Vasa praevia
| Vasa praevia | |
 | |
|---|---|
| Vasa praevia | |
| ICD-10 | O69.4 |
| ICD-9 | 663.5 |
| DiseasesDB | 13743 |
| eMedicine | med/3276 |
Vasa praevia (vasa previa AE) is an obstetric complication defined as "fetal vessels crossing or running in close proximity to the inner cervical os. These vessels course within the membranes (unsupported by the umbilical cord or placental tissue) and are at risk of rupture when the supporting membranes rupture."[1]
Etiology & Pathogenesis
Vasa previa is present when fetal vessels traverse the fetal membranes over the internal cervical os. These vessels may be from either a velamentous insertion of the umbilical cord or may be joining an accessory (succenturiate) placental lobe to the main disk of the placenta. If these fetal vessels rupture the bleeding is from the fetoplacental circulation, and fetal exsanguination will rapidly occur, leading to fetal death.
Risk Factors
Vasa previa is seen more commonly with velamentous insertion of the umbilical cord, accessory placental lobes, and multiple gestation.
Diagnosis
- This is rarely confirmed before delivery but may be suspected when antenatal sono-gram with color-flow Doppler reveals a vessel crossing the membranes over the internal cervical os.[2][3]
- The diagnosis is usually confirmed after delivery on examination of the placenta and fetal membranes.
- Most often the foetus is already dead when the diagnosis is made; because the blood loss (say 300ml) constitutes a major bulk of blood volume of the foetus (80-100ml/kg i.e. 300ml approx for a 3kg foetus).
Treatment
Treatment immediately with an emergency cesarean delivery is usually indicated.[4][5]
See also
References
- ↑ Yasmine Derbala, MD; Frantisek Grochal, MD; Philippe Jeanty, MD, PhD (2007). "Vasa previa". Journal of Prenatal Medicine 2007. 1 (1): 2–13.Full text
- ↑ Lijoi A, Brady J. "Vasa previa diagnosis and management". J Am Board Fam Pract. 16 (6): 543–8. PMID 14963081.Full text
- ↑ Lee W, Lee V, Kirk J, Sloan C, Smith R, Comstock C (2000). "Vasa previa: prenatal diagnosis, natural evolution, and clinical outcome". Obstet Gynecol. 95 (4): 572–6. doi:10.1016/S0029-7844(99)00600-6. PMID 10725492.
- ↑ Bhide A, Thilaganathan B (2004). "Recent advances in the management of placenta previa". Curr Opin Obstet Gynecol. 16 (6): 447–51. doi:10.1097/00001703-200412000-00002. PMID 15534438.
- ↑ Oyelese Y, Smulian J (2006). "Placenta previa, placenta accreta, and vasa previa". Obstet Gynecol. 107 (4): 927–41. PMID 16582134.