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1.
BackgroundAs measurement of arterial oxygen saturation (SpO2) is common in the delivery room, target SpO2 ranges allow clinicians to titrate oxygen therapy for preterm infants in order to achieve saturation levels similar to those seen in normal term infants in the first minutes of life. However, the influence of the onset of ventilation and the timing of cord clamping on systemic and cerebral oxygenation is not known.AimWe investigated whether the initiation of ventilation, prior to, or after umbilical cord clamping, altered systemic and cerebral oxygenation in preterm lambs.MethodsSystemic and cerebral blood-flows, pressures and peripheral SpO2 and regional cerebral tissue oxygenation (SctO2) were measured continuously in apnoeic preterm lambs (126±1 day gestation). Positive pressure ventilation was initiated either 1) prior to umbilical cord clamping, or 2) after umbilical cord clamping. Lambs were monitored intensively prior to intervention, and for 10 minutes following umbilical cord clamping.ResultsClamping the umbilical cord prior to ventilation resulted in a rapid decrease in SpO2 and SctO2, and an increase in arterial pressure, cerebral blood flow and cerebral oxygen extraction. Ventilation restored oxygenation and haemodynamics by 5–6 minutes. No such disturbances in peripheral or cerebral oxygenation and haemodynamics were observed when ventilation was initiated prior to cord clamping.ConclusionThe establishment of ventilation prior to umbilical cord clamping facilitated a smooth transition to systemic and cerebral oxygenation following birth. SpO2 nomograms may need to be re-evaluated to reflect physiological management of preterm infants in the delivery room.  相似文献   

2.
Two hours after birth 30 normal infants had a fall in blood glucose of 20·6 mg/100 ml and a rise of plasma pancreatic glucagon of 50·7 pg/ml. Fifteen infants of diabetic mothers treated with insulin had a much greater fall in blood glucose of 77·5 mg/100 ml and a smaller rise of glucagon of 20·9 pg/ml. By comparison 14 small-for-dates infants, who are also prone to hypoglycaemia, had a blood glucose fall of 32·8 mg/100 ml and a larger rise of pancreatic glucagon of 96·0 pg/ml. It is suggested that the impaired pancreatic glucagon rise in the infants of diabetic mothers may be a significant factor in their hypoglycaemia.  相似文献   

3.

Background

The relationship between histological chorioamnionitis and haematological and biochemical markers in mothers and infants at delivery, and in infants postnatally, is incompletely characterised. These markers are widely used in the diagnosis of maternal and neonatal infection. Our objective was to investigate the effects of histological chorioamnionitis (HCA) on haematological and biochemical inflammatory markers in mothers and infants at delivery, and in infants post-delivery.

Methods

Two hundred and forty seven mothers, delivering 325 infants, were recruited at the only tertiary perinatal centre in Western Australia. Placentae were assessed for evidence of HCA using a semi-quantitative scoring system. Maternal high sensitivity C-reactive protein (hsCRP), procalcitonin, and umbilical cord hsCRP, procalcitonin, white cell count and absolute neutrophil count were measured at delivery. In infants where sepsis was clinically suspected, postnatal CRP, white cell count and absolute neutrophil count were measured up to 48 hours of age. The effect of HCA on maternal, cord and neonatal markers was evaluated by multivariable regression analysis.

Results

The median gestational age was 34 weeks and HCA was present in 26 of 247 (10.5%) placentae. Mothers whose pregnancies were complicated by HCA had higher hsCRP (median 26 (range 2–107) versus 5.6 (0–108) mg/L; P<0.001). Histological chorioamnionitis was associated with higher umbilical cord hsCRP (75th percentile 2.91 mg/L (range 0–63.9) versus 75th percentile 0 mg/L (0–45.6); P<0.001) and procalcitonin (median 0.293 (range 0.05–27.37) versus median 0.064 (range 0.01–5.24) ug/L; P<0.001), with a sustained increase in neonatal absolute neutrophil count (median 4.5 (0.1–26.4)×109/L versus 3.0 (0.1–17.8)×109/L), and CRP up to 48 hours post-partum (median 10 versus 6.5 mg/L) (P<0.05 for each).

Conclusion

Histological chorioamnionitis is associated with modest systemic inflammation in maternal and cord blood. These systemic changes may increase postnatally, potentially undermining their utility in the diagnosis of early-onset neonatal infection.  相似文献   

4.
Ventolin (salbutamol) and Medihaler-Duo (isoprenaline/phenylephrine combination) standard pressurized inhalers were used to administer doses of two or six “puffs” to 16 patients with known reversible airways obstruction. The doses were administered in random order over two days. Both the Ventolin and Medihaler-Duo inhalers substantially increased FEV1, but in the doses used salbutamol was more effective than isoprenaline/phenylephrine (P < 0·01). There was no significant difference between two and six puffs of salbutamol, though there seemed to be an advantage of six puffs of isoprenaline/phenylephrine over two puffs (P < 0·05). Adrenaline (1/1,000) 0·5 ml and atropine 0·6 mg produced similar increases in FEV1 to those produced by salbutamol.The Pao2 fell more than 5 mm Hg in three patients after salbutamol and in three after isoprenaline/phenylephrine. There was no significant fall in mean Pao2 in any of the treatment groups. It is concluded that the Ventolin inhalant, administered in the conventional dose of two puffs, is as effective a bronchodilator as subcutaneous adrenaline and atropine, is more effective than the Medihaler-Duo, and is without detectable side effects.  相似文献   

5.
We examined nitrate-dependent Fe2+ oxidation mediated by anaerobic ammonium oxidation (anammox) bacteria. Enrichment cultures of “Candidatus Brocadia sinica” anaerobically oxidized Fe2+ and reduced NO3 to nitrogen gas at rates of 3.7 ± 0.2 and 1.3 ± 0.1 (mean ± standard deviation [SD]) nmol mg protein−1 min−1, respectively (37°C and pH 7.3). This nitrate reduction rate is an order of magnitude lower than the anammox activity of “Ca. Brocadia sinica” (10 to 75 nmol NH4+ mg protein−1 min−1). A 15N tracer experiment demonstrated that coupling of nitrate-dependent Fe2+ oxidation and the anammox reaction was responsible for producing nitrogen gas from NO3 by “Ca. Brocadia sinica.” The activities of nitrate-dependent Fe2+ oxidation were dependent on temperature and pH, and the highest activities were seen at temperatures of 30 to 45°C and pHs ranging from 5.9 to 9.8. The mean half-saturation constant for NO3 ± SD of “Ca. Brocadia sinica” was determined to be 51 ± 21 μM. Nitrate-dependent Fe2+ oxidation was further demonstrated by another anammox bacterium, “Candidatus Scalindua sp.,” whose rates of Fe2+ oxidation and NO3 reduction were 4.7 ± 0.59 and 1.45 ± 0.05 nmol mg protein−1 min−1, respectively (20°C and pH 7.3). Co-occurrence of nitrate-dependent Fe2+ oxidation and the anammox reaction decreased the molar ratios of consumed NO2 to consumed NH4+ (ΔNO2/ΔNH4+) and produced NO3 to consumed NH4+ (ΔNO3/ΔNH4+). These reactions are preferable to the application of anammox processes for wastewater treatment.  相似文献   

6.
Patients with various forms of glomerulonephritis, but excluding those with minimal glomerular changes, were admitted to a controlled trial of a regimen which combined azathioprine in a dosage of 2·5 mg/kg/day with prednisone in a dosage of 20 mg/day (adults) or 0·5 mg/kg/day (children). Of 149 patients included, 32 of them under the age of 15, 72 were randomly allocated to the “treatment” group and 77 to the “control” group. There was no evidence of benefit from the treatment group as a whole; and the mortality was in fact higher in the treated group.  相似文献   

7.
Anesthetic management of patients undergoing pulmonary vein isolation for atrial fibrillation has specific requirements. The feasibility of non-invasive ventilation (NIV) added to deep sedation procedure was evaluated.Seventy-two patients who underwent ablation procedure were retrospectively revised, performed with (57%) or without (43%) application of NIV (Respironic® latex-free total face mask connected to Garbin ventilator-Linde Inc.) during deep sedation (Midazolam 0.01–0.02 mg/kg, fentanyl 2.5–5 μg/kg and propofol: bolus dose 1–1.5 mg/kg, maintenance 2–4 mg/kg/h).In the two groups (NIV vs deep sedation), differences were detected in intraprocedural (pH 7.37 ± 0.05 vs 7.32 ± 0.05, p = 0.001; PaO2 117.10 ± 27.25 vs 148.17 ± 45.29, p = 0.004; PaCO2 43.37 ± 6.91 vs 49.33 ± 7.34, p = 0.002) and in percentage variation with respect to basal values (pH −0.52 ± 0.83 vs −1.44 ± 0.87, p = 0.002; PaCO2 7.21 ± 15.55 vs 34.91 ± 25.76, p = 0.001) of arterial blood gas parameters. Two episodes of respiratory complications, treated with application of NIV, were reported in deep sedation procedure. Endotracheal intubation was not necessary in any case. Adverse events related to electrophysiological procedures and recurrence of atrial fibrillation were recorded, respectively, in 36% and 29% of cases.NIV proved to be feasible in this context and maintained better respiratory homeostasis and better arterial blood gas balance when added to deep sedation.  相似文献   

8.
Adenosine is a neuroprotective agent that inhibits neuronal activity and modulates neurotransmission. Previous research has shown adenosine gradually accumulates during pathologies such as stroke and regulates neurotransmission on the minute-to-hour time scale. Our lab developed a method using carbon-fiber microelectrodes to directly measure adenosine changes on a sub-second time scale with fast-scan cyclic voltammetry (FSCV). Recently, adenosine release lasting a couple of seconds has been found in murine spinal cord slices. In this study, we characterized spontaneous, transient adenosine release in vivo, in the caudate-putamen and prefrontal cortex of anesthetized rats. The average concentration of adenosine release was 0.17±0.01 µM in the caudate and 0.19±0.01 µM in the prefrontal cortex, although the range was large, from 0.04 to 3.2 µM. The average duration of spontaneous adenosine release was 2.9±0.1 seconds and 2.8±0.1 seconds in the caudate and prefrontal cortex, respectively. The concentration and number of transients detected do not change over a four hour period, suggesting spontaneous events are not caused by electrode implantation. The frequency of adenosine transients was higher in the prefrontal cortex than the caudate-putamen and was modulated by A1 receptors. The A1 antagonist DPCPX (8-cyclopentyl-1,3-dipropylxanthine, 6 mg/kg i.p.) increased the frequency of spontaneous adenosine release, while the A1 agonist CPA (N6-cyclopentyladenosine, 1 mg/kg i.p.) decreased the frequency. These findings are a paradigm shift for understanding the time course of adenosine signaling, demonstrating that there is a rapid mode of adenosine signaling that could cause transient, local neuromodulation.  相似文献   

9.

Objective

To investigate the differences in breathing pattern and effort in infants at birth who failed or succeeded on continuous positive airway pressure (CPAP) during the first 48 hours after birth.

Methods

Respiratory function recordings of 32 preterm infants were reviewed of which 15 infants with a gestational age of 28.6 (0.7) weeks failed CPAP and 17 infants with a GA of 30.1 (0.4) weeks did not fail CPAP. Frequency, duration and tidal volumes (VT) of expiratory holds (EHs), peak inspiratory flows, CPAP-level and FiO2-levels were analysed.

Results

EH incidence increased <6 minutes after birth and remained stable thereafter. EH peak inspiratory flows and VT were similar between CPAP-fail and CPAP-success infants. At 9-12 minutes, CPAP-fail infants more frequently used smaller VTs, 0-9 ml/kg and required higher peak inspiratory flows. However, CPAP-success infants often used large VTs (>9 ml/kg) with higher peak inspiratory flows than CPAP-fail infants (71.8 ± 15.8 vs. 15.5 ± 5.2 ml/kg.s, p <0.05). CPAP-fail infants required higher FiO2 (0.31 ± 0.03 vs. 0.21 ± 0.01), higher CPAP pressures (6.62 ± 0.3 vs. 5.67 ± 0.26 cmH2O) and more positive pressure-delivered breaths (45 ± 12 vs. 19 ± 9%) (p <0.05)

Conclusion

At 9-12 minutes after birth, CPAP-fail infants more commonly used lower VTs and required higher peak inspiratory flow rates while receiving greater respiratory support. VT was less variable and larger VT was infrequently used reflecting early signs of fatigue.  相似文献   

10.
11.
A longitudinal prospective study of serum cholesterol concentrations during the first year of life has been carried out in 302 healthy babies. The results show that serum cholesterol estimations in cord blood cannot be used as a screening test for the diagnosis of familial hypercholesterolaemia. The only child subsequently found to have the condition had a cord serum cholesterol of 85 mg/100 ml compared with the mean value for the group of 78 mg/100 ml. The babies who had cord values greater than 100 mg/100 ml had values distributed throughout the normal range when re-examined at 1 year of age. Serum cholesterol concentrations during the early months of life were markedly influenced by the type of milk fed; it is suggested that investigations to establish the diagnosis of familial hypercholesterolaemia are deferred until the child is about 1 year old and feeding with cows'' milk and mixed diet is established.Values obtained for serum cholesterol concentrations (mg/100 ml, mean ± 1 S.D.) in healthy infants in this study were: at birth 78 ± 23, at 1 week 155 ± 31, at 6 weeks 155 ± 31, at 4 months 184 ± 36, at 8 months 195 ± 37, and at 1 year 191 ± 36.  相似文献   

12.

Objective

To determine levels of athero-protective IgM antibodies against phosphorylcholine in mothers and term-born normal or low birth weight infants.

Approach

Twenty three mother-infant pairs were studied, of whom 16 infants were within the normal weight range for gestational age (NGA; 3652[504] g) and 7 were small for gestational age (SGA; birth weight: 2715[255] g), the latter <2SD below the Swedish reference data mean for normal fetal growth. All infants were born at term (mean±SD 40.5±1.1 weeks). Serum was available from 6 mothers with SGA and 14 with NGA infants. Participating mothers were aged 34.0±3.9 years (no difference between groups). Fourteen neonates were boys and seven were girls. Levels of anti-PC IgM were determined by ELISA.

Results

Neonatal IgM anti-PC levels were low (undetectable in 8 infants out of which 3 were SGA) with a median of 76[range 0–2.51] U/ml. Maternal IgM anti-PC levels were significantly higher (median 7198[range: 25.32–656.0]) U/ml) and the proportion of mothers in highest quartile (>75th percentile) was larger in mothers of NGA-infants (43%) vs. those of SGA-infants (0%, p = 0.032).

Conclusions

IgM anti-PC levels are low at birth, which suggests that these antibodies do not play a “housekeeping” role in immune function during fetal life/development, but arise predominately on exposure to external antigens after birth. Furthermore, low maternal IgM anti-PC levels may play a role in placental insufficiency, contributing to poor fetal growth and a small-for-date baby. This preliminary observation may have implications for the future risk of atherosclerosis/cardiovascular disease development in pregnant women and their offspring.  相似文献   

13.

Background

The β2 adrenergic receptor (β2AR) plays an important role in ischemia-reperfusion (I/R) injury in various organs. Recently, a selective β2AR agonist clenbuterol was suggested to protect against cerebral I/R injury. This study was designed to investigate changes of β2ARs after spinal cord I/R injury and dose-effects of aorta-infused clenbuterol on spinal cord I/R injury in rabbits.

Methods

Spinal cord ischemia was induced in New Zealand white rabbits by infrarenal abdominal aortic occlusion with a balloon catheter for 30 minutes except the sham group. During occlusion, nothing (I/R group), normal saline (NS group) or clenbuterol at different doses of 0.005, 0.01, 0.05, 0.1, 0.5, or 1 mg/kg (C0.005, C0.01, C0.05, C0.1, C0.5, and C1 groups) was infused into the occluded aortic segments. The hemodynamic data, blood glucose and serum electrolytes were measured during experimental period. Neurological function was assessed according to the modified Tarlov scales until 48 hours after reperfusion. After that, the lumbar spinal cord was harvested for β2AR immunohistochemistry and histopathologic evaluation in the anterior horns.

Results

The β2AR expression in the anterior horns of the spinal cord was significantly higher in the I/R group than in the sham group. Tarlov scores and the number of viable α-motor neurons were higher in C0.01-C0.5 groups than in the NS group, C0.005 and C1 groups and were highest in the C0.1 group. Hypotension and hyperglycemia were found in the C1 group.

Conclusion

β2ARs in the anterior horn were upregulated after spinal cord I/R injury. Aortic-infused clenbuterol (0.01–0.5 mg/kg) can attenuate spinal cord I/R injury dose-dependently during the ischemic period. The Optimal dosage was 0.1 mg/kg. Activation of β2AR could be a new therapeutic strategy for the treatment of spinal cord I/R injury.  相似文献   

14.
Intravenous lignocaine (1 mg./kg. body weight) was found to produce insignificant haemodynamic changes, and in particular no reduction in myocardial contractility. A rate of 2 mg./minute infused intravenously is suggested for therapeutic purposes.In anaesthetized dogs an infusion of 13·5 mg./minute caused moderate haemodynamic depression and a maximum plasma level of 7 μg./ml. Massive injections of 200 and 400 mg. of lignocaine produced a maximum plasma level of 13·8 and 27·8 μg./ml., respectively, and in the latter failure of myocardial contraction in the presence of a normal E.C.G. ensued (“pump failure”). Lignocaine appears to alter the uptake of calcium by myocardial sarcoplasmic reticulum, and this may explain the negative inotropic effect of large doses.  相似文献   

15.

Background

Prevention of postnatal growth restriction of very preterm infants still represents a challenge for neonatologists. As standard feeding regimens have proven to be inadequate. Improved feeding strategies are needed to promote growth. Aim of the present study was to evaluate whether a set of nutritional strategies could limit the postnatal growth restriction of a cohort of preterm infants.

Methodology/Principal Findings

We performed a prospective non randomized interventional cohort study. Growth and body composition were assessed in 102 very low birth weight infants after the introduction of a set of nutritional practice changes. 69 very low birth weight infants who had received nutrition according to the standard nutritional feeding strategy served as a historical control group. Weight was assessed daily, length and head circumference weekly. Body composition at term corrected age was assessed using an air displacement plethysmography system. The cumulative parenteral energy and protein intakes during the first 7 days of life were higher in the intervention group than in the historical group (530±81 vs 300±93 kcal/kg, p<0.001 and 21±2.9 vs 15±3.2 g/kg, p<0.01). During weaning from parenteral nutrition, the intervention group received higher parental/enteral energy and protein intakes than the historical control group (1380±58 vs 1090±70 kcal/kg; 52.6±7 vs 42.3±10 g/kg, p<0.01). Enteral energy (kcal/kg/d) and protein (g/kg/d) intakes in the intervention group were higher than in the historical group (130±11 vs 100±13; 3.5±0.5 vs 2.2±0.6, p<0.01). The negative changes in z score from birth to discharge for weight and head circumference were significantly lower in the intervention group as compared to the historical group. No difference in fat mass percentage between the intervention and the historical groups was found.

Conclusions

The optimization and the individualization of nutritional intervention promote postnatal growth of preterm infants without any effect on percentage of fat mass.  相似文献   

16.
17.
Prostaglandins E2 and F2α were administered by mouth to induce labour in 24 patients at or past term. The drugs were administered at two-hourly intervals in doses ranging from 0·5 to 1·5 mg for prostaglandin E2 and from 5 to 15 mg for prostaglandin F2α. Of the 10 cases in which prostaglandin E2 was used, labour was successfully induced in eight and there were no side effects. With prostaglandin F2α labour was induced in 12 of 14 patients nine of whom had gastrointestinal disturbance, mostly of mild degree. With both drugs the infant was apparently unaffected and Apgar scores were satisfactory. Uterine hypertonus was not observed and the postpartum blood loss was within normal limits.  相似文献   

18.
Study of 182 newborn babies has shown that among bottle-fed infants the mean plasma bilirubin concentration was slightly but significantly higher (P <0·01) in those whose mothers had previously used steroid contraceptives. A similar finding was not noted among breast-fed infants.A further 16 infants whose mothers had received progestogen therapy during their pregnancy had a mean plasma bilirubin concentration which was significantly higher than each of the four other groups of infants studied (P <0·01). Icterus occasionally reached clinically important levels in these babies.  相似文献   

19.
We investigated the changes in both performance and selected physiological parameters following a Live High-Train Low (LHTL) altitude camp in either normobaric hypoxia (NH) or hypobaric hypoxia (HH) replicating current “real” practices of endurance athletes. Well-trained triathletes were split into two groups (NH, n = 14 and HH, n = 13) and completed an 18-d LHTL camp during which they trained at 1100–1200 m and resided at an altitude of 2250 m (PiO2  = 121.7±1.2 vs. 121.4±0.9 mmHg) under either NH (hypoxic chamber; FiO2 15.8±0.8%) or HH (real altitude; barometric pressure 580±23 mmHg) conditions. Oxygen saturations (SpO2) were recorded continuously daily overnight. PiO2 and training loads were matched daily. Before (Pre-) and 1 day after (Post-) LHTL, blood samples, VO2max, and total haemoglobin mass (Hbmass) were measured. A 3-km running test was performed near sea level twice before, and 1, 7, and 21 days following LHTL. During LHTL, hypoxic exposure was lower for the NH group than for the HH group (220 vs. 300 h; P<0.001). Night SpO2 was higher (92.1±0.3 vs. 90.9±0.3%, P<0.001), and breathing frequency was lower in the NH group compared with the HH group (13.9±2.1 vs. 15.5±1.5 breath.min−1, P<0.05). Immediately following LHTL, similar increases in VO2max (6.1±6.8 vs. 5.2±4.8%) and Hbmass (2.6±1.9 vs. 3.4±2.1%) were observed in NH and HH groups, respectively, while 3-km performance was not improved. However, 21 days following the LHTL intervention, 3-km run time was significantly faster in the HH (3.3±3.6%; P<0.05) versus the NH (1.2±2.9%; ns) group. In conclusion, the greater degree of race performance enhancement by day 21 after an 18-d LHTL camp in the HH group was likely induced by a larger hypoxic dose. However, one cannot rule out other factors including differences in sleeping desaturations and breathing patterns, thus suggesting higher hypoxic stimuli in the HH group.  相似文献   

20.
In a population based cohort study information on the consumption of alcohol was obtained from 95% of the 952 consecutive primigravidas who lived in the Dundee district and attended for antenatal care between May 1985 and April 1986. Before realising that they were pregnant more than 90% drank alcohol and 53% were cigarette smokers. During the first four months of pregnancy, however, the proportion of women drinking and smoking fell to 56% and 44%, respectively. Alcohol consumption of more than 120 g absolute alcohol/week (12 or more standard drinks) during pregnancy was related to shorter gestational age (-2·6 weeks), smaller head circumference (-18 mm), shorter (-21 mm) and lighter (-499 g) babies, and lower Apgar scores at five minutes (-0·4, all p<0·01). After adjustment for the effect of smoking, social class, mother''s size, and other confounding factors, however, an alcohol intake of more than 120 g/week was significantly related only to shorter gestational age (-2·0 weeks, p<0·001) and lower Apgar score at five minutes (-0·2, p<0·05). Alcohol intake in the region of 100-119 g/week was significantly related to smaller head circumference (-12 mm, p<0·05). Analysis by type of beverage consumed suggested that beer rather than wine or spirits was associated with a poorer outcome.As there was no detectable effect on pregnancy of alcohol consumption below 100 g/week, it is suggested that health education should be directed towards mothers who drink more than this amount.  相似文献   

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