Search PubMed⌕ Search

Biomedical subjects

C J Morley

Publications and source records attributed to C J Morley.

At least 37 records · Page 2Linked to original sources
PubMed2000

Prophylactic versus selective use of surfactant for preventing morbidity and mortality in preterm infants.

BACKGROUND: This section is under preparation and will be included in the next issue. OBJECTIVES: To compare the effect of prophylactic surfactant administration to surfactant treatment of established respiratory distress syndrome in premature infants. SEARCH STRATEGY: Searches were made of the Oxford Database of Perinatal Trials, Medline (MeSH terms: pulmonary surfactant; limits: age groups, newborn infants), previous reviews including cross-references, abstracts, conference and symposia proceedings, expert informants, and journal handsearching in the English language. SELECTION CRITERIA: Randomized controlled trials which compared the effects of prophylactic surfactant administration to surfactant treatment of established respiratory distress syndrome in premature infants were included in the analysis. DATA COLLECTION AND ANALYSIS: Data regarding clinical outcomes including the incidence of pneumothorax, pulmonary interstitial emphysema, patent ductus arteriosus, necrotizing enterocolitis, intraventricular hemorrhage (any grade and severe intraventricular hemorrhage), bronchopulmonary dysplasia, mortality, bronchopulmonary dysplasia or death, and retinopathy of prematurity were excerpted from the reports of the clinical trials by the reviewers. Data analysis was done in accordance with the standards of the Cochrane Neonatal Review Group. MAIN RESULTS: The majority of included studies noted an initial improvement in the respiratory status and a decrease in the incidence of respiratory distress syndrome in infants who received prophylactic surfactant. The meta-analysis supports a decrease in the incidence of pneumothorax, a decrease in the incidence of pulmonary interstitial emphysema, a decrease in the incidence of mortality and a decrease in the incidence of bronchopulmonary dysplasia or death associated with prophylactic administration of surfactant. No significant untoward effects of prophylactic surfactant administration are noted. REVIEWER'S CONCLUSIONS: Prophylactic surfactant administration to infants judged to be at risk of developing respiratory distress syndrome (intubated infants less than 30-32 weeks gestation) has been demonstrated to improve clinical outcome. Infants who receive prophylactic surfactant have a decreased incidence of pneumothorax, a decreased incidence of pulmonary interstitial emphysema and a decreased incidence of mortality. However, it remains unclear exactly which criteria should be used to judge "at risk" infants who would require prophylactic surfactant administration.

Humans↗
PubMed2000

The effect of draw-up volume on the accuracy of electrolyte measurements from neonatal arterial lines.

OBJECTIVES: Contamination by infusate of blood samples withdrawn from arterial lines has been recognized but not well documented for neonates. The aim of this study was to investigate, using in vitro and in vivo studies, the effects of different draw-up volumes (withdrawn from the line prior to the sample being taken) on the concentration of sodium. METHODS: In-vitro study: The tip of an umbilical artery catheter (dead space 0.6 mL), infused with half normal saline containing 1 unit/mL of heparin was placed in a beaker of normal saline. The line was flushed with 1 mL of this infusate just before each sample was taken. Volumes from 0.5 mL to 2.0 mL of infusate/normal saline were withdrawn in 0.1 mL increments from a three-way tap and discarded. A sample was then taken from the line into a blood gas syringe for analysis of the sodium concentration by the 860 Blood Gas Analyzer (Chiron Diagnostics, Bayer, Scoresby). Control samples were taken from the beaker. In-vivo study: A 22 gauge intravenous catheter was inserted into a vein of an adult male volunteer. The dead space was also 0.6 mL. The line was flushed with 5 mL of half-normal saline immediately before sampling. Draw-up volumes of 0.6, 0.9, 1.3, and 1.6 mL were withdrawn and discarded. 10 mL was used as a control. A 0.5-mL blood sample was then taken and the electrolyte concentrations analysed immediately. RESULTS: In-vitro: A minimum draw-up volume of 1.3 mL was required before the sodium concentration was not significantly different from the control samples. In-vivo: A minimum draw-up volume of 1.6 mL was required before the sodium concentration was not significantly different from the control samples. There were similar trends in the effect of draw-up volume for glucose, calcium, potassium, chloride and lactate. CONCLUSION: : A minimum volume of 1.6 mL should be withdrawn from neonatal arterial lines (dead space 0.6 mL) before taking blood for analysis.

Adult↗
PubMed2000

Overcoming surfactant inhibition with polymers.

Inhibition of the function of pulmonary surfactant in the alveolar space is an important element of the pathophysiology of many lung diseases, including meconium aspiration syndrome, pneumonia and acute respiratory distress syndrome. The known mechanisms by which surfactant dysfunction occurs are (a) competitive inhibition of phospholipid entry into the surface monolayer (e.g. by plasma proteins), and (b) infiltration and destabilization of the surface film by extraneous lipids (e.g. meconium-derived free fatty acids). Recent data suggest that addition of non-ionic polymers such as dextran and polyethylene glycol to surfactant mixtures may significantly improve resistance to inhibition. Polymers have been found to neutralize the effects of several different inhibitors, and can produce near-complete restoration of surfactant function. The anti-inhibitory properties of polymers, and their possible role as an adjunct to surfactant therapy, deserve further exploration.

Humans↗
PubMed2000

Bacterial colonization of toys in neonatal intensive care cots.

OBJECTIVES: To investigate the bacteria and fungi contaminating toys in neonatal intensive care unit (NICU) cots, the colonization rates, and factors that influence them. METHODS: A cross-sectional, longitudinal bacteriologic survey of all toys in the cots of infants in an NICU. All the toys in an infant's cot were cultured weekly for 4 weeks. Data were collected on the infant's postnatal age, the type of cot, whether humidity was added, characteristics of the toy, and any infant infections. RESULTS: Over the 4-week period, there were 86 cultures from 34 toys of 19 infants. Bacteria were grown from 84/86 (98%): 84 of the cultures grew coagulase-negative Staphylococcus, 50 Micrococcus sp, 21 Bacillus sp, 13 methicillin-resistant Staphylococcus aureus, 12 diphtheroids, 4 group B streptococcus, 3 S aureus, 3 nonhemolytic streptococci, 3 group D streptococci, 4 alpha-hemolytic streptococci, and 2 coliforms. None grew fungi. The colonization rate did not differ with cot type, presence of humidity, size of the toy, toy fiber length, or the fluffiness score. Eight (42%) of the infants had positive blood culture results and 5/8 of the isolates (63%) were of the same type as that colonizing their corresponding toy. IMPLICATIONS: With time, all the toys in NICU cots became colonized with bacteria. Many were potentially pathogenic. Toys may be reservoirs for potential infantile nosocomial sepsis. infant, newborn, toys, infection, neonatal intensive care.

Australia↗
PubMed1999

Is sudden infant death syndrome still more common in very low birthweight infants in the 1990s?

OBJECTIVE: To determine the rate of sudden infant death syndrome (SIDS) in very low birthweight children (VLBW) relative to children with low (LBW) and normal birthweights. DESIGN, SETTING AND SUBJECTS: Cohort study of consecutive live births in Victoria, 1993-1997 inclusive. MAIN OUTCOME MEASURES: All sudden unexpected deaths in early childhood over this five-year period; all deaths from SIDS (defined as a sudden unexpected death without a definite pathological explanation); and the proportion of SIDS in live births in three birthweight subgroups (VLBW, 500-1499 g; LBW, 1500-2499 g; and normal birthweight, > 2499 g). RESULTS: There were 316,028 live births (with known birthweight) in Victoria over the five-year period; 224 (0.71 per 1000 live births) died unexpectedly. In 10 of these deaths there was a definite pathological explanation, giving a rate of SIDS of 0.68 per 1000 live births. The rate of SIDS in VLBW children was 2.52 per 1000 live births, lower than the rate reported before the 1990s. The rate of SIDS in VLBW children was not significantly different from the rate in LBW children of 1.98 per 1000 live births (difference per 1000 live births, 0.53; 95% CI, -1.45 to 2.52), but was significantly higher than the rate in normal birthweight children of 0.59 per 1000 live births (difference per 1000 live births, 1.93; 95% CI, 0.06-3.79). CONCLUSIONS: The rate of SIDS in VLBW children has fallen in the 1990s, along with the overall fall in the rate of SIDS, but remains higher than that in normal birthweight children.

Humans↗
PubMed1999

Continuous neonatal blood gas monitoring using a multiparameter intra-arterial sensor.

AIMS: To compare arterial blood gas (ABG) readings obtained with a multiparameter intra-arterial sensor with those from an ABG analyser. METHODS: An MPIAS with the ability to measure continuously pH, PaCO2, and PaO2 was introduced via an umbilical arterial catheter in 27 neonates requiring intensive care. They underwent 3260 hours of MPIAS monitoring, during which 753 ABG readings were performed. RESULTS: Overall bias (mean difference: MPIAS-ABG) and precision (standard deviation of differences) values were: -0.002 and 0.022, respectively, for pH; +0.26 and 0.52 for PaCO2 (kPa); and -0.19 and 0.99 for PaO2 (kPa). This gave 95% limits of agreement as: -0.047 to +0.042 for pH, -0.76 to +1.28 kPa for PaCO2, and -2.13 to +1.75 kDa for PaO2. For each variable, precision across readings from the same individual was better than overall precision for all data. No complications related to the use of the catheter were observed. CONCLUSIONS: Continuous MPIAS ABG monitoring is an exciting development, with the potential to reduce blood transfusions and improve ABG homeostasis.

Blood Gas Analysis↗
PubMed1998

A case of kwashiorkor in the UK.

A case of kwashiorkor in a British child of Caucasian origin is described. The 5-year-old boy was referred to hospital for investigation of a persistent anaemia, but on examination was found to have classical features of kwashiorkor. He was stunted with both height and weight below the fifth centile and had mild pitting oedema in both legs. His hair was pale and easily pluckable and a soft liver edge was palpable. Plasma albumin concentration was 16 g/l and the plasma amino acid pattern, which revealed markedly reduced levels of essential but normal to high non-essential amino acids, was similar to that described in kwashiorkor in Uganda. A dietary history revealed that for about 2 years the child's diet had contained very little protein but adequate energy and had been supplemented with multivitamin pills. There was no evidence of other pathology, neglect or abuse and the child responded rapidly to refeeding with a balanced diet.

Amino Acids↗
PubMed1998

Infant Flow Driver or single prong nasal continuous positive airway pressure: short-term physiological effects.

The effectiveness of single prong nasal continuous positive airway pressure (CPAP) was compared with the Infant Flow Driver (IFD) in a crossover study in 20 neonates treated with > or = 30% oxygen by nasal CPAP. They were randomized to the device used at the start of the study. Each infant was studied for four consecutive 2-h periods alternating between single prong nasal CPAP and the IFD. The FiO2 from the IFD read 0.02 higher than the same setting on the ventilators used for single prong nasal CPAP. The IFD improved the mean (95% CI) of the FiO2 by 0.05 (0.02-0.08), p = 0.008. Taking into account the systematic error in the FiO2 between the devices the real mean improvement in FiO2 produced by the IFD was 0.03 (-0.005 to 0.06), p=0.09. There were no significant differences in respiratory rate, heart rate, blood pressure or comfort score of infants during periods of single nasal prong CPAP compared with periods on the IFD.

Cross-Sectional Studies↗
PubMed1995

Changes in oxygenation and heart rate after administration of artificial surfactant (ALEC) to preterm infants.

To determine if changes in oxygenation and heart rate occur after surfactant, changes in these variables were recorded continuously for 15 minutes before, during, and 15 minutes after the administration of the artificial surfactant ALEC to 21 preterm infants ventilated for respiratory distress syndrome. Median (range) birth weight and gestation were 1199 (561-2680) g and 28 (21-43) weeks, respectively. The mean (SD) time taken for administration was 17.6 (3.8) seconds. No clinically important changes resulted from the administration of ALEC in the mean (SD) values for oxygen saturation (before 91.3 (3.4)%, during 90.7 (3.2)%, after 90.4 (3.7)% and heart rate (before 143 (15), during 138 (17), after 142 (16)). The maximum change in mean arterial oxygen saturation (SaO2) was a fall of 4.8%.

Heart Rate↗
PubMed1994

Use of Baby Check to assess the severity of illness in babies attending a clinic in The Gambia.

Baby Check is a systematic way of grading the severity of illness in infants. We studied its usefulness for assessing 53 infants presenting to a clinic in a West African village. Their ages ranged from 2 weeks to 7 months. The Baby Check scores ranged from 0 to 30. Forty-four infants were considered by the doctors to be well or mildly ill, 41 of these had scores below 9. The three infants with higher scores had symptoms and signs suggesting they were more than mildly ill. Nine infants were considered to be moderately ill. Their scores ranged from 4 to 30. The babies with the low scores had few symptoms and diagnoses suggesting they were only mildly ill. The babies with the highest scores all had diagnoses requiring medical attention. This pilot study of Baby Check in a developing country suggests that its use by health workers could increase the accuracy with which babies are referred for a medical opinion, and be a valuable tool for the identification of such infants in a busy clinic.

Female↗
PubMed1994

Computerised determination of spontaneous inspiratory and expiratory times in premature neonates during intermittent positive pressure ventilation. I: A new technique.

A pneumatic capsule applied to the sub-xiphisternum provides a signal of spontaneous respiratory effort. Purpose-written software analyses this waveform to determine spontaneous inspiratory and expiratory times. Algorithms reject artefacts. The computerised system allows continuous measurement of spontaneous inspiratory and expiratory times to be made during intermittent positive pressure ventilation. The accuracy of the system was measured in 17 infants ventilated for respiratory distress syndrome: median (range) gestation and birth weight were 31 (25-38) weeks and 1195 (506-3260) g. The new technique can measure inspiratory time of individual breaths with a mean error of 5.4% and expiratory time with a mean error of 1.6%.

Humans↗
PubMed1994

Computerised determination of spontaneous inspiratory and expiratory times in premature neonates during intermittent positive pressure ventilation. II: Results from 20 babies.

Twenty premature infants ventilated for respiratory distress syndrome (RDS) were studied using a new computerised technique to determine spontaneous inspiratory and expiratory times. The technique is continuous and non-invasive. Infants were studied during intermittent positive pressure ventilation for periods of up to 45 minutes. Median birth weight and gestation were 1477 g and 30 weeks. The median number of breaths analysed for each baby was 925. The median (range) for spontaneous inspiratory time was 0.30 (0.26 to 0.34) seconds and for spontaneous expiratory time it was 0.46 (0.34 to 0.66) seconds. The spontaneous inspiratory and expiratory times were different from the ventilator settings.

Humans↗