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G Janvier

Publications and source records attributed to G Janvier.

At least 55 records · Page 3Linked to original sources
PubMed1995

[Quality of psychomotor recovery after colonoscopy under general anesthesia using propofol. Value of tests of awakening].

Achieving colonoscopy under general anaesthesia entails the problem of ambulatory-care anaesthesia, in particular because perception of patient's recovery determines to some extent the length of monitoring following colonoscopy. The aims of the study was to assess the quality of patient's recovery after a colonoscopy under general anaesthesia while using propofol, by means of psychomotor-tests. METHODS--Colonoscopy was performed in 40 patients according to the following anaesthetic protocol: induction: propofol 2 mg/kg, continuous support: propofol 10 mg/kg/h i.v. with a 50 mg bolus in case of insufficient sedation; series of 3 psychomotor-tests were performed the day before and 1 hour, 3 hours and 6 hours after colonoscopy. The 3 psychomotor-tests studied: coordination (Newman test), time-space orientation and short-term memory. RESULTS--Forty patients, 25 females and 15 males, underwent colonoscopy with general anaesthesia for an average time-period of 22 +/- 11 min. The mean dose of propofol used was 286 +/- 102 mg. Awakening was complete in all patients, according to physical criteria such as consciousness and cardiovascular status, 20 min after receiving colonoscopy. The average psychomotor-tests results over time were (as percentages of original values) (*P < 10(-3); **P < 0.05): [table: see text] At 6 hours, 35 patients (87.5%) had recovered to their original performance and at 3 hours, 30 patients (75%) retained 90% their former state as measured with 3 psychomotor-tests. Neither by age or sex nor by propofol doses used or length or anaesthesia, the study population differed significantly. CONCLUSION--Three hours after colonoscopy under general anaesthesia using propofol, 30 patients (75%) had recovered at least 90% to their initial performances. Newman test was the most disturbed but there was no predictive factor for the quality of recovery. Psychomotor-tests may be useful before authorizing early discharge after colonoscopy under general anaesthesia but other recommendations about conditions of discharge after sedation must be also implemented.

Anesthesia Recovery Period↗
PubMed1994

In vitro accuracy of three blood O2 saturation optic catheter systems.

OBJECTIVE: The measure of the precision and accuracy of three optic SvO2 systems in vitro (SAT-2 Baxter, oximetrix 3 Abbott, HEMOPRO-2 Spectramed in a wide range of saturations (24-85%) and hematocrit (20-40%). DESIGN: In vitro comparison of the results given by a Co-Oximeter and the SvO2 systems. MEASUREMENTS AND RESULTS: 144 blood samples were tonometered with a variety of gas mixtures. Measurements of SvO2 were compared to those obtained by means of a Co-Oximeter, the difference (dSO2) between paired values were calculated. Precision was evaluated from confidence intervals (2SD) and accuracy was tested using dSO2 figures. As there was no difference in either precision or accuracy among catheters for a given system, data obtained from a given system were pooled. Mean precision was 14.2%, 8.6%, 9% for the Spectramed, Baxter and Abbott systems, respectively. CONCLUSION: The rather low reliability of the optic method should be borne in mind in patients with low SvO2 and/or low hematocrit.

Analysis of Variance↗
PubMed1994

An ex vivo original test using radiotracers for evaluating haemocompatibility of tubular biomaterials.

The haemocompatibility of a vascular prosthesis can be estimated as the result of its interaction with blood components. The authors describe an ex vivo canine shunt for evaluating isotopic haemocompatibility in blood-wall interactions. Methods employing radioisotopic tracers can be used to dynamically monitor the adsorption of labelled blood cells and proteins on different biomaterial surfaces. This ex vivo test should enable materials to be assessed for quality according to two thrombogenic criteria: (i) number of adhered platelets mm-2 s-1; (ii) quantity of adsorbed fibrinogen expressed as microgram mm-2 s-1, which would provide the basis for a scale of haemocompatibility.

Animals↗
PubMed1994

[Use of Diprivan in radiology].

For radiological examinations, propofol is administered, depending on the indications, at following doses: for anxiolysis: i.v. bolus of 10-20 mg, repeated as required; for sedation with maintenance of spontaneous ventilation: i.v. bolus of 0.5 mg.kg-1 or continuous infusion of 3 mg.kg.h-1. for general anaesthesia: i.v. bolus of 2 mg.kg-1 and maintenance with a continuous infusion of 6-10 mg.kg-1.h-1. These doses are modified according to the patient's reactions and painful episodes. In neuroradiology, indications for anaesthesia include vascular explorations, MRI, computerized axial tomography, as well as biopsies of organs and tumors, with the exception of explorations in patients with tight stenoses of the carotid artery. The use of propofol for cardiological explorations is questioned in adults and mainly in children with a congenital cardiopathy. For some authors this agent is contra-indicated, as during induction it decreases, sometimes excessively, the mean arterial pressure.

Anesthesia, Intravenous↗
PubMed1994

Multispecific and heterogeneous recognition of the gag protein by cytotoxic T lymphocytes (CTL) from HIV-infected patients: factors other than the MHC control the epitopic specificities.

The HIV gag polyprotein is a major target for recognition by CTL in infected humans. Using recombinant vaccinia viruses (rVV) expressing truncations of the p24gag, and the p18gag, p15gag and HIV-2 p56gag proteins, the characterization of epitope regions recognized by in vitro-stimulated peripheral blood mononuclear cells (PBMC) from 18 infected patients has been studied. The gag-specific response of most individuals is polyclonal and multispecific, and interindividual variations between target epitope regions were frequently observed, despite shared MHC alleles. As CTL may play an important role in the control of HIV replication in infected hosts, these results have important implications for designing vaccine strategies.

Adult↗
PubMed1994

A canine ex vivo shunt for isotopic hemocompatibility evaluation of a NHLBI DTB primary reference material and of a IUPAC reference material.

Factors determining the thrombogenic response to particular artificial surfaces were investigated ex vivo in a canine shunt model. Methods using radioisotopic tracers made it possible to dynamically monitor the deposition of labelled blood cells and proteins on a NHLBI.DTB primary reference material polydimethylsiloxane (PRM.PDMS) and on a IUPAC reference material polyvinyl chloride (IUPAC.PVC). On the one hand, leukocyte affinity tau s(leu) (number of deposited leukocytes mm-2s-1) was not significantly different between IUPAC.PVC (tau s(leu) = 1.2-2.5) and PRM.PDMS (tau s(leu) = 1.5-3.4) and the fibrinogen adsorption rate varied from 33 to 48.10(-5) micrograms mm-2s-1 for both these materials. On the other hand, platelet affinity tau s(plat) (number of deposited platelets mm-2s-1) was significantly different (p < 0.05) for IUPAC.PVC and PRM.PDMS (tau s(plat)PVC = 683 +/- 200 > tau s(plat)PDMS = 327 +/- 80). Scanning electron micrographs of adherent platelets, red cells and leukocytes after blood contact ex vivo were performed after each experiment. This preliminary work contributes not only to quantify the adsorption of different radiotracers, but also to evaluate the superficial distribution of the labelled biological species on the inner surface of the tested biomaterials.

Animals↗
PubMed1993

Plasma levels of piperacillin and vancomycin used as prophylaxis in liver transplant patients.

The pharmacokinetics of piperacillin and vancomycin used intravenously as antibioprophylaxis were measured in the plasma and bile during orthotopic liver transplantation. Piperacillin (4 g and then 2 g every 4 h) and vancomycin (1 g and then 0.5 g every 6 h) were infused in 10 patients. During vascular clamping without venovenous bypass, clearance of both antibiotics decreased in relation to renal insufficiency. During the surgical procedure, volume of distribution of both drugs increased because of fluid redistribution. The peaks of piperacillin after first, second and third administrations were respectively 314, 265 and 210 mg.l-1, while trough levels were 46.5, 55.2 and 54.5 mg.l-1. The peaks of vancomycin were 54.4, 49.6 and 40.9 mg.l-1, while first and second trough levels were 9.5 and 12 mg.l-1. These plasma concentrations were quite similar to levels reported in healthy subjects despite large blood loss and fluid replacement. However, piperacillin trough concentrations (< 64 mg/l) were too low in relation to its concentration-dependent antibacterial activity and vancomycin peak concentrations (> or = 40 mg/l) were slightly too high in relation to its toxicity.

Adolescent↗
PubMed1993

Pontine myelinolysis following liver transplantation: a report of two cases.

Two cases of central pontine myelinolysis (CPM) following orthotopic liver transplantation (OLT) are reported. Several months after the onset of this neurological syndrome, the two patients are still alive but with severe neurological sequelae. Some patients undergoing emergency OLT present a high risk of CPM because of pre-existing malnutrition, encephalopathy, and hepatic insufficiency. All of these are associated with an inevitable abrupt rise in sodium serum concentration due to intraoperative compensation of blood losses with high-sodium content blood products. Whenever the renal capacity to excrete sodium is impaired by the surgical procedure, continuous intraoperative venovenous hemofiltration is recommended.

Adult↗
PubMed1993

Mathematical analysis of the upper respiratory tract from an anthropometric study.

In order to design a new, performed tracheal tube adapted to the shape of the upper respiratory tract, we have undertaken an anthropometric study from lateral x-rays of the neck in 130 patients with the head in a fixed position. In order to assess different clinical situations, we studied three groups of patients: group 1 = sitting, no tracheal tube; group 2 = supine, no tracheal tube; group 3 = supine, trachea intubated. We defined a standard coordinate system and determined mathematical curves for segments of the upper respiratory tract by a polynomial regression method. With these data it was possible to study the effects of physiological variations on the shape of the curves. It was then possible to determine at which region changes occur and the factors influencing these changes. We found that the relative position of the larynx was constant, whereas the hypopharynx exhibited the greatest change with the position of the head. These observations should allow us to construct a new, performed tracheal tube with elastic compliance properties to fit the changes occurring in the region of the hypopharynx.

Adolescent↗
PubMed1993

Fibrinolytic and hemorheologic alterations during and after elective aortic graft surgery: implications for postoperative management.

The hemorheologic and fibrinolytic variables of 15 patients undergoing elective aortic graft surgery were investigated before, during, and after surgery. During the operation, a relative hemodilution was induced intentionally by an infusion of crystalloids and albumin. This led to a decrease in hematocrit (35.5 +/- 6.3-->31.8 +/- 5.6%, P < 0.01), fibrinogen, and platelets, as well as a decrease in fibrinolysis (Euglobulin Clot Lysis Time increases 246 +/- 52-->300 +/- 46 min and fast-acting plasminogen activator inhibitor 1 [PAI-1] activity increases 10.5 +/- 6.9-->15.1 +/- 9 IU/mL, P < 0.01). There was also specific rheologic impairment with a dissociation of erythro-aggregates (primary aggregation time 3.37 +/- 2.63-->7.18 +/- 7.2 s). Tissue-type plasminogen activator (t-PA) antigen was only increased just after surgery (8.3-->14.5 ng/mL, P < 0.01). During the first postoperative week, the acute-phase response subsided. This was accompanied by an increase in fibrinogen, von Willebrand factor antigen, and plasma viscosity (1.33 +/- 0.13-->1.49 +/- 0.13 mPa x s, P < 0.01). Hematocrit and the extrinsic fibrinolytic system (t-PA/PAI) returned to baseline values, whereas intrinsic fibrinolysis remained altered (the Euglobulin Clot Lysis Time, reflecting total activity of plasminogen activators, was still increased). Postoperative management may benefit from a recognition of these two distinct phases induced by surgery. The acute-phase reaction of the first postoperative week is an added vascular risk factor and requires a specific therapeutic approach.

Aortic Diseases↗
PubMed1993

[Efficacy and tolerance of imipenem/cilastatin in the adjuvant treatment of surgery for peritonitis in patients over the age of 70 years].

Eighty eight patients over the age of 70 years, suffering from peritonitis, were treated with imipenem/cilastatin single-agent therapy as a complement to surgery. The recommended dosage was 30 mg/kg/day and could be increased up to 50 mg/kg/day, without exceeding four grams per day, administered by four infusions per day. Seventy three patients (32 males, 41 females) with a mean, age of eighty years and suffering from peritonitis due to perforation, were evaluated. One half of patients presented one or several risk factors on inclusion into the study, one third received ventilatory assistance and 28.5% presented with shock. The perforation was situated in the stomach and duodenum (N = 24), biliary tract (N = 8), small intestine (N = 3), caecum (N = 10) and colon or sigmoid (N = 28). The infection was polymicrobial in 57.4% of cases. Blood cultures were positive in seven patients and cultures remained sterile in seven patients. A clinical success was obtained in sixty four patients (87%): fifty-six patients were cured and eight were improved. Six patients died as a result of infection (mortality: 8.2%) and three were not improved. No failure was due to development of an imipenem-resistant organism. These results confirm the efficacy of imipenem/cilastatin single-agent therapy as a complement to surgery for severe intra-abdominal infections in this high-risk elderly population.

Aged↗
PubMed1992

[Spontaneous splenic rupture disclosing a pheochromocytoma].

Clinical manifestation of a phaeochromocytoma may range from no symptoms to an acute abdominal emergency. These abdominal emergencies are related to haemorrhagic necrosis of the tumour, or massive bleeding in the retroperitoneal space. The authors report a case of splenic rupture revealing a phaeochromocytoma. The mechanism of splenic rupture is discussed as is the conservative treatment of phaeochromocytoma during splenic surgery. The authors observed no correlation between plasma catecholamine concentration and blood pressure.

Adrenal Gland Neoplasms↗