Besides that extrinsic vasoconstriction, the erythrocytes degradation products like; bilirubin and oxyhemoglobin lead to neuroinflammation that in turn increases the production of reactive oxygen species (ROS) which increases and decreases the production of endothelin 1 and endothelial NOS, respectively, the issue that yields in intrinsic vasoconstriction of the neighboring blood vessels and results in cerebral ischemia if left untreated.The use of calcium channel blockers, thought to be able to prevent the spasm of blood vessels by preventing calcium from entering smooth muscle cells, has been proposed for prevention. The calcium channel blocker nimodipine when taken by mouth improves outcome if given between the fourth and twenty-first day after the bleeding, even if it does not reduce the amount of vasospasm detected on angiography. It is the only Food and Drug Administration (FDA)-approved drug for treating cerebral vasospasm. In traumatic subarachnoid hemorrhage, nimodipine does not affect long-term outcome, and is not recommended. Other calcium channel blockers and magnesium sulfate have been studied, but are not presently recommended; neither is there any evidence that shows benefit if nimodipine is given intravenously.Nimodipine is readily authorized in the form of tablets and solution for infusion for the prevention and treatment of complications due to vasospasm following subarachnoid hemorrhage. Another sustained formulation of nimodipine administered via an external ventricular drain (EVD), called EG-1962, is also available. In contrast to the tablets and solution formulations of Nimodipine which require an administration every 4hrs for a total of 21 days, the sustained formulation, EG-1962, needs to be administered once directly into the ventricles.
Placental abruption is when the placenta separates early from the uterus, in other words separates before childbirth. It occurs most commonly around 25 weeks of pregnancy. Symptoms may include vaginal bleeding, lower abdominal pain, and dangerously low blood pressure. Complications for the mother can include disseminated intravascular coagulopathy and kidney failure. Complications for the baby can include fetal distress, low birthweight, preterm delivery, and stillbirth.The cause of placental abruption is not entirely clear. Risk factors include smoking, pre-eclampsia, prior abruption (most important and predictive risk factor), trauma during pregnancy, cocaine use, and previous cesarean section. Diagnosis is based on symptoms and supported by ultrasound. It is classified as a complication of pregnancy.For small abruption, bed rest may be recommended, while for more significant abruptions or those that occur near term, delivery may be recommended. If everything is stable, vaginal delivery may be tried, otherwise cesarean section is recommended. In those less than 36 weeks pregnant, corticosteroids may be given to speed development of the babys lungs. Treatment may require blood transfusion or emergency hysterectomy.Placental abruption occurs in about 1 in 200 pregnancies. Along with placenta previa and uterine rupture it is one of the most common causes of vaginal bleeding in the later part of pregnancy. Placental abruption is the reason for about 15% of infant deaths around the time of birth. The condition was described at least as early as 1664. Signs and symptoms
In the early stages of placental abruption, there may be no symptoms. When symptoms develop, they tend to develop suddenly.