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M Léone

Publications and source records attributed to M Léone.

8 recordsLinked to original sources

[The agents used for sedation in neurointensive care unit].

Sedation and analgesia can be routinely prescribed in head injury patients. The goals of such sedation are three: brain protection, prevention and treatment of intracranial hypertension and therapeutic facilitation. In such situation, the use of sedative and analgesic therapy should respect the rate of cerebral blood flow/cerebral oxygen consumption coupling while preserving cerebral perfusion pressure and decreasing the intracranial pressure. This treatment should have an analgesic and myorelaxing action with short and predictable time of action. The ideal sedation agent with all these properties does not exist. Only the combination of several different pharmacological classes of compounds may reach this goal. Benzodiazepines are the most frequently used agents. In most of the cases they are associated with analgesic agents such as opioid or ketamine. Opioids may be the basic analgesic agents because they do not produce brain haemodynamic modifications if arterial pressure is maintained. Among them, sufentanil, thanks to its pharmacokinetics properties, remains the most prescribed opioid. However, in the future, remifentanil that presents a fast elimination may be more frequently used for neurological follow up of patients. Ketamine whose use is subject of debate, has the main advantage of maintaining haemodynamic status. Ketamine has no side effects on brain haemodynamic when used with propofol or midazolam. Taking into account their deleting effect on haemodynamic status and immune system, barbituric are no longer used as long term sedative agents. However, their use is still recommended in the cases of refractory intracranial hypertension. Propofol remains the ideal sedative agent because of its short duration action but its use is limited by its cost. Its use may be recommended for short time sedations with or without an opioid drug. The curare use should be restrain to refractory intracranial hypertension to usual treatments and happening during stimulation.

Anesthetics↗

Role of glycopeptides in the treatment of septic complications after cardiac surgery.

Agents like Staphylococcus epidermidis and Staphylococcus aureus are common agents in both early and late prosthetic valve endocarditis (PVE). Streptococci, especially vividans and enterococci are more apt to occur late. Diphtheroids and gram-negative bacteria are also frequent in early and late PVE. Fungi are found at a frequency of 5 to 8% and a variety of unusual organisms are found in individual case reports. Treatment is based on parenteral therapy with a bactericidal agent that can achieve trough serum levels in excess of 8-10 X MICs of the infecting organisms. Initially the antibiotic selection should be active against the most common isolates. Because most S. epidermidis are beta-lactam-resistant, vancomcyin must be part of the initial empiric regimen. Vancomycin should be combined with rifampin or an aminoglycoside (usually gentamicin) or both. When there is a high level of resistance to aminoglycoside, vancomycin may be used alone until susceptibility data are available and then rifampin can be given together with an aminoglycoside or a quinolone to which the organism is susceptible. The aminoglycoside should be given for a maximum of 2 weeks, to avoid nephrotoxicity, and vancomycin for 6 weeks. Surgery is required in case of major emboli, hemodynamic decompensation, and uncontrolled infection. The presence of bacteremia for more than 1 week may warrant surgical intervention but, if the patient appears to be well and without emboli or hemodynamic problems, serum levels of antibiotic, particularly vancomycin, should be evaluated. Dosage regimen should be modified to achieve trough levels of vancomycin between 15 to 20 microg/ml. Use of vancomycin by continuous infusion may be considered with a targeted blood concentration of 15 to 20 microg/ml.

Anti-Bacterial Agents↗

[Catheter-related nosocomial urinary infections in intensive care: physiopathology, epidemiology and prevention].

OBJECTIVES: Nosocomial urinary tract infections associated with bladders catheters are common and poorly understood. Data on the prevention of urinary tract infections are numerous and heterogenous. This update article aimed at analysing mechanisms, epidemiology and prevention of these infections. DATA SOURCES: We searched in the Medline database for articles in English or French, without limiting date of publication, using the following key words separely or in combination: urinary tract infection, nosocomial, catheter, infection urinaire, sonde urinaire. STUDY SELECTION: We considered all categories of articles. DATA EXTRACTION: Data on prevention of nosocomial urinary tract infections were analysed in depth. DATA SYNTHESIS: The data on pathogenesis of nosocomial urinary tract infections are still controversial. Various means for preventing urinary tract infections have been recommended: addition of antibacterial agents to urinary drainage system, inclusion of antimicrobial components into the catheter itself, antibiotic prophylaxis or closed sterile drainage system. Their efficiency in intensive therapy unit has not yet been fully assessed. The therapy of these infections is still under debate and requires additional prospective studies to establish the optimal management. CONCLUSION: Catheter-associated urinary tract infections reflect the general hygiene policy, starting with nurse practice patterns at catheter insertion, and ending with antibio-therapy prescriptions by medical staff.

Anti-Bacterial Agents↗

[Glycopeptides].

OBJECTIVES: To review pharmacology, pharmacokinetic and therapeutic use of glycopeptides in intensive care units. DATA SOURCES: Extraction from Medline database of French and English articles on glycopeptides and search along with major review articles. DATA SELECTION: The collected articles were reviewed and selected according to their quality and originality. The more recent data were selected. DATA SYNTHESIS: Glycopeptides are bactericidal antibiotics which are only active against Gram positive species acting by inhibiting peptidoglycan synthesis. They had been in clinical use for almost 30 years without high-level resistance underlining. For ten years, there have been disturbing reports of first, resistance to vancomycin in enterococcal species and more recently in strains of Staphylococcus aureus by complex and large mechanisms of action. This new resistances may lead to a therapeutic impasse and a fatal issue for infected patients. The only response to this situation is the respect of prescription rules and the careful use of antibiotics. CONCLUSION: Considering their spectrum, glycopeptides are an antibiotic family which importance is fundamental to treat infected patients of intensive care units. Staff members of intensive care units are responsible for their good use.

Anti-Bacterial Agents↗

Cerebrospinal fluid penetration and pharmacokinetics of vancomycin administered by continuous infusion to mechanically ventilated patients in an intensive care unit.

Cerebrospinal fluid (CSF) penetration and the pharmacokinetics of vancomycin were studied after continuous infusion (50 to 60 mg/kg of body weight/day after a loading dose of 15 mg/kg) in 13 mechanically ventilated patients hospitalized in an intensive care unit. Seven patients were treated for a sensitive bacterial meningitis and the other six patients, who had a severe concomitant neurologic disease with intracranial hypertension, were treated for various infections. Vancomycin CSF penetration was significantly higher (P < 0.05) in the meningitis group (serum/CSF ratio, 48%) than in the other group (serum/CSF ratio, 18%). Vancomycin pharmacokinetic parameters did not differ from those obtained with conventional dosing. No adverse effect was observed, in particular with regard to renal function.

Adult↗