Search PubMed⌕ Search

Biomedical subjects

P McMaster

Publications and source records attributed to P McMaster.

At least 37 records · Page 2Linked to original sources
PubMed2000

Normalised intrinsic mortality risk in liver transplantation: European Liver Transplant Registry study.

BACKGROUND: No model exists for liver transplantation to estimate the mortality risk in a given patient, and no standard by which to assess performance in different centres. We investigated the intrinsic mortality risk in the absence of known mortality risk factors. METHODS: We identified mortality risk factors and risk ratios quantified in data from the European Liver Transplant Registry (22,089 patients at 102 centres in 18 countries) registered from 1988 to 1997. To develop a model of the intrinsic risk and the risk ratios for specific factors, univariate and multivariate analyses were done separately for the overall population, for adults, and for children younger than 15 years, and the number of deaths were estimated. We validated the model by comparing mortality in patients without risk factors with the model-adjusted mortality in patients with risk factors. FINDINGS: Overall 5-year and 8-year actuarial survival was 66% (95% CI 65-66) and 61% (60-62). 65% of deaths occurred within 6 months. Retransplantation, transplantation for cancer, acute liver failure, fewer than 20 split-liver grafts per year, and a centre workload of fewer than 25 transplants per year were the main risk factors of 12 identified factors. 1-year and 5-year death rates among adults with no risk factors were similar to model estimates (15 [13-16] vs 14% [13-15], and 22 (20-24) vs 23% [21-24]). Corresponding data for paediatric transplants were 9% (7-12) compared with 11% (9-12) and 13% (10-17) compared with 14% (11-16). The reduction of mortality risk in high-volume centres was even greater in patients without risk factors (48 vs 23%, p<0.001). INTERPRETATION: The normalised intrinsic mortality risk can be combined with the relative risk ratios of known risk factors to better estimate the mortality risk of a given procedure in a given patient. Centres can assess performance by removing potential bias of donor and recipient selection.

Adolescent↗
PubMed2000

Band 3 mutations, renal tubular acidosis and South-East Asian ovalocytosis in Malaysia and Papua New Guinea: loss of up to 95% band 3 transport in red cells.

We describe three mutations of the red-cell anion exchangerband 3 (AE1, SLC4A1) gene associated with distalrenal tubular acidosis (dRTA) in families from Malaysia and Papua NewGuinea: Gly(701)-->Asp (G701D), Ala(858)-->Asp(A858D) and deletion of Val(850) (DeltaV850). The mutationsA858D and DeltaV850 are novel; all three mutations seem to berestricted to South-East Asian populations. South-East Asianovalocytosis (SAO), resulting from the band 3 deletion of residues400-408, occurred in many of the families but did not itselfresult in dRTA. Compound heterozygotes of each of the dRTA mutationswith SAO all had dRTA, evidence of haemolytic anaemia and abnormal red-cell properties. The A858D mutation showed dominant inheritance and therecessive DeltaV850 and G701D mutations showed a pseudo-dominantphenotype when the transport-inactive SAO allele was also present. Red-cell and Xenopus oocyte expression studies showed that theDeltaV850 and A858D mutant proteins have greatly decreased aniontransport when present as compound heterozygotes (DeltaV850/A858D,DeltaV850/SAO or A858D/SAO). Red cells with A858D/SAO had only 3% ofthe SO(4)(2-) efflux of normal cells, thelowest anion transport activity so far reported for human red cells. The results suggest dRTA might arise by a different mechanism for eachmutation. We confirm that the G701D mutant protein has an absoluterequirement for glycophorin A for movement to the cell surface. Wesuggest that the dominant A858D mutant protein is possibly mis-targetedto an inappropriate plasma membrane domain in the renal tubular cell,and that the recessive DeltaV850 mutation might give dRTA because ofits decreased anion transport activity.

Acidosis, Renal Tubular↗
PubMed2000

Percutaneous portal vein thrombolysis and endovascular stent for management of posttransplant portal venous conduit thrombosis.

BACKGROUND: Thrombosis of a portal vein conduit after liver transplant is an uncommon clinical situation. Percutaneous thrombolytic therapy for this condition has not been widely described. METHODS: We describe a case of thrombosis of a portal vein (PV) conduit subsequent to orthotopic liver transplantation that was successfully treated by percutaneous portal vein thrombolysis by using tissue plasminogen activator, angioplasty, and endovascular stent placement. RESULTS: A satisfactory outcome was achieved with a patent portal vein, on ultrasound, at 8-month follow-up. CONCLUSION: A percutaneous transhepatic approach to treatment of thrombosis of a portal vein conduit appears to be a promising technique to use to avoid surgery, with good medium-term results.

Female↗
PubMed2000

Portal vein thrombosis in adults undergoing liver transplantation: risk factors, screening, management, and outcome.

BACKGROUND: Portal vein thrombosis (PVT) has been seen as an obstacle to liver transplantation (LTx). Recent data suggest that favorable results may be achieved in this group of patients but only limited information from small size series is available. The present study was conducted in an effort to review the surgical options in patients with PVT and to assess the impact of PVT on LTx outcome. Risk factors for PVT and the value of screening tools are also analyzed. METHODS: Adult LTx performed from 1987 through 1996 were reviewed. PVT was retrospectively graded according to the operative findings: grade 1: <50% PVT +/- minimal obstruction of the superior mesenteric vein (SMV); grade 2: grade 1 but >50% PVT; grade 3: complete PV and proximal SMV thrombosis; grade 4: complete PV and entire SMV thrombosis. RESULTS: Of 779 LTx, 63 had operatively confirmed PVT (8.1%): 24 had grade 1, 23 grade 2, 6 grade 3, and 10 grade 4 PVT. Being male, treatment for portal hypertension, Child-Pugh class C, and alcoholic liver disease were associated with PVT. Sensitivity of ultrasound (US) in detecting PVT increased with PVT grade and was 100% in grades 3-4. In patients with US-diagnosed PVT, an angiogram was performed and ruled out a false positive US diagnosis in 13%. In contrast with US, angiograms differentiated grade 1 from grade 2, and grade 3 from grade 4 PVT. Grade 1 and 2 PVT were managed by low dissection and/or a thrombectomy; in grade 3 the distal SMV was directly used as an inflow vessel, usually through an interposition donor iliac vein; in grade 4 a splanchnic tributary was used or a thrombectomy was attempted. Transfusion requirements in PVT patients (10 U) were higher than in non-PVT patients (5 U) (P<0.01). In-hospital mortality for PVT patients was 30% versus 12.4% in controls (P<0.01). Patients with PVT had more postoperative complications, renal failure, primary nonfunction, and PV rethrombosis. The overall actuarial 5-year patient survival rate in PVT patients (65.6%) was lower than in controls (76.3%; P=0.04). Patients with grade 1 PVT, however, had a 5-year survival rate (86%) identical to that of controls, whereas patients with grades 2, 3, and 4 PVT had reduced survival rates. The 5-year patient survival rate improved from the 1st to the 2nd era in non-PVT patients (from 72% to 83%; P<0.01), in grade 1 PVT (from 53% to 100%; P<0.01), and in grades 2 to 4 PVT (from 38% to 62%; P=0.11). CONCLUSIONS: The value of US diagnosis in patients with PVT depends on the PVT grade, and false negative diagnoses occur only in incomplete forms of PVT (grades 1-2). The degree of PVT dictates the surgical strategy to be used, thrombectomy/low dissection in grade 1-2, mesoportal jump graft in grade 3, and a splanchnic tributary in grade 4. Taken altogether, PVT patients undergo more difficult surgery, have more postoperative complications, have higher in-hospital mortality rates, and have reduced 5-year survival rates. Analysis by PVT grade, however, reveals that grade 1 PVT patients do as well as controls; only grades 2 to 4 PVT patients have poorer outcomes. With increased experience, results of LTx in PVT patients have improved and, even in severe forms of PVT, a 5-year survival rate >60% can now be achieved.

Adult↗
PubMed2000

Outcome of liver resection and transplantation for fibrolamellar hepatocellular carcinoma.

Fibrolamellar hepatocellular carcinoma (FL HCC) is an uncommon variant of hepatocellular carcinoma occurring usually in non-cirrhotic livers. Hepatic resection or transplantation offers the only chance of cure. We reviewed our experience of surgery for FL HCC from 1985-1998. Twenty patients with FL HCC (13 females and 7 males) median age 27 years (range 12-69) were treated either by hepatic resection [n = 11; extended right hepatectomy (5), extended left hepatectomy (1), right hemihepatectomy (2), left hemihepatectomy (2), left lateral segmentectomy (1)] or, if the disease was non-resectable, by transplantation (n = 9). The median follow up was 25 months (1-63). The prognostic factors analysed included size [less than 5 cm (3 patients), more than 5 cm (17 patients)], number [solitary (16 patients), multiple (4 patients)], capsular invasion (6 patients), vascular invasion (11 patients) and lymph node invasion (6 patients). The overall survival at 1, 3 and 5 years was 89.5, 75 and 50%, respectively. The liver resection survival was better than liver transplantation survival at 3 years 100 vs 76%, respectively (P < 0.025). Although all prognostic factors analysed did not show a significant difference, there is tendency that tumour stage was the most significant for prognosis. Most of the patients in this study are young and presented without specific symptoms, with normal liver function range and had no tumour marker to help in diagnosis. As a result most of our patients were diagnosed late. However the outcome of surgical intervention was favourable.

Adolescent↗
PubMed2000

Changing referral pattern of biliary injuries sustained during laparoscopic cholecystectomy.

SUMMARY: More patients with less severe type biliary injury are being referred earlier to a specialist hepatobiliary unit. Most patients still have ineffective corrective surgery before transfer. Presented in part to the European Congress of the International Hepato-Pancreatico-Biliary Association in Budapest, Hungary, May 1999 and published in abstract form as Digestive Surgery 1999; 16(Suppl 1): 32.

Bile Ducts↗
PubMed2000

Is it Kawasaki disease?

Atypical cases of KD are common (up to 10% of the total) and the diagnosis should be considered without the full complement of diagnostic criteria. The risk of coronary dilation is high if IVIG is not given. Administration of IVIG is effective at preventing aneurysms, if given early. The high-risk groups for coronary artery disease are infants younger than 6 months of age and older children with very high platelet counts, high ESR and fever persisting for more than 2 weeks.

Child↗
PubMed2000

A taste of honey.

Infantile botulism classically presents with a triad of clinical features: Bulbar palsies (slow/absent pupil response) Alert Absent fever Other common features are: Constipation, ptosis and poor feeding The diagnosis is a clinical one, confirmed by EMG and by testing stool for the organism, C. botulinum, or its toxin. Parents should be advised not to dip pacifiers in honey. In future Botulinum Immune Globulin may be available and should be considered if further trials are published showing benefit. Nosocomial infections, such as RSV, are important and should be carefully avoided, particularly in patients recovering from botulism.

Botulism↗
PubMed2000

A retrospective review of paediatric lymph node tuberculosis in Port Moresby, Papua New Guinea.

The study aimed to examine the perception that the relapse rate following standard short-course chemotherapy in children with lymph node tuberculosis is greater than in similarly treated children with pulmonary tuberculosis (TB). The treatment records, clinical data and results of investigations of 427 children treated for lymph node TB between 1989 and 1996 were analysed. The results and role of investigations are discussed. The relapse rate was compared with that of 892 children treated for pulmonary TB during the same period. The documented relapse rate for lymph node TB was 2.8% compared with 0.6% in pulmonary TB. This highly significant difference led to a prospective study of outcome of lymph node TB treatment in Port Moresby.

Biopsy, Needle↗
PubMed2000

Outcome of neonatal care in Port Moresby, Papua New Guinea: a 19-year review.

The effectiveness of changes in practice can only be determined by comparing outcome before and after their introduction. This report presents and discusses the neonatal statistics from Port Moresby General Hospital (PMGH) over the last 19 years and attempts to determine the effects of changes in practice introduced during the last year of the study period. Neonatal mortality rates have been very constant. However, the changes in practice--having all but the sickest babies nursed with their mothers and encouraging kangaroo care--together with strict adherence to breastfeeding policies, including the use of expressed breastmilk wherever possible, and the close involvement of the local breastfeeding support group in follow-up, appeared to have beneficial effects in reducing the length of stay and increasing the rate of weight gain in the very low birthweight babies.

Cause of Death↗
PubMed2000

Factors predicting perioperative cytokine response in patients undergoing liver transplantation.

OBJECTIVES: An exaggerated production of proinflammatory cytokines during liver transplantation stimulates the inflammatory process within the graft, and eventually promotes liver failure. This study was conducted to evaluate factors predicting perioperative response of proinflammatory cytokines during liver transplantation. DESIGN: Prospective, consecutive entry study of liver transplant candidates. SETTING: University hospital. PATIENTS: Thirty liver transplant recipients. INTERVENTIONS: Arterial blood samples were obtained perioperatively. MEASUREMENTS: Interleukin (IL)-1beta, IL-6, tumor necrosis factor-alpha were measured by ELISA. Endotoxin was determined by a chromogenic endotoxin-specific method. MAIN RESULTS: The peak concentrations of IL-1beta and IL-6 in the patients with complications were significantly higher than those in the patients without complications. The peak concentration of IL-1beta was significantly correlated with the level of bilirubin at admission and the intraoperative blood product requirement. The peak concentration of IL-6 was significantly correlated with the admission bilirubin and the intraoperative blood product requirement. A multivariate regression model revealed that the serum bilirubin and the intraoperative blood product requirement were the independent factors that influenced the peak concentration of IL-1beta or IL-6. The severely jaundiced patients had a significantly higher plasma concentration of endotoxin at the end of the anhepatic phase. In addition, there was a tendency for these patients to have a higher postoperative peak concentration of endotoxin. CONCLUSIONS: Serum level of bilirubin may be a potent preoperative factor influencing perioperative cytokine response in patients undergoing liver transplantation. An enhanced perioperative response of endotoxin seen in severely jaundiced patients suggests the clinical implication of endotoxin removal during the anhepatic phase in liver transplant surgery.

Adolescent↗
PubMed2000

Kangaroo care in Port Moresby, Papua New Guinea.

Kangaroo care is a simple and highly practical method of care of the low birthweight newborn which has been shown in some studies to significantly improve survival. We describe the introduction of 'kangaroo care' to the special care nursery at Port Moresby General Hospital, discuss the problems encountered and attempt to assess its impact in a 1-year retrospective study, during which it was associated with a reduction in hypothermia and an increased rate of weight gain.

Humans↗
PubMed1999

Poor outcome in patients with diabetes mellitus undergoing liver transplantation.

BACKGROUND: Relatively few studies have examined the influence of pretransplant diabetes on survival after an orthotopic liver transplant (OLT), and those published to date show only minor increases in infection rates among diabetics and no increase in mortality. METHODS: We examined the effect of diabetes mellitus on survival after OLT. 1005 adults underwent OLT between 1982 and May 1997. Seventy-eight patients with pretransplant diabetes mellitus (7.8% of all OLT, 38 insulin treated, 25 tablet treated, 15 diet controlled) were identified and compared with controls matched for age, sex, and date of first transplant and also with all nondiabetic adult liver recipients undergoing OLT during the same period. RESULTS: In patients undergoing OLT survival was worse in diabetics than in the comparison group (P=0.002) and vs. all adult nondiabetics undergoing (n=927) (P=0.004); in diabetics with alcoholic liver disease (ALD) vs. all nondiabetics with alcoholic liver disease (P= <0.0001); and in insulin-treated compared with non-insulin-treated diabetics (P=0.05). Multivariate analysis showed type of diabetes (P=0.001) and ALD (P=0.024) to be the most significant independent variables adversely affecting survival. Survival in diabetics undergoing OLT could be further stratified according to whether diabetics were insulin treated. CONCLUSIONS: Poorer outcome in the diabetics undergoing OLT, particularly in those with ALD, suggests the need for a more detailed pre-OLT assessment of these patients, particularly those with insulin and tablet controlled diabetes.

Adult↗