Search PubMed⌕ Search

Biomedical subjects

P Barbier

Publications and source records attributed to P Barbier.

At least 55 records · Page 3Linked to original sources
PubMed1994

Pericardial effusion after cardiac surgery: incidence, site, size, and haemodynamic consequences.

OBJECTIVE: To evaluate the incidence, characteristics, and haemodynamic consequences of pericardial effusion after cardiac surgery. DESIGN: Clinical, echocardiographic, and Doppler evaluations before and 8 days after cardiac surgery; with echocardiographic and Doppler follow up of patients with moderate or large pericardial effusion after operation. SETTING: Patients undergoing cardiac surgery at a tertiary centre. PATIENTS: 803 consecutive patients who had coronary artery bypass grafting (430), valve replacement (330), and other types of surgery (43). 23 were excluded because of early reoperation. MAIN OUTCOME MEASURES: Size and site of pericardial effusion evaluated by cross sectional echocardiography and signs of cardiac tamponade detected by ultrasound (right atrial and ventricular diastolic collapse, left ventricular diastolic collapse, distension of the inferior vena cava), and Doppler echocardiography (inspiratory decrease of aortic and mitral flow velocities). RESULTS: Pericardial effusion was detected in 498 (64%) of 780 patients and was more often associated with coronary artery bypass grafting than with valve replacement or other types of surgery; it was small in 68.4%, moderate in 29.8%, and large in 1.6%. Loculated effusions (57.8%) were more frequent than diffuse ones (42.2%). The size and site of effusion were related to the type of surgery. None of the small pericardial effusions increased in size; the amount of fluid decreased within a month in most patients with moderate effusion and in a few (7 patients) developed into a large effusion and cardiac tamponade. 15 individuals (1.9%) had cardiac tamponade; this event was significantly more common after valve replacement (12 patients) than after coronary artery bypass grafting (2 patients) or other types of surgery (1 patient after pulmonary embolectomy). In patients with cardiac tamponade aortic and mitral flow velocities invariably decreased during inspiration; the echocardiographic signs were less reliable. CONCLUSIONS: Pericardial effusion after cardiac surgery is common and its size and site are related to the type of surgery. Cardiac tamponade is rare and is more common in patients receiving oral anticoagulants. Echo-Doppler imaging is useful for the evaluation of pericardial fluid accumulations after cardiac surgery. It can identify effusions that herald cardiac tamponade.

Adolescent↗
PubMed1994

Mesoglycan and sulodexide act as stabilizers and protectors of fibroblast growth factors (FGFs).

Heparin and heparan sulfate proteoglycans (HSPGs) stabilize FGFs which belong to heparin-binding growth factors (HBGFs) on active conformation. They also strongly potentiate their mitogenic activity on many cell types, and protect them against thermal denaturation and enzymatic degradation. In the present work we have tested two heparin-like substances named mesoglycan and sulodexide obtained from bovine intestinal mucosal extracts. These products are used as heparin, in various of therapeutic fields such as atherosclerosis or antithrombotic therapy. The compositions of mesoglycan and sulodexide are partially known and include chondroitin, dermatan and heparan sulfate. We have shown that mesoglycan and sulodexide potentiated the mitogenic activity of FGF1 and FGF2. The magnitude of this effect was identical with that of heparin used as a control substance but at double concentration. Mesoglycan and sulodexide also exerted stabilizing and protective effects on FGFs for heat denaturation and enzymatic degradation. The suppression of the protective properties after heparinase treatment of mesoglycan and sulodexide indirectly demonstrated the presence of heparan sulfate which was shown to represent about 60% of the commercial products.

Animals↗
PubMed1994

[Multiplane transesophageal echocardiography for the monitoring of cardiac surgery].

Multiplane transesophageal echocardiography (TEE) allows visualization of the heart and great vessels through an infinite number of imaging planes and improves the diagnostic capabilities of mono and biplane TEE. This study was undertaken to test whether MTEE is a useful intraoperative monitoring method during cardiac surgery. Intraoperative multiplane TEE was performed in 200 patients (mean age 56 +/- 19 years) as a part of the routine clinical care. We systematically acquired cardiac images from the gastric fundus (short and long axes of the ventricles), lower esophagus (four-chamber, two-chamber, and long axis), upper esophagus (13 views concerning the aorta, pulmonary artery, left and right atrium, systemic and pulmonary veins, coronary arteries, right ventricular outflow tract), and searched for complete views of the thoracic descending aorta. All views analyzed in the preoperative (immediately before cardiopulmonary bypass), intraoperative and postoperative phases evaluating: the angle between current and 0 degree at which each view was obtained; the success rate of each view; the usefulness of the different views in providing essential additional clinical information compared to 0 degrees and 90 degrees of the traditional biplane TEE. Most views of the heart and great vessels were visualized in oblique planes, and other views were significantly improved thanks to slight angle corrections. Multiplane TEE was particularly useful in the preoperative and postoperative phases of aortic dissection (11 cases), mitral valve repair (13 cases), left ventricular aneurysmectomy (9 cases), right atrial thrombosis (1 case), positioning of left ventricular hemopump (2 cases), mitral-aortic endocarditis (3 cases), bleeding from proximal suture of an aortic heterograft (1 case).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

[Transesophageal coronary flowmetry and ventricular diastolic properties in surgically treated aortic insufficiency].

In patients with aortic valve regurgitation anginal pain without coronary artery disease is a consequence of both impairment of coronary flow (CF) reserve and reduction of diastolic CF (D) due to a diminished coronary perfusion pressure (CPP). Aim of this study was to evaluate with transesophageal multiplane echocardiography CF pattern in 15 patients with severe aortic regurgitation (AR) in the operative room before and after aortic valve replacement and to correlate it with hemodynamic parameters of left ventricular systolic (echocardiographic fractional shortening area) and diastolic (Doppler E/A ratio of mitral flow and X/Y ratio of pulmonary venous flow; pulmonary wedge pressure) function. Patients were compared to a control group (C) of 10 subjects. Coronary flow was divided into systolic (S), protodiastolic (PD) and end-diastolic (ED) components. In AR we observed a reduction in D/S ratio (2.6 +/- 1.3 versus 3.5 +/- 0.8, NS) and an increase in PD/ED ratio (2.24 +/- 2.8 versus 1.05 +/- 0.15, p < 0.001). A positive correlation was observed between PD/ED ratio and left ventricular diastolic impairment (E/A ratio: r = 0.71, p < 0.001; wedge pressure: r = 0.70, p < 0.001) and a negative correlation with CPP (r = -0.6, p < 0.02). Forty-five min after aortic valve replacement diastolic function improvement and CPP increase were associated with a normalization of CF pattern (D/S = 4.35 +/- 1.9/PD/ED = 1.06 +/- 0.16). In conclusion in AR diastolic dysfunction and abnormal CPP are strictly related to the reduction in diastolic CF; valve replacement normalizes the former two parameters and redistributes CF in late diastole.

Aortic Valve↗
PubMed1993

Percutaneous pericardiocentesis versus subxiphoid pericardiotomy in cardiac tamponade due to postoperative pericardial effusion.

In a retrospective study, 42 patients with acute cardiac tamponade due to pericardial effusion were evaluated following cardiac surgery, and the pericardial fluid was drained by one of two alternative methods: two-dimensional echocardiographic-guided pericardiocentesis (2D-echo) or subxiphoid surgical pericardiotomy. During the first period (from 1982 to 1986), one of the two methods was chosen by the treating physicians, whereas in the second period (from 1986 to 1991), 2D-echo-guided pericardiocentesis was the treatment of choice. Percutaneous pericardiocentesis was performed using local anesthesia in 29 patients. A Tuohy needle was inserted at the left xipho-costal junction and, when fluid was obtained, 6 mL of saline solution was injected during 2D-echo contrast monitoring, and a multiple-hole, 6F, 30-cm catheter was inserted by means of a guidewire and positioned into the posterior pericardium, as near as possible to the atrioventricular groove. Complete drainage of pericardial fluid by percutaneous pericardiocentesis was obtained in 26 patients (89%). This procedure also allowed the evacuation of posterior and loculated effusions. Complications included two right ventricular punctures, which were immediately recognized by 2D-echo contrast and produced no serious consequences. Sixteen patients who underwent surgical pericardiotomy had complete evacuation of pericardial fluid without major complications (two of them suffered atrial arrhythmias during the procedure). The average amount of fluid drained, as well as the localization of the effusions, were the same for both groups. 2D-echo-guided pericardiocentesis was found to be a useful, safe, and simple technique. It can be used as an alternative treatment to subxiphoid pericardiotomy for cardiac tamponade due to postoperative pericardial effusions.

Adult↗
PubMed1993

Sustained cardiac diastolic changes elicited by ultrafiltration in patients with moderate congestive heart failure: pathophysiological correlates.

OBJECTIVE: To investigate the pathophysiological (cardiac function and physical performance) significance of clinically silent interstitial lung water accumulation in patients with moderate heart failure; to use isolated ultrafiltration as a means of extravascular fluid reabsorption. DESIGN: Echocardiographic, Doppler, chest x-ray evaluations, and cardiopulmonary tests at baseline, soon after ultrafiltration (veno venous extracorporeal circuit), and four days, one month, and three months later. SETTING: University institute of cardiology. SUBJECTS: 24 patients with heart failure due to idiopathic dilated cardiomyopathy or ischaemic myocardial disease with sinus rhythm and ejection fraction less than 35%. Twelve were randomised to ultrafiltration and 12 were taken as controls. MAIN OUTCOME MEASURES: Left ventricular systolic function (from ultrasonography); Doppler evaluation of mitral, tricuspid, and aortic flow and echo-Doppler determination of cardiac output; radiological score of extravascular lung water; right and left ventricular filling pressures; oxygen consumption at peak exercise and exercise tolerance time in cardiopulmonary tests. RESULTS: Soon after ultrafiltration (1976 (760) ml of fluid removed) the following was observed: a reduction in radiological score of extravascular lung water (from 15(1) to 9(1)) and of right (from 7.1 (2.3) to 2.3 (1.7) mm Hg) and left (from 17.6 (8.8) to 9.5 (6.4) mm Hg) ventricular filling pressures; an increase in oxygen consumption at peak exercise (from 15.8 (3.3) to 17.6 (2) ml/min/kg) and of tolerance time (from 444 (138) to 508 (134) s); a slight decrease in atrial and ventricular dimensions; no changes in the systolic function of the left ventricle; a reduction of the early to late filling ratio in both ventricles (mitral valve from 2 (2) to 1.1 (1.1)); (tricuspid valve from 1.3 (1.3) to 0.69 (0.18)) and an increase in the deceleration time of mitral and tricuspid flow, reflecting a redistribution of filling to late diastole. Variations in the ventricular filling pattern, lung water content, and functional performance persisted for three months in all cases. None of these changes was detected in the control group. CONCLUSIONS: Reduction of interstitial lung water was probably the mechanism whereby ultrafiltration modified the pattern of filling of the two ventricles and improved functional performance.

Aged↗
PubMed1993

Parental opinions about biomedical research in children in Tours, France.

In order to evaluate parental awareness of the law governing clinical trials in France (Loi Huriet), a study was performed by questionnaire between February and April 1991 in a maternity unit during the days following delivery. The response rate was 59%. 59% of the parents (319/541) were informed of the existence of the law by the media (75%) or their general practitioners (12%). Twenty-one percent (116/541) of the parents would accept the participation of their children in a clinical trial and 74% would refuse. The principal reasons for acceptance were: for the benefit of other children, contribution to medical progress and confidence in physicians. The reasons for refusal were: risk of side effects and unproven efficacy. Parents who would accept had more often received higher education (44%) than parents who would refuse (30%), the latter being less influenced by the explanations of physicians and less willing to accept that a physician should decide for them. Physicians should consider transmitting information directly to parents and indirectly via the media.

Adult↗
PubMed1993

[The improvement of the Doppler echocardiographic method for the estimation of pulmonary systolic pressure].

The formulas currently utilized for noninvasive evaluation of right ventricular systolic pressure (RVSP) include right ventricular-right atrial pressure gradient (RV-RAG) and right atrial pressure (RAP). The former is expressed by trans-tricuspid systolic flow velocity, the latter is generally assumed. We recently observed that ultrasound estimation of RAP through inferior vena cava collapsibility index (CI) may help in the choice of the more appropriate formula for the evaluation of RVSP. However, these traditional methods (method A:RV-RAG + 10; method B:RV-RAG x 1.1 + 14) have limitations, particularly when RAP is low. The present study was undertaken to improve noninvasive estimation of RVSP through new formulas based on CI prediction of RAP. One hundred and four patients, in whom tricuspid regurgitation was adequately documented with CW-Doppler, were included in this study. They were classified into 3 groups: Group 1 with CI > 45%, Group 2 with CI < or = 35%, Group 3 with CI 35-45%. RVSP was evaluated by 3 different methods: A, B, and C. Method C was based on CI, assigning 6, 16, or 9 mmHg to RAP (respectively, the mean values in the 3 groups of our previous study). Results indicate that method C improves noninvasive estimation of RVSP in Group 1 and Group 2, with respect to other methods, with reduction of the SEE and of the mean difference of the t-test between hemodynamic and echographic values. In Group 3, Doppler estimation by method A and C, and catheter measurements are comparable, whereas method B significantly overestimates the actual value.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Solubilization and promoter analysis of RNA polymerase from rice stripe virus.

The RNA-dependent RNA polymerase associated with rice stripe virus was dissociated from viral RNA (vRNA) by CsCl centrifugation. The solubilized RNA-free RNA polymerase transcribed a model RNA template 50 nucleotides in length carrying the 5'- and 3'-terminal conserved sequences of all four genome RNA segments. A 3'-terminal half molecule of the model template was also active as a template. Hence, we propose that the 3'-terminal conserved sequence serves as a promoter for the rice stripe virus-associated RNA polymerase. The solubilized enzyme, however, was unable to transcribe vRNA. The failure of the solubilized enzyme to transcribe vRNA is discussed in relation to the apparent loss of RNA polymerase activity after treatment of virions with high concentrations of salt.

Base Sequence↗
PubMed1992

Oxaflozane overdose in a child.

A case of severe poisoning in a 2 year-old child who ingested 150 mg of oxaflozane, a non-tricyclic antidepressant, is reported. After loss of consciousness, opisthotonos and coma, recovery was obtained with conservative treatment. Atropine-like symptoms were noted. The maximal plasma concentration of oxaflozane was 63 ng/mL. The elimination half-life for N-dealkyloxaflozane was 4.8 h.

Antidepressive Agents↗
PubMed1992

Seizure with hyponatremia in a child prescribed desmopressin for nocturnal enuresis.

We report a case of hyponatremia associated with a grand mal seizure in a 28 month-old child after intra-nasal desmopressin administration for high fluid intake with nocturnal enuresis. In view of the temporary symptomatic action and the seriousness of certain side-effects of desmopressin we recommend that desmopressin be used with caution in childhood enuresis.

Administration, Intranasal↗
PubMed1991

Characteristics of medication errors in pediatrics.

A six-month prospective study was carried out by 16 poison control centers in France to assess the epidemiology of medication errors in pediatrics. In this study, 1108 medication errors were analyzed. Mean population age was 3.2 years (median 2 years, range 3 days-15 years), and 30 percent of the children were under 1 year of age. The most frequent error characteristics were family responsibility, 87 percent (a member of the patient's family most often committed the error in medication use); parental prescribing decision, 31.5 percent (medication administered to the child by the parents without medical consultation or the advice of a pharmacist); incorrect execution of the prescription by the parents, 30 percent (error in dispensing, route of administration, etc.); oral forms, 52 percent (errors occurred most frequently with oral as opposed to other forms); incorrect dosage, 31.5 percent; and drug error, 30 percent (the drug dispensed was not the one prescribed). Iatrogenic injury occurred in 186 patients (17 percent) and 161 were hospitalized (15 percent). The majority of these were for surveillance only. The clinical outcome caused by medication error was unfavorable in two cases. The types of drugs most frequently misused included morphinic cough suppressants (9.5 percent), salicylates (9.1 percent), and ear, nose, and throat drops (9 percent); 459 proprietary medicines were specified. Prevention of medication errors should involve certain main requirements: formulations and package instructions specific to pediatric patients to ensure appropriateness and accuracy, detailed information given to patients by physicians and pharmacists about their prescriptions, and more public information concerning the risks of remedies or medication administered to children by parents who do not seek medical advice.

Adolescent↗
PubMed1991

The use of flumazenil in a neonate.

Side effects of benzodiazepines used during pregnancy are described in a neonate. Recurrent apnea was reversed after administration of flumazenil, a specific antagonist of benzodiazepines.

Apnea↗
PubMed1991

Effects of prenatal exposure to diazepam on exploration behavior and learning retention in mice.

Diazepam (2 mg/kg, DZP) or placebo were administered by oral gavage throughout gestation in 40 mice. The automatic hole board test for mice (Boissier and Simon) was used to measure the locomotor activity and the number of holes explored by the offspring (mean age 30.6 days). During the first test, this number represents curiosity. Its progressive decrease when the test is repeated (4 times at 1-day intervals) is a consequence of learning retention. In the first test, neither curiosity nor activity were linked with the mother's treatment or sex. During the next tests, there was no difference in locomotor activity between DZP and placebo groups. However, the DZP exposed pups explored fewer holes than controls. Although there was a tendency towards greater activity in the female group, the number of holes explored in the placebo group was significantly higher in females than in males. Paradoxically, this difference in learning memory function which exists between control males and females was not observed in the DZP group, corresponding to an impaired learning retention.

Administration, Oral↗
PubMed1990

Variation in the nucleotide sequence of a prolamin gene family in wild rice.

Variation in the DNA sequence of the 10 kDa prolamin gene family within the wild rice species Oryza rufipogon was probed using the direct sequencing of PCR-amplified genes. A comparison of the nucleotide and deduced amino-acid sequences of eight Asian strains of O. rufipogon and one strain of the related African species O. longistaminata is presented.

Amino Acid Sequence↗
PubMed1990

Superficial adenocarcinoma of the oesophagus arising in Barrett's mucosa with dysplasia: a clinico-pathological study of 12 patients.

Superficial adenocarcinoma of the oesophagus is defined as carcinoma limited to the mucosa or submucosa regardless of lymph node status. Columnar epithelium lined lower oesophagus, now generally referred to as Barrett's oesophagus, is probably the main cause of adenocarcinoma in the lower oesophagus. Twelve cases of superficial adenocarcinoma arising in Barrett's oesophagus are presented. They were observed over a 6 year period and taken from a series of 50 cases of patients with Barrett's oesophagus and adenocarcinoma, a prevalence of 24%. Endoscopic diagnosis of malignancy was made in six patients. The initial biopsies showed an adenocarcinoma in six patients and some degrees of dysplasia in the other six patients. Prior to surgery, a histological diagnosis of adenocarcinoma was made in all twelve patients. In four patients the adenocarcinoma was confined to the mucosa, and in eight it extended to the submucosa. One patient had a metastatic lymph node. Ten patients are alive without evidence of tumour spread after a mean follow-up of 30 months.

Adenocarcinoma↗