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Experimentally modified breathing pattern in human subjects, by varying the inspired gas mixture or administering different neuromodulators, has been studied extensively in the past, yet unmodified breathing has not. Moreover, most data refer to infants during sleep and adults during wakefulness. We studied the baseline breathing pattern of preterm infants [n = 10; GA 30 (27-34) wk (median, range)]; term infants [n = 10; GA 40 (39-41) wk)], and adult subjects [n = 10; age 31 (17-48) y)] during quiet sleep. A flow-through system was used to measure ventilation. We found: (i) instantaneous ventilation was 0.273 ± 0.006, 0.200 ± 0.003, and 0.135 ± 0.002 L · min[sup -1] · kg[sup -1] in preterm, term infants, and adult subjects; the coefficients of variation were 39%, 25%, and 14% (p < 0.01). The greater coefficient of variation in neonates compared to adults related to increased variability in Vt (39% and 25% in preterm and term infants vs 14% in adults; p < 0.01) and f (39% and 22% vs 9%; p < 0.01). The major determinant of frequency in preterm infants was Te (81% variability), Ti varying less (25% variability); (ii) V[sub T]/Ti decreased and Ti/Ttot increased with age; (iii) the higher breath-to-breath variability in preterm infants was associated with larger changes in alveolar PCO[sub 2] and a larger variability in O[sub 2] saturation than later in life. We conclude: (i) the high breath-to-breath variability in frequency in preterm infants closely relates to variation in Te; (ii) decreased effective inspiratory timing (Ti/Ttot) in preterm infants compared with adults likely reflects their high pulmonary impedance; and (iii) greater breath-to-breath variability in ventilation in neonates with large variations in alveolar PCO[sub 2] and O[sub 2] saturation remains when compared with values in the sleeping adult. We speculate that high variability in Te early in life represents an effort to maintain lung volume through increased post-inspiratory diaphragmatic activity and increased upper airway resistance in an attempt to avoid collapse due to poor chest wall recoil. [ABSTRACT FROM AUTHOR]

Sixty-five infertile women, 37 with anovulation, eight with ovulatory disturbances and 20 with unexplained infertility were treated by a combination of clomiphene citrate (CC) from cycle day S (or 3) and human menopausal gonado trophin (HMG) begun 3 days later for induction or enhancemeat of ovulation. Monitoring was carried out by measuring preovulatory 17-β-oestradiol (E) and progesterone (P) concentrations in blood samples and by follicle measurements using ultrasound. Forty-seven pregnancies resulted with a multiple pregnancy rate of 7.7% for those completed. This incidence is very low and within the range found for CC induction and might result from the later commencement of stimulation compared with many other protocols. These results were achieved with a low incidence of ovarian hyperstimulation syndrome (2.6% per cycle). The HMG doses given were low in comparison with those found in other forms of induction. The deleterious effects of this combined mode of induction on cervical mucus and the occurrence of premature spontaneous ovulation were much less than in the sequential mode of treatment. These results suggest that combined induction treatment by CC and HMG as described offers a means of achieving low rates of multiple pregnancies a known complication in the induction of ovulation. [ABSTRACT FROM PUBLISHER]

The movement of the chest during breathing has been recorded in normal and asthmatic subjects by means of electronic transducers which measured changes in anteroposterior and lateral diameters. Preliminary studies showed that exercise-induced bronchoconstriction caused distortion of the movement of the diameters in relation to each other and to volume change recorded at the mouth. Because of the thoracic gas compression which occurs during breathing, volume change at the mouth does not represent the change in chest volume and further studies were therefore undertaken in a whole-body plethysmograph. These studies showed that the addition of a resistance to the airway of a normal subject distorted the movement of one diameter (usually the anteroposterior) in relation to the other and to volume. With exercise-induced asthma, the movement of both diameters was affected with the anteroposterior lagging behind the volume change. There was an approximate linear relationship between the degree of distortion and airways resistance in the asthmatic subjects and in one normal subject. The physical sign of costal margin paradox could be related to the severity of the obstruction. [ABSTRACT FROM PUBLISHER]

Evidence is accumulating for the transgenerational effects of maternal stress on offspring. A particular increasing concern is the possible transgenerational effects of community exposure to war and terror. Here, 107 mothers that had been exposed to war, were assessed with their 3 year old children (52 % girls) who had been conceived after the end of the war, and thus never directly exposed to war. The circumscribed nature (missile bombardment) and temporal limits (34 days) of the tragic 2006 Lebanon war in the north of Israel, affords a unique methodological opportunity to isolate an epoch of stress from preceding and subsequent normal life. We find that war experience engenders higher levels of mothers' separation anxiety, lower emotional availability in mother-child interaction, and lower levels of children's adaptive behavior. The novelty of these findings lies in documenting the nature and strength of transgenerational effects of war-related stress on offspring that were never exposed. In addition, because these effects were obtained after 4 years of a continuing period of normality, in which the children were born and raised, it suggests that an extended period of normality does not obliterate the effects of the war on mother and child behavior as assessed herein. Despite the study limitations, the results are indicative of persisting transgenerational effects of stress.

Objective: To evaluate the association between stage III or higher retinopathy of prematurity (ROP) and other prematurity disorders and parameters., Design: Retrospective, case-control study., Participants: The subjects of the study were 55 consecutive premature neonates with stage III or higher ROP and 110 consecutive premature neonates without ROP., Methods: We compared consecutive premature neonates regarding the presence of ROP and other disorders as well as demographic and laboratory parameters., Results: Gestational age (p < 0.001); birth weight (p < 0.001); male sex (p = 0.031); bilirubin levels (p < 0.001); breast feeding (p < 0.001); clinical and laboratory sepsis (p < 0.001); number of sepsis events (p < 0.001); ventilation need (p < 0.001); number of ventilation days (p < 0.001); theophylline and surfactant use (p < 0.001); blood transfusions (p < 0.001); number of blood transfusions (p < 0.001); intraventricular hemorrhage and bronchopulmonary dysplasia (p = 0.001); and other factors differed in the two groups. The logistic regression model showed a correlation between low gestational age (OD 0.474, CI 0.359-0.626); male sex (OD 2.991, CI 1.077-8.305); blood transfusion (OD 14.159, CI 1.570-127.7); and sepsis (OD 12.376, CI 2.532-60.503)., Conclusions: Certain disorders and parameters, such as sepsis and blood transfusions, may be predict the appearance of stage III or higher ROP. Close monitoring of neonates with these findings is imperative. Early detection and treatment of sepsis and reduction of blood transfusions may decrease the incidence of ROP that requires treatment., (Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the efficacy of povidone iodine solution 2.5% and tetracycline ointment 1% in prevention of ophthalmia neonatorum (ON)., Design: Prospective, randomized, controlled observational study., Participants: Three-hundred ninety-four full-term neonates., Methods: A randomized comparison between 201 neonates randomly treated with povidone iodine 2.5% solution and 193 treated with tetracycline 1% ointment., Main Outcomes Measures: Incidence of ON., Results: The incidence of ON was significantly higher after povidone iodine than tetracycline prophylaxis (15.4% and 5.2% respectively; P = 0.001). Noninfective ON developed in 10 (5%) of the 201 neonates treated with povidone iodine and in none (0%) of the neonates treated with tetracycline (P = .002). Infective ON was detected in 21 (10.4%) of the neonates treated with povidone iodine and in 10 (5.2%) after treatment with tetracycline (P = .052). Ophthalmia neonatorum appeared more commonly in the first 3 days after treatment with povidone iodine (P = .043). The spectrum of the infective isolates was similar in the 2 groups., Conclusions: Povidone iodine was associated with noninfective (sterile) conjunctivitis, probably because of its toxicity to the ocular surface in neonates. Tetracycline was marginally more effective against infective ON. For these reasons, tetracycline, rather than povidone iodine, is recommended for prevention of ON., (Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Background: The perinatal-neonatal course of very-low-birth-weight (VLBW) infants might affect their childhood growth. We evaluated the effect of parental anthropometry and perinatal and neonatal morbidity of VLBW neonates on their childhood growth., Methods: We obtained parental anthropometry, height and weight at age 6-10.5 years of 334 children born as VLBW infants. Parental, perinatal and neonatal data of these children were tested for association with childhood anthropometry., Results: (1) Maternal and paternal weight standard deviation score (SDS) and discharge weight (DW) SDS were associated with childhood weight SDS (R(2)= 0.111, p < 0.00001); (2) Maternal and paternal height SDS, corrected gestational age (GA) at discharge, maternal assisted reproduction and SGA status were associated with childhood height SDS (R(2)= 0.208, p < 0.00001); (3) paternal weight SDS, DW SDS and surfactant therapy were associated with childhood body mass index (BMI) SDS (R(2)= 0.096, p < 0.00001). 31.1% of VLBW infants had DW SDS < -1.88, and are to be considered small for gestational age ('SGA'). One quarter of these infants did not catch up by age 6-10.5 years., Conclusion: Childhood anthropometry of VLBW infants depends on parental anthropometry, postnatal respiratory morbidity and growth parameters at birth and at discharge. Almost one-third of VLBW premature infants had growth restriction at discharge from neonatal intensive care unit (NICU), a quarter of whom did not catch up by age 6-10.5 years.

The rare autosomal recessive disorder pyridoxine 5'-phosphate oxidase (PNPO) deficiency is a recently described cause of neonatal and infantile seizures. Clinical evaluation, and biochemical and genetic testing, were performed on a neonate with intractable seizures who did not respond to anticonvulsant drugs and pyridoxine. Sequencing of the PNPO gene revealed a novel homozygous c.284G>A transition in exon 3, resulting in arginine to histidine substitution and reduced activity of the PNPO mutant to 18% relative to the wild type. This finding enabled molecular prenatal diagnosis in a subsequent pregnancy, accurate genetic counseling in the large inbred family, and population screening.

Cryogenic temperature transmission electron microscopy (cryo-TEM) makes it possible to study the nanostructure of a wide range of fluid phases with a high degree of preservation. Most studies based on scanning electron microscopy or TEM employ specimen preparation techniques that give extraordinary results for tissues, but alter the native structure of complex fluid substances such as lung surfactant. In this paper, we evaluated direct-imaging cryo-TEM as a method to study the morphology of the aqueous form of lung surfactant. We compared the morphology of samples obtained from different species, and cryo-TEM data to data obtained by staining-and-drying. We demonstrate that cryo-TEM preserves and images much better sample morphology and fine details of the surfactant structures. We show that cryo-TEM, a method based on physical fixation, which avoids chemical changes and aggregate rearrangement, is a most useful tool to further our understanding of lung surfactant and its function.

Forty-one children aged 10.5 +/- 0.2 years (range, 8.0-15.0 yr), born with low birth weight of 1,218.2 +/- 36.6 g (range, 765-1,580 g) were selected from hospital archives on the basis of whether they had received neonatal diuretic treatment or as healthy matched controls. The children were tested for salt appetite and sweet preference, including rating of preferred concentration of salt in tomato soup (and sugar in tea), ratings of oral spray (NaCl and sucrose solutions), intake of salt or sweet snack items, and a food-seasoning, liking, and dietary questionnaire. Results showed that sodium appetite was not related to neonatal diuretic treatment, birth weight, or gestational age. However, there was a robust inverse correlation (r = -0.445, P < 0.005) between reported dietary sodium intake and the neonatal lowest serum sodium level (NLS) recorded for each child as an index of sodium loss. The relationship of NLS and dietary sodium intake was found in both boys and girls and in both Arab and Jewish children, despite marked ethnic differences in dietary sources of sodium. Hence, low NLS predicts increased intake of dietary sodium in low birth weight children some 8-15 yr later. Taken together with other recent evidence, it is now clear that perinatal sodium loss, from a variety of causes, is a consistent and significant contributor to long-term sodium intake.

Diagnosis and treatment of an anuric premature infant with severe respiratory compromise and a normal renal ultrasound (US), is a difficult task that requires a multidisciplinary approach. A 29-week gestation premature male infant, born after 5 weeks of worsening oligohydramnios, was ventilated for respiratory distress and remained anuric. Intensive clinical investigations and pediatric nephrology consultation that predicted very poor prognosis were followed by progressive renal failure, electrolyte imbalance, respiratory failure, ventricular arrhythmia, and finally cardiac arrest and death on day 5. In view of the predicted poor outcome, and after discussion with the parents, a decision was made not to start peritoneal dialysis (PD), and to offer only palliative therapy, with comfort care alone. Pre and postnatal diagnosis lead, in this case, to an ethical challenge that focuses on the question of futility., (Copyright 2006 John Wiley & Sons, Ltd.)

Nine premature infants developed early onset sepsis and/or pneumonia with Haemophilus influenzae during a period of 53 months (January 2000 -May 2004). Their respiratory problems were pneumonia-like rather than classic respiratory distress syndrome. In 8 of the cases, the pathogen was a beta-lactamase-negative, nontypable H. influenzae. In the remaining case, the Haemophilus identified was type d. Before January 2000, no case of beta-lactamase-negative, nontypable H. influenzae sepsis or pneumonia had been recorded.

Splanchnic ischemia-reperfusion (I/R) causes tissue hypoxia that triggers local and systemic microcirculatory inflammatory responses. We evaluated the effects of hyperoxia in I/R induced by 40-min superior mesenteric artery (SMA) occlusion and 120-min reperfusion in four groups of rats: 1) control (anesthesia only), 2) sham operated (all surgical procedures without vascular occlusion; air ventilation), 3) SMA I/R and air, 4) SMA I/R and 100% oxygen ventilation started 10 min before reperfusion. Leukocyte rolling and adhesion in mesenteric microvessels, pulmonary microvascular blood flow velocity (BFV), and macromolecular (FITC-albumin) flux into lungs were monitored by intravital videomicroscopy. We also determined pulmonary leukocyte infiltration. SMA I/R caused marked decreases in mean arterial blood pressure (MABP) and blood flow to the splanchnic and hindquarters vascular beds and pulmonary BFV and shear rates, followed by extensive increase in leukocyte rolling and adhesion and plugging of >50% of the mesenteric microvasculature. SMA I/R also caused marked increase in pulmonary sequestration of leukocytes and macromolecular leak with concomitant decrease in circulating leukocytes. Inhalation of 100% oxygen maintained MABP at significantly higher values (P < 0.001) but did not change regional blood flows. Oxygen therapy attenuated the increase in mesenteric leukocyte rolling and adherence (P < 0.0001) and maintained microvascular patency at values not significantly different from sham-operated animals. Hyperoxia also attenuated the decrease in pulmonary capillary BFV and shear rates, reduced leukocyte infiltration in the lungs (P < 0.001), and prevented the increase in pulmonary macromolecular leak (P < 0.001), maintaining it at values not different from sham-operated animals. The data suggest that beneficial effects of normobaric hyperoxia in splanchnic I/R are mediated by attenuation of both local and remote inflammatory microvascular responses.

To test the hypothesis that the crescendo-decrescendo type of pattern of periodic breathing is more common in infants than in adulthood, we examined the morphologies of periodic breathing in four groups of subjects: group 1 (n=10, gestational age 30+/-1 week), group 2 (n=10, GA 31+/-1 week), group 3 (n=10, GA 38+/-1 week), and group 4 (n=10, age 50+/-4 years). Respiratory pattern and ventilation were measured using a flow-through system. The breathing morphologies were defined according to the respiratory flow. We found (1) a predominant crescendo-decrescendo pattern in preterm infants (groups 1 and 2, >50%) and this changed to a predominant decrescendo breathing in adults (group 4, 50%); (2) total breathing cycle and its phases did not change significantly among the neonatal groups, but they almost doubled in adult subjects; however, the number of breaths per breathing interval remained the same (crescendo-decrescendo) or less (flat and decrescendo) in adults as compared to preterm infants; (3) the duty cycle (breathing interval/cycle duration) remained consistent with age; and (4) at the beginning of each breathing interval, alveolar P(CO2) was highest and alveolar P(O2) and O2 saturation lowest. The findings suggest a change in the strategy of the respiratory control system during periodic breathing between the infant and the adult, perhaps dictated by mechanical and chemoreceptor limitations early in age, with a switch from a crescendo-decrescendo to a predominantly decrescendo pattern.

Over the last two decades, drug and alcohol abuse by pregnant women has spread to epidemic proportions. Maternal drug abuse has neurobehavioral and somatic effects which may be long-lasting and devastating to the offspring. Opiates, such as heroin and pain killers that contain a narcotic component, are widely abused today. A prominent manifestation of fetal exposure to these drugs is the neonatal withdrawal syndrome, which typically includes wakefulness, jitteriness and other symptoms of cerebral irritability. These, in turn, may interrupt early mother-infant interaction, affecting the infant's long-term emotional and cognitive development. Fetal cocaine exposure may cause neonatal cerebral irritability, changes in habituation responses, reduced head circumference, poor mental development and long-lasting impairment of the brain. Benzodiazepines can cause fetal dysmorphism (including microcephaly), neurological and behavioral impairments and neonatal withdrawal symptoms. Maternal use of amphetamines may cause neonatal dysphoria and agitation, as well as long-term lassitude and drowsiness that may result in poor feeding. Fetal exposure to alcohol may cause neonatal withdrawal symptoms, maladaptive behavior in childhood and the fetal alcohol syndrome (including microcephaly). Maternal alcohol consumption is also a common cause of mental retardation. Fetal exposure to marijuana may delay maturation of the visual system and impair memory and verbal performance at 2 years of age. The inevitable conclusion is that society must seek ways not only to treat, but also to prevent this epidemic. To this end, a key factor would be to identify potential drug abusing mothers before they reach the stage of prenatal care and educate them regarding the fatal consequences of drug abuse.

Human neonates are occasionally treated with diuretics, and we investigated whether this causes a long-term enhancement of salt preference. Salt preference was examined in children aged 4-11 years. Twenty one of the children had received furosemide therapy as preterm neonates, and 24 were preterm neonates from the same ward that had no furosemide therapy. No differences were found between the two groups in preferred concentration of NaCl in soup, in consumption of salty items, and in blood and urine sodium and creatinine. However, in a tested subsample, fractional excretion of sodium (FENa) was higher in the neonatally treated children, suggesting increased salt intake. Reported severity of morning sickness in the mother when pregnant with the child, the child's history of diarrhoea and vomiting and degree of dietary salt exposure were obtained by questionnaire. These variables also did not influence salt preference, or blood and urine sodium and creatinine, except for a correlation between dietary salt exposure and blood sodium concentration. We conclude that while the physiological evidence suggests increased salt intake in children treated neonatally with furosemide, more sensitive tests of salt preference at this age are required to reveal any influence early mineralofluid loss may have on salt preference in childhood., (Copyright 1998 Academic Press Limited.)

We tested the hypothesis that the surge of norepinephrine at birth is associated with the establishment of continuous breathing. Therefore, we studied whether the administration of norepinephrine could enhance fetal breathing during administration of oxygen, or 100% O2 plus cord occlusion, and if phenoxybenzamine would reverse these changes. Fetal sheep were instrumented in late gestation to measure electrocortical activity and diaphragmatic electromyography. These parameters and blood gases were measured before and during in utero administration of nitrogen, 100% O2, 100% O2 plus umbilical cord occlusion, and subsequently during umbilical reperfusion and recovery. Nine fetuses (14 experiments) received continuous norepinephrine (0.13 microgram/kg/min) throughout the experiment while 9 other fetuses (18 experiments) underwent the same treatment without the hormonal infusion. We found that norepinephrine inhibited the breathing induced by 100% O2 plus cord occlusion, despite a significant increase in the duration of low-voltage electrocortical activity; phenoxybenzamine reverted these changes. The findings suggest that the surge of norepinephrine at birth is probably not the primary mechanism for establishment of continuous breathing.

To test the hypothesis that there is an association among short apneas (3-10 s), body movements, and sighs, we studied 11 preterm infants (body weight 1,500 +/- 200 g, mean +/- SE; gestational age 30 +/- 1 weeks, postnatal age 28 +/- 5 days) using a flow-through system. A total of 1,166 apneas, 1,024 movements, and 473 sighs were recorded. Of the 1,166 apneas, 460 (39%) were associated with movements, 91 (8%) with sighs, and 226 (19%) with both movements and sighs. The rate of apneas associated with movements and sighs was significantly greater than expected if only a random association had occurred. These differences remained in quiet, rapid eye movement, and indeterminate sleep. The frequency of each of the three events was similar in a given sleep state. Of the 460 movements associated with apnea, 26% preceded, 23% followed, and 51% occurred during apnea. Similarly, of the 315 sighs associated with apnea, 44% preceded and 56% followed apnea. Apneas preceded by movements were longer than those without movements (5.6 +/- 0.2 vs. 4.9 +/- 0.1 s; p = 0.01). Oxygen saturation before apnea with movement (94 +/- 0.1%) was lower than before apnea alone (96 +/- 0.6%; p = 0.02) and also lower than before movement alone (96 +/- 0.1%; p = 0.001). These findings suggest: (1) there is a strong association among short apneas, movements, and sighs in these infants; (2) sighs appear not to be an isolated event and are likely to be part of a more general motor discharge, and (3) these events are accompanied by mild desaturations and bradycardias.(ABSTRACT TRUNCATED AT 250 WORDS)

We have shown previously that continuous fetal breathing can be induced by 100% O2 alone or combined with umbilical cord occlusion (Baier, Hasan, Cates, Hooper, Nowaczyk & Rigatto, 1990). To know whether it could also be induced by lower O2 concentrations plus cord occlusion, we studied 9 chronically instrumented fetal sheep (16 experiments) using our window model. After a baseline cycle [1 low voltage + 1 high voltage electrocortical activity (ECoG) epoch] the fetal lung was distended via an endotracheal tube to about 30 cm H2O. Inspired N2 (control) and 21 or 30% O2 were given for one cycle each. While on 21% or 30% O2 the umbilical cord was occluded (balloon cuff). In 10 out of 16 experiments breathing output (% maximum of integral of EMGdi x f) increased after cord occlusion from 80 +/- 48 (N2) to 2871 +/- 641 (SEM; P < 0.01); in 7 of them breathing became continuous. Arterial PO2 increased from 14 +/- 1 (N2) to 33.5 +/- 5 Torr (occlusion; P < 0.01). In the other 6 experiments breathing output decreased from 319 +/- 116 (N2) to 86 +/- 38 (occlusion; P < 0.01) and arterial PO2 changed from 18 +/- 1 (N2) to 22 +/- 5 Torr (occlusion; P = 0.4). Arterial PCO2 increased similarly after occlusion in both groups, those which did respond with increased breathing (to 46 +/- 2 Torr) and those which did not respond (to 48 +/- 3 Torr; P = 0.6). The percent low voltage ECoG and the behavioral score increased after occlusion in the responder group only.(ABSTRACT TRUNCATED AT 250 WORDS)

Traditionally, the increase in ventilation occurring after approximately 4 s of CO2 inhalation in preterm infants has been attributed to an action at the peripheral chemoreceptors. However, on a few occasions, we have observed a short apnea (2-3 s) in response to 3-5% CO2 in these infants. To test the hypothesis that this apnea reflects a respiratory sensory reflex to CO2, we gave nine preterm infants [birth wt 1.5 +/- 0.1 (SE) kg, gestational age 31 +/- 1 wk] 7-8% CO2 while they breathed 21% O2. To study the dose-response relationship, we also gave 2, 4, 6, and 8% CO2 to another group of seven preterm infants (birth wt 1.5 +/- 0.1 kg, gestational age 31 +/- 1 wk). In the first group of infants, minute ventilation during 21% O2 breathing (0.232 +/- 0.022 l.min-1.kg-1) decreased after CO2 administration (0.140 +/- 0.022, P < 0.01) and increased with CO2 removal (0.380 +/- 0.054, P < 0.05). This decrease in ventilation was related to an apnea (12 +/- 2.6 s) occurring 7.7 +/- 0.8 s after the beginning of CO2 inhalation. There was no significant change in tidal volume. In the second group of infants, minute ventilation increased during administration of 2, 4, and 6% CO2 but decreased during 8% CO2 because of the presence of an apnea. These findings suggest that inhalation of a high concentration of CO2 (> 6%) inhibits breathing through a respiratory sensory reflex, as described in adult cats (H. A. Boushey and P. S. Richardson. J. Physiol. Lond. 228: 181-191, 1973).(ABSTRACT TRUNCATED AT 250 WORDS)

To measure the response time of the peripheral chemoreceptors, we studied 13 preterm infants [birth weight 1602 +/- 230 g (mean +/- SEM); gestational age 31 +/- 1 wk; postnatal age 15 +/- 1 d] during inhalation of 21% O2 (15 +/- 5 s) followed by 100% O2 (1 min). We used a flow-through system to measure ventilation and gas analyzers to measure alveolar gases. Hypoventilation was observed at 3.6 +/- 0.6 s and was maximal at 6.8 +/- 1 s after O2 began. This maximal response was always associated with an apnea (greater than 3 s). Alveolar PO2 increased from 13.5 +/- 0.1 kPa (101 +/- 0.8 torr) (control) to 28.0 +/- 1.2 kPa (210 +/- 9 torr) (1st O2 breath), to 42.0 +/- 2.4 kPa (315 +/- 18 torr) (1st hypoventilation), to 45.9 +/- 4.1 kPa (344 +/- 31 torr) (breath preceding maximal response), and to 53.6 +/- 4.1 kPa (402 +/- 31 torr) (at maximal response). Minute ventilation was 0.192 +/- 0.011 (control), 0.188 +/- 0.011 (1st O2 breath), 0.088 +/- 0.016 (1st hypoventilation; p less than 0.0001), 0.122 +/- 0.016 (breath preceding maximal response; p less than 0.0002), and 0.044 +/- 0.011 L/min/kg at maximal response (p less than 0.0001). This decrease in ventilation was due to a decrease in frequency with no appreciable change in tidal volume. The initial period of hypoventilation (19 +/- 4 s) was followed by a breathing interval (10 +/- 2 s) and a second period of hypoventilation (14 +/- 3 s) before continuous breathing resumed.(ABSTRACT TRUNCATED AT 250 WORDS)

To discover whether increases in inhaled O2 fraction (FIO2; up to 40%) decrease apnea via an increase in minute ventilation (VE) or a change in respiratory pattern, 15 preterm infants (birth weight 1,300 +/- 354 g, gestational age 29 +/- 2 wk, postnatal age 20 +/- 9 days) breathed 21, 25, 30, 35, and 40% O2 for 10 min in quiet sleep. A nosepiece and a flow-through system were used to measure ventilation. Alveolar PCO2, transcutaneous PO2, and sleep states were also assessed. All infants had periodic breathing with apneas greater than or equal to 3 s. With an increase in FIO2 breathing became more regular and apneas decreased (P less than 0.001). This regularization in breathing was not associated with significant changes in VE. However, the variability of VE, tidal volume, and expiratory and inspiratory times decreased significantly. The results indicate that the more regular breathing observed with small increases in FIO2 was not associated with significant changes in ventilation. The findings suggest that the increased oxygenation decreases apnea and periodicity in preterm infants, not via an increase in ventilation, but through a decrease in breath-to-breath variability of VE.

An infant, born to a mother on carbamazepine monotherapy, had a complex cardiac anomaly, consisting of double-outlet right ventricle (DORV), right-sided aorta, pulmonary artery hypoplasia, left ventricular endocardial fibroelastosis, and anatomic evidence of a spontaneously closed muscular ventricular septal defect (VSD). The last finding is one which, to the best of our knowledge, has never been illustrated before.

Unilateral massive pulmonary atelectasis, and pulmonary interstitial emphysema (PIE) are problems that frequently occur in ventilated premature infants. Selective main bronchus intubation (SBI) of the atelectatic lung, or the contralateral lung in unilateral PIE, is an accepted procedure. However, whereas right SBI is usually easily performed, left SBI is frequently difficult. We have developed a method for left SBI using a regular portex endotracheal tube in which an elliptical hole 1 cm in length has been cut through half the circumference 0.5 cm above the tip of the oblique distal end. With the elliptical side hole directed to the left lung, left SBI can easily, and repeatedly be accomplished. This method may prove life saving in certain cases of unilateral atelectasis or PIE.

Adenosine 3',5'-monophosphate (cAMP) was measured in matched samples of maternal plasma (MV) and umbilical artery (UA) and vein (UV) of 14 normal infants born following an uncomplicated vaginal delivery. There was good correlation between UA and UV cAMP levels, which seems to indicate that the fetoplacental unit maintains a constant equilibrium of the nucleotide concentration in the umbilical circulation. There was a markedly increased UA cAMP concentration at term relative to that of MV, as well as an arteriovenous gradient of plasma cAMP level (UA greater than UV) in the fetoplacental circulation, which strongly suggest that the high cAMP levels in the cord blood originate mainly from the fetus.

Among 12,500 babies born in our hospital from 1977 to 1982, there was one case of neonatal sepsis due to Group B beta-hemolytic Streptococcus (GBS), an incidence which is significantly lower than that reported in Western countries (3 to 6 per 1,000 live births). Among 385 pregnant women from Jerusalem and Haifa, the vaginal colonization rate with GBS was 2.8%, in contrast with 4.6 to 36% reported in Western countries. Umbilical and ear cultures were obtained from the infants of the 85 mothers who were examined in Haifa. These cultures were repeated at 3 to 5 days of age in 60 of the 85 babies. From the above data, mother-to-infant transmission rates and neonatal nosocomial infection rates with GBS were found to be 66 and 6.6%, respectively, which correlates well with 60 to 75% and 12 to 27% reported in the literature. The low incidence of GBS neonatal sepsis in our survey may be related to the low maternal colonization rate with GBS. The low maternal colonization rate could be related to still unidentified epidemiological and environmental factors.

Bedside demonstration of the absence of the right pulmonary artery was made in a premature baby in the neonatal intensive care unit. Antegrade venous and retrograde aortic injections of contrast material excluded the possibility of the anomalous origin of the right pulmonary artery from the aorta, and suggested the above-mentioned diagnosis, with the addition of a ventricular septal defect and a right-to-left shunt.