Critical Appraisal

 
Critical Appraisal
Introduction
This study is based on preterm infants that are born within 37 weeks of gestational age. These infants contain very low iron capacity. During their postnatal period there might be deficiency of iron if it is not expanded from birth. The standard measure is to supply iron in these infants during the time of 6 to 8 weeks of age. (John & Mark, 2012) During this period, supplementation of iron is unnecessary as no active erythropoiesis is present. As this erythropoiesis is build up, the insufficient iron stores might get exhausted. This is normally followed by decline in the tissue iron that could lead to biochemical defects such as collagen and synthesis of DNA. A matured preterm brain is susceptible to effects of iron shortage. The iron shortage might also affect the functioning of organ systems such as Heart and skeletal muscle. (Williams, 1975) The previous studies conducted on early iron supplementation produce differing results. This study is designed on random basis to evaluate whether 14 days of life in VLBW can enhance their iron stores at the age of 60 days.
Study Design
This research was conducted from May 2006 till November 2006 at neonatal unit in India. The preterm infants weighing less than 1500 g and qualified minimum 100 mL/kg/day oral feeds within 14 days were entitled for participation in the study. (Edmond, 2006) Infants
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containing anomalies disease were not included. The enrollment process includes written consent made from the parents. The approval of study was made from ethics committee of the institution.
Research Methodology
Randomized Controlled Trials
The enrolled neonates were allocated randomly to control group or early iron on fourteen day life using random computer generated sequence numbers. The laboratory personnel were wearing masks for treatment purpose. The infants were started on oral iron in dosage of 4mg/kg/day for births weighing less than 1000 g or 3 mg/kg/day for births weighing between 1000-1500 g. (Friel & Andrews, 2005)
The daily mixture of iron was maintained using normal preparation of colloidal iron carrying 25 mg of elemental iron/ mL. This preparation contains the mixture of vitamin B12 (5 μg / mL) and folic acid (200 μg / mL). (Gallagher, 1995)The first three doses of iron were monitored and then parents were asked to manage the daily dose requirements. Datasheets were provided to them for marking of daily dose. During the study process, the infants allotted to control groups did not receive iron supplements. Infants of both Groups were feed with EBM (expressed breast milk) until the formula feeds start. An infant that feeds EBM with greater than fifty percent daily uptake were supplemented with human milk that contains minerals & vitamins excluding iron. For Infants feed on specified formula, the iron dose was corrected to cope with required daily dose. The preterm formula contains 13.6 mg/l of iron and provides nearly 2 mg/ kg of elemental iron at daily intake of 150 ml/kg. Those infants feed on specified formula but in
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the control group, the expected iron was identified and recorded separately. The guideline over restricted red cell transfusion was adopted in both groups.
Outcome variables
Primary variable include serum ferritin, while secondary variables include anthropometric and haematologic parameters set at sixty days. The outcomes demanded for neonatal morbidities include CLD, PVL, NEC and ROP. CLD requires oxygen till 28 days during postnatal age. ROP was managed and diagnosed according to standard guidelines of (9, 10).
Re Hospitalization was considered to be the time period of more than 1 day after first discharge from hospital. All the basic characteristics of registered infants such as age, sex and iron supplementation were recorded in a format. During the initial hospitalization, other details such as blood loss, blood transfusion including the mode of feeding was recorded.
All the infants were daily monitored until the study period. Weight, length, requirement for blood transfusion and chances of significant morbidities were recorded during visits. Haemoglobin, haematocrit and Ferritin were identified during enrolment and at sixty days of age. (Miles, 1974) Serum Ferritin was projected by enzyme with the help of kit with high variations. (Minimum concentration was 1 μg/l) and low assay variations were 5.4% and 5.7%. It was probable that ferritin level will get affected by inflammation/ infection, so blood samples in infants were delayed with active infection. The samples of two infants were taken when the C reactive protein become negative, which results in the delay of two or three days after enrolment. Haemoglobin and Haematocrit were predicted using Coulter LH Analyzer.
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Results
Out of 50 infants, 46 were enrolled and 4 were rejected from the study period. Out of 46 infants 24 were randomized to control group and 22 to early iron. Results were available for 42 infants, 2 samples got Ha