Page 127 - Critical Maternity & Newborn Health Nursing

Ruptured Vasa Previa

In velamentous insertion of the cord, some of the fetal vessels in the

membranes cross the region of the internal os. When the membranes

ruptures, the fetal vessels are torn and bleeding occurs which is usually

slight. Fetal heart rate abnormalities are detected

Fig (14):Ruptured Vasa Previa

Adopted from

https://www.researchgate.net/publication/278044303/figure/download/fig2/AS:601706597449729@1520469
440560/A-ruptured-vasa-previa-traversing-the-fetal-membrane-of-the-lower-segment-over-the.png

Investigations:

The fetal blood can be detected by:

• A pt's test: 4-6 drops of the antepartum hemorrhage blood is added

to 10 ml of water then 2 ml of sodium hydroxide is added. The fetal

blood remains red/ pink for at least 2 minutes and turns green/brown

after 10-20 minutes due to resistance to alkali in formation of

alkaline hematin. If the blood is maternal m origin it turns

green/brown within 10 seconds.

• Spectrophotometer. Fetal hemoglobin shows different ultraviolet

absorption than adult hemoglobin.

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