Observation of the onset of a blue jet into the stratosphere.

Blue jets are lightning-like, atmospheric electric discharges of several hundred millisecond duration that fan into cones as they propagate from the top of thunderclouds into the stratosphere1. They are thought to initiate in an electric breakdown between the positively charged upper region of a cloud and a layer of negative charge at the cloud boundary and in the air above. The breakdown forms a leader that transitions into streamers2 when propagating upwards3. However, the properties of the leader, and the altitude to which it extends above the clouds, are not well characterized4. Blue millisecond flashes in cloud tops5,6 have previously been associated with narrow bipolar events7,8, which are 10- to 30-microsecond pulses in wideband electric field records, accompanied by bursts of intense radiation at 3 to 300 megahertz from discharges with short (inferred) channel lengths (less than one kilometre)9-11. Here we report spectral measurements from the International Space Station, which offers an unimpeded view of thunderclouds, with 10-microsecond temporal resolution. We observe five intense, approximately 10-microsecond blue flashes from a thunderstorm cell. One flash initiates a pulsating blue jet to the stratopause (the interface between the stratosphere and the ionosphere). The observed flashes were accompanied by 'elves'12 in the ionosphere. Emissions from lightning leaders in the red spectral band are faint and localized, suggesting that the flashes and the jet are streamer ionization waves, and that the leader elements at their origin are short and localized. We propose that the microsecond flashes are the optical equivalent of negative narrow bipolar events observed in radio waves. These are known to initiate lightning within the cloud and to the ground, and blue lightning into the stratosphere, as reported here.

A terrestrial gamma-ray flash and ionospheric ultraviolet emissions powered by lightning.

Terrestrial gamma-ray flashes (TGFs) are transient gamma-ray emissions from thunderstorms, generated by electrons accelerated to relativistic energies in electric fields. Elves are ultraviolet and optical emissions excited in the lower ionosphere by electromagnetic waves radiated from lightning current pulses. We observed a TGF and an associated elve using the Atmosphere-Space Interactions Monitor on the International Space Station. The TGF occurred at the onset of a lightning current pulse that generated an elve, in the early stage of a lightning flash. Our measurements suggest that the current onset is fast and has a high amplitude-a prerequisite for elves-and that the TGF is generated in the electric fields associated with the lightning leader.

EPC/HPSG evidence-based guidelines for the management of pediatric pancreatitis.

BACKGROUND: Pediatric pancreatitis is an underdiagnosed disease with variable etiology. In the past 10-15 years the incidence of pediatric pancreatitis has increased, it is now 3.6-13.3 cases per 100,000 children. Up-to-date evidence based management guidelines are lacking for the pediatric pancreatitis. The European Pancreatic Club, in collaboration with the Hungarian Pancreatic Study Group organized a consensus guideline meeting on the diagnosis and management of pancreatitis in the pediatric population. METHODS: Pediatric Pancreatitis was divided into three main clinical categories: acute pancreatitis, acute recurrent pancreatitis and chronic pancreatitis. Fifteen relevant topics (acute pancreatitis: diagnosis; etiology; prognosis; imaging; complications; therapy; biliary tract management; acute recurrent pancreatitis: diagnosis; chronic pancreatitis: diagnosis, etiology, treatment, imaging, intervention, pain, complications; enzyme replacement) were defined. Ten experts from the USA and Europe reviewed and summarized the available literature. Evidence was classified according to the GRADE classification system. RESULTS: Within fifteen topics, forty-seven relevant clinical questions were defined. The draft of the updated guideline was presented and discussed at the consensus meeting held during the 49th Meeting of European Pancreatic Club, in Budapest, on July 1, 2017. CONCLUSIONS: These evidence-based guidelines provides the current state of the art of the diagnosis and management of pediatric pancreatitis.

Gastrointestinal quality-of-life after cholecystectomy: indication predicts gastrointestinal symptoms and abdominal pain.

BACKGROUND: Despite the fact that cholecystectomy is a common surgical procedure, the impact on long-term gastrointestinal quality of life is not fully known. METHODS: All surgical procedures for gallstone disease performed at Mora County Hospital, Sweden, between 2 January 2002 and 2 January 2005, were registered on a standard database form. In 2007, all patients under the age of 80 years at follow-up were requested to fill in a form containing the Gastrointestinal Quality-of-Life Index (GIQLI) questionnaire and a number of additional questions. The outcome was analysed with respect to age, gender, smoking, surgical technique, and original indication for cholecystectomy. RESULTS: A total of 627 patients (447 women, 180 men) underwent cholecystectomy, including laparoscopic cholecystectomy (N = 524), laparoscopic cholecystectomy converted to open cholecystectomy (N = 43), and open cholecystectomy (N = 60). The mean time between cholecystectomy and follow-up with the questionnaire was 49 months. The participation rate was 79 %. Using multivariate analysis in the form of generalised linear modelling, the original indication for cholecystectomy in combination with gender (p = 0.0042) was found to predict the GIQLI score. Female gender in combination with biliary colic as indication for cholecystectomy correlated with low GIQLI scores. Female gender also correlated with a higher risk for pain in the right upper abdominal quadrant after cholecystectomy (p = 0.028). CONCLUSIONS: We found the original indication for cholecystectomy, together with gender, to predict gastrointestinal symptoms and abdominal pain after cholecystectomy. Careful evaluation of symptoms is important before planning elective cholecystectomy.

Monitoring dominant strictures in primary sclerosing cholangitis with brush cytology and FDG-PET.

BACKGROUND & AIMS: Despite a high risk of cholangiocellular adenocarcinoma (CCA) it is unclear how surveillance of patients with primary sclerosing cholangitis (PSC) should be performed. METHODS: We evaluated a follow-up algorithm of brush cytology and positron emission tomography/computed tomography with [(18)F] fluorodeoxyglucose ([(18)F]FDG-PET/CT), measured as maximum standardized uptake values, normalized to the liver background (SUVmax/liver) at 180 min, in PSC patients with dominant bile duct strictures. RESULTS: Brush cytology with high grade dysplasia (HGD) was detected in 12/70 patients (17%), yielding a diagnostic sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 56%, 89%, 75%, and 88%, respectively. Preemptive liver transplantations due to repeated HGD before manifest CCA were performed in six patients. Receiver operating characteristic (ROC) analysis of [(18)F]FDG uptake showed that a SUVmax/liver quotient of 3.3 was able to discriminate between CCA and non-malignant disease with a sensitivity, specificity, PPV and NPV for CCA of 89%, 92%, 62%, 98%, respectively. A SUVmax/liver >3.3 detected CCA in 8/9 patients whereas a quotient <2.4 excluded CCA. Combining brush cytology and quantitative [(18)F]FDG-PET/CT yielded a sensitivity for HGD and/or CCA of 100% and a specificity of 88%. CONCLUSION: Early detection of HGD before manifest CCA is feasible with repeated brush cytology and may allow for preemptive liver transplantation. [(18)F]FDG-PET/CT has a high sensitivity for manifest CCA and a negative scan indicates a non-malignant state of the disease. Brush cytology and [(18)F]FDG-PET/CT are complementary in monitoring and managing PSC patients with dominant strictures.

Biliary microflora in patients undergoing cholecystectomy.

BACKGROUND: The management of acute cholecystitis requires a sound knowledge of the biliary microflora. METHODS: Bile samples were taken for culture according to a standard routine during all cholecystectomies performed from April 2007 to February 2009 in the Department of Surgery at Enköping Hospital. The use of antibiotics within the 3-mo period before surgery, indication for surgery, prophylactic antibiotics, and post-operative complications were recorded prospectively. RESULTS: Altogether, 246 procedures were performed during the study period, of which 149 (62%) were done on women. The mean (±SD) age of the study subjects was 49±16 y. Bacterial growth was seen in cultures from 34 (14%) of the subjects. The mean age of subjects with positive cultures was 64 y and that of subjects with negative cultures was 47 y (p<0.001). Positive culture was seen in 16 (31%) of the 51 patients who underwent operations for acute cholecystitis, whereas positive cultures were obtained in 18 of 195 patients without acute cholecystitis (9%) (p<0.001). Resistance to ampicillin was recorded in three of 34 (9%) of the cultures with bacterial growth, to co-trimoxazole in one of the 34 (3%) cultures, to fluoroquinolones in one of the 34 (3%) cultures, and to cephalosporins in one of the 34 (3%) cultures. Resistance to piperacillin-tazobactam was not observed in any of the cultures. In multivariable logistic regression analysis, a positive culture was the only factor significantly associated with risk for post-operative infectious complications (p<0.05). DISCUSSION: Bacterial growth in the bile is observed more often in patients undergoing surgery for acute cholecystitis. The microflora of the bile is probably important for the outcome of surgery, but further studies are required for assessing the effectiveness of measures for preventing infectious post-operative complications.

Effectiveness of antibiotic prophylaxis in cholecystectomy: a prospective population-based study of 1171 cholecystectomies.

BACKGROUND: The aim of this study was to assess the benefit from antibiotic prophylaxis (AP) during cholecystectomy in a population-based cohort study. METHODS: All cholecystectomies performed in Uppsala County, 2003-2005, were registered prospectively according to a standardized protocol. High-risk procedures (HP) were defined as operations for acute cholecystitis and procedures including exploration of the common bile duct. Infections requiring surgical or percutaneous drainage and non-surgical infections that prolonged hospital stay were defined as major infectious complications (IC). RESULTS: Altogether 1171 patients underwent cholecystectomy. AP was given to 130 of 867 (15%) of the patients undergoing low-risk procedures (LP) and 205 of 304 (67%) of those undergoing H-R P. Major IC were seen in 6 of 205 (3%) of the patients undergoing H-R P with AP and 1 of 99 of the patients undergoing H-R P without AP. No major IC was seen after L-R P. Minor IC were seen after 5 of 205 (2%) HP with AP, 1 of 99 (1%) HP without AP, 0 of 130 (0%) LP with AP, and 2 of 737 (0.3%) LP without AP. In univariate logistic analysis, the overall risk for IC was found to be higher with AP (p < 0.05), but the increase did not remain significant if adjusting for age, gender, ASA class, H-R P/L-R P and surgical approach or limiting the analysis to major IC. CONCLUSION: There is no benefit from AP in uncomplicated procedures. The effectiveness of antibiotic prophylaxis in complicated cholecystectomy must be evaluated in randomized controlled trials.

Registration of health-related quality of life in a cohort of patients undergoing cholecystectomy.

Background. Assessment of gallstone surgery's impact on quality of life (QoL) requires a reliable instrument with sufficient responsiveness. The instrument should also enable estimation of each individual's expected condition in an unaffected state. Materials and Methods. The Swedish Register for Gallstone Surgery and ERCP (GallRiks) registers indications, complications, results, and QoL-outcome of gallstone surgery. In 2008, 68 hospitals were registered in GallRiks. Between 2007 and 2008, SF-36 (a short form health survey) was filled in 1-2 weeks pre- and 6-9 months postoperatively at five of the units. Expected scores were determined from an age- and gender-matched Swedish population (AGMSP). Results. Of the 330 patients, 212 responded to SF36 pre- and postoperatively (RR = 64%; 212/330). Standardized response means ranged from 0.20 to 0.93 for the SF-36 subscores. Highest responsiveness was seen for bodily pain. Preoperatively, all subscores were significantly lower than in the AGMSP (all P < .05). Six months postoperatively, there was no significant difference between any of the observed and expected quality of life subscales. Conclusion. SF-36 is a useful instrument for measuring the impact of gallstone surgery on QoL. The postinterventional health status equalled or even exceeded the AGMSP for all subscales.

Are liver function tests, pancreatitis and cholecystitis predictors of common bile duct stones? Results of a prospective, population-based, cohort study of 1171 patients undergoing cholecystectomy.

OBJECTIVE: The purpose of this study was to explore the accuracy of elevated liver function values, age, gender, pancreatitis and cholecystitis as predictors of common bile duct stones (CBDS). METHODS: All patients operated on for gallstone disease over a period of 3 years in a Swedish county of 302,564 citizens were registered prospectively. Intraoperative cholangiography (IOC) was used to detect CBDS. RESULTS: A total of 1171 patients were registered; 95% of these patients underwent IOC. Common bile duct stones were found in 42% of patients with elevated liver function values, 20% of patients with a history of pancreatitis and 9% of patients with cholecystitis. The presence of CBDS was significantly predicted by elevated liver function values, but not by age, gender, history of acute pancreatitis or cholecystitis. A total of 93% of patients with normal liver function tests had a normal IOC. The best agreement between elevated liver function values and CBDS was seen in patients undergoing elective surgery without a history of acute pancreatitis or cholecystitis. CONCLUSIONS: Although alkaline phosphatase (ALP) and bilirubin levels represented the most reliable predictors of CBDS, false positive and false negative values were common, especially in patients with a history of cholecystitis or pancreatitis, which indicates that other mechanisms were responsible for elevated liver function values in these patients.

Associations between fungal species and water-damaged building materials.

Fungal growth in damp or water-damaged buildings worldwide is an increasing problem, which has adverse effects on both the occupants and the buildings. Air sampling alone in moldy buildings does not reveal the full diversity of fungal species growing on building materials. One aim of this study was to estimate the qualitative and quantitative diversity of fungi growing on damp or water-damaged building materials. Another was to determine if associations exist between the most commonly found fungal species and different types of materials. More than 5,300 surface samples were taken by means of V8 contact plates from materials with visible fungal growth. Fungal identifications and information on building material components were analyzed using multivariate statistic methods to determine associations between fungi and material components. The results confirmed that Penicillium chrysogenum and Aspergillus versicolor are the most common fungal species in water-damaged buildings. The results also showed Chaetomium spp., Acremonium spp., and Ulocladium spp. to be very common on damp building materials. Analyses show that associated mycobiotas exist on different building materials. Associations were found between (i) Acremonium spp., Penicillium chrysogenum, Stachybotrys spp., Ulocladium spp., and gypsum and wallpaper, (ii) Arthrinium phaeospermum, Aureobasidium pullulans, Cladosporium herbarum, Trichoderma spp., yeasts, and different types of wood and plywood, and (iii) Aspergillus fumigatus, Aspergillus melleus, Aspergillus niger, Aspergillus ochraceus, Chaetomium spp., Mucor racemosus, Mucor spinosus, and concrete and other floor-related materials. These results can be used to develop new and resistant building materials and relevant allergen extracts and to help focus research on relevant mycotoxins, microbial volatile organic compounds (MVOCs), and microparticles released into the indoor environment.

Psychiatric caseness is a marker of major depressive episode in general practice.

OBJECTIVE: Screening for a major depressive episode (MDE) in high-risk groups of patients within the primary care setting has been suggested by several Central Health Organizations. The objective of this study was to investigate whether patients rated as "psychiatric cases" by their general practitioner (GP) were likely to suffer from MDE and therefore qualified for systematic diagnostic screening. DESIGN: Cross-sectional survey of primary care patients assessed through depression screening questionnaires and GP consultations. SETTING: A total of 676 general practices in Denmark, Finland, Norway, and Sweden. Subjects. A total of 8879 unselected primary care patients. MAIN OUTCOME MEASURES: sensitivity, specificity, and Youden Index of the GPs' diagnoses of depression and psychiatric caseness versus patients' MDE status. RESULTS: The proportion of primary care patients receiving a false-positive diagnosis of depression by their GP ranged from 12.4% to 25.2% depending on country. The corresponding numbers for the false-negative diagnoses were 0.9-2.5% [corrected]. Among patients with MDE, GPs recognize the disease in 56-75% of cases. However, GPs recognize as many as 79-92% of patients with MDE as "psychiatric cases". CONCLUSIONS: This report confirms that misclassifications of MDE are common in the primary care setting. In addition, it shows that psychiatric caseness is a valid marker for the presence of MDE in primary care patients. This relationship should be considered in future screening recommendations.

Validation of Gastrointestinal Quality of Life Index in Swedish for assessing the impact of gallstones on health-related quality of life.

OBJECTIVE: The aim of the present study was to validate a Swedish translation of the Gastrointestinal Quality of Life Index (GIQLI) questionnaire in patients with gallstone disease. METHODS: Sensitivity to change, internal consistency, and test-retest stability were tested in 187 consecutive patients who underwent planned cholecystectomy. Construct validity was assessed by comparing the GIQLI score with the bodily pain scale of SF-36 and four single-item questions in a separate group of 104 patients. RESULTS: A significant increase in all five domains as well as in the overall GIQLI score 6 months after surgery (all P < 0.05) was seen. All five domains correlated significantly with other measures of gallstone-related symptoms except one single-item question. Intraclass correlations ranged from 0.62 to 0.87. Cronbach's alpha ranged from 0.77 to 0.89. CONCLUSION: The Swedish translation of GIQLI has a high validity and reliability for assessing the impact of gallstones on quality of life.

Primary patency of percutaneously inserted self-expanding metallic stents in patients with malignant biliary obstruction.

BACKGROUND: Effective bile duct drainage is crucial to the health-related quality of life of patients with jaundice caused by obstruction of the bile duct by inoperable malignant tumours. METHODS: All patients who were treated at Uppsala University Hospital, Sweden with percutaneous stenting between 2000 and 2005 were identified retrospectively. Data on the location of the obstruction and type of stent used, date and cause of death and date of stent failure were abstracted from the patients' notes. Stent patency was defined as the duration from the insertion of the stent to the date of failure. In cases in which the cause of death was directly related to failure of the stent, the date of death was defined as the patency endpoint. RESULTS: A total of 64 patients (34 women, 30 men) were identified. Their mean age was 71 years (standard deviation 11 years). The median length of patency was 11.4 months. Stent diameter >10 mm and distal stricture were found to be associated with significantly longer patency time in univariate Cox proportional hazard analysis. In multivariate Cox proportional hazard analysis, only location of the stricture was found to be independently and significantly associated with patency time. DISCUSSION: Percutaneous stenting is a good alternative for patients with obstructive jaundice and a life expectancy < or = 1 year. It may give instant relief from the symptoms associated with jaundice. Patency time may be prolonged by using stents with a diameter > or = 10 mm. However, patency time was found to be lower for hilar tumours.

How reliable is intraoperative cholangiography as a method for detecting common bile duct stones? : A prospective population-based study on 1171 patients.

BACKGROUND: Although intraoperative cholangiography (IOC) is a widely used method for detecting common bile duct stones (CBDS), its accuracy has not been fully evaluated in large nonselected patient samples. The purpose of this study was to assess the sensitivity, specificity and predictive value of dynamic IOC regarding its ability to diagnose CBDS in a population-based setting, and to assess the morbidity associated with the investigation. METHODS: All patients operated on for gallstone disease between 2003 and 2005 in the county of Uppsala in Sweden, a county with a population of 302,000 in December 2004, were registered prospectively. The outcome of cholangiography was validated against the postoperative clinical course. RESULTS: 1171 patients were registered, and among these IOC was performed in 1117 patients (95%). Common bile duct stones were found in 134 patients (11%). One perforation of the common bile duct caused by the IOC catheter was recorded. Sensitivity was 97%, specificity 99%, negative predictive value 99%, positive predictive value 95%, and overall accuracy 99%. In 7 of the 134 cases where IOC indicated CBDS, no stones could be verified on exploration. In 4 of the 979 cases where IOC was normal, the clinical course indicated overlooked CBDS. CONCLUSION: Intraoperative cholangiography is a safe and accurate method for detecting common bile duct stones.

Low recurrence rate after laparoscopic (TEP) and open (Lichtenstein) inguinal hernia repair: a randomized, multicenter trial with 5-year follow-up.

OBJECTIVES: To compare a laparoscopic (totally extraperitoneal patch (TEP)) and an open technique (Lichtenstein) for inguinal hernia repair regarding recurrence rate and possible risk factors for recurrence. SUMMARY BACKGROUND DATA: Laparoscopic hernia repair has been introduced as an alternative to open repair. Short-term follow-up suggests benefits for those patients operated with a laparoscopic approach compared with open techniques; ie, less postoperative pain and a shorter convalescence period. Long-term results, however, are less well known. METHODS: The study was conducted as a multicenter randomized trial with a 5-year follow-up. A total of 1512 men aged 30 to 70 years, with a primary unilateral inguinal hernia, were randomized to either TEP or Lichtenstein repair. RESULTS: Overall, 665 patients in the TEP group and 705 patients in the Lichtenstein group were evaluable. The cumulative recurrence rate was 3.5% in the TEP group and 1.2% in the Lichtenstein group (P = 0.008). Test for heterogeneity revealed significant differences between individual surgeons. The exclusion of 1 surgeon, who was responsible for 33% (7 of 21) of all recurrences in the TEP group, lowered the cumulative recurrence rate to 2.4% in this group, which was not statistically different from that of the Lichtenstein group. CONCLUSIONS: The recurrence rate for both TEP and Lichtenstein repair was low. A higher cumulative recurrence rate in the TEP group was seen at 5 years. Further analysis revealed that this could be attributable to incorrect surgical technique.

TPS, CA 19-9, VEGF-A, and CEA as diagnostic and prognostic factors in patients with mass lesions in the pancreatic head.

INTRODUCTION: Although numerous tumour markers are available for periampullary tumours, including pancreatic cancer, their specificity and sensitivity have been questioned. MATERIALS AND METHODS: To assess the diagnostic and prognostic values of tissue polypeptide specific antigen (TPS), carbohydrate antigen 19-9 (CA 19-9), vascular endothelial growth factor (VEGF-A), and carcinoembryonic antigen (CEA) we took serum samples in 56 patients with mass lesions in the pancreatic head. Among these patients, further investigations revealed pancreatic cancer in 20 patients, other malignant diseases in 12 and benign conditions in 24. RESULTS: Median CEA in all patients was 3.4 microg/L (range 0.5-585.0), median CA 19-9 was105 kU/L (range 0.6-1 300 00), median TPS 123.5 U/L (range 15.0-3350) and median VEGF-A 132.5 ng/L (range 60.0-4317). Area under the curve was 0.747, standard error (standard error [SE] =0.075) for CEA, 0.716 (SE=0.078) for CA 19-9 and 0.822 (SE=0.086) for TPS in ROC plots based on the ability of the tumours to distinguish between benign and malignant conditions. None of the markers significantly predicted survival in the subgroup of patients with pancreatic cancer. DISCUSSION: Our study shows that the markers may be used as fairly reliable diagnostic tools, but cannot be used to predict survival.

Prevalence of generalized anxiety disorder in general practice in Denmark, Finland, Norway, and Sweden.

OBJECTIVES: This study assessed the prevalence rate of generalized anxiety disorder among patients of general practitioners in Denmark, Finland, Norway, and Sweden and determined whether general practitioners recognize the condition and its correlates. METHODS: Data were gathered in September 2001. Participating patients received a questionnaire that included the Generalized Anxiety Questionnaire and the Depression Screening Questionnaire. The scale used DSM-IV criteria to identify generalized anxiety disorder and major depressive episode. General practitioners filled in a questionnaire about their patients' mental and physical illnesses, including generalized anxiety and major depressive episode. General practitioners' basic sociodemographic data and professional career information were also gathered. RESULTS: A total of 648 general practitioners and 8,879 patients participated in the study. The age-standardized rates for generalized anxiety disorder ranged from 4.1 to 6.0 percent for males and from 3.7 to 7.1 percent for females; for major depressive episode the rates ranged from 7.2 to 11.5 percent for males and from 9.9 to 14.2 percent for females. The proportion of generalized anxiety disorder cases recognized by general practitioners varied from 33 percent in Denmark to 53 percent in Norway. Recognition of generalized anxiety disorder by general practitioners was associated with presentation of anxiety problems by the patients. Physical symptoms as a reason for a consultation was associated with lowered recognition of generalized anxiety disorder. Previous diagnoses of generalized anxiety disorder or anxiety neurosis were associated with increased recognition of generalized anxiety disorder. CONCLUSIONS: Of the total percentage of cases of generalized anxiety disorder in general practice (4.8 percent for males and 6.0 percent for females), only one-third to one-half of the cases were identified by the general practitioners.

Low frequency of phlebographic deep vein thrombosis after laparoscopic cholecystectomy--a pilot study.

To investigate the rate of deep vein thrombosis (DVT) after laparoscopic surgery, 50 patients underwent bilateral phlebography 7-11 days after laparoscopic cholecystectomy (LC). All received thromboembolism prophylaxis, either low molecular weight heparin (LMWH) or dextran. Three patients were converted to open cholecystectomy. D-dimer was investigated preoperatively, on day 1 and on the day of phlebography. One asymptomatic DVT was found. One phlebogram was incomplete. Seven phlebograms were not optimal but of sufficient quality to rule out DVT. The frequency of DVT was thus 1 of 49 or 2.0% (95% confidence interval, 0-6.0%). No anticoagulants were prescribed after discharge. No patient developed late thromboembolic complications. D-dimer values increased significantly at day 1 and were further increased at the time of phlebography. The frequency of phlebographical DVTs thus seems to be low despite prophylaxis of questionable efficacy. The D-dimer values, however, suggest that the effects of LC on coagulation/fibrinolysis have a duration of longer than 1 week.