Venous thromboembolism during pregnancy and the post-partum period: incidence and risk factors in a large Victorian health service

BACKGROUND: There is a strong recommendation for post-partum thromboprophylaxis following emergency caesarean sections, particularly in overweight women, and following prolonged labour. AIMS: To analyse the incidence and epidemiological factors associated with antepartum and post-partum venous thromboembolism in a large Victorian health service. METHODS: A retrospective study of all 6987 women delivering at Ballarat Health Services between March 1999 and June 2006. Case notes of women with confirmed venous thromboembolism during this period were subjected to detailed analysis. The data were analysed for possible risk factors, the timing of thromboembolism in relation to the pregnancy and any correlation with thromboprophylaxis, if administered. Results: The rate of venous thromboembolism was 1.14 per 1000 deliveries, with risk factors of age > 30 (100%), obesity (75%), previous history of thromboembolism (62.5%) and caesarean section (37.5%). Majority of cases were diagnosed in first trimester (62.5%), and in the right lower limb (75%). None of the patients had been given thromboprophylaxis. CONCLUSION: While the incidence and risk factors were similar to those generally quoted, a much higher incidence was found in early pregnancy, and in the right lower limb. The importance of meticulous screening for risk factors in early pregnancy cannot be overemphasised.     

Changing bacteriological patterns in neonatal septicaemia

The various organisms responsible for septicaemia and their changing sensitivity patterns were studied. The incidence of neonatal septicaemia was 26·3%. Group I comprised of 242 cases in 1981–1982 and group II 150 cases in 1984. Gram negative organisms were isolated in the majority of blood cultures, 52·5% and 43·4% in group I and II respectively. Klebsiella though showing a fall in incidence, still remained the commonest Gram negative organism isolated. The incidence of E. coli, pseudomonas and staphylococcal infections also doubled in group II as compared to group I. An alarming trend was the increasing resistance of the isolates to commonly used penicillins and aminoglycosides. The incidence of organisms resistant to all commonly used antibiotics has also increased from 13% to about 40%. This problem could be combated by rotating the commonly used antibiotic combinations, as well as discouraging the unnecessary use of antibiotics.     

Maximizing ureteroscope deflection: "play it straight"

We studied simple maneuvers to optimize active deflection of the flexible ureteroscope. Up to 61 degrees of active deflection is lost if the ureteroscope is not kept in a straight alignment. Holding the ureteroscope taut, placing a super-stiff guidewire in the working channel, or using an access sheath maximizes active deflection.     

Urology practice patterns after residency training in laparoscopy

PURPOSE: Laparoscopic training has been incorporated into many urology residency programs. Although the impact of laparoscopic training courses has been examined, the impact of residency training in laparoscopy on subsequent urology practice patterns has not been assessed. MATERIALS AND METHODS: Urologists completing their residency from 1977 through 1999 at Tulane University and the University of California-San Diego were sent anonymous questionnaires in September 2000. The questionnaires evaluated practice demographics, operative experience in laparoscopy during residency, and the role of laparoscopy in the urologist's current practice. Factors impacting the decision to perform or not perform laparoscopy were evaluated. RESULTS: Sixty-one former residents (67%) responded to the questionnaire. Urologists were more likely to perform laparoscopic procedures if they had been trained during their residency (69%) than if they had no experience during residency (34%; p < 0.025). Intensity of laparoscopic experience in residency did not appear to correlate with ongoing practice, with 73% of residents having <15 cases during residency training continuing to perform laparoscopy compared with 67% of residents doing 15 to 80 laparoscopic cases. Urologists who had been trained in laparoscopy during residency cited the need for more training (47%) and inadequate case volume (47%) as reasons for not currently performing laparoscopy. Among those who had received residency training, the most common reasons given were inadequate case volume (61%) and increased operative time (57%). CONCLUSIONS: This survey suggests that laparoscopic procedures are more likely to be performed by physicians who have received training during residency. As the number of urologists who have been trained in laparoscopy during residency increases, shifts in practice patterns will continue to evolve, along with advances in urologic laparoscopy.     

Hepatocyte growth factor induces Wnt-independent nuclear translocation of beta-catenin after Met-beta-catenin dissociation in hepatocytes

Hepatocyte growth factor (HGF) and Wnt signaling pathways have been shown to be important in embryogenesis and carcinogenesis. The aim of this study was to elucidate the mechanism of functional similarities observed in the two pathways. We used normal rat liver, primary hepatocyte cultures and a dominant-negative Met expression system to study the effect of HGF on Wnt pathway components. We demonstrate novel association of beta-catenin and Met, a tyrosine kinase receptor of HGF, at the inner surface of the hepatocyte membrane. HGF induces dose-dependent nuclear translocation of beta-catenin in primary hepatocyte cultures that is Wnt independent. The source of beta-catenin for translocation in hepatocytes is the Met-beta-catenin complex, which appears to be independent of the E-cadherin-beta-catenin complex. To test the functionality of this association, we used a dominant-negative Met expression system that expresses only the extracellular and transmembrane regions of the beta-subunit of Met. A loss of Met-beta-catenin association resulted in abrogation of nuclear translocation of beta-catenin upon HGF stimulation. This event is tyrosine phosphorylation dependent, and the association of Met and beta-catenin is crucial for this event. We conclude that the HGF causes similar redistribution of beta-catenin as Wnt-1 in the hepatocytes and that this effect is attributable to subcellular association of Met and beta-catenin. The intracellular kinase domain of Met is essential for tyrosine phosphorylation and nuclear translocation of beta-catenin. Part of the multifunctionality of HGF might be attributable to nuclear beta-catenin and the resulting target gene expression.     

Radial dilation of ureteral balloons: comparative in vitro analysis

BACKGROUND AND PURPOSE: The dynamics of ureteral balloon expansion may differ with increasing extrinsic compressive forces and inflation pressures. This study compared the ability of ureteral balloons to expand under different conditions. MATERIALS AND METHODS: The balloons tested were the Cook Accent, Ascend, Ascend AQ, and Pursuit; the Bard 195503 and UroForce; and the Boston Scientific Microvasive UroMax Ultra. When available, multiple balloon diameters and lengths were tested. With a guidewire in place, the balloon tip was secured by elevated vise grips on either side of the balloon. A string was wrapped around the balloon center once, and incremental increases in load were added (2 g, 42 g, 82 g, 122 g) to represent increasing extrinsic compression. The balloon was inflated with contrast medium, and circumference changes were measured at increments of 2 atm up to burst pressure. Balloons were tested in triplicate for each weight. RESULTS: The majority of the balloons were unable to reach 90% of their expected diameter with larger constrictive loads (122 g) at low inflation pressure (4 atm). The only balloons that achieved a diameter at 4 atm that was at least 90% of the expected diameter with a coefficient of variance (CV) of <10% at all radial loads were the Pursuit 6 mm x 4 cm (98.2 +/- 2.2%; CV 7.88%), UroMax Ultra 7 mm x 4 cm (97.5 +/- 1.4%; CV 5.94%), and the UroMax Ultra 7 mm x 6 cm (101 x 1.2%; CV 7.67%). At inflation burst pressure, the balloons able to maintain a diameter at or above 100% of expected with a CV of <5% at burst pressure were the Ascend AQ 4 mm x 4 cm (116 +/- 1.0%; CV 3.34%) and the Pursuit 6 mm x 4 cm (108 +/- 2.0%; CV 4.53%). CONCLUSION: Reaching maximum inflation diameter at low pressures in the face of increasing extrinsic compression may help minimize the risk of ureteral injury. Reliable expansion to maximum diameter even with higher extrinsic compressive forces is another important characteristic of ureteral balloons. Balloon material, configuration, and dimensions may contribute to differences in dilation properties.     

Temperature activated deflection of a novel ureteroscopic laser fiber sheath

PURPOSE: Loss of active deflection with insertion of a holmium laser fiber can significantly decrease the efficacy of intrarenal flexible ureteroscopy. We evaluated the impact of inserting a novel, temperature activated, deflectable laser sheath on active deflection and flow rates. METHODS AND MATERIALS: Active deflection of 5 flexible ureteroscopes was measured with an empty channel and following separate insertions of 2, 272 mum holmium fibers. Insertion of the same fibers was then repeated through a proprietary, temperature activated, coiling nitinol sheath. Active deflection of the sheath following insertion into the working channel was achieved by a rapid flush of 10 cc hot water (60C) through the irrigation side port. Release of active deflection was obtained by repeating this maneuver with cold water (15C). Degrees of deflection were measured in triplicate. Flow rates were measured at 100 cm H2O pressure. RESULTS: Active deflection with an empty working channel decreased significantly with insertion of the 2 laser fibers (12 to 32 degrees). Insertion of the laser fiber through the nitinol sheath followed by temperature activation of the sheath maximized active deflection beyond baseline measures with the laser fibers by up to 60 degrees. Flow rates in all ureteroscopes decreased significantly with the use of the Powerflex sheath (Optical Integrity, Panama City, Florida) but it remained above 12 ml per minute in all ureteroscopes. CONCLUSIONS: A temperature activated, deflectable nitinol sheath facilitates active deflection with a 272 mum holmium laser fiber in the working channel of the flexible ureteroscope, suggesting strong potential for clinical evaluation.