Percutaneous cholecystography in children

Percutaneous cholecystography was performed on 13 children who had biliary system abnormalities: two had biliary hypoplasia, five had sclerosing cholangitis, three had cirrhosis, two had distal choledochal obstruction, and one had an obstructed portoenterostomy. In 12 patients transcholecystic cholangiography showed, without significant complications, the intra-and extrahepatic bile ducts. In one patient with primary sclerosing cholangitis, the intrahepatic bile ducts were not opacified satisfactorily; dilatation of the gallbladder required surgical drainage. The transcholecystic technique is indicated when the intrahepatic bile ducts are either mildly dilated or not dilated.     

Aetiological Rôle Of Cerebral Blood-Flow Alterations In Development And Extension Of Peri-Intraventricular Haemorrhage

The aetiology and extension of peri-intraventricular haemorrhage (PIVH) are thought to be related to cerebral blood-flow alterations, and especially to increased cerebral blood-flow and fluctuating velocity of blood-flow. Using transcutaneous Doppler technique, the authors investigated cerebral blood-flow in 60 infants with gestations of less than 34 weeks. Pulsatility index (PI) and area under the velocity curve (AUVC) of the anterior cerebral arteries (ACA) were used as qualitative measures of cerebral blood-flow, and the coefficient of variation of PI and AUVC as indicators of fluctuations in blood-flow velocity. A reasonable correlation was found between PI and AUVC and their coefficients of variation in the ACA. First onset of PIVH was related to fluctuating blood-flow velocity, and extension of PIVH with both increased velocity (indicating increased blood-flow) and fluctuating velocity. Increased cerebral blood-flow and its fluctuating pattern were positively correlated with arterial carbon dioxide tension.     

Detection of base damage in DNA in human blood exposed to ionizing radiation at biologically relevant doses.

The alkaline elution technique for the detection of DNA damage has been adapted to allow application on unlabelled blood cells. Both the induction and subsequent repair have been studied of two classes of DNA damage, viz, single-strand breaks and base damage recognized by the gamma-endonuclease activity in a cell-free extract of Micrococcus luteus bacteria. The high sensitivity of the assay permitted the measurement of induction and repair of base damage after in vitro exposure of full blood under aerobic conditions to biologically relevant doses of gamma-rays (1.5-4.5 Gy). After a radiation dose of 3 Gy about 50% of the base damage was removed within 1.5 h of repair. Base damage could still be detected at 24 h after exposure to 15 Gy.     

Systolic and diastolic pressure-volume relationships during cardiac surgery

Seven patients undergoing elective coronary artery bypass surgery were studied to assess left ventricular (LV) performance by pressure-volume loops. LV pressure was measured by micromanometry and instantaneous LV volume by a conductance catheter. Continuous pressure-volume relationships were determined during preload reduction before and after cardiopulmonary bypass (CPB). End-systolic elastance (Ees), as the slope of the end-systolic pressure-volume relationship (ESPVR), and diastolic elastance (Ed) were calculated from these interventions. Changes in position of the Ees were assessed at V75, the value of LV end-systolic volume at 75 mm Hg of LV pressure. From pre-CPB to post-CPB, Ees increased in three patients with a decrease of V75 in two patients, and Ees decreased in four patients with a concomitant increase in V75. Ed increased significantly (P less than 0.01) following CPB, demonstrating a decrease of ventricular distensibility. It is concluded that continuous measurement of LV pressure-volume relationships using the conductance catheter is feasible and may be a useful tool to estimate LV performance during cardiac surgery.     

What is a safe waiting time for coronary artery bypass surgery?

To determine the factors that influenced doctors' prioritization and decisions on safe waiting time for coronary artery bypass surgery, 50 'paper patients', based on a random sample of cases who actually had surgery, were assessed by 33 clinicians. We used linear regression models to reflect the impact of clinical and non-clinical 'cues' on safe waiting time and priority decisions. The benefits of surgery tended to be over-estimated. For example, the average perceived gain in life expectancy for patients with left main-stem disease was 6.74 years. However, models incorporating only the perceptions of benefit as independent variables (i.e. the anticipated symptom reduction, MI risk reduction and life expectancy extension), had only modest explanatory power (mean R2 was 0.55 for safe waiting time, and 0.56 for priority decisions). Models which incorporated perceptions of benefit and the cases' clinical and non-clinical characteristics had generally much higher explanatory power (mean R2, 0.83 and 0.86, respectively). Lifestyle and demographic variables had much less impact on the doctors' judgements than the major clinical cues of angina severity and left main-stem stenosis. Demographic and lifestyle cues had different impacts on safe waiting time and priority for about 25% of doctors.      

Thrombosis in inflammatory bowel disease: clinical setting, procoagulant profile and factor V Leiden

Patients with inflammatory bowel disease have an increased frequency of thromboembolism, and microvascular thrombosis has been proposed as a contributory pathogenic factor. The mechanism of enhanced procoagulant activity is not understood. We examined the clinical setting of thromboembolic events in 52 patients with Crohn's disease or ulcerative colitis, and assessed the procoagulant laboratory profile, including Factor V Leiden, in a subset of 20 patients to identify procoagulant risk factors. Patients who developed thrombosis tended to be young; 60% of thrombotic events occurred in patients under 50 years. Multiple thromboembolic episodes occurred in 13% and unusual sites of thrombosis (e.g. intracardiac, cerebral, inominate veins) in 11%. No risk factor was identifiable in 52% of cases and two-thirds of thromboses occurred in an out-patient setting. The mortality rate was 8%. Evidence for inflammatory disease activity was found in only 45% of patients with ulcerative colitis at the time of the thromboembolic event, in contrast to 89% of those with Crohn's disease. Assays for specific coagulation defects were negative in all cases tested (protein S, C were normal in 17/17; anti-thrombin III, anti-phospholipid antibodies and activated protein C resistance were negative in 20/20, and only 1/20 patients was found to be heterozygous for Factor V leiden. Thrombosis in inflammatory bowel disease is important because it occurs in a young population, often in unusual sites, and has a high mortality. The development of thrombosis is related to active inflammatory disease in most patients with Crohn's disease but apparently not in those with ulcerative colitis. Since approximately half of the patients had no other identifiable risk factor, there remains a substantial group of patients with IBD who develop thrombosis for unknown reasons.