Question

Ms. Jones is a 45-year-old patient who had a clipping of an aneurysm 5 days ago. At present, she is receiving mechanical ventilation and has a pulmonary artery catheter, arterial line, and ventriculostomy in place. Cerebral angiography performed today indicates that she is experiencing cerebral vasospasm. To reverse or overcome the vasospasm, she is started on oral nimodipine. Other treatments include fluid administration (hypervolemia) and medications to increase the blood pressure (hyptertension). Questions 1. When is a patient at greatest risk for developing vasospasm? 2. What effects does vasospasm have on cerebral function? 3. Discuss the benefits of administering nimodipine, and achieving hypervolemia and hypertension? 4. Explain the purpose of a ventriculostomy in this patient

Answer 1

1. Vasospasm is the spasm of the vessels that occur due to vasoconstriction, ischemia, and necrosis of the tissue. Cerebral vasospasm occurs as a result of subarachnoid hemorrhage. The patient is having a history of atherosclerosis which increases the risk of cerebral vasospasm.

2. Vasospasm results in the narrowing of arteries in the brain which takes place adjacent to the area of subarachnoid hemorrhage. Narrowing of arteries leads to poor flow of blood which results in ischemia and necrosis of brain tissue.

3. Nimodipine is the calcium channel blocker that used to treat the vasospasm in stroke patients. It influxes the calcium in the smooth muscle cell and inhibit the vasoconstriction. It increases the cerebral perfusion pressure thereby increasing the blood pressure (hypertensive). The augment of blood flow increases the blood volume (hypervolemia). Nimodipine used in the combination of hypertensive and hypervolemic therapy.

4. Ventriculostomy is a catheter placed in the fluid-filled spaces of the ventricles in the brain. It drains the cerebrospinal fluid and the waste products of blood that comes out as a result of vasospasm. It maintains the intracranial pressure.