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Gabriel Dimitriou

Publications and source records attributed to Gabriel Dimitriou.

12 recordsLinked to original sources
PubMed2007

Lung function and exhaled nitric oxide levels in infants developing chronic lung disease.

Chronic lung disease (CLD) is a common outcome of neonatal intensive care. To determine whether the results of serial exhaled nitric oxide (eNO) measurements during the perinatal period differed between infants who did and did not develop CLD. In addition, we wished to assess whether eNO results were more predictive of CLD development than lung function test results or readily available clinical data (gestational age and birthweight). The patients were 24 infants with a median gestational age of 27 (range 25-31) weeks. Measurements of eNO levels, functional residual capacity (FRC), and compliance of the respiratory system (CRS) were attempted on postnatal days 1, 3, 5, 7, 14, and 28 days. The 12 infants who developed CLD were of significantly lower birthweight and gestational age than the rest of the cohort; in addition, they had lower median FRC (P < 0.02) and CRS (P < 0.02) results, but not higher eNO levels, in the first week after birth. Construction of receiver operator characteristic (ROC) curves demonstrated that the CRS and FRC results on Day 3 were the best predictors of CLD development; the areas under the ROC curves were 0.94 and 0.91, respectively. Early lung function test results, but not eNO levels, are useful in predicting CLD development, but are not significantly better than birthweight.

Birth Weight↗
PubMed2006

A scoring system to predict chronic oxygen dependency.

INTRODUCTION: Chronic oxygen dependency (COD) is a common adverse outcome of very premature birth. It is, therefore, important to develop an accurate and simple predictive test to facilitate targeting of interventions to prevent COD. Our aim was to determine if a simple score based on respiratory support requirements predicted COD development. METHODS: A retrospective study of 136 infants, median gestation age (GA) 28 weeks (range: 23-33 weeks) and a prospective study of 75 infants, median GA 30 weeks (range: 23-32 weeks), were performed. The score was calculated by multiplying the inspired oxygen concentration by the level of respiratory support (mechanical ventilation: 2.5; continuous positive airway pressure: 1.5; nasal cannula or head box oxygen or air: 1.0). Scores were calculated on data from days 2 and 7, and their predictive ability compared to that of the maximum inspired oxygen concentration at those ages and (retrospective study) the results of lung volume measurement. RESULTS: Infants that were oxygen dependent at 28 days and 36 weeks post-menstrual age (PMA) had higher scores on days 2 (p<0.0001, p<0.0001, respectively) and 7 (p<0.0001, p<0.0001, respectively) than the non-oxygen dependent infants in both the retrospective and prospective cohorts. Construction of receiver operator characteristic curves demonstrated the score performed better than the inspired oxygen level and lung volume measurement results. A score on day 7 >0.323 had 95% specificity and 78% sensitivity in predicting COD at 28 days, and 80% specificity and 73% sensitivity in predicting COD at 36 weeks PMA. CONCLUSION: Chronic oxygen dependency can be predicted using a simple scoring system.

Bronchopulmonary Dysplasia↗
PubMed2005

Lung volumes in infants who had mild to moderate bronchopulmonary dysplasia.

"New" bronchopulmonary dysplasia (BPD) has been suggested to be a maldevelopment sequence with reduced alveolarisation of the lungs; affected infants then would be predicted to have low lung volumes. The aim of this study was to test that hypothesis by comparing the lung volumes of infants who had had mild-moderate BPD with those without BPD of similar postmenstrual age. Lung volumes of 17 infants who had mild-moderate BPD (oxygen dependent beyond 28 days, but not past term) (BPD infants) were compared to those of 17 infants without BPD (non-BPD infants). All were born at less than 33 weeks of gestation and studied at postmenstrual ages of 33 to 39 weeks. Lung volume was assessed by measurement of functional residual capacity (FRC). The BPD infants had lower lung volumes (median 19.1 ml/kg) than the non-BPD infants (median 26.5 ml/kg) (p = 0.0001). The BPD compared to the non-BPD infants were of greater postnatal age (p = 0.0003), born at a lower gestational age (p = 0.0001) and of lighter birthweight (p = 0.0001). Regression analysis, however, demonstrated that lung volume was significantly related to BPD status (p = 0.005), independently of postnatal age, birthweight and gestational age. It is concluded that the lower lung volumes of the infants who had had mild-moderate BPD support the hypothesis that new BPD is associated with poor alveolarisation.

Birth Weight↗
PubMed2005

Definitive surgical management of antenatally diagnosed exomphalos.

BACKGROUND/PURPOSE: The management of exomphalos is controversial with many centers in the United Kingdom and elsewhere advocating a conservative nonsurgical approach for the larger examples. Nevertheless, this approach is not without problems or complication. The aim of the study was to ascertain the outcome of all infants with an antenatally diagnosed exomphalos treated recently at our institution using a policy of aggressive abdominal wall closure. METHODS: This is a retrospective review of all infants with exomphalos treated from January 1995 to September 2002. RESULTS: There were 35 infants, all of whom underwent surgery. These were separated into 3 groups: group A (all exomphalos minor) underwent primary closure (n = 11), group B (exomphalos major) underwent primary closure (n = 13), and group C (exomphalos major) underwent staged closure involving a silo (n = 11). Infants in group C had a lower birth weight (P = .05) and were less mature (P = .06). They required longer periods of ventilation (P < .001), a longer hospital stay (P = .001), and a longer period to achieve full enteral feeds (P < .001). Overall survival was 34 (97%) of 35 infants. One premature infant who was born with a ruptured exomphalos sac (birth weight, 862 g) died of nonsurgical complications (sepsis and respiratory failure) early after the creation of a silo. CONCLUSIONS: An aggressive surgical approach in infants with exomphalos is a safe option resulting in effective abdominal wall closure. This requires a skilled multidisciplinary approach and possibly greater resources than other options.

Abdominal Wall↗
PubMed2004

Cerebral palsy in triplet pregnancies with and without iatrogenic reduction.

UNLABELLED: Iatrogenic fetal reduction is undertaken to try and improve the outcome of multiple pregnancies by reducing the rate of severe preterm delivery. In twin pregnancies, however, spontaneous death of one of the fetuses is associated with increased risk of cerebral palsy (CP) in the survivor. The aim of this study was to determine whether iatrogenic fetal reduction might also increase the prevalence of CP. The database of a tertiary fetal medicine unit was interrogated to identify women with trichorionic triplet pregnancies who had either given birth to three live infants or two live infants following selective fetal reduction. A questionnaire was sent to the women's general practitioners asking them to report whether any of the children had CP. The results of the questionnaire revealed that the CP prevalence (13.8 per 1000) of 72 children from trichorionic triplet pregnancies reduced to twins by selective termination was similar to that of 111 children from trichorionic triplet pregnancies with no loss (18 per 1000), but the pregnancies with selective termination delivered at a later gestation (P = 0.004). CONCLUSION: a lower cerebral palsy rate might have been expected in the pregnancies with selective termination given that they were delivered at a later gestational age; these data, therefore, emphasise the importance of further investigating the impact of selective reduction on the prevalence of cerebral palsy.

Cerebral Palsy↗
PubMed2003

Prediction of outcome from the chest radiograph appearance on day 7 of very prematurely born infants.

UNLABELLED: Our aim was to determine whether the chest radiograph appearance at 7 days predicted chronic lung disease development (oxygen dependency at 36 weeks post-menstrual age) or death before discharge and if it was a better predictor than readily available clinical data. Two consecutive studies were performed. In both, chest radiographs taken at 7 days for clinical purposes were assessed using a scoring system for the presence of fibrosis/interstitial shadows, cystic elements and hyperinflation and data were collected regarding gestational age, birth weight, use of antenatal steroids and post-natal surfactant and requirement for ventilation at 7 days. Oxygenation indices were calculated in the first study (study A) at 120 h and in the second (study B) at 168 h. In study A, there were 59 infants with a median gestational age of 26 weeks (range 24 to 28 weeks) and in study B, 40 infants with a median gestational age of 27 weeks (range 25-31 weeks). In both studies, infants who developed chronic lung disease had a significantly higher total chest radiograph score, with a higher score for fibrosis/interstitial shadowing than the rest of the cohort. Infants who died before discharge differed significantly from the rest with regard to significantly higher scores for cysts. In both studies, the areas under the receiver operator characteristic curves with regard to prediction of chronic lung disease were higher for the total chest radiograph score compared to those for readily available clinical data. CONCLUSION: In infants who require a chest radiograph for clinical purposes at 7 days, the chest radiograph appearance can facilitate prediction of outcome of infants born very prematurely.

Chronic Disease↗
PubMed2003

Diaphragmatic function in infants with surgically corrected anomalies.

Infants with surgically correctable anomalies, abdominal wall defects (AWD) or congenital diaphragmatic hernia (CDH) may have poor postnatal diaphragmatic function, because the low intra-abdominal pressure experienced by such patients in utero could result in impaired diaphragmatic development. Our objective was to compare postoperative diaphragmatic function of infants with CDH or AWD to that of gestational age-matched controls. Diaphragmatic function was assessed by measurement of the transdiaphragmatic pressure and maximum inspiratory pressure at the mouth generated during crying against an occlusion. In addition, the transdiaphragmatic pressure produced by unilateral and/or bilateral magnetic stimulation of the phrenic nerves (TwPdi) was examined. Lung volume was assessed by measurement of functional residual capacity (FRC) using a helium gas dilution technique. Ten infants with CDH, 26 with AWD infants (19 gastroschisis, seven exomphalos), and 36 gestational age-matched controls were studied. Compared with their matched controls, the eight CDH infants with left-sided defects had significantly lower left (p < 0.01) and right (p < 0.05) TwPdi and FRC (p < 0.01), and the gastroschisis infants, but not those with exomphalos, had significantly lower left and right TwPdi (p < 0.05). There were no significant differences in transdiaphragmatic pressure and maximum inspiratory pressure at the mouth between the CDH or AWD infants and the controls. Diaphragmatic function postoperatively is impaired in infants with CDH or gastroschisis.

Abdominal Wall↗
PubMed2003

Influence of maturation on infant diaphragm function assessed by magnetic stimulation of phrenic nerves.

Infant diaphragm function may be adversely affected in a variety of disorders and conditions. Key to establishing an accurate diagnosis are appropriate control data. The aim of this study was to determine the effect of maturation on diaphragm function, using a nonvolitional test. Diaphragm function was assessed by measuring the transdiaphragmatic pressure (Pdi) generated by magnetic stimulation of the phrenic nerves. Ballon catheters were positioned in the lower third of the esophagus and stomach. Esophageal (Pes) and gastric (Pgas) pressure changes were measured using differential pressure transducers. The pressure signals were amplified and displayed in real time on a computer (running Labview trade mark software) and Pdi derived by online subtraction of Pes from Pgas. Twenty-nine infants (14 born preterm), at a median gestational age of 37 (range, 25-42) weeks, were studied at a median postconceptional age (PCA) of 39 (range, 32-44) weeks. At time of measurement, none had respiratory problems or were hyperinflated (functional residual capacity ranged from 23-35 mL/kg). The preterm infants had significantly lower transdiaphragmatic pressures responses following median left (4.0, range 2.5-6.8 cmH(2)O vs. 4.8, range 2.8-7.2 cmH(2)O) and median right phrenic nerve stimulation (3.6, range 2.6-4.8 cmH(2)O vs. 4.3, range 2.7-6.8 cmH(2)O) (P < 0.05) than term infants. Following left and right phrenic nerve stimulation, Pdi correlated significantly with gestational age (r = 0.4, P < 0.05, and r = 0.4, P < 0.05, respectively) and PCA (r = 0.37, P = 0.05, and r = 0.56, P < 0.01, respectively). We conclude that gestational age at birth and postconceptional age at time of measurements must be taken into account when interpreting the results of infant diaphragm function tests.

Diaphragm↗
PubMed2002

Colloid infusion in the perinatal period and abnormal neurodevelopmental outcome in very low birth weight infants.

UNLABELLED: In very low birth weight (VLBW) infants, colloid infusion is associated with impaired perinatal lung function and increased oxygen dependency duration. The aim of this study was to determine whether perinatal colloid infusion was associated with abnormal neurodevelopmental outcome. All perinatal fluid input (crystalloid and colloid) given to VLBW infants entered into a randomised trial was recorded. At 1 and/or 2 years, the neurodevelopmental status of VLBW infants was routinely assessed. Of 131 survivors, median gestational age 27 weeks (range 23-33 weeks), 95 were seen at follow-up. Nineteen had abnormal neurodevelopmental outcome and differed significantly from the rest of the cohort with regard to their birth weight, magnitude of colloid infusion received and the proportions who had received postnatal steroids, suffered prolonged oxygen dependency or having had intracerebral haemorrhage/periventricular leucomalacia development. Regression analysis demonstrated that only colloid infusion related significantly to abnormal neurodevelopmental outcome independent of other variables. CONCLUSION: These data suggest that colloid infusion should be used with caution in the perinatal period.

Brain↗
PubMed2002

Diaphragmatic dysfunction after pediatric orthotopic liver transplantation.

BACKGROUND: Pediatric orthotopic liver transplantation (OLT) has a low mortality. Some children, however, have an adverse outcome defined as a prolonged ventilatory support requirement and protracted pediatric intensive care unit (PICU) stay. The aim of this study was to determine if that adverse outcome related to the child's condition pre-OLT and/or the development of a pleural effusion or diaphragmatic dysfunction. METHODS: The study included 210 children with a median age at transplantation of 45.5 months (range 0.2-252 months). Fourteen had undergone retransplantation. The duration of ventilatory support (intermittent positive pressure ventilation [IPPV]) and PICU admission and development of a pleural effusion and/or diaphragmatic dysfunction were documented for each child. The patients were divided into three groups according to whether they had acute liver failure (ALF), chronic liver disease at home (CHOM), or chronic liver failure sufficiently ill to be in the hospital awaiting transplantation (CHOSP). RESULTS: The 36 children with ALF were of similar age to the 138 CHOM and 36 CHOSP children but required longer IPPV (P<0.0001) and PICU stay (P<0.0001). Overall, 17 children developed diaphragmatic dysfunction and 138 pleural effusions; affected children required longer IPPV and PICU stay (P<0.01). Regression analysis demonstrated that diaphragmatic dysfunction, but not pleural effusion development, was associated with prolonged ventilation (P<0.01) and protracted PICU stay (P<0.05). Other risk factors were ALF (P<0.01), retransplantation (P<0.01), and young age (P<0.05). CONCLUSION: Diaphragmatic dysfunction adversely influences PICU morbidity after OLT. Early assessment of diaphragmatic function, and if necessary aggressive management, might improve outcome.

Adolescent↗
PubMed2002

Rescue high frequency oscillation and predictors of adverse neurodevelopmental outcome in preterm infants.

BACKGROUND: High frequency oscillation (HFO) is now frequently used as rescue support, but it has been suggested that as many as one-third of survivors have abnormal neurodevelopmental findings at follow-up. OBJECTIVE: To identify risk factors for adverse neurodevelopmental outcome at 1 and 2 years in very prematurely born patients, who, because of severe neonatal respiratory failure, had required transfer to high frequency oscillation (HFO). METHODS: A case control study was performed. Controls were supported by conventional mechanical ventilation (CMV) only and matched to HFO infants for gestational age. At 1 and 2 years, neurodevelopmental status was assessed in both groups. Abnormal neurodevelopmental outcome was diagnosed if infants had impairment with or without disability or a Griffiths developmental quotient of at least two standard deviations below the mean. PATIENTS: Fifty-six infants were studied, median gestation age of 28 weeks (range 23--31). RESULTS: At 2 years of age, a greater proportion of the HFO infants compared to the controls had an abnormal outcome (p<0.05). HFO infants with an abnormal outcome compared to those with a normal outcome had poorer oxygenation prior to transfer to HFO (p=0.05), but did not have a lower initial improvement in oxygenation or longer duration of hypocarbia on HFO. Logistic regression demonstrated adverse outcomes significantly related to HFO use and gestational age in the whole study population and to gestational age in the HFO infants. CONCLUSION: An initial response to HFO does not guarantee normal neurodevelopmental outcome. Rescue HFO in very immature infants should be used cautiously.

Case-Control Studies↗