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J Wendon

Publications and source records attributed to J Wendon.

At least 37 records · Page 2Linked to original sources
PubMed1997

Auxiliary partial orthotopic liver transplantation for acute liver failure.

BACKGROUND/AIMS: Auxiliary partial orthotopic liver transplantation holds potential advantages over conventional orthotopic liver transplantation, but experience with the technique in acute liver failure is limited. METHODS: We describe our initial experience in seven patients (4 men, 3 women; mean age 28, range 14-35 years) with acute liver failure (paracetamol 3, non A-E 2, autoimmune 1, Ecstasy 1) who fulfilled criteria for emergency transplantation. Preoperatively, the median international normalised ratio was seven (range 3.4-15), with a creatinine of 123 microM (51-389 microM) and bilirubin 320 microM (61-572 microM). The reasons for performing an auxiliary transplant were the patients' young age and stable preoperative condition (n = 5), or a significant psychiatric history precluding conventional transplantation (n = 2). RESULTS: All patients received blood group-matched left (n = 2) or right (n = 5) auxiliary grafts. Median duration of surgery was 8.5 h (7.3-10 h), with blood loss of 8.3 litres (4.6-14.6 litres). Post-transplant, the international normalised ratio and aspartate aminotransferase fell progressively in all patients, with median values at day 7 of 1.4 (1.0-2.4) and 108 IU/1 (78-910 IU/1). Three patients died from sepsis within the first postoperative month. At 2 weeks, four of six patients had partial regeneration of the native liver, which became complete in two of the survivors by 1 year. CONCLUSIONS: Although patient selection remains poorly defined, auxiliary partial orthotopic liver transplantation in acute liver failure is technically feasible and, in some patients, allows native liver regeneration and eventual immunosuppression withdrawal.

Acute Disease↗
PubMed1996

Coagulation factor V levels as a prognostic indicator in fulminant hepatic failure.

Data reported by Bernuau et al. have strongly supported the measurement of coagulation factor V as the best prognostic indicator in fulminant hepatic failure (FHF) and as the test on which selection for urgent liver transplantation should be made. In this study, we have measured plasma factor V in 110 patients with FHF, in grades I-IV coma, in 88 of whom the etiology was acetaminophen overdose. On admission, patients who did not survive had significantly lower factor V levels (median, 5%; range, 1-27; n = 49), compared with those who did (median, 10%; range, 2-70; P < .001). In the 81 patients with acetaminophen-induced FHF who did not receive a transplant, there was no cutoff level of factor V that clearly separated the patients. On statistical analysis, a positive predictive value (the mortality in patients predicted to have a poor prognosis) of 0.49 was calculated for factor V <20% and 0.57 for factor V < 10%. If the prognostic criteria included deep coma (grades III and IV) as well as factor V <20%, a positive predictive value of 0.73 was calculated. This compared with a value of 0.92 for the well-established King's prognostic criteria based on pH, and a combination of international normalized ratio (INR), renal failure, and coma. In the 17 mixed, nonacetaminophen group of patients who did not receive a liver graft, the positive predictive value was 0.85 for a factor V level <20% and 1.00 for factor V <10%, compared with 0.93 for the King's criteria for that etiologic group. This study demonstrates that the predictive accuracy of plasma factor V level is much less effective than the well-validated King's criteria in the selection of patients with acetaminophen-induced FHF needing liver grafting, although it may be useful in patients with FHF due to other causes.

Acetaminophen↗
PubMed1996

Prospective study comparing the efficacy of prophylactic parenteral antimicrobials, with or without enteral decontamination, in patients with acute liver failure.

The efficacy of prophylactic parenteral antibacterials, with or without selective decontamination of the digestive tract, was compared in patients with acute liver failure (ALF) or severe acetaminophen hepatotoxicity. One hundred eight patients were randomized on admission to receive intravenous ceftazidime and flucloxacillin, plus either oral and enteral decontamination with colistin, tobramycin, and amphotericin B (group 1), or enteral amphotericin B alone (group 2). The two groups were comparable with respect to age, gender, etiology, coma grade on admission, international normalization ratio, presence of renal failure, Acute Physiology and Chronic Health Evaluation II score, and indicators of poor prognosis. Patients were monitored for clinical and microbiological evidence of infection. There were 15 episodes of infection in 10 of 47 patients (21%) in group 1 and 17 episodes in 12 of 61 patients (20%) in group 2. No differences in incidence, site, and causative organisms of infection were observed between the two groups. Overall, the incidence of infection was significantly higher in patients who developed encephalopathy than in those who did not. In patients who on arrival were not encephalopathic, the development of infection was associated with progression to coma. Duration of Liver Intensive Care Unit (LICU) stay was an independent risk factor for the development of infection. Parenteral antibiotics are effective at reducing the risk of infection in patients with ALF; enteral decontamination provided no additional benefit.

Adolescent↗
PubMed1996

Evidence of increased guanylate cyclase activation by acetylcysteine in fulminant hepatic failure.

Patients with fulminant hepatic failure (FHF) have a severe microcirculatory disturbance causing tissue hypoxia. Infusion of acetylcysteine improves survival and reduces the incidence of multiorgan failure by enhancing tissue oxygenation. Because the observed circulatory effects of acetylcysteine in FHF are similar to and synergistic with those produced by the microcirculatory vasodilator prostacyclin, we postulated that acetylcysteine might potentiate an endogenous vasodilator. Nitric oxide, a vasodilator that activates soluble guanylate cyclase, is a possible candidate as plasma cyclic 3',5'-guanosine monophosphate (cGMP) is raised in FHF, and in vitro acetylcysteine has been found to enhance soluble guanylate cyclase activity. To investigate this possible mechanism further, plasma cGMP was measured before and after acetylcysteine infusion in 24 patients with FHF and again in 6 patients after recovery from acute illness. cGMP levels were high in FHF during acute illness (median, 7.0 nmol/L [interquartile range, 2.6-10.0]) in comparison with levels taken after recovery (1.5 nmol/L [1.0-1.9]; P < .05). Levels rose further after acetylcysteine infusion in the FHF cases (mean increase, 204% [95% CI; 49 to +360]; P < .01) but not in the cases after recovery (38% [-7 to +84]). There were no significant changes in levels of plasma atrial natriuretic peptide (ANP) or cyclic adenosine monophosphate (cAMP) (mean increases, 8% [-6 to +22] and 17% [-9 to +43], respectively). The findings further support the hypothesis that the beneficial hemodynamic effects of acetylcysteine in FHF are mediated by enhancing the activity of the nitric oxide/soluble guanylate cyclase enzyme system.

Acetylcysteine↗
PubMed1996

Circulatory, respiratory, cerebral, and renal derangements in acute liver failure: pathophysiology and management.

Many of the hemodynamic abnormalities seen in acute liver failure (ALF) have now been characterized. A lowered systemic vascular resistance with a raised cardiac output are prominent features, which in part are modulated by nitric oxide (NO). At a cellular level, oxygen supply and utilization are impaired by changes in vascular tone, plugging of nutritive vessels, and pathological shunting. The use of N-acetylcysteine (NAC) and prostacyclin, a vasodilator, have been shown to increase oxygen utilization in the microcirculation. NAC may act by enhancing the effect of NO on guanylate cyclase, increasing the formation of cyclic 3',5'-guanosine monophosphate (cGMP), and thereby resulting in vasodilatation. This suggests that despite overproduction of NO in ALF, there is a short-age/ failure of utilization at a cellular level. Appropriate management of these patients should be based on a good knowledge of the underlying pathophysiology, and thus on monitoring, during the course of the disease.

Blood Circulation↗
PubMed1995

Anti-tuberculous therapy and acute liver failure.

The incidence of tuberculosis has been increasing since 1987, exposing a greater number of patients to the risks of three potentially hepatotoxic drugs, isoniazid, rifampicin, and pyrazinamide. Awareness of potentially severe drug hepatotoxic reactions is vital because fulminant hepatic failure is a devastating and often fatal condition without liver transplantation. We report four cases of fulminant hepatic failure caused by rifampicin, isoniazid, or both. These cases highlight the need for stricter adherence to and review of current guidelines on liver function tests after starting anti-tuberculous therapies.

Adult↗
PubMed1995

A 7-year experience of severe acetaminophen-induced hepatotoxicity (1987-1993).

BACKGROUND & AIMS: Five hundred sixty patients admitted between January 1, 1987, and December 31, 1993, with severe acetaminophen-induced hepatotoxicity were studied. The aim of this study was to identify why severe acetaminophen-induced hepatotoxicity still occurs and to determine how known risk factors and advances in management have affected the pattern of illness and outcome. METHODS: This was a retrospective study of the etiologic factors and the clinical course of all acetaminophen-related admissions. RESULTS: The number of admissions increased from 58 in 1987 to 123 in 1993. During the corresponding period, overall survival improved from just < 50% to 78%. The percentage of admissions treated with N-acetylcysteine increased from 40% in 1987 to 83% in 1993. The frequency with which grade III or IV encephalopathy developed decreased from 62% in 1987 to 40% in 1993, and the percentage of these patients who developed cerebral edema decreased from 61% to 45% during the same period. There was an increase in both the number of patients transplanted and the survival of those managed medically. CONCLUSIONS: Severe acetaminophen-induced hepatotoxicity remains a serious condition, but the increasing use of N-acetylcysteine, advances in medical management, and the increasing availability of transplantation have resulted in a significant improvement in survival rates.

Acetaminophen↗
PubMed1995

Pretransplantation clinical status and outcome of emergency transplantation for acute liver failure.

Emergency transplantation for acute liver failure has a significantly inferior outcome than transplantations performed for elective indications. The severity of the pretransplantation clinical illness in this group will contribute to the reduced patient survival. We have reviewed the outcome of our first 100 consecutive adult patients who received transplants for acute liver failure and have evaluated and determined which recipient clinical parameters present on admission and at transplantation act as risk factors in early posttransplantation outcome. In patients who received transplants for nonacetaminophen-induced liver failure (n = 79), no static variable determinable on admission (including age, sex, year of transplantation, hospital admission to transplantation period, and fulminant or late-onset presentation) other than cause was predictive of 2-month patient survival. Fulminant Wilson's disease and idiosyncratic drug reactions with 2-month survival rates of 100% and 12.5%, respectively, had significantly different outcomes from other causes. By the time of transplantation, of four dynamic variables significant in a univariate analysis (serum creatinine, encephalopathy grade, Apache 111 and organ system failure scores, and P values < .05), only the creatinine level was an independent variable in a stepwise logistic regression for 2-month survival (r = .33). In patients who received transplants for acetaminophen hepatotoxicity (n = 21), overdose to hepatectomy period was the only significant static variable, with no parameter predictive of outcome present on admission.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetaminophen↗
PubMed1994

Indications for orthotopic liver transplantation in fulminant liver failure.

The decision to undertake transplantation in a patient with fulminant liver failure requires consideration of many factors so that the physician may arrive at the most appropriate course of action. There are several definitions of fulminant liver failure used in current practice, all excluding patients with chronic liver disease. In the one most recently proposed, the terms hyperacute, acute and subacute liver failure are used to categorize groups of patients with different clinical appearances and progress. Patients in the hyperacute group have a better outcome with medical treatment than others, despite deeper levels of encephalopathy. The decision to proceed to transplantation should be undertaken in patients who fulfil criteria for a poor prognosis with medical management. For two groups, Hôpital Paul Brousse, Paris, and King's College Hospital, London, criteria are based on analysis of large patient numbers, which can be applied at the bedside without recourse to complex analysis. Once a patient has been listed for transplantation, regular systems review must be undertaken because the development of irreversible multiple organ failure may preclude transplantation. Hepatectomy may occasionally have a role in stabilizing a patient awaiting a suitable organ. In less severe cases, auxiliary liver transplantation has been undertaken, and in some patients regeneration of the native liver has occurred, allowing withdrawal of immunosuppressive therapy. The results of orthotopic liver transplantation in fulminant liver failure have steadily improved over recent years, with reported 1-year survival rates of up to 80% in some series, yielding a good prognosis for certain groups of patients who previously had unacceptably high mortality.

Contraindications↗
PubMed1994

Fulminant hepatic failure secondary to hydroxychloroquine.

Hydroxychloroquine is widely used in rheumatological disease but hepatic side effects have not been reported previously. Two cases are described of fulminant hepatic failure developing after the start of hydroxychloroquine treatment for a chronic rheumatological disorder. In both cases the symptoms of liver disease developed within two weeks of starting hydroxychloroquine and rapidly progressed to fulminant hepatic failure and in neither case was there any pre-existing liver disease. One patient had emergency orthotopic liver transplantation and the other died before a donor organ became available.

Adolescent↗
PubMed1993

Metabolic effects of beta-adrenergic receptor blockade in advanced alcoholic cirrhosis.

It has been postulated that the adverse metabolic effects of beta-adrenergic blockade with propranolol in cirrhosis may be related to altered delivery and utilisation of oxygen, particularly in patients with advanced alcoholic liver disease (ALD). Consequently, in 10 patients with decompensated ALD, we assessed (a) systemic and hepatic oxygen delivery (DO2), extraction ratio (%O2E) and consumption (VO2), (b) myocardial VO2 (assessed by the rate-pressure product [RPP], together with full systemic and splanchnic haemodynamics) and (c) hepatic redox state (HRS), measured indirectly by the arterial ketone body ratio (KBR i.e. ratio of acetoacetate/beta-hydroxybutyrate), prior to and following intravenous propranolol (0.1-2 mg/kg). Results are expressed as mean +/- S.E.M. Propranolol reduced DO2 (700 +/- 33 vs. 583 +/- 32 ml/min/m2, p < 0.05) and myocardial VO2 (RPP 72 vs. 58, p < 0.05). The %O2E increased however, (18.5 +/- 1.3 vs. 22.6 +/- 1.6%, p < 0.05), resulting in unaltered systemic VO2 (127 +/- 7.3 vs. 131 +/- 6.9 ml/min/m2, p > 0.10). Similarly hepatic VO2 did not change. KBR was not altered (0.44 +/- 0.08 vs. 0.48 +/- 0.07), and in fact improved in two patients (Child C12 and C13) from 0.17 to 0.34 and 0.12 to 0.27, respectively. In conclusion, the results of this study suggest that an underlying O2 debt exists in patients with advanced alcoholic cirrhosis and that beta-adrenergic blockade with propranolol 'normalises' the O2 supply-consumption relationship resulting in more efficient O2 utilisation without adversely affecting HRS. The mechanism of this action may be related to the antagonism of beta 2-mediated arteriovenous shunting resulting in appropriate blood redistribution.

Adult↗
PubMed1992

Plasma endothelin immunoreactivity in liver disease and the hepatorenal syndrome.

BACKGROUND: Severe renal vasoconstriction is central to the pathogenesis of renal failure in the hepatorenal syndrome. Endothelin-1 and endothelin-3 are potent, long-acting vasoconstrictors, and endothelin-1 has selective potency as a renal vasoconstrictor. These properties suggest a role for endothelins in the hepatorenal syndrome. METHODS: We measured plasma endothelin-1 and endothelin-3 concentrations using specific radioimmunoassays in subjects with hepatorenal syndrome, liver disease but normal renal function, chronic renal failure, acute renal failure, liver dysfunction and renal impairment, or normal liver and kidney function. RESULTS: The patients with the hepatorenal syndrome had markedly elevated mean (+/- SE) plasma concentrations of endothelin-1 (36 +/- 5 ng per liter [14.5 +/- 1.8 pmol per liter]) and endothelin-3 (43 +/- 3 ng per liter [16.3 +/- 1.0 pmol per liter]) as compared with the normal subjects (endothelin-1, 4 +/- 1 ng per liter [1.7 +/- 0.2 pmol per liter]; and endothelin-3, 18 +/- 1 ng per liter [6.8 +/- 0.4 pmol per liter]; P < 0.001) and with the patients in the other four groups (P < 0.001 to P < 0.05). The plasma endothelin-1, but not endothelin-3, concentrations in these four patient groups were significantly higher than in the normal subjects (P < 0.001 to P < 0.05). The concentrations of endothelin-1 in renal arterial plasma and renal venous plasma, measured in five patients with the hepatorenal syndrome and three with chronic liver disease and normal renal function, were 20 +/- 4 ng per liter (7.9 +/- 1.8 pmol per liter) and 24 +/- 4 ng per liter (9.5 +/- 1.5 pmol per liter), respectively (P < 0.05). CONCLUSIONS: The increase in plasma endothelin-1 and endothelin-3 concentrations in patients with the hepatorenal syndrome is consistent with the hypothesis that these substances have a role in the pathogenesis of the disease.

Acute Kidney Injury↗
PubMed1991

Liver transplantation after paracetamol overdose.

OBJECTIVE: To evaluate the role of liver transplantation after paracetamol overdose. DESIGN: Prospective study of consecutive candidates for transplantation and performance of transplantation over 18 months. SETTING: Liver unit, King's College Hospital, London. MAIN OUTCOME MEASURES: Fulfilment of indicators of poor prognosis, selection for transplantation, transplantation, survival. RESULTS: 30 of 37 patients considered to have a reasonable prognosis with intensive medical care survived. Of 14 of 29 patients considered to have a very poor prognosis and registered for urgent liver transplantation, six received liver transplants, four of whom survived, while seven died and one survived without a transplant. Three of 15 patients with poor prognostic indicators but not selected for transplantation survived. CONCLUSION: Liver transplantation will have a definite but limited role in the management of fulminant hepatic failure induced by paracetamol.

Acetaminophen↗
PubMed1989

Continuous high volume venous-venous haemofiltration in acute renal failure.

Continuous, high volume, venous-venous haemofiltration was used as renal support in 28 critically ill patients with acute renal failure. Fifteen patients survived and were subsequently discharged from the ITU. Although haemofiltration was highly effective in reducing the blood urea and serum creatinine, only survivors demonstrated a significant increase in arterial pH (medians before and at two days 7.28 and 7.49 respectively, p less than 0.005) with a reduction in severity of their illness (median APACHE II scores before and at two days 23 and 16, p less than 0.005). Patients who died remained severely ill and acidotic (median APACHE II scores before and at two days 26 and 28; median arterial pH values 7.32 and 7.31 respectively) and by day two of treatment, marked differences between the patient groups in APACHE II scores, mean arterial pressure, arterial pH and urine flow rate had developed. Haemofiltration with the correction of acute uraemia alone does not necessarily lead to a reduction in the severity of illness which in the critically ill more frequently reflects other organ dysfunction.

Acute Kidney Injury↗