Transfusion-associated hazards: A revisit of their presentation.

As a therapy or a support to other therapies, despite being largely beneficial to patients in general, transfusion it is not devoid of some risks. In a moderate number of cases, patients may manifest adverse reactions, otherwise referred to as transfusion-associated hazards (TAHs). The latest French 2016 haemovigilance report indicates that 93% of TAHs are minor (grade 1), 5.5% are moderate (grade 2) and 1.6% are severe (grade 3), with only five deaths (grade 4) being attributed to transfusion with relative certainty (imputability of level [or grade] 1 to 3). Health-care providers need to be well aware of the benefits and potential risks (to best evaluate and discuss the benefit-risk ratio), how to prevent TAHs, the overall costs and the availability of alternative therapeutic options. In high-income countries, most blood establishments (BEs) and hospital blood banks (HBBs) have developed tools for reporting and analysing at least severe transfusion reactions. With nearly two decades of haemovigilance, transfusion reaction databases should be quite informative, though there are four main caveats that prevent it from being fully efficient: (ai) reporting is mainly declarative and is thus barely exhaustive even in countries where it is mandatory by law; (aii) it is often difficult to differentiate between the different complications related to transfusion, diseases, comorbidities and other types of therapies in patients suffering from debilitating conditions; (aiii) there is a lack of consistency in the definitions used to describe and report some transfusion reactions, their severity and their likelihood of being related to transfusion; and (aiv) it is difficult to assess the imputability of a particular BC given to a patient who has previously received many BCs over a relatively short period of time. When compiling all available information published so far, it appears that TAHs can be analysed using different approaches: (bi) their pathophysiological nature; (bii) their severity; (biii) the onset scheme; (biv) a quality assessment (preventable or non-preventable); (bv) their impact on ongoing therapy. Moreover, TAHs can be reported either in a non-integrative or in an integrative way; in the latter case, presentation may also differ when issued by a blood establishment or a treating ward. At some point, a recapitulative document would be useful to gain a better understanding of TAHs in order to decrease their occurrence and severity and allow decision makers to determine action plans: this is what this review attempts to make. This review attempts to merge the different aspects, with a focus on the hospital side, i.e., how the most frequent TAHs can be avoided or mitigated.

[A case of delayed fat embolism after a vertebral osteosynthesis]. / A propos d'un cas d'embolie graisseuse pulmonaire différée post-ostéosynthèse vertébrale.

A 37-year-old woman presented an acute respiratory distress syndrome six days after a post-traumatic vertebral osteosynthesis. First, a pulmonary embolism was suspected, and a thrombolysis realised. This diagnosis was secondary excluded, and the diagnosis of probable fatty embolism was established by the bronchoalveolar lavage. So, this case shows a delayed presentation of fatty embolism and permits a discussion about clinical presentation, and diagnosis methods of such pathology.

Impact of restricting fluoroquinolone prescription on bacterial resistance in an intensive care unit.

The purpose of this study was to assess the effect of reducing prescription of fluoroquinolones in an intensive care unit (ICU) upon bacterial resistance, particularly as regards Pseudomonas aeruginosa. For six months between January 2001 and June 2001, administration of fluoroquinolones was kept to a minimum. A bacteriological screening of patients was performed to assess the incidence of fluoroquinolone-resistant bacteria. There was a 75.8% restriction in prescriptions of fluoroquinolones. There was no significant change in bacterial ecology between the periods preceding (12 months) and following (12 months) restriction. There was a significant recovery of sensitivity of P. aeruginosa to ciprofloxacin (P

Acute thrombosis of a vena cava filter with a clot above the filter. Successful treatment with low-dose urokinase.

Inferior vena cava thrombosis is a major complication after filter placement. The thrombus can propagate through the filter leading to a high risk of pulmonary embolism. We report such a case in a patient with a Günther filter, successfully treated with urokinase, and we discuss the efficacy and the safety of thrombolytic therapy in such situations.

Death of terminally ill patients on a stretcher in the emergency department: a French speciality?

OBJECTIVES: To determine the frequency, modalities of admission and management of terminally ill patients who died on a stretcher in an emergency department (ED). DESIGN AND SETTING: Retrospective study in an ED of a university hospital. METHODS: Current place of residence, modalities of admission in ED, mortality probability scores and type of management were extracted for each patient in the terminal stage of chronic disease who died on a stretcher in our ED during a 3year period. RESULTS: Of 159 deaths observed in the ED, 56 (35%) concerned terminally ill patients. The illness was a malignancy in 22 cases, a neurological disease in 22 cases and a cardiopulmonary disease in 12 cases. Most of the patients were referred by their regular doctor. Seventy-two percent of the malignancy patients were living at home, 55% of the neurological patients came from nursing facilities and 58% of the cardio-respiratory patients came from the hospital. In 73%, 83% and 23% of the patients with malignancy, cardiopulmonary and neurological diseases, respectively, admission was related to the evolution of the chronic disease. Severity of illness on admission was similar whatever the disease. Request for compassionate end-of-life care was expressed in only 12.5%. At the ED, 91% of patients with neurological diseases received palliative support care. Supportive therapy was undertaken in one third of patients with malignancy or cardiopulmonary disease. CONCLUSION: An ED may be used as a place for dying for some terminally ill patients. This could be related to the legal opposition to withdrawal or withholding of life-support therapies as well as the absence of guidelines from scientific bodies.

Serum and ascitic procalcitonin levels in cirrhotic patients with spontaneous bacterial peritonitis: diagnostic value and relationship to pro-inflammatory cytokines.

OBJECTIVE: To assess the potential role of procalcitonin and pro-inflammatory cytokines, TNF-alpha, and IL-6, in the diagnosis of spontaneous bacterial peritonitis (SBP). DESIGN: Prospective study. SETTING: The emergency unit of a teaching hospital. PATIENTS: We included 21 patients with SBP and 40 patients with sterile ascitic fluid. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: For the diagnosis of SBP, the best markers were serum levels of procalcitonin with a cut-off value of 0.75 ng/ml, a sensitivity of 95%, a specificity of 98%, and ascitic fluid levels of IL-6 with a cut-off value of 5,000 ng/ml, a sensitivity of 100%, and a specificity of 88%. C-reactive protein and serum polymorphonuclear count have low sensitivity/specificity at 62/92% and 57/90%, respectively. From 21 patients with SBP, ascitic fluid to serum ratio of TNF-alpha and IL-6 was greater than to 2 in all cases with a mean at 6.2 +/- 6.5 and 34 +/- 31, respectively. By contrast, this ratio for procalcitonin was less than 1 in all cases with a mean at 0.31 +/- 0.25. We found no correlation between procalcitonin levels and cytokine levels in either ascitic fluid or serum. CONCLUSIONS: Serum procalcitonin level may become a useful marker for the diagnosis of SBP in cirrhotic patients. The low ratio of ascitic fluid to serum procalcitonin supports the hypothesis that procalcitonin is not produced intraperitoneally.

Endotoxaemia in patients with severe sepsis or septic shock.

OBJECTIVE: To examine the incidence and the bacteriological and clinical significance of endotoxaemia in ICU patients with severe sepsis or septic shock. DESIGN: Prospective review. SETTING: A 15-bed general ICU in a university hospital. PATIENTS: One hundred sixteen patients hospitalised in our ICU fulfilling Bone's criteria for severe sepsis or septic shock and with an available early endotoxin assay (chromogenic limulus assay). INTERVENTIONS: None. MEASUREMENTS AND RESULTS: The clinical characteristics of the population were: age 63.6 +/- 11.4 years; SAPS II: 45.4 +/- 15.6; mechanical ventilation: 72.4%; septic shock: 51.7% (n = 60); bacteraemia: 28.4% (n = 33); gram-negative bacteria (GNB) infection 47.4% (n = 55); ICU mortality: 39.6% (n = 46). Detectable endotoxin occurred in 61 patients (51.2%; mean level: 310 +/- 810 pg/ml). There was no relationship between detectable endotoxin and severity of infection at the moment of the assay. Endotoxaemia was associated with a higher incidence of bacteraemia (39.3% vs 16.3%; p = 0.01). There was a trend (p = 0.09) towards an association between positive endotoxin and gram-negative bacteraemia or GNB infection but this was non-significant. This relationship became significant only in the case of bacteraemia associated with GNB infection irrespective of the site of infection. CONCLUSION: Early detection of endotoxaemia appeared to be associated with GNB infection only in cases of bacteraemic GNB infection. Early endotoxaemia correlated neither to occurrence of organ dysfunction nor mortality in patients with severe sepsis or septic shock. This study suggests that the use of endotoxaemia as a diagnostic or a prognostic marker in daily practice remains difficult.

The oxygenation variations related to prone positioning during mechanical ventilation: a clinical comparison between ARDS and non-ARDS hypoxemic patients.

OBJECTIVES: To compare, in clinical practice, the oxygenation variations related to prone positioning (PP) during mechanical ventilation in ARDS and non-ARDS hypoxemic patients. DESIGN AND SETTING: Prospective observational study of data on consecutive patients treated with the same protocol in the intensive care unit (ICU) of a university hospital. PATIENTS: From May 1996 to December 1998, 226 PP periods without adjunction of nitric oxide (NO) inhalation and/or almitrine bismesylate infusion, performed in 59 mechanically ventilated hypoxemic patients (arterial oxygen tension/fractional inspired oxygen (PaO2/FIO2) ratio <300 mmHg) with no evidence of left ventricular failure, were included in this study. MEASUREMENTS: Arterial blood gas was measured before the PP, at 1 h from the beginning of the PP, at the end of the PP and 1 h after returning to the supine position. RESULTS: We analyzed 136 PP periods in 34 non-ARDS patients (60.2%) and 90 in 25 ARDS patients. The PP was repeated and the duration of the PP periods was: 10.6+/-0.22 h. The PP during the mechanical ventilation appeared to be safe and well tolerated. A PaO2/FIO2 ratio improvement at the end of the PP period, occurred for 196 periods (86.7%) with a mean PaO2/FIO2 ratio increase of +46.4+/-0.03% at the end of the PP periods compared to the baseline supine value. The PaO2/FIO2 ratio variations at 1 h after the start of the PP, at the end of the PP period and at 1 h after the return to supine were not different in ARDS or non-ARDS hypoxemic patients. The PaO2/FIO2 ratio improvement appeared to be more intense and more rapid in ARDS patients. CONCLUSIONS: In about 90% of periods, PP improved the PaO2/FIO2 ratio in patients with ARDS as well as in hypoxemic patients with non-ARDS. Studies are necessary to determine the impact of PP on survival and the mechanical ventilation duration in ARDS or non-ARDS hypoxemic patients.

Prospective study of nosocomial colonization and infection due to Pseudomonas aeruginosa in mechanically ventilated patients.

OBJECTIVE: To investigate the respective contribution of endogenous and exogenous transmission of Pseudomonas aeruginosa in the colonization of lungs in the mechanically ventilated patient, to estimate the role of P. aeruginosa colonization in the occurrence of severe infections, and to extrapolate appropriate control measures for the prevention of P. aeruginosa ventilator-associated pneumonia. DESIGN: Prospective study of the presence of P. aeruginosa (in stomach fluid, throat specimens, stool, and sputum) on admission, twice a week throughout the patient's stay, and in their environment. O-serotyping, pulsed-field gel electrophoresis, and arbitrarily-primed polymerase chain reaction were used to characterize the strains. SETTING: The two intensive care units (ICUs 1 and 2) of a university hospital. PATIENTS: During a 6-month period, 59 patients were included (21 in ICU 1 and 38 in ICU 2). RESULTS: P. aeruginosa was isolated in 26 patients, including ten pneumonia cases and seven colonizations on admission. The incidence of acquired colonization was statistically different between the two ICUs: 5.5 and 20.5 per 1000 days of mechanical ventilation, in ICUs 1 and 2, respectively. Endogenous acquisition was the main origin of P. aeruginosa colonization (21 of 26 patients) and the upper respiratory tract was the main bacterial reservoir in broncho-pulmonary colonization and infection. However, during the 6-month period of the study, a multidrug-resistant strain of P. aeruginosa O:11, isolated in the sink of the room of 12 patients, was found responsible for two colonizations (1 digestive, 1 throat/lungs) and one pneumonia. As a whole, from 26 cases of colonization/infection with P. aeruginosa, 5 were related to an exogenous contamination (environmental reservoir in 4 patients and cross-contamination in one patient). CONCLUSIONS: These results emphasize the need for applying various infection control measures to prevent colonization of patients with P. aeruginosa, including strategies to limit the potential of sinks from acting as a source or reservoir for this bacterium.

rG-CSF reduces endotoxemia and improves survival during E. coli pneumonia.

We investigated the effects of recombinant granulocyte colony-stimulating factor (rG-CSF) during canine bacterial pneumonia. Beagles with chronic tracheostomies received daily subcutaneous rG-CSF (5 micrograms/kg body wt) or placebo for 14 days, beginning 9 days before intrabronchial inoculation with E. coli. Animals received antibiotics and fluid support; a subset received humidified oxygen (fractional inspired O2 0.40). Compared with controls, rG-CSF increased circulating neutrophil counts (57.4 vs. 11.0 x 10(3)/mm3, day 1 after infection; P = 0.0001), decreased plasma endotoxin (7.5 vs. 1.1 EU/ml at 8 h; P < 0.01) and serum tumor necrosis factor-alpha (3,402 vs. 729 pg/ml at 2 h; P = 0.01) levels, and prolonged survival (relative risk of death = 0.45, 95% confidence interval 0.21-0.97; P = 0.038). Also, rG-CSF attenuated sepsis-associated myocardial dysfunction (P < 0.001). rG-CSF had no effect on pulmonary function or on blood and lung bacteria counts (all P = not significant). Other animals challenged with endotoxin (4 mg/kg i.v.) after similar treatment with rG-CSF had lower serum endotoxin levels (7.62 vs. 5.81 log EU/ml at 6 h; P < 0.01) and less cardiovascular dysfunction (P < 0.05 to < 0.002) but similar tumor necrosis factor-alpha levels (P = not significant) compared with controls. Thus prophylactic rG-CSF sufficient to increase circulating neutrophils during bacterial pneumonia may improve cardiovascular function and survival by mechanisms that in part enhance the clearance of bacterial toxins but do not improve lung function.

ICAM-1 and CD11b inhibition worsen outcome in rats with E. coli pneumonia.

We investigated whether inhibiting an endothelial adhesion molecule [intracellular adhesion molecule 1 (ICAM-1)] would alter outcome and lung injury in a similar fashion to inhibition of a leukocyte adhesion molecule (integrin CD11b) in a rat model of gram-negative pneumonia. Inhibition of ICAM-1 with monoclonal antibody (MAb) 1A29 (1 mg/kg sc or 0.2 or 2 mg/kg iv, q 12 h x 3) or of CD11b with MAb 1B6 (1 mg/kg sc, q 12 h x 3) were compared against similarly administered placebo proteins in rats challenged with intrabronchial Escherichia coli. After challenge, all animals were treated with antibiotics. ICAM-1 MAb (6 mg/kg, iv, total dose) increased mortality vs. control (P = 0.03). CD11b MAb (3 mg/kg, sc, total dose) did not significantly (P = 0.16) increase mortality rates, but this was not in a range of probability to exclude a harmful effect. All other doses of MAb had no significant effect on survival rates. ICAM-1 and CD11b MAbs had significantly different effects on the time course of lung injury, circulating white cells and lymphocytes, and lung lavage white cells and neutrophils (P = 0.04-0.003). CD11b MAb decreased, whereas ICAM-1 MAb increased these measures compared with control from 6 to 12 h after E. coli. However, from 144 to 168 h after E. coli both MAbs increased these measures compared with control rats but to a greater level with CD11b MAb. Thus both ICAM-1 and CD11b appear to be necessary for survival during E. coli pneumonia. Although these adhesion molecules may participate differently in early lung injury, with CD11b increasing and ICAM-1 decreasing inflammation and injury, both are important for the resolution of later injury. During gram-negative pneumonia the protective roles of ICAM-1 and CD11b may make their therapeutic inhibition difficult.

[Traumatic rupture of the aorta diagnosed by transesophageal echocardiography. Apropos of a case and review of the literature]. / Rupture traumatique de l'isthme aortique diagnostiquée par l'échographie transoesophagienne. A propos d'une observation et revue de la littérature.

The authors report the case of subadventitial rupture of the isthmus of the aorta due to trauma, diagnosed by transoesophageal echocardiography. The role of transoesophageal echocardiography compared with conventional diagnostic techniques is discussed. This method of investigation is a very good diagnostic tool in cases of closed trauma of the thorax.

[Bepridil and torsades de pointes: are the precautions of use respected?]. / Bepridil et torsades de pointes: les précautions d'emploi sont-elles respectées?

The torsades de pointes with bepridil are serious side-effects, known right from 1982, and for which definite therapeutic recommendations were decreed in 1984 then in 1991. The observations of 7 new cases drove us to discuss about the respect for these recommendations. From the study of these 7 middle-aged patients (+/- esm) 76.9 +/- 2.4, we have noticed that they all combined 3 risk-factors at least with an average (+/- esm) 3.71 +/- 0.29 (range 3-5). The non-respect for the methods of prescription of bepridil leads to serious trouble in the rate of heartbeat and can threaten vital prognosis. So, it is advisable for the practicians to be warmly and precisely informed and prescribe another anti-angina-pectoris treatment in high risk-patients.

[Anesthesia and general surgery in cardiac patients]. / Anesthésie et chirurgie générale chez le cardiaque.

Close cooperation is necessary between the cardiologist and anesthesiologist preoperatively in order to identify the risks associated with a surgical procedure. This article reviews the various types of anesthesia and their effects on the cardiovascular system, in particular in relation to the category of cardiovascular disease. Accurate definition of the operative risk involves thorough evaluation of three essential parameters: cardiovascular status, the type of surgery and the type of anesthesia. These high-risk patients require management not only pre- and peroperatively, but also postoperatively, which is the period when the majority of complications occur. Mention is also made of drug interactions between anesthetic and cardiovascular agents.

[Fatal voluntary poisoning with cibenzoline. Failure of conventional therapies]. / Intoxication volontaire mortelle à la cibenzoline. Echec des thérapeutiques conventionnelles.

BACKGROUND: Massive voluntary ingestion of cibenzoline causes major cardiotoxicity. We report on two cases where conventional treatments were ineffective. CASE REPORTS: Two patients were admitted to the intensive care unit of a University Hospital after massive voluntary intoxication with cibenzoline. Delay to admission after ingestion of cibenzoline was 1.5 and 4 hours. Circulatory impairment developed rapidly in both patients due to major atrioventricular and ventricular conduction disorders. Conventional intensive care procedures (sodium lactate and adrenaline) were performed but only provided temporary and incomplete efficacy. Outcome was fatal in both cases. DISCUSSION: The lethal potential of cibenzoline is very high. Extra-corporeal cardiocirculatory assistance might be an advisable measure if conventional therapy is unsuccessful. No clearly defined prognosis factors in cibenzoline intoxications have been reported.

[Justification of routine puncture of ascites in cirrhotic patients admitted to emergency hospital units]. / Justification de la ponction d'ascite systématique chez le patient cirrhotique admis aux urgences.

OBJECTIVES: Spontaneous bacterial peritonitis (SBP) is a frequent, serious, recurrent complication, occurring in 10 to 30% of cirrhotic patients hospitalized with ascites. The key to diagnosis of SBP is ascites paracentesis and polymorphonuclear count in ascitic fluid. The purpose of our study was to evaluate sensitivity and specificity of clinical and biological criteria in diagnosis of 5 BP. METHODS: We prospectively reviewed 30 adult cirrhotic patients admitted in our emergency department with ascites. Ascites paracentesis was performed in each patient, and SBP diagnosis was based on either positive bacteriological culture or polymorphonuclear count above 250/mm3 in ascitic fluid. Classical criteria for SBP were recorded: blood pressure under 90 mm of Hg, abdominal pain, temperature above 38.5 or under 36.5, jaundice, encephalopathy, increased serum bilirubin or creatinine, leukocyte blood count about 12 G/l. We evaluated sensitivity and specificity of those criteria in SBP, and compared their frequency in patients with SBP or sterile ascitic fluid. RESULTS: Thirty patients were included in our series, and in 14 of them a SBP was diagnosed. A significant difference was observed between spontaneous bacterial peritonitis and sterile ascitic fluid for abdominal pain and temperature abnormalities, but specificity and sensitivity of these criteria were very low. Moreover, SBP was asymptomatic in 7%. CONCLUSION: Due to the high rate of mortality in patients with SBP we recommend diagnostic procedures for this frequent complication as soon as patient is admitted in emergency department. This diagnosis must be based on ascitic fluid paracentesis, which has to be performed, in the emergency department, in every cirrhotic patient admitted with ascites. Indeed, SBP is often asymptomatic, and no clinical or bacteriological criteria can be considered as completely reliable for the diagnosis of spontaneous bacterial peritonitis.

[Bepridil: importance of serum level in treatment surveillance]. / Bépridil: intérêt du dosage sérique dans la surveillance du traitement.

OBJECTIVE: Despite precise recommendations for prescription and monitoring, tosades de pointes is still observed with bepridil. The purpose of this study was to demonstrate the contribution of bepridil serum assay in therapeutic supervision. PATIENTS AND METHODS: Seventy-five patients over 70 years of age were included. Prolongation of the QT interval was observed in 23 patients. RESULTS: The potential prognostic factors for increased QT interval as demonstrated by univariate logistic regression were hypokaliemia, bradycardia, renal failure and bepridil serum level. After multivariate logistic regression, the persisting causal factors for increased QT interval were hypokaliemia, bradycardia and bepridil serum level. CONCLUSION: Prolongation of the QT interval remains dependent on several variables. Bepridil determination during treatment is insufficient alone.

[Catheter infection in intensive care: influence of systematic replacement of central venous catheters on a guide wire every 4 days]. / Infections sur cathéters en réanimation: influence de l'échange systématique sur guide métallique tous les 4 jours de voies veineuses centrales.

OBJECTIVES: Determine whether systematic replacement of central venous catheters on a guide wire every 4 days leads to a lower rate of catheter infection. METHODS: We conducted a prospective randomized study comparing systematic catheter replacement with the standard procedure where one-way catheters are left in situ as needed. RESULTS: The study included 150 patients and 170 catheters. Catheter replacement on a guide wire was performed 169 times. The rate of infection was not significantly different between the group of patients with replacement (3.7 for 1000 catheter days) and the group with systematic replacement (5.4 for 1000 catheter days). No mechanical complications occurred during the replacement procedures on guide wires. CONCLUSION: We do not recommend systematically replacing catheters on a guide wire for the prevention of catheter infection. This procedure may however be indicated in case of suspected catheter infection as no mechanical of infectious complications occurred.

[Rapid diagnosis of the type of meningitis (bacterial or viral) by the assay of serum procalcitonin]. / Diagnostic rapide du type de méningite (bactérienne ou virale) par le dosage de la procalcitonine sérique.

OBJECTIVE: It has been shown that serum procalcitonin (PCT) can be used to differentiate bacterial from viral meningitis in children in all cases. The aim of this study was to demonstrate the interest of PCT in the management of suspected meningitis in adults. PATIENTS AND METHODS: We conducted a prospective study including 179 consecutive patients admitted to the emergency department for suspected meningitis. All samples were taken at patient admission. The discriminant potential between bacterial and viral meningitis was studied for cerebrospinal fluid parameters (cytology, protein, glucose, lactate) and serum parameters (C reactive protein, PCT). RESULTS: Thirty-two patients had bacterial meningitis, 90 had viral meningitis and meningitis was ruled out in 57. Among all studied parameters, the most discriminant for distinguishing between bacterial and viral meningitis in 100% of the cases proved to be serum procalcitonin with a threshold value of 0.93 ng/ml. CONCLUSION: Serum procalcitonin is an interesting parameter in the emergency department for management of meningitis suspicion in adults.

[Phlebitis following travel]. / Phlébite du transport. 16 observations.

The term of economy class syndrome has been used to describe the deep vein thrombosis which may follow air travel. The mechanisms suggested for this include tendency to clot formation in the legs secondary to the reduced venous return induced by the sitting position with direct compression of popliteal and femoral veins, and secondary to dehydration and haemo-concentration. However, these conditions are also observed with others means of transport. We describe 16 patients with deep vein thrombosis following travel by bus, car, truck and train. These 16 patients represent 3.4 percent of 465 patients with thromboembolism managed over a 52-month period in our department. All but one patients had one or more risk factors for deep vein thrombosis. The mean duration of the trip was 14.2 hours and the first symptom occurred less than a week after the journey in 75 percent of the patients. These first symptoms suggested deep vein thrombosis in 8, pulmonary embolism in 5, and deep vein thrombosis with pulmonary embolism in 3 patients. Regular non alcoholic drinks and regular walks seem to be sufficient to prevent deep vein thrombosis in the great majority of travellers. However, low dose heparin on a temporary basis or elastic stockings could be considered in high risk subjects.