[Efficacy of oral administration of a micellaar solution of vitamin K during the neonatal period]

Association between vitamin B12intake and EURRECA's prioritized biomarkers of vitamin B12in young populations: a systematic review

Objective

To review evidence on the associations between vitamin B12intake and its biomarkers, vitamin B12intake and its functional health outcomes, and vitamin B12biomarkers and functional health outcomes.

Design

A systematic review was conducted by searching electronic databases, until January 2012, using a standardized strategy developed in the EURRECA network. Relevant articles were screened and sorted based on title and abstract, then based on full text, and finally included if they met inclusion criteria. A total of sixteen articles were included in the review.

Setting

Articles covered four continents: America (n4), Europe (n8), Africa (n1) and Asia (n3).

Subjects

Population groups included healthy infants, children and adolescents, and pregnant and lactating women.

Results

From the total number of 5815 papers retrieved from the initial search, only sixteen were eligible according to the inclusion criteria: five for infants, five for children and adolescents, and six for pregnant and lactating women.

Conclusions

Only one main conclusion could be extracted from this scarce number of references: a positive association between vitamin B12intake and serum vitamin B12in the infant group. Other associations were not reported in the eligible papers or the results were not provided in a consistent manner. The low number of papers that could be included in our systematic review is probably due to the attention that is currently given to research on vitamin B12in elderly people. Our observations in the current systematic review justify the idea of performing well-designed studies on vitamin B12in young populations.

[Prophylactic vitamin K for vitamin K deficiency bleeding of the newborn]

BACKGROUND

The administration of vitamin K immediately after birth has shown a significant decrease in the incidence of newborn bleeding, but there is not enough evidence to determine the most appropriate method of administration. The objective of this review is to determine the effectiveness of orally administered vitamin K compared to the intramuscular route in the prevention of hemorrhagic disease of newborn (HDN).

METHODS

We conducted a systematic review of the main databases (Medline, Embase and Cochrane, among others) without limitation by date, language or type of study. Selected studies evaluated the efficacy and safety of vitamin K. Excluded were studies in pregnant women in preterm infants or patients with pathology. The validity of these studies was assessed by CASPe tools for systematic reviews and clinical trials.

RESULTS

Only two studies evaluated clinical aspects. They showed a reduction in the incidence of bleeding in the newborn after intramuscular prophylaxis with vitamin K. With regard to the oral route, different studies examined the effectiveness of vitamin K by determining biochemical parameters (factor X, prothrombin time and index, vitamin K1 in plasma and prothrombin antigen, among others) with inconclusive results regarding the route of administration and the number of doses.

CONCLUSIONS

There is sufficient evidence to support the effectiveness of a single intramuscular dose of vitamin K to prevent the classic form of HDN. With regard to late HDN and oral route, the results are inconclusive because the studies used biochemical indicators of effectiveness, which can not be correlated with the actual coagulation status of the newborn due to lack of scientific evidence.

Prophylactic vitamin K for vitamin K deficiency bleeding in neonates

BACKGROUND

Vitamin K deficiency can cause bleeding in an infant in the first weeks of life. This is known as Hemorrhagic Disease of the Newborn (HDN). HDN is divided into three categories: early, classic and late HDN. Early HDN occurs within 24 hours post partum and falls outside the scope of this review. Classic HDN occurs on days one to seven; common bleeding sites are gastrointestinal, cutaneous, nasal and from a circumcision. Late HDN occurs from week 2-12; the most common bleeding sites are intracranial, cutaneous, and gastrointestinal. Vitamin K is commonly given prophylactically after birth for the prevention of HDN, but the preferred route is uncertain.

OBJECTIVES

To review the evidence from randomized trials in order to determine the effectiveness of vitamin K prophylaxis in the prevention of classic and late HDN. Main questions are: Is one dose of vitamin K, given after birth, able to significantly reduce the incidence of classic and late HDN? Is there a significant difference between the oral route and the intramuscular route in preventing classic and late HDN? Are multiple oral doses of vitamin K, given after birth, able to significantly reduce the incidence of classic and late HDN?

SEARCH STRATEGY

The standard search strategy of the Cochrane Neonatal Review Group was used.

SELECTION CRITERIA

All trials using random or quasi-random patient allocation, in which methods of vitamin K prophylaxis in infants were compared to each other, placebo or no treatment, were included.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by each author and were analysed with the standard methods of the Cochrane Collaboration and its Neonatal Review Group, using relative risk, risk difference and weighted mean difference.

MAIN RESULTS

Two eligible randomized trials, each comparing a single dose of intramuscular vitamin K with placebo or nothing, assessed effect on clinical bleeding. One dose of vitamin K reduced clinical bleeding at 1-7 days, including bleeding after circumcision, and improved biochemical indices of coagulation status. Eleven additional eligible randomized trials compared either a single oral dose of vitamin K with placebo or nothing, a single oral with a single intramuscular dose of vitamin K, or three oral doses with a single intramuscular dose. None of these trials assessed clinical bleeding. Oral vitamin K improved biochemical indices of coagulation status at 1-7 days. There was no evidence of a difference between the oral and intramuscular route in effects on biochemical indices of coagulation status. A single oral compared with a single intramuscular dose resulted in lower plasma vitamin K levels at two weeks and one month, whereas a 3-dose oral schedule resulted in higher plasma vitamin K levels at two weeks and at two months than did a single intramuscular dose.

REVIEWER'S CONCLUSIONS

A single dose (1.0 mg) of intramuscular vitamin K after birth is effective in the prevention of classic HDN. Either intramuscular or oral (1.0 mg) vitamin K prophylaxis improves biochemical indices of coagulation status at 1-7 days. Neither intramuscular nor oral vitamin K has been tested in randomized trials with respect to effect on late HDN. Oral vitamin K, either single or multiple dose, has not been tested in randomized trials for its effect on either classic or late HDN.