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Y Huet

Publications and source records attributed to Y Huet.

At least 19 recordsLinked to original sources

Risk of deep-venous thrombosis after hospital discharge in patients having undergone total hip replacement: double-blind randomised comparison of enoxaparin versus placebo.

BACKGROUND: The risk of deep-vein thrombosis (DVT) and pulmonary embolism after total hip replacement (THR) surgery may persist after hospital discharge, but the extent of the risk is not known. We carried out a single-centre, prospective, randomised, double-blind trial with the aims of quantifying this risk and assessing the efficacy of continued prophylactic treatment. METHODS: At hospital discharge 13-15 days after surgery, we recruited 179 consecutive THR patients who had no DVT visible on bilateral ascending venography of the legs. The patients were randomly assigned subcutaneous enoxaparin (40 mg, once daily; n = 90) or placebo (n = 89) for 21 (19-23) days. The primary endpoint was the occurrence of DVT or pulmonary embolism. Venography was repeated at the end of 21 days' treatment or earlier if necessary. FINDINGS: There were no deaths and no symptomatic pulmonary embolisms during the study or follow-up periods. Of 173 patients with evaluable venograms, intention-to-treat analysis of efficacy showed that the rate of DVT at day 21 after discharge was significantly lower in the enoxaparin group than in the placebo group (6 [7.1%] vs 17 [19.3%], p = 0.018). Distal DVT was detected in one (1.2%) patient in the enoxaparin group and in ten (11.4%) patients in the placebo group (p = 0.006). Proximal DVT was observed in five (5.9%) patients in the enoxaparin group and in seven (7.9%) patients in the placebo group (p = 0.592). A perprotocol analysis of efficacy in 155 patients confirmed these findings. Safety was good; three minor bleeding episodes occurred in the enoxaparin group and one in the placebo group, but none of these episodes necessitated withdrawal from the study. INTERPRETATION: In patients who have undergone THR surgery, are without venogram-proven DVT at hospital discharge, and do not receive antithrombotic prophylaxis after discharge, the risk of late-occurring DVT remains high at least until day 35 after surgery. Continued prophylaxis with enoxaparin is effective and safe in reducing this risk.

Aged

Efficacy and safety of postdischarge administration of enoxaparin in the prevention of deep venous thrombosis after total hip replacement. A prospective randomised double-blind placebo-controlled trial.

Although venous thromboembolism has occasionally been reported after hospital discharge in patients who have undergone total hip replacement (THR), this risk has not been fully quantified and the usefulness of a prophylactic treatment has not been evaluated. We conducted a single-centre prospective randomised double-blind clinical trial in 2 parallel groups of patients who had undergone THR and were free of deep venous thrombosis (DVT) at discharge, as assessed by bilateral ascending venography. During hospitalisation, all patients received a low molecular weight heparin, enoxaparin (enoxaparin sodium), as a prophylactic treatment for venous thromboembolism. Just before hospital discharge (15 +/- 1 days from surgery) 179 consecutive patients were randomly assigned to receive subcutaneous enoxaparin 40mg (n = 90) or placebo (n = 89) once daily for 21 +/- 2 days. The primary efficacy outcome was defined as the occurrence of DVT and/or documented pulmonary embolism (PE). DVT was assessed by ascending bilateral venography performed 21 +/- 2 days after randomisation or earlier if necessary. Secondary efficacy outcomes were the occurrence of proximal and distal DVT. Safety outcomes were defined as the occurrence of major and minor haemorrhage, other adverse events and changes in laboratory parameters. All patients underwent a 3-month follow-up. There were no deaths or cases of clinical PE during the study and the follow-up periods. In 173 patients with evaluable venograms, analysis of efficacy on an intention-to-treat basis showed that the incidence of DVT at day 21 was significantly lower in the enoxaparin group (6 of 85; 7.1%) than in the placebo group (17 of 88; 19.3%; p = 0.018), a risk reduction of 63%. Distal DVT was less frequent in the enoxaparin group than in the placebo group (1.2 vs 11.4%; p = 0.006) but there was no significant difference between groups in the incidence of proximal DVT. A 'per-protocol' analysis of efficacy in 155 patients confirmed the results for total and distal DVT, but also showed a trend in efficacy in favour of enoxaparin with regard to the incidence of proximal DVT (p = 0.064). Enoxaparin was safe in comparison with placebo: only 2 minor bleedings occurred in the enoxaparin group and there was no difference in the incidence of other adverse events between the 2 groups. In patients undergoing THR, the risk of late-occurring DVT remained high during the 21 days after hospital discharge in the placebo group. Prophylactic treatment with enoxaparin reduced the risk and was well tolerated in this context.

Aged

Evaluation of risk factors for laryngeal edema after tracheal extubation in adults and its prevention by dexamethasone. A placebo-controlled, double-blind, multicenter study.

Because laryngeal edema (LE) after tracheal extubation is likely to result from an exudative response, corticosteroids often are given routinely as a preventive treatment. No adequate controlled study supports this strategy, however. A prospective, randomized, placebo-controlled, double-blind, multicenter trial that included 700 consecutive patients requiring tracheal intubation and mechanical ventilation was conducted to determine risk factors for LE occurrence after tracheal extubation in adults and to evaluate the efficacy of corticosteroids in its prevention. One hour before extubation, patients were given either an intravenous bolus of 8 mg dexamethasone or a placebo. Patients were divided into two groups: 1) those in whom short-duration intubation (SDI, less than 36 h) was administered; and 2) those in whom long-duration intubation (LDI, more than 36 h) was administered. Minor LE was diagnosed when either stridor or laryngeal dyspnea, or both, occurred; major LE was diagnosed when reintubation due to LE was required, with LE evidenced during direct laryngoscopy. The overall incidence of LE was 4.2% and varied among the six participating centers from 2.3 to 6.9% (not significant). In only seven patients (1%), all with LDI, was tracheal reintubation required for LE. Laryngeal edema occurred more frequently after LDI than after SDI (7.2 vs. 0.9%; P less than 0.001). It also was more frequent in female than in male patients (20/284 vs. 8/379; P less than 0.05), irrespective of intubation duration and treatment. There was no association between LE and either difficulty/route of intubation or admission diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Failure of the intracaval filter of Günther to prevent recurrence of pulmonary embolism--report of two cases.

Two out of nine patients in which inferior vena cava interruption was performed with a Günther filter developed a recurrent pulmonary embolism. In both cases, the filter had moved down and the anchoring legs had perforated the wall of the vena cava. The source of the pulmonary embolism was a clotted basket filter. Anticoagulation was given for two weeks in one patient and six months in the other after insertion of the filter, but it had been stopped before the thrombotic event leading to the recurrent pulmonary embolism. The formation of the thrombi had probably been caused by the migration of the filter and the subsequent perforation, which may have been facilitated by the cessation of the anticoagulation.

Adult

Treatment of established venous thromboembolism with enoxaparin: preliminary report.

Unfractionated heparin is effective in the treatment of deep venous thrombosis and pulmonary embolism but may lead to significant side-effects (bleeding complications and thrombocytopenia). Low molecular weight heparin fragments have been shown to be as effective as unfractionated heparins during prophylaxis with a once-daily injection regimen. The aim of this open study was to assess the tolerance and the efficacy of enoxaparin in established venous thromboembolism. The study included 36 consecutive patients (mean age 60 years) (range 13-87) with recent deep vein thrombosis (less than 5 days) documented by venography. All patients received enoxaparin twice daily at a fixed dosage of 2 mg/kg/day. The efficacy was assessed by the evolution of Arnesen venographic score. Seventeen patients showed a moderate improvement (less than 35%) and 17 patients had a marked improvement (over 35%). Two patients were not evaluated for efficacy because they displayed bleeding complications. No relationship was found between anti-Factor Xa level and regression of venographic score. In conclusion, subcutaneous administration of enoxaparin proved to be an effective antithrombotic therapy. A fixed dosage of 2 mg/kg/24 h should be the basis of the randomized controlled study ongoing at the present time.

Drug Tolerance

[A survey on thromboprophylactic methods in brain surgery].

A 124 items survey on thromboprophylactic methods in neurosurgery has been conducted in the main neurosurgery centers of France, Italy, Belgium, Switzerland and Luxemburg. Its results put forward the diagnostic and prevention procedures as well as their indications and contra-indications. They also give information on the practice and problems of the different teams. The working out of new heparins (low molecular weight) gives real hopes that should be supported by extensive tests in neurosurgery.

Brain

Protective cardiovascular effects of diazepam in experimental acute chloroquine poisoning.

To assess the effects of diazepam in chloroquine poisoning, we studied pentobarbital anesthetized and mechanically ventilated pigs. All the pigs received 50 mg.kg-1 chloroquine given intravenously for 25 min. Eight pigs acted as control (group C). Another 7 were treated with diazepam given intravenously 5 min after the end of chloroquine infusion: 2 mg.kg-1 of diazepam for 2 min, then 1 mg.kg.h-1 for 25 min (group D). Thereafter, all pigs were sacrificed. In both groups the chloroquine infusion induced a large fall in arterial pressure, a decrease in heart rate, and an increase in QRS duration. No difference was observed between the 2 groups for weight, systolic and diastolic arterial pressures, heart rate, QRS and QT durations before diazepam. After diazepam, systolic and diastolic arterial pressures, heart rate, urine volume, urinary excretion of chloroquine, plasma and blood cell chloroquine levels were higher, whereas QRS duration was lower, in group D compared to group C. No difference was observed between the 2 groups for urinary concentration of chloroquine, the ratio between plasma and blood cell chloroquine levels, hepatic, cardiac, and skeletal muscle chloroquine levels, and QT duration. After diazepam, the slope of the regression curve between QRS duration and plasma chloroquine levels was reversed in group D compared to group C. We conclude that diazepam counteracts some haemodynamic and electrocardiographic changes, and increases urinary excretion of chloroquine, in acute experimental chloroquine poisoning.

Animals

[Value of a fraction of low molecular weight heparin, enoxaparine, in patients at high risk of hemorrhage and thrombosis].

Treatment of patients with both thromboembolic manifestations and acute bleeding episodes is poorly defined. The use of low molecular weight heparin fractions has been shown to provide prophylactic antithrombotic activity in humans, with the possibility of fewer hemorrhagic complications because of their low anticoagulant activity and weaker action on platelets. An open trial was carried out in 50 patients. 47 of whom had a recent history of thromboembolic accident (34 venous thrombosis, including 13 with pulmonary embolism, 9 systemic arterial episodes, 4 cardiac emboli) and 3 who required prophylaxis. Conventional heparin therapy was contraindicated in all patients: 30 because of major digestive or muscle hemorrhage and 20 with high hemorrhagic risk (neurosurgery, deep thrombocytopenia). Enoxaparine (Laboratoire Pharmuka, Gennevilliers) was administered as 1 mg/kg/24 hours as 2 divided injections with adjustment to maintain an anti-Xa activity of 0.1 to 0.4 IU/ml. Antithrombotic efficacy as function of type of pathology was rated excellent in all patients, while tolerance, evaluated similarly by tests chosen as a function of type of hemorrhage, was good: one patient had moderate bleeding after accidental overdose and 4 patients minor bleeding. Enoxaparine by subcutaneous injection could represent a new therapeutic approach by improving the efficacy/risk ratio in this type of patients.

Blood Coagulation Tests

Treatment of acute pulmonary embolism by a low molecular weight heparin fraction. A preliminary study.

We evaluated the antithrombotic efficacy of the low molecular weight heparin (LMWH) fraction PK 10169 in nine consecutive patients with acute pulmonary embolism documented by pulmonary angioscan and angiography. Therapy with PK 10169 was initiated by an i.v. bolus of 0.5 mg/kg, followed by a continuous intravenous infusion during the first 10 days; the drug was then given subcutaneously twice daily during the following 15 days. The dosage of PK 10169 was adjusted by daily measurements of anti-Xa and anti-IIa activities using amidolytic methods. For a dosage ranging from 1.4 to 4.1 mg/kg per day during the i.v. period and from 0.7 to 3.5 mg/kg per day during the s.c. period, the anti-Xa activity ranged from 4 to 8.7 PK U/ml and from 4.5 to 7.2 PK U/ml respectively. Clinical improvement was observed in all the patients and was consistent with progressive reperfusion evaluated by successive angioscans. No recurrence of pulmonary embolism occurred. No deleterious hemorrhagic side-effects were observed, even in two patients at high risk of bleeding. In this pilot study, the LMWH fraction PK 10169 proved to be an effective anticoagulant therapy during the first three weeks after pulmonary embolism in man.

Acute Disease

Hemodynamic, gas exchange, and hormonal consequences of LBPP during PEEP ventilation.

Hemodynamic, gas exchange, and hormonal response induced by application of a 25- to 40-mmHg lower body positive pressure (LBPP), during positive end-expiratory pressure (PEEP; 14 +/- 2.5 cmH2O) were studied in nine patients with acute respiratory failure. Compared with PEEP alone, LBPP increased cardiac index (CI) from 3.57 to 4.76 l X min-1 X m-2 (P less than 0.001) in relation to changes in right atrial pressure (RAP) (11 to 16 mmHg; P less than 0.01). Cardiopulmonary blood volume (CPBV) measured in five patients increased during LBPP from 546 +/- 126 to 664 +/- 150 ml (P less than 0.01), with a positive linear relationship between changes in RAP and CPBV (r = 0.88; P less than 0.001). Venous admixture (Qva/QT) decreased with PEEP from 24 to 16% (P less than 0.001) but did not change with LBPP despite the large increase in CI, leading to a marked O2 availability increase (P less than 0.001). Although PEEP induced a significant rise in plasma norepinephrine level (NE) (from 838 +/- 97 to 1008 +/- 139 pg/ml; P less than 0.05), NE was significantly decreased by LBPP to control level (from 1,008 +/- 139 to 794 +/- 124 pg/ml; P less than 0.003). Plasma epinephrine levels were not influenced by PEEP or LBPP. Changes of plasma renin activity (PRA) paralleled those of NE. No change in plasma arginine vasopressin (AVP) was recorded. We concluded that LBPP increases venous return and CPBV and counteracts hemodynamic effects of PEEP ventilation, without significant change in Qva/QT. Mechanical ventilation with PEEP stimulates sympathetic activity and PRA apparently by a reflex neuronal mechanism, at least partially inhibited by the loading of cardiopulmonary low-pressure reflex and high-pressure baroreflex. Finally, AVP does not appear to be involved in the acute cardiovascular adaptation to PEEP.

Adult

Low molecular weight heparin fractions as an alternative therapy in heparin-induced thrombocytopenia.

Eight patients with a delayed-onset heparin-induced thrombocytopenia, with thrombotic complications requiring immediate anticoagulation in 7 of them, were given low molecular weight heparin (LMWH) fractions as alternative therapy. This treatment led to normalization of platelet count within 3-5 days in 6 patients with clinical recovery in 5. In 2 patients, thrombocytopenia persisted despite LMWH therapy. In vitro platelet aggregation tests performed in all patients gave evidence of a relationship between the presence (or absence) of a LMWH-dependent platelet-aggregating factor in the patients' plasma and the persistence (or correction) of the thrombocytopenia with LMWH therapy. Although positive in vitro tests may not necessarily be associated with thrombocytopenia, in vitro testing may prove to be a useful guide before giving LMWH fractions as an alternative therapy in patients with heparin-induced thrombocytopenia requiring immediate anticoagulation.

Adult

Cardiopulmonary effects of ketanserin infusion in human pulmonary embolism.

The release of platelet-derived vasoactive substances, particularly serotonin (5-HT), have been implicated in the pulmonary vasoconstrictor response following acute pulmonary embolism. Therefore, we studied the effects of infusing ketanserin, a 5-HT blocking agent, upon pulmonary and systemic hemodynamics and gas exchange in 10 patients with severe acute pulmonary embolism. These patients evidenced 45 +/- 17% mean angiographic pulmonary vascular obstruction. Ketanserin significantly decreased the mean pulmonary arterial pressure from 26 +/- 6 to 23 +/- 5 mm Hg (p less than 0.001). The total pulmonary vascular resistance decreased from 9.1 +/- 3.2 to 8.3 +/- 2.5 mm Hg/L X min X m2 (p less than 0.001). However, the mean cardiac index was unchanged. The systemic arterial and right atrial pressures were significantly decreased after ketanserin. The PaO2 increased in all patients from 60.5 +/- 12.6 to 66.5 +/- 13.6 mm Hg (p less than 0.05), whereas the venous admixture was unchanged. This was attributed to an increased PVO2 (27 +/- 7 to 30 +/- 5 mmHg, p less than 0.01) secondary to a reduction of calculated peripheral oxygen consumption during ketanserin infusion. The results indicate ketanserin is a mild pulmonary vasodilator and can reduce the pulmonary hypertension and increase the PaO2 after pulmonary embolism.

Adult

Diagnosis of central venous catheter-related sepsis. Critical level of quantitative tip cultures.

The results of a simplified quantitative broth dilution quantitative tip culture (QTC) of 331 central venous catheters were compared with clinical data prospectively recorded in critically III patients to diagnose bacteremic or nonbacteremic catheter-related sepsis (CRS) (36 catheters), as opposed to contamination (42 catheters) or simple colonization from a distant septic focus (seven catheters). Thirty-five of 36 catheters associated with CRS yielded 10(3) colony-forming units per milliliter (CFU/mL) or more, and 3.8 X 10(2) Candida organisms grew from one. In contrast, 5 X 10(2) CFU/mL or less grew from 37 of 42 contaminated catheters. A QTC of 10(3) CFU/mL or more was 97.5% sensitive and 88% specific for the diagnosis of CRS. The QTC appeared especially useful for the diagnosis of CRS secondary to blood-borne seeding of catheters, or associated with coagulase-negative staphylococci.

Catheterization

Pulmonary complications occurring after allogeneic bone marrow transplantation. A study of 130 consecutive transplanted patients.

This report deals with 81 pulmonary episodes occurring in 130 consecutive patients who underwent allogeneic bone marrow transplantation for hematologic malignancy in the same unit over a 5-year period. These episodes observed in 69/130 patients (53%) were mostly of infectious origin, and were investigated by bronchoalveolar lavage (BAL). The main causes of pneumonia were: cytomegalovirus (CMV) (n = 25), bacterial pneumonia (n = 17), invasive aspergillosis (n = 11) and pulmonary hemorrhage (n = 9). The overall mortality due to or associated with pneumonia was 26/130 (20%). Graft-versus-host disease clearly increased the incidence of infectious pneumonia and the mortality due to or associated with pneumonia. Granulocyte transfusions did not influence the incidence of CMV pneumonitis. The main causes and risk factors for pneumonia are discussed. The role of BAL as a noninvasive procedure is stressed.

Adolescent

Comparative efficacy of pefloxacin and six other antimicrobial agents on Staphylococcus aureus experimental abscesses.

Pefloxacin (Pef) is a new quinolone which has been shown to have good in-vitro activity against Staphylococcus aureus, and to reach high tissue concentrations. Its efficacy was compared to that of 2 quinolone derivatives, norfloxacin (Nor) and ciprofloxacin (Cip) and to that of methicillin (Meth), cephalothin (Cep), pristinamycin (Pri) and vancomycin (Van), in an experimental model of S. aureus abscesses. Mice challenged with an intramuscular thigh injection of a calibrated inoculum developed local abscesses. Three S. aureus strains (with different antibiotic resistance profiles (Pase-, Pase+, MethR)) were used. In this model, the antibiotics showing the best ED50 following oral administration, against all three strains were Pef greater than Cip greater than Pri greater than Nor, by subcutaneous administration for the Pase- strain Pef = Cip greater than Cep greater than Van; for the Pase+ strain Pef = Cip greater than Van greater than Meth and for the Pase+ MethR strain: Pef = Cip greater than Van greater than Cep. These data indicate that pefloxacin and ciprofloxacin are highly active in vivo against various strains of S. aureus, and appear to be more potent than norfloxacin, vancomycin, cephalothin and methicillin.

Abscess