II. Changes in the latter are the most uniform and may be used as an indirect tool to predict treatment outcome.

Arterioportal fistula and hemobilia with associated acute cholecystitis: a complication of percutaneous liver biopsy.

Complications attributable to percutaneous liver biopsy, including hemobilia and arterioportal fistula, are uncommon. In this report, we present the case of a patient who underwent percutaneous liver biopsy and, as a consequence of this procedure, developed an arterioportal fistula and hemobilia with associated acute cholecystitis. The diagnosis of hemobilia was possible with abdominal ultrasound and upper endoscopy, but the patient required cholecystectomy. Hepatic angiography was performed, demonstrating the arterioportal fistula and hemobilia. Transcatheter embolization occluded the fistula, resolving the hemobilia. We recommend ultrasound and upper endoscopy as initial diagnostic procedures, but angiography and selective embolization must not be delayed if arterioportal fistula and/or hemobilia is suspected since these measures may help to prevent further complications.

Interferon and prednisone therapy in chronic hepatitis C with non-organ-specific antibodies.

BACKGROUND/AIMS: The relationship between hepatitis C virus and autoimmunity is controversial. The issue is particularly relevant in those patients with hepatitis C virus infection and serum autoantibodies in whom steroids can exacerbate viral replication and interferon can lead to decompensated liver disease. The aim of this study was to evaluate the response to a course of prednisone or interferon-alpha 2b. METHODS/RESULTS: The 12 study patients had biopsy-proven chronic hepatitis, serum HCV-RNA (by nested polymerase chain reaction) and non-organ-specific antibodies (eight with liver and kidney microsomal antibodies and four with antinuclear antibodies). Eight of these 12 patients received a 4-month course of prednisone (0.5 mg/kg per day), which increased alanine aminotransferase (mean +/- SE) (174 +/- 31 vs 252 +/- 18 U/l, p < 0.05) and bilirubin levels (0.96 +/- 0.17 vs 1.42 +/- 0.18 mg/dl, p = 0.09), without changing liver histology (Knodell index, 13.6 +/- 0.4 vs 13.1 +/- 0.3). Subsequent treatment with interferon in the 12 patients reduced serum alanine aminotransferase levels (170 +/- 20 vs 41 +/- 7 U/l, p < 0.0001) and portal and lobular inflammation (Knodell index, 13.8 +/- 0.5 vs 8.4 +/- 0.2, p < 0.001). A complete response to interferon was observed in ten of these patients (83%), eight of whom had previously been treated with prednisone. Serum HCV-RNA level decreased in interferon responders. A sustained response 1 year after withdrawal of interferon was seen in only five patients (41%). CONCLUSIONS: Patients with chronic hepatitis C and autoantibodies show a favorable response to interferon, but not to prednisone. The latter regimen can exacerbate liver necrosis in these subjects. The presence of autoantibodies in hepatitis C patients does not modify the response to interferon.

Peritoneal dialysis in liver disorders.

The purposes of this paper is to review the specific role of peritoneal dialysis (PD) in patients with liver disorders. We will pay attention to the confluence of liver diseases and situations for which chronic dialysis treatment is required. Hemodialysis (HD) and peritoneal membranes are safe barriers against the passage of the hepatitis C virus; consequently, while peritoneal effluent or HD ultrafiltrate drained from hepatitis B patients/carriers is infective, that from hepatitis C patients does not appear to present this risk. An important issue is horizontal transmission, which appears to occur with both viruses in HD units, and which is absent in peritoneal dialysis units. The incidence of hepatitis C among continuous ambulatory peritoneal dialysis (CAPD) patients is quite low, while it may reach almost 50%-60% of HD patients in some units. While hepatitis C transmission mechanisms are not completely understood and a vaccine is not available, PD provides some degree of protection when compared with HD, for and-stage renal disease patients. In summary, our experience and that of others, with a total of 19 PD-treated chronic liver disease patients, supports CAPD as the treatment of choice for cirrhotic patients with ascites who require chronic dialysis. Data on peritoneal diffusion of low molecular weight substances revealed a marked increase in most patients. The ultrafiltration capacity was clearly augmented with respect to noncirrhotic patients, making the use of hypertonic bags unnecessary. Hemodynamic tolerance was excellent. Complications and death were mainly related to liver disease complications. Spontaneous bacterial peritonitis (SBP), caused by gram-negative germs, is the most important complication directly related to ascites and may have some points in common with PD-related peritonitis. However, and in contrast to most PD peritonitis, two pathogenetic mechanisms have been suggested for SBP: (1) translocation of bacteria from the gut to the mesenteric lymph nodes, and (2) bacteremia in these patients is secondary to the general abnormal host defense mechanisms. Local factors such as intrahepatic shunting and the impairment of bactericidal activity in ascitic fluid favor the bacteria ascites. The hypothesis of a direct transmural contamination from bowel to ascitic fluid has been relegated to secondary bacterial peritonitis. Would cirrhotic patients with temporal or permanent renal function compromise benefit from peritoneal catheter placement and other PD practices to perform repetitive small ascitic drainages at home? Perhaps the time has arrived when hepatologists and PD nephrologists begin to work shoulder to shoulder in this particular field, as we have a common problem, the peritoneal cavity filled with fluid.

Enhanced endothelium-dependent vasodilation in patients with cirrhosis.

Experimental evidence indicates that an increased production of nitric oxide could play a role in the peripheral vasodilation of portal hypertension. To test this hypothesis in humans, we studied basal serum NO(2-) + NO3- levels and the response of forearm resistance vessels to increasing concentrations of methacholine chloride, sodium nitroprusside, and phenylephrine infused into the brachial artery of 12 cirrhotic patients and 10 controls. Forearm vascular resistance (FVR) was calculated from mean arterial pressure and forearm blood flow (FBF). Cirrhotics showed higher NO(2-) + NO3- levels (P < 0.05), higher FBF (P < 0.01), and lower FVR (P < 0.01) than controls. The reduction of FVR in response to every dose of methacholine was greater in cirrhotics than in controls; this was significant (P < 0.05) at the 3 and 10 micrograms/min doses. This response to methacholine was not modified by blockade of vascular prostacyclin. The response to nitroprusside was similar in both groups. The increase in FVR in response to every dose of phenylephrine was significantly (P < 0.01) lower in cirrhotics than in controls. In cirrhotics, a significant correlation (r = -0.81, P < 0.01) was found between the FVR response to the highest doses of methacholine and phenylephrine. In conclusion, cirrhotic patients show an enhanced endothelium-mediated vasodilation, which suggests an increased synthesis of nitric oxide. This defect may mediate the peripheral vasodilation and hyporeactivity to vasopressors of these patients.