Biomedical subjects

Ross R Haslam

Publications and source records attributed to Ross R Haslam.

6 recordsLinked to original sources

PubMed2007

Effect of omeprazole on acid gastroesophageal reflux and gastric acidity in preterm infants with pathological acid reflux.

INTRODUCTION: Proton pump inhibitor (PPI) therapy is increasingly being used to treat premature infants with gastroesophageal reflux disease (GERD); however, the efficacy of PPI on acid production in this population has yet to be assessed in this patient group. The aim of this study was to determine the effect of 0.7 mg/kg/d omeprazole on gastric acidity and acid gastroesophageal reflux in preterm infants with reflux symptoms and pathological acid reflux on 24-h pH probe. METHODS: A randomized, double blind, placebo-controlled, crossover design trial of omeprazole therapy was performed in 10 preterm infants (34-40 weeks postmenstrual age). Infants were given omeprazole for 7 d and then placebo for 7 d in randomized order. Twenty-four-hour esophageal and gastric pH monitoring was performed on days 7 and 14 of the trial. RESULTS: Compared to placebo, omeprazole therapy significantly reduced gastric acidity (%time pH <4, 54% vs 14%, P < 0.0005), esophageal acid exposure (%time pH <4, 19% vs 5%, P < 0.01) and number of acid GER episodes (119 vs 60 episodes, P < 0.05). CONCLUSIONS: Omeprazole is effective in reducing esophageal acid exposure in premature infants with pathological acid reflux on 24-h pH probe; however, the far more complex issues of safety and efficacy have yet to be addressed.

Anti-Ulcer Agents↗

PubMed2006

Neonatal respiratory distress syndrome after repeat exposure to antenatal corticosteroids: a randomised controlled trial.

BACKGROUND: The efficacy and safety of repeat doses of prenatal corticosteroids remains uncertain. Our aim was to establish whether repeat prenatal corticosteroids given to women at risk of preterm birth can reduce neonatal morbidity without harm. METHODS: In this hospital-based study, 982 women who remained at risk of preterm birth at less than 32 weeks' gestation, 7 or more days after receiving a first course of prenatal corticosteroids, were randomly assigned to receive a repeat intramuscular dose of either 11.4 mg betamethasone (as Celestone Chronodose), or saline placebo. This was repeated every week the woman remained undelivered, at less than 32 weeks' gestation, and at risk of preterm birth. Primary outcomes were occurrence and severity of neonatal respiratory distress syndrome, use and duration of oxygen and mechanical ventilation, and weight, length, and head circumference at birth and hospital discharge. Statistical analyses were on an intention to treat basis. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN48656428. FINDINGS: Fewer babies exposed to repeat corticosteroids had respiratory distress syndrome (33%vs 41%; relative risk 0.82, 95% CI 0.71-0.95, p=0.01) and fewer had severe lung disease (12%vs 20%; relative risk 0.60, 95% CI 0.46-0.79, p=0.0003) than those in the placebo group. In keeping with these benefits, babies exposed to repeat corticosteroids needed less oxygen therapy (p=0.03), and shorter duration of mechanical ventilation (p=0.01). Mean weight, length, and head circumference at birth and hospital discharge did not differ between treatment groups. Z-scores for weight (p=0.04) and head circumference (p=0.03) at birth were lower in the babies who received repeat corticosteroids although at the time of hospital discharge Z-scores did not differ between treatment groups (p=0.29 for weight, p=0.48 for head circumference). INTERPRETATION: Exposure to repeat doses of antenatal corticosteroids reduces neonatal morbidity. Pending long-term outcome results, the short-term benefits for the babies in our study support the use of repeat doses of corticosteroids in women who remain at risk of very preterm birth 7 or more days after an initial course.

Betamethasone↗

PubMed2006

Vitamins C and E and the risks of preeclampsia and perinatal complications.

BACKGROUND: Supplementation with antioxidant vitamins has been proposed to reduce the risk of preeclampsia and perinatal complications, but the effects of this intervention are uncertain. METHODS: We conducted a multicenter, randomized trial of nulliparous women between 14 and 22 weeks of gestation. Women were assigned to daily supplementation with 1000 mg of vitamin C and 400 IU of vitamin E or placebo (microcrystalline cellulose) until delivery. Primary outcomes were the risks of maternal preeclampsia, death or serious outcomes in the infants (on the basis of definitions used by the Australian and New Zealand Neonatal Network), and delivering an infant whose birth weight was below the 10th percentile for gestational age. RESULTS: Of the 1877 women enrolled in the study, 935 were randomly assigned to the vitamin group and 942 to the placebo group. Baseline characteristics of the two groups were similar. There were no significant differences between the vitamin and placebo groups in the risk of preeclampsia (6.0 percent and 5.0 percent, respectively; relative risk, 1.20; 95 percent confidence interval, 0.82 to 1.75), death or serious outcomes in the infant (9.5 percent and 12.1 percent; relative risk, 0.79; 95 percent confidence interval, 0.61 to 1.02), or having an infant with a birth weight below the 10th percentile for gestational age (8.7 percent and 9.9 percent; relative risk, 0.87; 95 percent confidence interval, 0.66 to 1.16). CONCLUSIONS: Supplementation with vitamins C and E during pregnancy does not reduce the risk of preeclampsia in nulliparous women, the risk of intrauterine growth restriction, or the risk of death or other serious outcomes in their infants. (Controlledtrials.com number, ISRCTN00416244.).

Adult↗

PubMed2006

Neonatal adrenal function after repeat dose prenatal corticosteroids: a randomized controlled trial.

OBJECTIVE: Do repeat prenatal corticosteroids suppress neonatal cortisol concentrations? STUDY DESIGN: Randomized controlled trial of women given weekly repeat corticosteroids or saline placebo, while at risk of preterm birth, until 32 weeks' gestation. RESULTS: Cord serum cortisol concentrations in infants exposed to repeat corticosteroids were similar compared with infants exposed to a single course of corticosteroids (mean difference -26 nmol/L (95% CI -57, 5 nmol/L, P = .10), as were prestress salivary cortisol concentrations on day 3 (median 16.5 vs 15.3 nmol/L, P = .96). The adrenal response to a stressor on day 3 was lower in the repeat corticosteroid group compared with the single course group (median 11.9 vs 21.4 nmol/L, P = .02). Cortisol concentrations were lower in the repeat corticosteroid group on day 7 (median 11.7 vs 18.2 nmol/L, P = .04), but not on days 14 and 21. CONCLUSION: The short- or long-term clinical impact, if any, of these changes in adrenal function needs to be determined.

Adrenal Glands↗

PubMed2004

Paradoxical impact of body positioning on gastroesophageal reflux and gastric emptying in the premature neonate.

OBJECTIVES: To combine manometry and impedance to characterize the mechanisms of gastroesophageal reflux (GER) and to explore their relation to the rate of gastric emptying (GE) and body position. STUDY DESIGN: Ten healthy preterm infants (35 to 37 weeks' postmenstrual age) were studied with the use of a micromanometric/impedance assembly. Episodes of GER were identified by impedance, and the mechanism(s) of GER triggering and GER clearance were characterized. GE was determined with a C13Na-octanoate breath test. RESULTS: Gastroesophageal reflux episodes (n=89) were recorded, consisting of 74% liquid, 14% gas, and 12% mixed. Transient lower esophageal sphincter relaxation (TLESR) was the predominant mechanism of reflux, triggering 83% of GER. Of 92 TLESRs recorded, 27% were not associated with reflux. Infants studied in the right lateral position had significantly (P <.01) more GER, a higher proportion of liquid GER (P <.05), and faster GE (P <.005) when compared with infants studied in the left lateral position. CONCLUSIONS: In healthy preterm infants, GER is predominantly liquid in nature. Right-side positioning is associated with increased triggering of TLESR and GER despite accelerating GE.

Electric Impedance↗

PubMed2003

Effect of magnesium sulfate given for neuroprotection before preterm birth: a randomized controlled trial.

CONTEXT: Prenatal magnesium sulfate may reduce the risk of cerebral palsy or death in very preterm infants. OBJECTIVE: To determine the effectiveness of magnesium sulfate given for neuroprotection to women at risk of preterm birth before 30 weeks' gestation in preventing pediatric mortality and cerebral palsy. DESIGN, SETTING, AND PATIENTS: Randomized controlled trial at 16 tertiary hospitals in Australia and New Zealand with stratification by center and multiple pregnancy. A total of 1062 women with fetuses younger than 30 weeks' gestation for whom birth was planned or expected within 24 hours were enrolled from February 1996 to September 2000 with follow-up of surviving children at a corrected age of 2 years. INTERVENTIONS: Women were randomly assigned to receive a loading infusion of 8 mL (4 g [16 mmol] of 0.5 g/mL of magnesium sulfate solution or isotonic sodium chloride solution [0.9%]) for 20 minutes followed by a maintenance infusion of 2 mL/h for up to 24 hours. MAIN OUTCOME MEASURES: Rates of total pediatric mortality, cerebral palsy, and the combined outcome of death or cerebral palsy at a corrected age of 2 years. RESULTS: Data were analyzed for 1047 (99%) 2-year survivors. Total pediatric mortality (13.8% vs 17.1%; relative risk [RR], 0.83; 95% confidence interval [CI], 0.64-1.09), cerebral palsy in survivors (6.8% vs 8.2%; RR, 0.83; 95% CI, 0.54-1.27), and combined death or cerebral palsy (19.8% vs 24.0%; RR, 0.83; 95% CI, 0.66-1.03) were less frequent for infants exposed to magnesium sulfate, but none of the differences were statistically significant. Substantial gross motor dysfunction (3.4% vs 6.6%; RR, 0.51; 95% CI, 0.29-0.91) and combined death or substantial gross motor dysfunction (17.0% vs 22.7%; RR, 0.75; 95% CI, 0.59-0.96) were significantly reduced in the magnesium group. CONCLUSIONS: Magnesium sulfate given to women immediately before very preterm birth may improve important pediatric outcomes. No serious harmful effects were seen.

Cerebral Palsy↗