Luis Pereira-da-Silva

Early high calcium and phosphorus intake by parenteral nutrition prevents short-term bone strength decline in preterm infants.

Background and Aim: Very premature newborns have an increased risk of low bone mass and metabolic bone disease. Most longitudinal studies report a significant decline in bone strength in the first weeks after birth. The aim of the study was to evaluate whether higher early calcium (Ca) and phosphorus (P) intake delivered by parenteral nutrition (PN) can prevent bone strength decline in preterm infants, within the first weeks after birth. Patients and Methods: This was a randomized controlled trial of consecutively admitted neonates born with ≤33 weeks of gestational age, assigned to receive either Ca 45 mg · kg−1 · day−1 (low dose [LD]) or Ca 75 mg · kg−1 · day−1 (high dose [HD]) by PN. P was added to the PN solutions at a fixed Ca:P ratio (mg) of 1.7:1. Bone strength was assessed by the speed of sound (SOS) using the quantitative ultrasound method. Measurements were performed weekly from birth until discharge. Low bone strength (SOS <10th centile of reference values) was the main outcome. Results: Eighty-six infants were enrolled, 40 assigned to LD group and 46 to HD group. Mean (standard error) gestational age was 29.6 weeks (2.1) and birth weight was 1262 g (0.356). In the HD group, the SOS values never fell below those recorded at birth and, up to the sixth week of life, low bone strength was significantly less frequent as compared with that in the LD group, in spite of progressive reduction in parenteral mineral intake and/or establishment of full enteral feeding. Conclusions: Early assigned parenteral intake of Ca 75 mg · kg−1 · day−1 and P 44 mg · kg−1 · day−1 significantly contributed to preventing short-term bone strength decline in preterm infants.

A simple equation to estimate the osmolarity of neonatal parenteral nutrition solutions.

UNLABELLED A predictive equation of osmolarity that correlates closely with the measured osmolality was determined. Taking into account that an osmometer is not available in most clinical settings, the proposed equation appears to provide a quick and simple osmolarity calculation of neonatal parenteral nutrition solutions. OBJECTIVE We measured the osmolalities of neonatal parenteral nutrition (PN) solutions to determine if these values may be predicted by a simple equation for calculation of their osmolarity values. METHODS The osmolalities of 101 consecutive different final PN admixtures, prepared for 36 neonates, were measured by the freezing point depression method. The respective intra-assay and interassay coefficients of variation were always <2.1%. Linear multivariate regression analysis was used to determine a predictive equation of osmolarity that correlates closely with the value of measured osmolality. RESULTS The mean (SD) osmolality of the final PN admixtures was 749.7 (165.4) mOsm/kg. The best-fitted equation, with a coefficient of discrimination R2 = .95 (R2 = .90 for samples between 500 and 1000 mOsm/L) is osmolarity (mOsm/L) = (nitrogen x 0.8) + (glucose x 1.235) + (sodium x 2.25) + (phosphorus x 5.43)-50, with the concentration of components in mmol/L. Adapting the equation in our daily practice, using g/L for glucose and amino acids, mg/L for phosphorus, and mEq/L for sodium, the equation is osmolarity (mOsm/L) = (amino acid x 8) + (glucose x 7) + (sodium x 2) + (phosphorus x 0.2) - 50, with a similar R2. CONCLUSIONS Taking into account that an osmometer is not available in most clinical settings, the proposed equation appears to provide a quick and simple osmolarity calculation of neonatal PN solutions, thus allowing more accurate decisions to be taken regarding the choice of route and rate of administration of PN solutions.

Skin conductance indices discriminate nociceptive responses to acute stimuli from different heel prick procedures in infants

Aim: To evaluate the ability of SC indexes in discriminating acute responses to different heel prick procedures. Methods: Observational cohort study of a systematic, convenience sample of neonates with clinical indication of capillary blood sampling by heel prick, either for glycaemia or for blood gas analysis. The Neonatal Infant Pain Scale (NIPS) was used to confirm the painful nature of the stimuli. NIPS assessment and SC measurement (Med-Storm Pain Monitor™) were simultaneously performed by two independent observers before, during and after blood sampling. Results: Sixty-eight heel prick procedures (46 for glycaemia and 22 for blood gas analysis) were applied to 16 infants. Both NIPS scores and SC peaks/s index were significantly higher during blood sampling than before or thereafter (Wilcoxon Signed Ranks, p < 0.001). There was no significant difference in NIPS score and SC peaks/s between the different heel prick procedures. Significantly higher SC area under low peaks index (Mann–Whitney, p = 0.001) and lower SC average rise time index (Mann–Whitney, p = 0.037) were registered when blood was drawn for blood gas analysis than for glycaemia, related to a sustained acute nociceptive response to a more prolonged stimulus. Conclusion: Using the conjunction of available SC indices, SC seems able to differentiate the nociceptive response to acute pain of different durations.

The adjusted effect of maternal body mass index, energy and macronutrient intakes during pregnancy, and gestational weight gain on body composition of full-term neonates.

OBJECTIVE To evaluate the effect of prepregnancy body mass index (BMI), energy and macronutrient intakes during pregnancy, and gestational weight gain (GWG) on the body composition of full-term appropriate-for-gestational age neonates. STUDY DESIGN This is a cross-sectional study of a systematically recruited convenience sample of mother-infant pairs. Food intake during pregnancy was assessed by food frequency questionnaire and its nutritional value by the Food Processor Plus (ESHA Research Inc, Salem, OR). Neonatal body composition was assessed both by anthropometry and air displacement plethysmography. Explanatory models for neonatal body composition were tested by multiple linear regression analysis. RESULTS A total of 100 mother-infant pairs were included. Prepregnancy overweight was positively associated with offspring weight, weight/length, BMI, and fat-free mass in the whole sample; in males, it was also positively associated with midarm circumference, ponderal index, and fat mass. Higher energy intake from carbohydrate was positively associated with midarm circumference and weight/length in the whole sample. Higher GWG was positively associated with weight, length, and midarm circumference in females. CONCLUSION Positive adjusted associations were found between both prepregnancy BMI and energy intake from carbohydrate and offspring body size in the whole sample. Positive adjusted associations were also found between prepregnancy overweight and adiposity in males, and between GWG and body size in females.

Clinical evidence of vascular abnormalities at birth in Adams-Oliver syndrome: report of two further cases.

We read with interest the recent article by Swartz et al. [1999] on vascular abnormalities in Adams-Oliver syndrome (AOS). Although the pathogenesis of this predominantly autosomal-dominant syndrome remains unclear, it has been suggested [Hoyme et al., 1982] that intrauterine vascular disruption involving small-caliber vessels may be responsible for terminal transverse limb defects. It is possible that vulnerable areas such as the embryonic skin mechanically stretched by rapid brain or limb growth may be affected predominantly by this vascular disruptive mechanism [Pousti and Bartlett, 1997]. According to the hypothesis that interrupted blood supply to the developing structures occurring early in fetal life [Fryns et al., 1996], signs of vascular compromise would not be expected in an infant affected with AOS born at term. The recent admission to our unit of two patients with AOS, one of them with clinical evidence of distal vascular limb compromise at birth, prompts us to report these cases. Patient 1 was a female born on May 31, 1999, at 36 weeks’ gestation after an uncomplicated pregnancy and delivery. Family history was unremarkable. Her birthweight was 2,500 g (25th centile). She was found to have a midline scalp defect of both skin and bone 3 × 5 cm in diameter on the parieto-occipital region, with an intact dura. Her right hand had 2–4 syndactyly and absence of distal phalanges of the 3rd and 5th fingers; her left foot had talipes equinovarus. Her karyotype was normal (46,XX). Patient 2 was another female born June 6, 1999, at 34 weeks’ gestation to a nonconsanguineous 44-yearold mother and a 27-year-old father. Her grandmother was born without nails. Amniocentesis performed for chromosomal analysis showed a normal 46,XX karyotype. Delivery was by cesarean section and birthweight was 1,395 g, length 39 cm, and OFC 26 cm (symmetrical IUGR). An extensive scalp and skull defect was present at birth involving most of parieto-occipital region, with large vascular plaques with atrophy and necrosis; the dura was apparently intact. Her fingertips were necrotic, involving the nails (Fig. 1); the toes were apparently “amputated,” and there was evidence of distal ischemia of metatarsal regions (Fig. 2). She also had generalized cutis marmorata telangiectatica, localized ulceration of the abdominal skin, and dilated veins on the trunk. No other malformations were detected. Within 2 weeks after birth, healing of the ischemic le-

Reducing Discomfort While Measuring Crown-Heel Length in Neonates

AIM To assess the degree of discomfort caused by length measurement in neonates, performed with one or both lower limbs extended, on the first and second day after birth, with either one or both lower limbs extended. METHODS Healthy full-term neonates were systematically sampled during the months of February and March 2004. Crown-heel length was measured, using a 1-mm precision neonatometer, at approximately 8 h and 32 h after birth, with one and both lower limbs extended. The Neonatal Facial Coding System was used to assess discomfort during measurements. Data were analysed by parametric and non-parametric tests as appropriate. RESULTS Whatever the measurement technique, discomfort scores are significantly higher during the length measurement than at baseline. Whenever length measurements are performed, discomfort scores are significantly higher when extending both lower limbs rather than one lower limb (p < 0.006). The measured length is greater with one lower limb extended; however, the difference decreases over time, being 0.19 cm (95% CI 0.1-0.3; p < 0.001) at approximately 32 h of age. No significant differences in length were found between measurements at approximately 8 or 32 h, regardless of the technique used. The best correlation between length measurements with one or both lower limbs extended was observed at approximately 32 h after birth (r = 0.98). CONCLUSION Measuring crown-heel length is a distressful procedure for the neonate. Measurements with one lower limb extended result in less discomfort than when both lower limbs are extended, without decreasing the accuracy.

Is Intrauterine Growth Appropriate to Monitor Postnatal Growth of Preterm Neonates

When using the useful 2013 Fenton Chart, data should be interpreted with caution taking into account two aspects: the physiologic loss of body water after birth for the weight curves, and the questionable accuracy of the birth length curves considering the heterogeneity and reliability of the methods used in the original measurements.

Osmolality of elemental and semi-elemental formulas supplemented with nonprotein energy supplements.

BACKGROUND Elemental and semi-elemental formulas are used to feed infants with short bowel syndrome, who may not be able to tolerate feeds of more than 310 mOsm kg(-1). The present study aimed to measure the osmolality of elemental and semi-elemental formulas at different concentrations, with and without the addition of nonprotein energy supplements. METHODS The osmolality of one elemental and three semi-elemental formulas was measured by the freezing point depression method at concentrations of 10, 12, 14 and 16 g per 100 mL, with and without 10% or 20% of additional calories, in the form of glucose polymers and medium chain triglycerides. Inter-analysis and intra-analysis coefficients of variation of the measurements were less than 3.9%. RESULTS The mean osmolalities of formulas reconstituted up to 12 g per 100 mL did not exceed 305.3 mOsm kg(-1), even with added energy supplements. The mean osmolalities of formulas at 14 and 16 g per 100 mL, with or without added energy supplements varied between 205.8 and 421.6 mOsm kg(-1). CONCLUSIONS A comprehensive list of elemental and semi-elemental formulas at different concentrations, enriched or not with calories, is made available. This will enable professionals to customize feeds with the optimum composition, without exceeding the osmolality suggested for infants with short bowel syndrome.

Osmolality of solutions, emulsions and drugs that may have a high osmolality: aspects of their use in neonatal care

Objective: Administration of some hypertonic substances to neonates has been associated with a variety of adverse effects. This study was conducted to determine the osmolality of intravenous drugs and solutions used in neonates receiving intensive care. Methods: Osmolality was measured by freezing point depression. Vasoactive drugs, diuretics, anticonvulsants, antimicrobials, and glucose and electrolyte solutions were some of the substances analyzed. Results: The osmolalities of 90 substances were measured; the respective intra-assay and interassay coefficients of variation were always less than 5%. A few drugs were found to be extremely hypertonic (> 8000 mOsm/kg), and most of them contain propylene glycol as vehicle (e.g. digoxin, phenytoin, diazepam and phenobarbital). Other drugs, at the same concentration, evidenced a significant discrepancy of osmolality depending on the trademark. Conclusions: The finding of some extremely hypertonic drugs highlights the need for further investigation in order to study their potential adverse effects in neonates, as well as to evaluate any advantage in diluting, infusing slowly or even avoiding such substances. Given the fact that there exists a discrepancy in osmolalities in some drugs at the same concentration depending on the trademark, the more isotonic solutions should be the preferred choice for intravenous administration.

Upper arm measurements of healthy neonates comparing ultrasonography and anthropometric methods

OBJECTIVE To compare measurements of the upper arm cross-sectional areas (total arm area, arm muscle area, and arm fat area of healthy neonates) as calculated using anthropometry with the values obtained by ultrasonography. MATERIALS AND METHODS This study was performed on 60 consecutively born healthy neonates: gestational age (mean+/-SD) 39.6+/-1.2 weeks, birth weight 3287.1+/-307.7 g, 27 males (45%) and 33 females (55%). Mid-arm circumference and tricipital skinfold thickness measurements were taken on the left upper mid-arm according to the conventional anthropometric method to calculate total arm area, arm muscle area and arm fat area. The ultrasound evaluation was performed at the same arm location using a Toshiba sonolayer SSA-250A, which allows the calculation of the total arm area, arm muscle area and arm fat area by the number of pixels enclosed in the plotted areas. STATISTICAL ANALYSIS whenever appropriate, parametric and non-parametric tests were used in order to compare measurements of paired samples and of groups of samples. RESULTS No significant differences between males and females were found in any evaluated measurements, estimated either by anthropometry or by ultrasound. Also the median of total arm area did not differ significantly with either method (P = 0.337). Although there is evidence of concordance of the total arm area measurements (r = 0.68, 95% CI: 0.55-0.77) the two methods of measurement differed for arm muscle area and arm fat area. The estimated median of measurements by ultrasound for arm muscle area were significantly lower than those estimated by the anthropometric method, which differed by as much as 111% (P < 0.001). The estimated median ultrasound measurement of the arm fat was higher than the anthropometric arm fat area by as much as 31% (P < 0.001). CONCLUSION Compared with ultrasound measurements using skinfold measurements and mid-arm circumference without further correction may lead to overestimation of the cross-sectional area of muscle and underestimation of the cross-sectional fat area. The correlation between the two methods could be interpreted as an indication for further search of correction factors in the equations.