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N
utritional
practices
and
postnatal
growth
restriction
in
preterm
newborns
R
ev
A
ssoc
M
ed
B
ras
2015; 61(6):500-506
501
M
ethods
This was a retrospective analysis of the medical records
of premature infants born between January 2000 and
December 2005 in a public teaching hospital. Preterm
infants with birth weight (BW) between 500 and 1,499 g
admitted to the neonatal intensive care unit at Hospital
São Paulo were considered eligible. The exclusion crite-
ria were death ≤ 7 days, major congenital anomalies and
genetic syndrome. The study was evaluated by the Eth-
ics Committee of the Universidade Federal de São Pau-
lo, which considered signing the informed consent form
unnecessary.
The data included about the newborns were gesta-
tional age, sex, birth weight, small for gestational age
(SGA) characterized as birth weight below the 10
th
per-
centile (Alexander et al, 1996)
12
and resuscitation in the
delivery room. The morbidities analyzed were respirato-
ry distress syndrome (RDS), sepsis, necrotizing enteroco-
litis (NEC), patent ductus arteriosus (PDA), peri-intra-
ventricular hemorrhage (PIVH) grades III and IV,
bronchopulmonary dysplasia (BPD) and frequency of
SGA at post-conceptual age of term (weight below the
10
th
percentile).
The drugs and procedures analyzed were use of sur-
factant, indomethacin, corticosteroids, mechanical ven-
tilation and central venous catheter.
Bodyweight was recorded daily in accordance with
the recommended standards. The maximum percentage
of weight loss, time to regain birth weight, daily weight
gain after recovery of birth weight and the number of
days to reach 1800 grams were calculated.
Nutritional data were recorded daily and included
the period between birth and a weight of 1800 g. For par-
enteral nutrition (PN) the start date, duration, and max-
imum initial supply of glucose, protein, lipid and energy
were collected. For enteral nutrition (EN), characterized
by infusion of the diet via gastrostomy tube, the type of
diet, start date and number of days of minimal enteral
nutrition use (≤10 mL/kg/day, without increments), days
to achieve exclusive enteral nutrition and energy supply
of 120 kcal/kg/day were recorded.
Nutritional therapy was prescribed by the attending
physicians, according to routine of the neonatal intensive
care unit during the study period. PN and EN should be
initiated within the first 48 hours of life. The recommen-
dations established for PN were 80 kcal/kg/day of energy,
maximum initial supply of glucose 6 g/kg/day and 16 to
18 g/kg/day, respectively; amino acids and lipids starting
within 48 hours of birth and initial doses, increments and
maximum supply of 1.0, 1.0 and 3.5 g/kg/day of amino ac-
ids and 0.5 to 1.0 g/kg/day, 0.5 to 1.0 g/kg/day and 3.0 g/
kg/day of lipids, respectively.
Minimal enteral nutrition could be initiated within
the first 48 hours of life and the progression to exclusive-
ly enteral nutrition was performed according to the clini-
cal status of the child, with increments of 20 mL/kg/day
in volume. Human milk was only to be used where possi-
ble, and formula for preterm infants when breast milk was
not available. The use of additives to human milk started
when human milk volume reached 100 mL/kg/day.
The numerical variables were expressed as median
and range, and compared using the Mann-Whitney U test,
or the mean and standard deviation, compared using the
Student’s t test. The categorical variables were expressed
as numbers and percentages, and compared using the
chi-square or Fisher’s exact test.
To assess the factors associated with the percentage of
weight loss, time to regain birth weight and frequency of
small children for post-conceptual age, a logistic regres-
sion model was created using the variables with p value
<0.15. The statistical analysis was performed using Stata
10.0 software. Statistical significance was set at 5% (p <0.05).
R
esults
During the study period, 305 preterm infants with birth
weights between 500 and 1,499 g were admitted to the
NICU at Hospital São Paulo. One hundred and one of
these were excluded: 87 for death ≤7 days, 11 for major
congenital malformations and 3 for not using PN and
EN. Twenty medical records were not located, although
some of the data was available. The study group and the
group with incomplete information were similar accord-
ing to the perinatal variables, but the use of central ve-
nous catheter was higher (p = 0.001) in the group with
incomplete information (7
vs
. 37.5%).
The 184 newborns were divided into two subgroups
according to birth weight: group (G1) – 500 to 999 g
(n=63) and group (G2) – 1,000 to 1,499 g (n=121). Except
for gender, all clinical variables were different between
subgroups (Table 1).
The infusion of glucose began within the first hours
of life in all patients. PN was administered in 169 (92%)
newborns (63 in G1 and 106 in G2) and their character-
istics are shown in Table 2.
The number of children receiving amino acids with-
in the first 48 hours of life, between 48 and 72 hours and
after 72 hours were, respectively, 36 (57.2%), 14 (22.2%)
and 13 (20.6%) in G1, and 54 (50.9%), 31 (29.2%) and 21
(19.9%) in G2, while the ones receiving lipids in these pe-
riods were, respectively, 36 (57.2%), 14 (22.2%) and 13