Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1993-8-3
pubmed:abstractText
In about 10% of pregnancies overall, the fetus discharges meconium (its bowel contents) into the amniotic fluid during labour. In about 10% of cases where meconium is passed, the fetus gasps, inhaling the sticky meconium into the upper respiratory tract. After birth, the meconium blocks the air passages in the lungs, impairing gas exchange--meconium aspiration syndrome (MAS). Up to 20% of infants suffering from MAS die and recently published studies have shown a long-term effect of MAS in causing cough and wheeze. The risk of meconium aspiration is thought to be increased by intrauterine hypoxia. At present, meconium is only noticed at birth or occasionally when amniotic fluid leaks past the presenting part of the fetus. A method has been developed which measures absolute meconium concentration with a 99% prediction interval of +/- 30 g l-1; allows monitoring of the rate of appearance of meconium linearly with a nonlinearity of 5%, and differentiates between meconium and blood. The method uses the ratio of the intensity of back-scattered light from the amniotic fluid at 700 and 415 nm, the latter being near the peak of light absorption by meconium and the former a reference value. The ratio is also affected by the presence of blood. However, blood has specific absorption peaks at 540 and 575 nm from which it can be detected (the presence of blood is also a significant abnormality, and is relatively uncommon). The measurement method could easily be integrated into an optical sensor mounted onto an intrauterine probe.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0141-5425
pubmed:author
pubmed:issnType
Print
pubmed:volume
15
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
229-34
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
A method for continuous monitoring of meconium in the amniotic fluid during labour.
pubmed:affiliation
Biomedical Engineering Research Unit, Charing Cross & Westminster Medical School, Chelsea and Westminster Hospital, London, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't