Objective-To compare respiratory compliance (Crs) and functional residual capacity (FRC) in infants randomized to a rescue course of antenatal steroids (AS) versus placebo.Study Design-Randomized, double-blinded trial. Pregnant women ≥ 14 days after initial AS were randomized to rescue AS or placebo. The primary outcomes were measurements of Crs and FRC. This study is registered with clinicaltrials.gov [NCT00669383].Results-44 mothers (56 babies) received rescue AS and 41 mothers (57 babies) received placebo. There was no significant difference in birth weight, or head circumference. Infants in the rescue group had an increased Crs (1.21 versus 1.01 mL/cm H 2 O/kg; adjusted 95% CI 0.01, 0.49; p =0.0433) compared to placebo. 13% in the rescue versus 29% in the placebo group required ≥ 30% oxygen (p <0.05). Patients delivered at ≤ 34 weeks had greater pulmonary benefits.Conclusion-Infants randomized to rescue AS have a significantly increased Crs compared to placebo.

Studies in preterm animal models have shown that antenatal corticosteroids enhance lung maturation by improving a variety of physiologic variables, including lung volumes. Changes in lung volume of preterm infants treated with a full course of antenatal steroids have not been investigated. We hypothesized that a full course of antenatal steroids would significantly increase functional residual capacity (FRC) in treated vs. untreated preterm infants. The objective of our study was to compare FRC and respiratory mechanics in steroid treated vs. untreated preterm infants. FRC and passive respiratory mechanics were prospectively studied within 36 hr of life in 20 infants (25-34 weeks of gestation) who had received a full course of antenatal steroids and in 20 matched untreated preterm infants. FRC was measured with the nitrogen washout method, and respiratory mechanics with the single-breath occlusion technique. Preterm infants who received steroids (n = 20; mean birth weight = 1,230 g; gestational age = 28.8 weeks) had a significantly higher FRC (29.5 vs. 19.3 mL/kg; P < 0.001) than untreated infants (n = 20; birth weight = 1,202 g; gestational age = 28.5 weeks). Passive respiratory system compliance was also increased in treated vs. untreated infants (P < 0.05). In conclusion, FRC and passive respiratory system compliance were significantly improved in preterm infants (25-34 weeks gestation) treated with a full course of antenatal steroids, compared to matched untreated infants. Although this study was not randomized, it confirms that antenatal steroids have important effects on pulmonary function that may contribute to a decreased risk of respiratory distress syndrome in treated preterm infants.

Our results demonstrate that weekly repetitive courses of AS do not significantly increase FRC or respiratory compliance in preterm infants when compared with a single remote course of steroids given at a mean gestational age of 29 weeks.

We previously reported on a 7-day course of dexamethasone starting at 0.5 mg/kg/day in intubated very low birth weight (VLBW) infants, 7-14 days of age, with increased dynamic pulmonary compliance and decreased bronchopulmonary dysplasia (BPD). The effect of low-dose dexamethasone on functional residual capacity (FRC) in VLBW infants is unknown. The objective of this study was to compare the effect of two regimens of moderately early dexamethasone on FRC and passive respiratory compliance (Crs) in VLBW infants at risk for BPD. Sixty-two intubated VLBW infants were randomized (double-blinded) at 7-21 days of age; 29 patients (mean birth weight, 839 g) received "high" dose dexamethasone (0.5 mg/kg/day for 3 days, 0.25 mg/kg/day for 3 days, and 0.1 mg/kg/day on day 7, total dose of 2.35 mg/kg), and 33 infants (mean birth weight, 830 g) received "low-dose" dexamethasone (0.2 mg/kg/day for 3 days and 0.1 mg/kg/day for 4 days, total dose of 1 mg/kg). FRC and Crs were measured with the nitrogen washout technique and single breath occlusion technique, before and on days 2, 5, and 7 of therapy. Clinical outcome and early neurodevelopmental follow-up were evaluated. FRC significantly increased in the high-dose (19.3 ml/kg at baseline to 34 ml/kg on day 7; P < 0.001) and low-dose (18.1 ml/kg at baseline to 30.3 ml/kg on day 7; P < 0.001) dexamethasone groups when compared to baseline. There was a significant increase in Crs and a decrease in FiO2 within each group. The improvements in FRC and Crs were comparable between groups, and specific compliances (Crs/FRC) were not different. There were no significant differences in other clinical outcome parameters, including BPD and neurodevelopmental outcome. In conclusion, there are significant increases in FRC during a 7-day course of moderately early dexamethasone in VLBW infants. The lower total dose (1 mg/kg) appears as effective as the higher total dose of dexamethasone (2.35 mg/kg) in increasing FRC. Comparable significant increases in Crs were observed in both groups of infants. Additional long-term follow-up is underway.

No abstract

No abstract

Abstract. Diarrhea history questionnaires were administered to 369 U.S. military volunteers before and after deployment to Thailand. Additionally, blood samples obtained from a subset of 221 volunteers 1-3 weeks previously and 3-4 weeks after their deployment were tested by enzyme-linked immunosorbent assay for immunoglobulin A to Campylobacter jejuni. Stool samples from personnel (including volunteers) contracting diarrhea in Thailand were cultured for enteric pathogens. Overall, 35.2% (130 of 369) of questionnaire respondents reported one or more diarrhea episodes during their trip. Volunteers with pretravel anti-C. jejuni reciprocal titers Յ 450 were 1.6 times as likely to have had diarrhea during their stay in Thailand compared with those with pretravel titers Ͼ 450 (39.7% versus 25.3%; P ϭ 0.05). The symptomatic seroconversion, or attributable Campylobacter diarrhea attack rate, for the 1-month exercise was 12.7% (28 of 221). The symptomatic seroconversion rate in nonimmune (titer Յ 450) volunteers was 17.1%, whereas that in immune volunteers was only 4.0% (P ϭ 0.002). Campylobacter jejuni or C. coli were recovered from 32.9% (56 of 170) of stool samples cultured and were the most commonly identified enteropathogens. Campylobacter diarrhea was associated with elevated temperatures, fecal red cells, and fecal white blood cells. The results of this study show that Campylobacter continues to represent a significant health threat to Western travelers to Thailand, but many of these travelers have preexisting Campylobacter immunity that protects them from clinically significant Campylobacter enteritis.

No abstract