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T Rakza

Publications and source records attributed to T Rakza.

11 recordsLinked to original sources
PubMed2001

[Anastomotic stenosis after surgical treatment of esophageal atresia: frequency, risk factors and effectiveness of esophageal dilatations].

UNLABELLED: Anastomotic stricture is the most common complication following the surgical repair of esophageal atresia, and is usually treated by esophageal dilation. OBJECTIVES: The aims of this study were to assess in an infant population operated on at birth for type III or IV esophageal atresia: 1) the frequency of esophageal stenosis following the repair of esophageal atresia, and associated factors; 2) the efficacy of esophageal dilation by the Savary-Gaillard bougie technique. MATERIALS AND METHODS: The medical records of 52 children presenting with esophageal atresia over a 5-year period were retrospectively reviewed. Gestional age and birth weight, duration of mediastinal and transanastomotic drainage, and anastomotic complications including leakage, stricture, and the presence of gastroesophageal reflux were recorded and analysed. Patients presenting with anastomotic stricture were compared with a group of children without stricture. The number of esophageal dilations, their efficacy and the complication rate were analyzed. RESULTS: Anastomotic stricture developed in 20 (40%) of the 50 patients undergoing primary repair for esophageal atresia. The occurrence of anastomotic stricture was related to anastomotic tension during esophageal surgical repair (p < 0.03). Young children required esophageal dilation at a mean age of 142 days (24-930 days). Stricture resolution occurred after a mean of 3.2 dilations (1-15) over an average period of 7.9 months (range: 0-30 months). Dilation was successful in 90% of the 20 patients. Seven patients required only one dilation. Perforation of the esophagus occurred in one case, and this severe complication led to the death of the child. Esophageal dilation was unsuccessful in two patients, who presented prolonged severe dysphagia. CONCLUSION: Anastomotic stricture following repair of esophageal atresia is connected with the length of the gap that has to be repaired, and tension during suture. Esophageal dilation by the Savary-Gaillard bougie technique is an effective method for treating esophageal stricture. Several dilations are usually needed before the disappearance of dysphagia.

Age Factors↗
PubMed2001

[Experimental study of changes in FiO2 during manual ventilation].

UNLABELLED: Discrepancies exist in the recommendations about the oxygen flow to deliver during manual ventilation. The aim of the present study was to determine the effects of ventilatory frequency (FR), inspiratory pressure (P) and oxygen flow on the concentration of the delivered oxygen (FiO2) to obtain FiO2 near 1. MATERIAL AND METHODS: Experimental study with self-inflating resuscitation bag (Ambu with oxygen reservoir) tested on a mono-compartmental test lung (resistant tube and elastic bag [Draeger]; characteristics: compliance = 0.6 mL/cmH2O; resistance = 85 cmH2O.L-1.s-1). Protocol 1: six neonatologists ventilated this model as if they were ventilating premature newborn infants with RDS at various ventilatory rates from 30 to 120 bpm and at various oxygen flows (from 2 to 12 L/min). Tidal volumes (Vt), inspiratory times (Ti), P and FiO2 were recorded continuously during the study. Protocol 2: a graduated manometer was added to visualize pressure. The same protocol was then applied. RESULTS: Protocol 1 (without visual control of the pressure): increase in oxygen flow delivered with the Ambu increases the FiO2 values (P < 0.0001); the higher the ventilatory frequency, the lower the FiO2 (P < 0.0001). The mean value of delivered FiO2 was related to the operator (extreme: 47-86%) (P < 0.001). Multivariate statistical analysis showed that O2 flow, ventilator rate and operator modulated independently the FiO2. Ti and Vt did not change the FiO2. Protocol 2 (with visual control of the pressure: the mean inflating pressures were less than those obtained without visual control of the pressure (26 vs 40 cmH2O respectively; P < 0.05). FiO2 was independent of O2 flow and ventilatory rate. CONCLUSIONS: A special device for continuous visual control of airway pressure is recommended during neonatal manual ventilation. It prevents ventilatory rate-induced FiO2 fluctuations and overdistention.

Equipment Design↗
PubMed2001

Effects of catecholamines on the pulmonary circulation in the ovine fetus.

High levels of circulating catecholamines are found in the fetus, and fetal stress and birth induce a marked surge in catecholamine secretion. Little is known about the role of catecholamines on the fetal pulmonary circulation. To determine the effects of catecholamines on the pulmonary vascular tone, we tested the hemodynamic response to norepinephrine and dopamine infusion in chronically prepared late-gestation fetal lambs. We found that norepinephrine infusion (0.5 microg. kg(-1). min(-1)) increased pulmonary artery pressure (PAP) by 10 +/- 1% (P < 0.01), left pulmonary artery blood flow by 73 +/- 14% (P < 0.01), and decreased pulmonary vascular resistance (PVR) by 33 +/- 6% (P < 0.01). The pulmonary vasodilator effect of norepinephrine was abolished after nitric oxide synthase inhibition. Dopamine infusion at 5 microg. kg(-1). min(-1) did not significantly change PVR. Conversely, dopamine infusion at 10 microg. kg(-1). min(-1) increased PAP (P < 0.01) and progressively increased PVR by 30 +/- 14% (P < 0.01). These results indicate that catecholamines may modulate basal pulmonary vascular tone in the ovine fetus. We speculate that catecholamines may play a significant role in the maintenance of the fetal pulmonary circulation and in mediating changes in the transitional pulmonary circulation.

Adrenergic alpha-Agonists↗
PubMed2000

[Congenital hernia of the diaphragm. A retrospective study of 123 cases recorded in the Neonatal Medicine Department, URHC in Lille between 1985 and 1996].

BACKGROUND: During the last ten years, new therapeutic strategies have been used in order to improve the management of congenital diaphragmatic hernia (CDH). CDH is associated with pulmonary hypoplasia, abnormal pulmonary vascular reactivity and pulmonary immaturity. Between 1985 and 1990, mechanical hyperventilation and early surgery were provided systematically. Since 1991, the management of CDH in our institution has involved a preoperative stabilization with exogenous surfactant replacement, gentle ventilation, high-frequency oscillation, nitric oxide or extracorporeal membrane oxygenation. PURPOSE: To analyse the impact of the new therapeutic strategy on the survival and outcome of newborns with CDH. METHODS: Retrospective review of all infants with CDH admitted to our institution from 1985 through 1996. Mortality and morbidity were compared between period I (1985-1990) and period II (1991-1996). RESULTS: Between 1985 and 1996, 123 neonates were admitted to our Neonatal Department. Nine of them had another severe congenital malformation and were excluded from the study. Survival was 23% (12/52) in period I and 56% (35/62) in period II (p < 0.001). In period II, complications were more frequent among survivors in whom an extracorporeal membrane oxygenation was required (13 infants): bronchopulmonary dysplasia 77% (10/13), gastroesophageal reflux 61% (8/13), and hypotrophy 61% (8/13). CONCLUSION: These data demonstrate a significant improvement in survival in CDH since the implementation of new therapeutic modalities. Nevertheless, a significant morbidity exists among the infants who survive a severe respiratory failure.

Bronchopulmonary Dysplasia↗
PubMed2000

Combined effects of inhaled nitric oxide (iNO) and oxidant agents on the production of methemoglobinemia in newborn piglets.

OBJECTIVE: To investigate the effects of the association of inhaled nitric oxide (iNO) and oxidant drugs (acetaminophen, phytomenadione, and EMLA cream) on methemoglobinemia during the neonatal period. DESIGN: Prospective, randomized, experimental study. SETTING: University Experimental Pharmacology laboratory. SUBJECTS: Sixty newborn piglets weighing 1.5-2.0 Kg. INTERVENTIONS: Twelve groups of five piglets were anaesthetized, mechanically ventilated, and studied for 3 hrs. Eight groups received iNO (40 ppm or 80 ppm) alone or in association with a single intravenous dose of acetaminophen (120 mg/kg propacetamol), phytomenadione (5 mg vitamin K1) or EMLA cream (2.5 g) applied to the ventral lower abdomen for 3 hrs. Three other groups received, respectively, acetaminophen, phytomenadione, or EMLA cream without iNO. The last group (control group) received neither drugs nor iNO. MEASUREMENTS AND MAIN RESULTS: Methemoglobinemia was measured before the beginning of each experiment, 30 mins later, and every hour for 3 hrs. There was no significant difference in methemoglobinemia at any time between groups receiving acetaminophen (0.90%+/-0.12%), phytomenadione (0.88%+/-0.11%), or EMLA cream alone (0.97%+/-0.11%) and the control group (0.92%+/-0.12%). At 3 hrs, methemoglobinemia was slightly but significantly increased in group receiving iNO alone (1.04%+/-0.17% at 40 ppm iNO and 1.14%+/-0.16% at 80 ppm iNO; p < .05). Conversely, methemoglobinemia increased as a function of time in groups in which iNO was associated to drug administration and was significantly greater than the control group at 3 hrs (80 ppm iNO + acetaminophen, 2.80%+/-0.47%; 80 ppm iNO + phytomenadione, 2.38%+/-0.45%; 80 ppm iNO + EMLA cream, 2.33%+/-046%; p < .001). CONCLUSIONS: These results demonstrate that if oxidant drugs (acetaminophen, phytomenadione, or EMLA cream) did not increase blood methemoglobinemia in neonatal piglets, their association with iNO caused an increase in methemoglobin. Special care should be taken to monitor methemoglobinemia when iNO is combined to such drugs in newborn infants.

Acetaminophen↗
PubMed1999

[Use of double-lumen umbilical vein catheters in a neonatal intensive care unit].

BACKGROUND: The aim of the study was to compare the success/failure rate and complications of insertion into the umbilical vein, of either double-lumen catheters (Charrière diameter 04, length 13 and 30 cm) or single-lumen catheters (Charrière diameter 05, length 40 cm) in a population of neonates admitted to a neonatal intensive care unit. The numbers of insertions of additional peripheral venous catheters were also compared. PATIENTS AND METHODS: The population was divided into two groups according to the severity of the respiratory failure. Group 1 (n = 52): normal hemodynamic parameters and moderate respiratory failure (FiO2 < 0.6): only single-lumen catheters were used. Group 2 (n = 56): low systemic pressure requiring vascular filling and/or inotropic drugs infusion and/or severe respiratory failure (FiO2 > 0.6): in this group, either single-lumen catheters or double-lumen catheters were inserted. RESULTS: The success rate of insertion of double-lumen catheters and of single-lumen catheters were similar (61% vs 71%: P = 0.7). Nineteen double-lumen catheters were inserted in the group 2. The average duration of double-lumen umbilical catheterization was not significantly different from simple-lumen catheterization (4.9 +/- 2.2 vs 4.6 +/- 2.2 days). Complications relating to the umbilical venous catheterization were uncommon: three catheter obstructions (two with single-lumen catheter, one with double-lumen catheters), two nosocomial infections (both with single-lumen catheter), one hydropericardium (with single-lumen catheter). In group 2, more peripheral venous catheters were required during the first 72 hours of life after insertion of single-lumen catheter than after insertion of double-lumen catheters (average number of peripheral venous catheters per infant: 1.6 +/- 0.83 vs 1 +/- 0.35 respectively; P < 0.01). CONCLUSION: Feasibility and complication rate of umbilical double-lumen catheters were similar to those of single-lumen catheters. The use of umbilical double-lumen catheters reduces the need of peripheral venous catheters.

Cardiotonic Agents↗
PubMed1999

[For or against the early use of nasal continuous positive pressure and exogenous surfactant in hyaline membrane disease. Physiopathologic arguments].

The use of nasal CPAP in the treatment of respiratory distress syndrome in very premature newborns follows pathophysiological basis. The authors emphasize the usefulness of nasal CPAP and surfactant in the treatment of respiratory distress syndrome. The aim of this strategy is to reduce alveolar atelectasis, thus reducing the incidence and the severity of respiratory distress syndrome, together with a possible reduction of the incidence of bronchopulmonary dysplasia.

Bronchopulmonary Dysplasia↗
PubMed1996

[Is Ambu ventilation of newborn infants a simple question of finger-touch?].

Insufflation pressures were measured during manual ventilation using a neonatal rebreathing bag (Ambu on a manikin. Maximal insufflation pressures were greater than that published or given by the manufacturer, theoretically limited to 30 cm of water at open valve, and that whatever the number of fingers used for the compression of the bag. These results indicate that Ambu ventilation, often mandatory for newborn resuscitation, does not simply rely upon the finger-touch of the operator and that it always has a risk of baro and/or volotraumatism.

Humans↗