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Anesthetized young rabbits were ventilated for 6 hr at 20 cm H2O peak airway pressure using air nebulized with water at 22°C (cold nebulized group, n= 11), at 36°C (warm nebulized group, n= 11) and humidified air at 36°C (warm humidified group, n= 10). Their biochemical status during ventilation and pulmonary morphology at autopsy were compared to those of ten control rabbits. Both nebulized groups had particulate water in the inspired air and water of condensation in the endotracheal tube.

ABSTRACT. Because renal function and electrolyte balance are commonly altered in premature infants, particularly those requiring ventilatory support, we studied the influence of assisted ventilation on renal electrolyte and water excretion in infants with birth weights less than 1501 g during the 2 days after birth. Twenty-two infants receiving assisted ventilation, either as intermittent mandatory ventilation or nasal continuous positive airway pressure, were compared with 21 spontaneously ventilating infants of similar birthweight and gestational age. Mean (and SEM) creatinine clearance was lower (p<0.05) in the assisted ventilation group on day 1 (2.9 ± 0.4 versus 4.1 ± 0.4 ml/min/1.73 m2) and on day 2 (4.1 ±1.0 versus 6.8 ± 0.8 ml/min/1.73 m2, p=0.05), and there was a correlation between creatinine clearance and mean blood pressure in both groups. Mean urine vasopressin was higher in the assisted ventilation group on the first day (360 ± 86 versus 123 ± 30 pg/mg creatinine; p<0.02) and correlated with higher urine osmolality. There were no differences in urine volume, in osmolar or free water clearances, or in the intake and urine excretion of sodium, potassium, and chloride. Plasma renin activity, urine aldosterone, and urine prostaglandin E2were similar in both groups on both days. Neither the mode of assisted ventilation nor the cause of respiratory failure appeared to affect these results.

Amniotic fluid glucose (AF glu) was studied in 92 pregnancies complicated by maternal diabetes. An inverse relation between AF glu and gestational age was found: [AF glu (mg. per deciliter) = 160.9 − 3.51 (weeks gestation); r = −0.47]. A direct relation between AF glu and severity of maternal diabetes was observed: mean AF glu (mg. per deciliter) = 24.6 ± S.D. 12.3 in Class A, 41.2 ± 25.5 in Class AD and 57.5 ± 36.5 in Classes B-D. A positive correlation of AF glu with osmolality was observed [AF Osm (mOsm. per kilogram) = 250.7 + 0.22 AF glu; r = +0.50], but this relation was remarkable inconsistent in individual patients. Neither individual nor serial AF glu levels were of any prognostic value in predicting fetal condition or perinatal outcome.

An outbreak of mild gastroenteritis due to enteropathogenic Escherichia coli 0128: B12 developed in a complex of university hospital nurseries. At least 24 infants were infected with the strain in the 22 days between admission of the index case and initiation of measures to control the outbreak. There were no deaths, disease was mild, and clinically inapparent infection was frequently found. The outbreak abated abruptly after institution of strict aseptic technique, temporary reorganization of the nurseries, and administration of neomycin sulfate to all infants from the newborn nursery in the epidemic cohort.

Body water content and distribution were determined in 16 children aged 2 wk to 28 months before and after open-heart surgery for correction of congenital cardiac defects. Operative procedures were performed using hypothermia and extracorporeal oxygenation. On the day before and the day after surgery, total body water was estimated as the antipyrine space (APS); extracellular water, as the corrected bromide space (CBS), and plasma volume, as the 10-min T-1824-albumin space. Intracellular water (ICW) was assumed to be the difference between APS and CBS; interstitial water was calculated from plasma volume and CBS. Before initiation and after completion of extracorporeal circulation, a pectoral muscle biopsy was performed, and a blood sample was obtained. Muscle total water (TW) content was determined by desiccation, extracellular water (ECW) was estimated as the corrected chloride space, and ICW was assumed to be the difference between TW and ECW. Plasma sodium, potassium, chloride, glucose, and osmolality contents were determined by routine methods. All studies were not completed in all patients.

Midtricipital (MT) and subscapular (SS) skinfolds were measured within 24 hr of birth in 23 normally grown mature (NG-M); 23 normally grown premature (NG-P); 6 intrauterine growth-retarded mature (IGR-M); and 7 intrauterine growth-retarded premature (IGR-P) infants. A rapid initial decrease in measured skinfold thickness (SFT) occurred after application of a Harpenden caliper, but readings stabilized by 60 s (SFT60). Measurements were recorded at 15 and 60 s. The difference between 15− and 60-s readings was expressed in percentage of the 15-s reading (percentage ASFT).

Fifteen of 20 infants surviving perinatal asphyxia (Apgar ≤ 3) necessitating resuscitation with positive-pressure oxygen and intravenous buffer were compared with 14 healthy mature nonasphyxiated infants 15 to 40 months after birth. Ten asphyxiated and 11 nonasphyxiated infants had normal neurologic examinations while two asphyxiated and three nonasphyxiated babies had borderline results. The three intrauterine growth-retarded babies in the asphyxia group all had neurologic deficits. Excluding these three badly damaged growth-retarded babies (mean I.Q. = 31), mean I.Q. scores of asphyxiated and nonasphyxiated groups were identical (96, asphyxiated; 96, nonasphyxiated). These preliminary data suggest a good prognosis for acutely asphyxiated infants managed with current techniques of resuscitation.

Amniotic fluid (AF) lecithin/sphingomyelin (L/S) ratios were obtained in 223 pregnancies. Gestations complicated by maternal diabetes (71), vascular disease (50), and fetal growth retardation (47) were included. Elevated L/S ratios at 34 to 36 weeks' gestation were observed to accompany maternal vascular disease; higher ratios were also related to fetal sex (female) and race (black). Declining L/S ratios were observed in 14 of 35 diabetic patients studied serially (40 per cent) and were accompanied by increased perinatal morbidity and deaths. These data suggest an urgent need for further studies concerning the clinical usefulness of a serial decline in the L/S ratio as a predictor of fetal compromise.

Summary: Body water content and distribution were determined in 16 children aged 2 wk to 28 months before and after open-heart surgery for correction of congenital cardiac defects. Operative procedures were performed using hypothermia and extracorporeal oxygenation. On the day before and the day after surgery, total body water was estimated as the antipyrine space (APS); extracellular water, as the corrected bromide space (CBS), and plasma volume, as the 10-min T-1824-albumin space. Intracellular water (ICW) was assumed to be the difference between APS and CBS; interstitial water was calculated from plasma volume and CBS. Before initiation and after completion of extracorporeal circulation, a pectoral muscle biopsy was performed, and a blood sample was obtained. Muscle total water (TW) content was determined by desiccation, extracellular water (ECW) was estimated as the corrected chloride space, and ICW was assumed to be the difference between TW and ECW. Plasma sodium, potassium, chloride, glucose, and osmolality contents were determined by routine methods. All studies were not completed in all patients.Although APS and CBS increased in eight of 11 children, mean APS (± S.E.) before and after surgery (662 ± 28.0 versus 714 ± 37.2 ml/kg) and mean CBS (335 ± 30.5 versus 358 ± 15.5 ml/kg) were not statistically different. Mean ICW changed neither in relation to body weight (328 ± 28.0 versus 355 ± 34.2 ml/kg) nor in relation to APS (ICW/APS ratio = 0.48 ± 0.040 versus 0.49 ± 0.010). Neither mean PV (54 ± 4.0 versus 56 ± 2.8 ml/kg) nor mean blood volume (92 ± 5.4 versus 90 ± 5.5 ml/kg) changed significantly. Mean interstitial water increased by 9 to 68% over preoperative values in all but one patient (238 ± 10.4 versus 305 ± 13.4 ml/kg; P < 0.01).Muscle composition was not affected by the procedure. Mean TW was 79 ± 1.3 ml/100 g before extracorporeal circulation and 78 ± 0.8 ml/100 g afterwards whereas ECW averaged 32 ± 4.4 and 36 ± 3.4 ml/100 g, and ICW averaged 48 ± 4.6 and 42 ± 2.9 ml/100 g. Mean ICW/TW ratios were 0.60 ± 0.055 and 0.54 ± 0.040 ml/100 g.Although mean plasma sodium (142 ± 3.5 versus 139 ± 2.4 mEq/liter) and potassium (3.3 ± 0.16 versus 3.6 ± 0.15 mEq/liter) concentrations did not change appreciably during extracorporeal circulation; mean plasma chloride content decreased (108 ± 2.9 versus 100 ± 2.0 mEq/liter; P < .002). Plasma glucose averaged 60 mg/dl more at completion of the procedure, increasing from a mean of 223 ± 25.6 mg/dl to a mean of 283 ± 5.3 mg/dl (P < 0.05). Plasma osmolality increased in five of eight children, but mean osmolalities were similar before and after extracorporeal circulation (301 ± 8.9 versus 303 ± 5.4 mOsm/kg).These data suggest that a child's organism does not react complacently to the invasive procedures associated with open-heart surgery. Further research into effects of these procedures and into means of minimizing undesirable homeostatic disturbances is warranted.Speculation: Body composition of adult patients has been shown to be acutely altered by open-heart surgery with hypothermia and extracorporeal circulation. Our data suggest that similar changes occur in young children who are subjected to these procedures. Because small children, especially those afflicted with major congenital defects, have limited homeostatic capabilities, the risk of these disturbances becoming life-threatening is increased. Means of minimizing them need be devised.

Continuous positive airway pressure (CPAP) was employed using nasal prongs in 30 neonates with hyaline membrane disease (HMD). There was a significant improvement in mean Pa02 (from 47 to 80 mmHg; p < 0.001) with no significant change in PaCO2 or pH within a mean 36 min of therapy. Use of the technique allowed reduction of FiO2 to < 0.60 in < 20 h in 18 infants. Infants treated within 24 h of birth had significantly greater improvements in PaO2. Complications were infrequent and only 3 of 30 babies developed a pneumothorax while on nasal CPAP. Only 1 of the 23 survivors required mechanical ventilation in addition to nasal CPAP.

61 intravenous glucose tolerance tests (GTT) were performed within 24 h of birth in 50 infants of birth weights 500–1,380 g. Glucose exposure prior to the test in 33 of the GTT resulted in higher mean plasma glucoses, more frequent preinfusion hyperglycemia (glucose > 125 mg/100 ml), and a greater proportion of slower glucose disappearance rates (Kt) when compared to the 28 ‘fasting’ infants who received no glucose prior to the test. In seven of the fasting tiny babies, two immediately successive (‘double’) GTT were performed within 8.5 h of birth. Contrary to all previously reported studies in healthy adults and mature newborns, these babies failed to demonstrate an increased rate of glucose disappearance and signifanctly lower plasma glucoses in the initial phase of the second test. These unique findings help explain previous observations from this laboratory of significant hyperglycemia in infants of very low birth weight and further document their vulnerability to hyperglycemia with parenteral glucose infusions.

Of 17 neonates with systemic, group B, β-hemolytic streptococcal infection, all but one died. Absence of prenatal or neonatal warnings of infection was striking, with only two patients having prolonged rupture of fetal membranes. Most were tiny, normally grown, premature infants and all had a low birth weight. Laboratory aids to early diagnosis (histological characteristics of the cord and IgM level) were notably absent, and the usual signs and symptoms suggesting neonatal infection were rare. Unexplained apneic episodes were common within three to four hours of birth in most infants. Coagulation disorders were detected before death in two infants and extensive hemorrhage was the most prominent autopsy finding. Neonatal infection with group B, β-hemolytic streptococcus appears to be a common lethal disorder that strikes with but little advance warning.

Amniotic fluid (AF) creatinine concentrations, determined in 353 samples from 167 pregnancies complicated by maternal diabetes, are similar to those found at comparable gestation in uncomplicated pregnancy. Added maternal vascular disease significantly raises AF creatinine to such a degree that overestimation of fetal (renal) maturity is a clinical hazard if based solely on this parameter. Relative concentrations of creatinine in AF and maternal plasma (AF/MP ratio) are related to gestational age. Failure of AF creatinine to rise consistently on successive serial samples accompanies an increased risk of perinatal death in the pregnancy complicated by diabetes, four of five deaths in the present series following declines in this measurement.

Amniotic fluid osmolality (AF Osm) was studied in 247 patients whose pregnancies were complicated by maternal diabetes. Significant increases in mean AF Osm accompanied pre-existing fetal as well as subsequent perinatal death. Abnormal increases in AF Osm were associated with a significant increase in risk of perinatal compromise with cumulative morbidity and mortality rates of 54 per cent. These data suggest that serial evaluation of AF Osm enables detection of a “higher risk” group of diabetic pregnancies in which perinatal death is more than doubled.

Amniotic fluid volume estimates were obtained in 37 diabetic women at 33½–38½ weeks of gestation. The technique employed, sodium aminohippurate (PAH) dilution, allowed estimation of both volume and Ê»turnover’. Hydramnios was common in the patients studied earlier in their third trimester; fetal macrosomia and increased severity of maternal disease was also evident in this group. Volumes comparable to those reported from normal patients were observed in the women studied later in their third trimester. Amniotic fluid volume appeared to be related to fetal growth with hydramnios accompanying macrosomia and oligohydramnios in fetal growth retardation. A positive correlation of PAH clearance and amniotic fluid volume was found.

We developed and evaluated a transducer holder and calibrated, spring-loaded applicator for the Ladd intracranial pressure monitor. The transducer holder/applicator combination allows reproducibility of application pressure and assures coplanarity of the transducer and the skin of the anterior fontanel. Measured transfontanel pressure (TFP) increased with increasing application pressure. Mean TFP was 9.1 ± (SD) 2.6 cm H2O with an application pressure of about 10 g/cm2 in a group of healthy preterm and term infants at 6 h postnatal age. Birth weight, gestational age and mode of delivery did not affect TFP, allowing use of a single normative value and set of confidence limits in all infants at 6 h of postnatal age.

• Colloid osmotic pressure was measured at birth in 102 newborns. Umbilical vein plasma colloid osmotic pressure correlated with total serum protein, birth weight, and gestational age. Mean colloid osmotic pressure of 11 infants who were small for gestational age was less than, and that of seven infants who were large for gestational age was more than, that of average-sized infants of similar gestation. For infants weighing 1,501 to 3,000 g, mean (±SD) colloid osmotic pressure following cesarean section (15.1±1.6 mm Hg) was lower than that following vaginal delivery (18.4±2.2 mm Hg). This may reflect the fact that use of maternal fluid therapy preceding cesarean section was greater than before vaginal delivery. The definition of normative values for neonatal plasma colloid osmotic pressure makes it possible to investigate changes in relation to disease, therapy, and subsequent outcome in sick neonates.(Am J Dis Child 1983;137:674-677)

• Bacteria were identified in 126 blood and CSF cultures obtained in 311 consecutive neonatal deaths (41%). These postmortem cultures were of diagnostic value, providing the sole means for definitive bacteriologic diagnosis in 82 (65%) of the 126 infected infants. Similarity of organisms found in specimens before and after death (identical in 25 of 26), similar identity of organisms identified by histologic Gram's stain and culture (the same in 48 of 49), and the identical nature of organisms identified from blood and CSF sites (the same in 43 of 43) support the validity of these cultures. Bacterial infection remains a serious problem in neonatal intensive care. The scope of this problem may be underestimated if postmortem cultures are not obtained.(Am J Dis Child 1983;137:645-649)