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M Delcroix

Publications and source records attributed to M Delcroix.

At least 55 records · Page 3Linked to original sources
PubMed1992

Cyclooxygenase inhibition aggravates pulmonary hypertension and deteriorates gas exchange in canine pulmonary embolism.

We examined the effects of cyclooxygenase inhibitors on pulmonary hemodynamics and gas exchange after experimental acute pulmonary embolism in 12 intact anesthetized dogs. Pulmonary hemodynamics were evaluated by pulmonary arterial pressure (Ppa)/cardiac output (Q) plots before and 60 min after autologous blood clot embolization and again 30 min after cyclooxygenase inhibition, either by acetylsalicylic acid (ASA, n = 6) or by indomethacin (INDO, n = 6). Gas exchange was assessed using the multiple inert gas elimination technique, at a constant intermediate Q, under each of these experimental conditions. Embolization increased Ppa at all levels of Q studied (p less than 0.001), increased true shunt (p less than 0.05), and shifted perfusion (Q) and ventilation (VA) distributions to lower and higher VA/Q (p less than 0.05), respectively. ASA and INDO further shifted Ppa/Q plots toward higher pressures (p less than 0.05). Concomitantly, the physiologic dead space increased after INDO (p less than 0.001), and the proportion of lung units with a high VA/Q increased and the inert gas dead space decreased after both ASA (p less than 0.05) and INDO (p less than 0.05). We conclude that, in experimental pulmonary embolism, structurally different cyclooxygenase inhibitors aggravate pulmonary hypertension and deteriorate gas exchange by an altered distribution of VA/Q essentially to lung units with a higher than normal VA/Q. These findings may be explained by changes in the distributions of both VA and of Q as a consequence of cyclooxygenase inhibition-associated increases in both bronchial and vascular tone in embolized lung regions.

Animals↗
PubMed1992

Almitrine and doxapram in experimental lung injury.

Almitrine and doxapram, two structurally unrelated peripheral chemoreceptor agonists, have been shown to enhance hypoxic pulmonary vasoconstriction in anesthetized dogs. We hypothesized that these drugs would increase pulmonary vascular tone and improve gas exchange in canine lung injury caused by oleic acid (OA). Pulmonary hemodynamics and gas exchange were investigated in pentobarbital-anesthetized dogs before and after intravenously administered OA 0.09 ml/kg and again after placebo (n = 6), almitrine 2 micrograms/kg/min (n = 6), or doxapram 20 micrograms/kg/min (n = 6) in a randomized order. Cardiac output (Q) was manipulated using a femoral arteriovenous bypass and an inferior vena cava balloon catheter to construct mean pulmonary artery pressure (Ppa)-Q plots in order to discriminate active from passive changes in Ppa. Gas exchange was assessed by measuring arterial PO2 and intrapulmonary shunt, determined using a sulfur hexafluoride infusion. OA increased Ppa over the range of Q studied, and it deteriorated gas exchange by an increase in intrapulmonary shunt. After OA, placebo had no effect on Ppa, arterial PO2, or intrapulmonary shunt. Both almitrine and doxapram further increased Ppa at all levels of Q studied, but they did not affect indices of gas exchange after OA. We conclude that in this experimental model of acute lung injury, almitrine and doxapram induce pulmonary vasoconstriction without, however, diverting blood flow toward better oxygenated lung regions.

Almitrine↗
PubMed1991

PEEP inhibits hypoxic pulmonary vasoconstriction in dogs.

The effects of an increase in alveolar pressure on hypoxic pulmonary vasoconstriction (HPV) have been reported variably. We therefore studied the effects of positive end-expiratory pressure (PEEP) on pulmonary hemodynamics in 13 pentobarbital-anesthetized dogs ventilated alternately in hyperoxia [inspired O2 fraction (FIO2) 0.4] and in hypoxia (FIO2 0.1). In this intact animal model, HPV was defined as the gradient between hypoxic and hyperoxic transmural (tm) mean pulmonary arterial pressure [Ppa(tm)] at any level of cardiac index (Q). Ppa(tm)/Q plots were constructed with mean transmural left atrial pressure [Pla(tm)] kept constant at approximately 6 mmHg (n = 5 dogs), and Ppa(tm)/PEEP plots were constructed with Q kept constant approximately 2.8 l.min-1.m-2 and Pla(tm) kept constant approximately 8 mmHg (n = 8 dogs). Q was manipulated using a femoral arteriovenous bypass and a balloon catheter in the inferior vena cava. Pla(tm) was held constant by a balloon catheter placed by left thoracotomy in the left atrium. Increasing PEEP, from 0 to 12 Torr by 2-Torr increments, at constant Q and Pla(tm), increased Ppa(tm) from 14 +/- 1 (SE) to 19 +/- 1 mmHg in hyperoxia but did not affect Ppa(tm) (from 22 +/- 2 to 23 +/- 1 mmHg) in hypoxia. Both hypoxia and PEEP, at constant Pla(tm), increased Ppa(tm) over the whole range of Q studied, from 1 to 5 l/min, but more at the highest than at the lowest Q and without change in extrapolated pressure intercepts. Adding PEEP to hypoxia did not affect Ppa(tm) at all levels of Q.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

[Evaluation of fetal lung maturity with the measurement of enzymatic activities in amniotic fluid: comparison of three ratios].

Measurement, in amniotic fluid, of gamma-glutamyl-transferase (GGT) alkaline phosphatase and of thermostable and thermolabile (TLAP) isoenzyme allows to anticipate the unexpected risk of hyaline membrane disease. ROC method adapted to three ratio of these enzymatic activities shows that TLAP/GGT is the most performant at the level of 0.9 with a sensitivity of 96% and a specificity of 60%.

Alkaline Phosphatase↗
PubMed1991

[Value of amniotic gamma-glutamyl-transpeptidase assay in the diagnosis of fetal digestive stenosis after 24 weeks of amenorrhea].

In 18 women compared with 1,181 controls, foetal digestive tract stenoses were discriminated, independently of the gestational age, by a more than 50 IU/l level of gamma-glutamyl transpeptidase in the amniotic fluid. This test had a specificity of 99% and a sensitivity of 85% which was accounted for by the inclusion in the study of distal stenoses and oesophageal atresias, all conditions where the gamma-glutamyl transpeptidase level is normal. In cases with ultrasonically detected abdominal wall abnormalities, this test is also useful in the diagnosis of subjacent digestive tract stenosis.

Amniotic Fluid↗
PubMed1991

[Ultrasonic prenatal diagnosis of lip and palate cleft. Report of 10 cases].

Hare-lips and cleft palates are the most frequent manifestations of facial malformations (approximately 1 in 1,000 deliveries). The authors point out their technique for ultrasound assessment of the normal and pathological fetal face in the antenatal period. The antenatal examination gives an excellent diagnostic approach of the site and the nature and the extent of the abnormality. The screening for facial defects can be carried out routinely when studying the morphology in the second trimester of pregnancy or when there are other indications for doing this. Although the malformation is usually an isolated one, the management of these cases really depends mainly on any associated malformations than on the normality of the karyotype.

Cleft Lip↗
PubMed1991

[Amniotic infection and neonatal bacterial infection. Search for clinical and bacterial predictive arguments].

Amniotic fluid infection and its principal sequel bacterial infection of the newborn are major problems in obstetric pathology. The authors hav analysed prospectively 346 obstetrical casenotes over a period of 18 months in order to try to describe and specify the clinical features and to try and work out using bacteriological tests the risk of infecting the neonate by materno-fetal transmission. They compared a control group (27 case histories) and the group at risk (235 cases). 4% of the control group and 18.7% of the "at risk" group were biologically infected (p less than 10(-2)). The following are among the classical clinical criteria to correlate this risk: maternal pyrexia, premature delivery, urinary tract infections and fetal distress; an apparent lessening in active fetal movements is also well correlated to the risk of infection. The bacteriological criteria are: the presence of quantities of altered polymorphonuclear cells in the amniotic fluid--this seems to be more important than others (sensitivity = 70%, specificity = 89%, but positive predictive value = 60% and negative predictive value = 93%). From this study it should be possible to work out antenatally whether the newborn baby will be at high risk of developing an infection in order to consider giving antibiotics to prevent materno-fetal transmission.

Amnion↗
PubMed1990

Effects of vasodilators on gas exchange in acute canine embolic pulmonary hypertension.

Pulmonary vascular tone was investigated by the construction of pulmonary arterial pressure (PAP)/cardiac output (Q) plots, and gas exchange, by the multiple inert gas elimination technique, in 24 anesthetized dogs before and after pulmonary embolization of autologous clots. Three PAP/Q plots were obtained by a manipulation of venous return at baseline and 60 min and 110 min after embolization. Before the third PAP/Q plot, the dogs were randomly allocated to one of the following iv treatments: 1) placebo (n = 6); 2) prostaglandin E1 (PGE1) 0.4 microgram.kg-1.min-1 (n = 6); 3) hydralazine 2 mg/kg (n = 6); and 4) nitroprusside 10 microgram.kg-1.min-1 (n = 6). These vasodilators decreased systemic arterial pressure by a mean of 44%. Ventilation-perfusion (VA/Q) distributions were determined at the same Q (2.4 +/- 0.1 l.min-1.m-2, mean +/- SE) of each PAP/Q plot. Embolization increased the intercept and the slope of the PAP/Q plots (P less than 0.001). Distributions of VA/Q were only moderately impaired, with an increased dispersion of both VA and Q and a shift of VA distributions to higher VA/Q. PaO2 changed from 208 +/- 5 to 172 +/- 8 mmHg (P less than 0.01) (fraction of inspired O2 was 0.4). None of the treatments had any effect on VA/Q distributions. Placebo and PGE1 had no effect on PAP/Q plots. Hydralazine and nitroprusside reduced the slope of the PAP/Q plots. Thus, in this canine model of acute pulmonary embolism: 1) VA/Q distributions were moderately impaired accounting for only slight hypoxemia, and 2) pulmonary hypertension was partially reversible by hydralazine and by nitroprusside without associated non-flow-dependent change in VA/Q distributions and arterial oxygenation.

Acute Disease↗
PubMed1990

Effects of embolus size on hemodynamics and gas exchange in canine embolic pulmonary hypertension.

We examined the effects of different-sized glass-bead embolization on pulmonary hemodynamics and gas exchange in 12 intact anesthetized dogs. Pulmonary hemodynamics were evaluated by multipoint pulmonary arterial pressure (Ppa)/cardiac output (Q) plots before and 60 min after sufficient amounts of 100-microns (n = 6 dogs) or 1,000-microns (n = 6 dogs) glass beads to triple baseline Ppa were given and again 20 min after 5 mg/kg hydralazine in all the animals. Gas exchange was assessed using the multiple inert gas elimination technique in each of these experimental conditions. Embolization increased both the extrapolated pressure intercepts (by 6 mmHg) and the slopes (by 5 mmHg.l-1.min.m2) of the linear Ppa/Q plots, together with an 80% angiographic pulmonary vascular obstruction. These changes were not significantly different in the two subgroups of dogs. However, arterial PO2 was most decreased after the 100-microns beads, and arterial PCO2 was most increased after the 1,000-microns beads. Both bead sizes deteriorated the distribution of ventilation (VA)/perfusion (Q) ratios, with development of lung units with higher as well as with lower than normal VA/Q. Only 100-microns beads generated a shunt. Only 1,000-microns beads generated a high VA/Q mode and increased inert gas dead space. Hydralazine increased the shunt and decreased the slope of the Ppa/Q plots after 100-microns beads and had no effect after 1,000-microns beads. We conclude that in embolic pulmonary hypertension, Ppa/Q characteristics are unaffected by embolus size up to 1,000 microns.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Restored hypoxic pulmonary vasoconstriction by peripheral chemoreceptor agonists in dogs.

Hypoxic stimulation of the peripheral chemoreceptors inhibits hypoxic pulmonary vasoconstriction (HPV). On the other hand, almitrine, a peripheral chemoreceptor agonist, has been reported in some studies to enhance HPV. To further explore this apparent contradiction, we investigated the effects of two different low intravenous doses of almitrine on pulmonary arterial pressure (Ppa) versus cardiac index (Q) plots in 32 pentobarbital-anesthetized dogs ventilated alternatively in hyperoxia (FIO2, 0.4) and in hypoxia (FIO2 0.1). HPV, defined as a hypoxia-induced increase in Ppa over the entire range of Q studied, from 2 to 5 L/min/m2, was elicited in 16 dogs. In the first eight of these "responders," almitrine 2 micrograms/kg/min had no vascular effect, and in the other eight, almitrine 4 micrograms/kg/min inhibited HPV. In 16 other dogs, hypoxia did not affect Ppa over the entire range of Q. In these "nonresponders," almitrine 2 micrograms/kg/min (n = 8) as well as 4 micrograms/kg/min (n = 8) restored HPV. To answer the question whether the ability to restore HPV would be specific to almitrine, we administered intravenously the structurally unrelated chemoreceptor agonist doxapram at the dose of 20 micrograms/kg/min to an additional group of eight "nonresponders," and this treatment also restored HPV. Intravenous infusion of the malic acid solution solvent of almitrine had no effect on Ppa/Q plots in a final group of eight "nonresponders". We conclude that low dose almitrine and doxapram restore HPV in dogs with a naturally absent hypoxic pulmonary pressor response, probably by a direct effect at the pulmonary vessels.

Almitrine↗
PubMed1990

[Contribution of pelvic echography to the diagnosis of malformations of the utero-vaginal tract].

Pelvic ultrasound has become very important in the diagnostic planning of utero-vaginal malformations. Having studies 93 congenital malformations of the utero-vaginal tract, the authors used ultrasound investigations as a first or second line of approach. They are able to describe the way ultrasound can be used for each type of malformation. Ultrasound is undeniably reliable for diagnosing bilateral incomplete aplasia of the uterus; so avoiding the need for laparoscopy. When failure of the uterus to develop on one side occurs it is possible to look for a closed or canalized rudimentary uterine nodule to confirm the diagnosis of a pseudo-unicorn uterus. The diagnosis by ultrasound of a bifid uterus shows up by the appearance of a "V" shape on the bladder. An intra-uterine septum can be diagnosed according to how serious the embryological abnormality is on ultrasound. Similarly the difference between a bicornuate uterus that is really just arcuate or partially septate cannot always be made with ultrasound because the embryological defect is a relatively minor one. Ultrasound examination is able to give a lot of information in diagnosing and calculating how much of the menstrual fluid is held back either on one side or completely. Its value is less when the two sides of the uterus communicate with one another. Although this way of examining patients may make it possible quite often to avoid carrying out hysterosalpingogram and laparoscopy, its greatest value is found when all methods of diagnosis are combined and interpreted in the context of a clinical situation.

Congenital Abnormalities↗
PubMed1990

[HELLP syndrome. Apropos of a series of 9 cases without disseminated intravascular coagulation].

The Hellp syndrome defined as the association of micro-angiopathic haemolytic anemia, hepatic cytolysis and thrombocytopenia, correspond to a severe form of gravidic toxemia, combined to manifestations of classic-pre-eclampsia. This retrospective study, conducted over 6 years, concerns 9 cases of Hellp syndrome, including 2 occurring during the immediate post-partum. Only cases where this biological triad was obvious and not associated with manifestations of disseminated intravascular coagulation, were considered in this study. In addition to the usual criteria of gravidic toxemia, the early clinical manifestation occur, in this study, between 28 and 38 weeks of amenorrhea and gastrointestinal manifestations are predominant. The physiopathogenic hypotheses of this syndrome remain variable and management varies depending on the authors. Treatment is that of pre-eclampsia. Medical treatments (steroids, heparin, immunosuppressants,...) are discussed, but severe feto-maternal complications require, most of the time, a surgical approach, depending on the number of pregnancies, the obstetrical conditions, the stage of the pregnancy and the severity of the syndrome.

Adult↗
PubMed1989

[Computerized obstetrical record of the North Pas-de-Calais region].

The computerized obstetrical record of the North-Pas-de-Calais region proceeds from the desire of a number of people from the Regional Health Observatory, to dispose of a prospective epidemiologic tool in the field of perinatology. The objective is a better knowledge of the cause of perinatal death, analyzing the modalities of prenatal monitoring, delivery conditions, transfer of the newborns, as well as socio-economical conditions. The program manages the computerization of a usual obstetrical file, in the region, including approximately 200 items and allowing every possible comparison with the well-known CCIM record. The program permits local treatment of the data (statistical calculations) in each maternity hospital: rapid transmission of information between maternity and correspondents (computerized personalized mail), a base of agreement between the different protagonists: midwives, pediatricians, specialists, an easier collaboration with the protection agencies and, especially, the Regional Direction of Sanitary and Social Affairs, with automatic response to hundreds of questions of the yearly questionnaire, which saves a great deal of time and an extreme reliability of the information. This program is compatible with any IBM PC microcomputer and includes a hard disk of 10 or 20 mega-octets. The current price (microcomputer with hard disk, monitor, keyboard, letter-quality printer, management program) make all these performances available at a relatively low expense, under 25,000 francs (not including the tax).

Female↗
PubMed1989

[Use of a slow-release form of salbutamol in the treatment of threatened premature labor. A comparative study of 52 randomized cases compared with the immediate release form].

A randomised study was carried out to compare the effect of ordinary salbutamol with controlled release salbutamol as far as the sedative effect on the uterine muscle was concerned. Modifying the molecule for salbutamol gives it characteristics of a true "retard" form. This makes it possible to prescribe 2 tablets a day in 2 doses to copy the sedative effect on uterine muscle achieved when the treatment is given intravenously in cases of threatened onset of labour. The study was a double blind one with a placebo being used in two parallel groups after the populations had been compared for similar characteristics as far as the past history, the body build and the number of pregnancies was concerned. This made it possible to show that the two forms are strictly comparable and that there are no adverse side effects. This form of "retard" salbutamol seems to be particularly useful in repeated attacks of threatened premature labour and makes it likely that it will be taken more regularly with the avoidance of peaks in plasma and therefore improved tolerance. Furthermore, the action is longer and effective overnight.

Albuterol↗
PubMed1989

[Children of hyper- and hypothyroid mothers].

A multicenter study was able to utilize 120 medical files of children born from mothers who presented an abnormal thyroid function, 67 euthyroid goiters, 29 hyperthyroidisms, and 24 hypothyroidisms. In the first case, whether or not an inhibiting treatment was initiated, all children were perfectly normal. In case of maternal hyperthyroidism, the risk of malformations is not increased, deaths in utero and mostly in utero growth delays (1 case in 2) are more frequent. At birth, the child may present a hyperthyroidism due to the effect of SAT with elevated TSH and a goiter, sometimes compressing and impairing breathing, or also a hyperthyroidism due to transplacental crossing of stimulating immunoglobulins with possibility of thyreotoxic crises and heart failure. The diagnosis could be made in utero in the presence of tachycardia or with T4 and TSH assays in the cord. In case of maternal hypothyroidism, usually the children have no problems and the risk of neonatal hypothyroidism is mostly present in premature infants if the maternal balance is poor (2 in 24 cases in our series). Finally, in the reference population, the risk of neonatal hypothyroidism remains 1 in 3600 and justifies systematic screening on the 5th day of life.

Female↗
PubMed1988

[Heterotopic twin pregnancies. Review of the literature after a case where the 2 children survived].

A combination of an extra-uterine and an intra-uterine pregnancy is defined as heterotopic twin pregnancy. A case is reported where the 2 infants were born alive and have had a normal psychomotor development at 3 years of age. It is a case where the first observation taken by ultrasound made the diagnosis possible at 27 weeks of the pregnancy and therefore gave rise to the crucial problem of how to manage the case. Because of this case history we have discussed the frequency (one in every 30,000 pregnancies), the aetiological factors, the clinical factors, the prognostic factors and what is to be done. The discussion takes note of the modern ways of diagnosing it (ultrasound), of monitoring it and of handling in a specialised unit this exceptional kind of "high risk" pregnancy.

Adult↗
PubMed1987

Bacterial colonization of the large intestine in newborns delivered by cesarean section.

Colonization of the gastrointestinal tract in newborns delivered by Cesarean section occurs during the first days of life by bacteria provided by the environment. It is more rapid in breast-fed infants than in bottle-fed babies. The intestinal flora is more diversified if the infants receive formula feeding. The first bacteria encountered are facultative anaerobes; they remain predominant during the first two weeks of life. In comparison to vaginal delivery, there were low levels of strict anaerobes after Cesarean section; members of the Bacteroides fragilis group were still completely lacking after 14 days of life and Bifidobacteria were only isolated sporadically.

Bacteria, Anaerobic↗