Weight-bearing patterns on the knees of preterm infants.

In this study we present a method of monitoring the forces under the knees of preterm infants lying in the prone position. Dual force sensing resistor transducers, connected to optically-isolated amplifiers, were used to monitor the forces. A thermistor airflow sensor was used for the parallel monitoring of the respiratory signal. The measurements were made on ten preterm infants. The average forces were 0.51 and 0.50 N for the left and right knees, respectively. In the frequency domain, the basic harmonic of the force traces was 1.27 Hz approximately, corresponding to the respiratory rhythm. Additional, smaller harmonics, were detected in the force traces at 2.54 and 3.81 Hz. A rather notable power signal could also be seen around 0.1 Hz. The results obtained indicate that the system developed is highly sensitive for providing data on the amplitudes, periods and sequences of oscillations and symmetry of load bearing in preterm infants. Knowledge of the normal and abnormal reaction force patterns may assist in the early diagnosis of abnormal neurodevelopment.

Lipid infusion with different triglyceride cores (long-chain vs medium-chain/long-chain triglycerides): effect on plasma lipids and bilirubin binding in premature infants.

The possible beneficial effects of infusing a lipid emulsion containing 50% by weight of medium-chain triglycerides (MCT) compared with a standard long-chain triglyceride (LCT) emulsion were studied in 18 premature neonates (gestational age less than 34 weeks) requiring parenteral nutrition. The infants were assigned in a double-blind manner to receive one of the two lipid emulsions over 17 hours a day as a supplemental regimen for total parenteral nutrition. A lipid load of 1 g/kg per day was initiated on the third day of life and was increased at the rate of 1 g/kg per day until a maximal dose of 3 g/kg per day was obtained on the fifth day of life and maintained thereafter. Both bound and unbound bilirubin decreased with both infusion regimens during the study period. Despite a marked increase in plasma free fatty acid levels (260% in the MCT/LCT group compared with 210% in the LCT group), the fraction of unbound (free) bilirubin was significantly lower in the MCT/LCT group (34% vs 13%). Free fatty acid levels, corrected to albumin, were positively correlated to the percentage of free bilirubin only for the LCT lipid infusion. The finding of a significant elevation of plasma cholesterol levels only in the MCT/LCT group is now under investigation. Use of the MCT-containing emulsion was not associated with a higher frequency of adverse effects than the commonly used LCT-containing emulsion.(ABSTRACT TRUNCATED AT 250 WORDS)

Normal ranges of hip motion of preterm infants.

The hip motion of 158 preterm infants with gestational ages between 25 and 36 weeks was measured. The results of this study, compared with those of previous studies of term infants, show that hip motion changes with increasing gestational age above 25 to 27 weeks.

Evaluation of bilirubin as possible protective factor in the prevention of retinopathy of prematurity.

Retinopathy of prematurity (ROP) appears to be a multifactorial disease, the prevention of which is probably impossible even with the most accurate methods of blood-gas monitoring and oxygen restrictions. The oxidative processes and consequent formation of free radicals are probably influenced by the availability of various antioxidants in the immature retina. Bilirubin, the end product of haem catabolism, has recently been regarded as a potential physiological antioxidant. In order to test the suggestion as to the possible effect of bilirubin in reducing the incidence of ROP a retrospective study was undertaken of the medical records of 151 neonates born between 1984 to 1988 who weighed less than 1500 g. Of these, 78 had various degrees of ROP, whereas 73 had no ROP and served as a control group. The daily mean bilirubin values were analysed in accordance with gestational age and birth weight as well as the severity of ROP, and the results were compared with those obtained for the control group. The results showed no correlation between bilirubin levels and severity of ROP in all subgroups of gestational age and birth weight. These findings indicate that there is no apparent protective effect of bilirubin on the development of ROP.

Effect of neonatal posture on later lower limb rotation and gait in premature infants.

The rotational profile of 265 children age 4-8 years who were born at the gestational age of less than or equal to 30 weeks and were nursed prone for several months after birth showed a marked outtoeing gait up to the age of 6 years. Their positive thigh-foot angles were significantly higher than those of the general population. These angles indicate that their outtoeing gaits were caused by marked external tibial rotation.

Eleven years' experience with retinopathy of prematurity: visual results and contribution of cryoablation.

We report our 11 years' experience of cryotherapy for retinopathy of prematurity (ROP). Charts of 624 infants weighing under 1250 g who were admitted to our Neonatal Intensive Care Unit during 1977-87 were reviewed. Three hundred and eighty nine babies survived, and the total ROP prevalence was 57.5%. Cryotherapy was applied to 35%. Only one case (0.25%) of blindness was detected, and four babies (1%) had a final visual acuity of less than 20/200 in one eye. The complication rate following cryoablation was very low.

Rotational deformities of the tibia and foot in preterm infants.

Metatarsus adductus and medial tibial torsion are common in term infants. Our study shows that metatarsus adductus is rare, whereas medial tibial torsion does not occur in preterm infants with gestational ages of less than or equal to 30 weeks. These preterm infants have lateral rotation of the legs, external tibial rotation, and everted or normal feet at birth. This posture may explain the rarity of metatarsus adductus and medial tibial torsion in preterm infants.

Energy intake, growth, and development in ventilated very-low-birth-weight infants with and without bronchopulmonary dysplasia.

Seventy-one ventilated very-low-birth-weight infants (birth weight, 500 to 1250 g) with (n = 30) and without (n = 41) bronchopulmonary dysplasia were studied to compare their growth achievements and to determine the association between neurodevelopmental outcome, growth, and nutrition. Growth delay was observed in both groups. No association was found between head circumference and percent weight loss, age to full gavage feeds, age to regain birth weight and energy intake at 2 and 4 weeks of life. Fifty percent of infants with bronchopulmonary dysplasia and 37% of the control group had minor and major handicap. Mean duration of assisted ventilation was significantly longer in handicapped infants (21.5 vs 12.5 days; F = 6.49; df = 1,53). No association was found between abnormal neurodevelopmental outcome and weight, length, and head circumference at 12 and 21 months after term. Although mean energy intake per kilogram per day at 2 weeks of life was significantly lower in handicapped infants (344.82 vs 412.86 kJ; F = 7.6; df = 1,53), age to regain birth weight, age to full feeds, percent weight loss, and energy intake at 4, 6, and 8 weeks of life did not differ significantly between normal and handicapped infants. Aggressive nutritional support to promote growth in ventilated very-low-birth-weight infants may not influence the neurodevelopmental outcome.

Necrotizing enterocolitis after intravenous immunoglobulin treatment for neonatal isoimmune thrombocytopenia.

A male neonate of 38 weeks' gestation with isoimmune neonatal thrombocytopenia treated with high dose intravenous immunoglobulin (IVIG) developed necrotizing enterocolitis (NEC) at 3 days of age. The known maternal and neonatal risk factors for the development of this disease were excluded. The association between high dose IVIG and the appearance of thrombotic events might be another aetiological factor for occurrence of NEC in a newborn infant.

Pulmonary interstitial emphysema in low birth weight infants: characteristics of survivors.

Twenty out of 303 ventilated low birth weight infants, hospitalized in the Beilinson Medical Center's Intensive Care Unit, during the years 1984-1986, developed pulmonary interstitial emphysema. Eighteen infants had very low birth weight (less than 1500 grams) and 17 were less than 30 weeks' gestation. The mean birth weight was 987 +/- 311 and mean gestational age 27.7 +/- 2.5. Eight infants survived the pulmonary disease. There were no significant differences in the neonatal parameters between infants who died or survived. However, the survivors had a significantly lower maximal peak inspiratory pressure and FiO2 on the first day of ventilation. The incidence of pneumothorax and asphyxia was the same in both groups.

Failure of etretinate therapy in twins with severe congenital lamellar ichthyosis.

We cared for twin females with severe lamellar exfoliation of the newborn (collodion babies) and a family history of death of two brothers at age 3 months. The twins were given a controlled trial of etretinate (Ro 10-9359, Tigason) after not responding to other therapeutic modalities. One of the infants received 1 mg/kg body weight of the drug for 24 hours, while her identical twin sister did not have the medication. Monthly skin biopsies taken from both patients during nine months of therapy did not demonstrate any histologic difference under light microscopy. The clinical course in both infants was basically the same. Etretinate plasma level measurements proved that the drug was absorbed from the gastrointestinal tract. We conclude that in the very severe forms of congenital lamellar ichthyosis, oral retinoids may fail to produce any beneficial effects.

Fractures in premature infants.

Fractures not related to birth trauma were diagnosed in 1.2% of preterm infants between the 24th and the 160th day of life. The clinical and radiologic findings as well as the follow-up on 12 preterm infants with one or more fractures were reviewed. Fractures occurred either in the ribs or long bones or both. Their clinical history, the radiographic appearance, and laboratory data suggest that most of the infants may have suffered from bone loss associated with low intake of calcium and phosphorus. Improving the metabolic status and removing the risk factors prevented further fractures and led to good healing.

Group B streptococcus amnionitis with intact membranes associated with quintuplet delivery.

Chorioamnionitis is a frequent cause of premature labour and delivery, as well as of maternal and neonatal mortality. Group B streptococcus (GBS) has emerged over the past decade as a common pathogen in the etiology of neonatal sepsis. The case of chorioamnionitis reported here is unusual for three reasons: the premature labour was associated with intact membrane and amniotic fluid infected with GBS; all 5 infants were contaminated with GBS and all infants survived. Chorioamniotitis with intact membranes raises some questions regarding the antepartum use of steroids (potent anti-inflammatory agents), etc. The likelihood of chorioamnionitis in spite of cervical mucus, intact membranes, and the bacteriostatic activity of the amniotic fluid should alert the obstetrician to take special precautions, such as weekly vaginal cultures and appropriate vaginal antimicrobial treatment, in cases of imminent premature delivery.

Plasma ammonia levels in preterm infants receiving parenteral nutrition with crystalline L-amino acids.

In order to investigate the severity and incidence of hyperammonemia in preterm infants receiving total parenteral nutrition (TPN) with crystalline L-amino acids having high arginine content (Travasol), we determined the plasma ammonia (PA) levels in a group of 29 preterm infants on TPN, weekly and 1 wk posttherapy. Their mean gestational age was 29.9 +/- 2.6 wk and mean birth weight 1208 +/- 262 g. Thirty five blood samples obtained from 15 preterm infants not on TPN with mean gestational age 32.2 +/- 1.9 wk and a birth weight of 1495 +/- 161 g served as a control. In the parenteral nutrition group the mean PA level (140 +/- 58 micrograms/100 ml) was significantly higher (p less than 0.001) than that in the same group one week post TPN (97 +/- 34 micrograms/100 ml) and in the control group (86 +/- 35 micrograms/100 ml). The incidence of hyperammonemia (greater than 160 micrograms/100 ml) was 30% in the TPN group versus 3% in the controls (p less than 0.01). Maximal PA level during that treatment was 405 versus 216 micrograms/100 ml 1 wk post-TPN versus 163 micrograms/100 ml in the controls. The data show a significant increase in PA levels in preterm infants receiving TPN with Travasol, possibly because of its high glycine content.