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The Purpose of this Information This information is being provided to you in order to prepare you to make decisions about your own health care. If you should ultimately decide that surgery is the best treatment option for you, this section will help you understand what happens during a ruptured cerebral aneurysm and will help you prepare for your role in the healing and recovery process. Read it thoroughly and answer the questions before making your final decision about your treatment options. The Health Care Team's Role The duty of your health care team is to:
The Patient's Resposibilities You are the only one who can decide to have surgery. It is important that you take ownership of this decision, recognizing the limitations your particular physical condition places on the potential success of each of the treatment options. If you choose to have surgery, your physical condition and your mental attitude will determine your body's ability to heal. You must approach your surgery with confidence, a positive attitude, and a thorough understanding of the anticipated outcome. You should have realistic goals - and work steadily to achieve those goals. The decision to have or not to have surgery includes weighing the risks and benefits involved. You will make the final decision, so ask questions about anything you do not understand. Since medical care is tailored to each person's needs and differences, not all information presented here will apply to the patient's treatment or its outcome. Seek the advice of your physician and other members of the health care team for specific information about the patient's medical condition. Table Of Contents
The human brain is well protected from injury. It is firmly surrounded by three layers of membranes, encased in a rigid skull (the cranium), and covered by a muscular scalp (Fig. 1A). Each of these barriers to the brain is important, because brain tissue is fragile and unforgiving if injured.  Three membrane layers, the meninges, protect the brain from injury and infection (Fig. 2). The dura mater, tough and fibrous, lines the skull. The thinner pia mater, highly vascular (containing many blood vessels), covers the brain's surface. Between these two is another, the arachnoid.  The brain floats in a protective cushion of cerebrospinal fluid (CSF), which flows within the subarachnoid space - beneath the arachnoid membrane, on top of the pia mater. It also surrounds the spinal cord and fills open spaces (ventricles) inside the brain. The amount of CSF that circulates around the brain normally stays the same, replenished by the body 5 or 6 times each day, and helps to maintain a constant pressure inside the skull, known as intracranial pressure (ICP). The largest part of the brain is divided into two major areas, the left and right cerebral hemispheres, which control most of the body's thought and sensory processes. Some sections of each hemisphere can be "mapped" to correspond with the body functions for which they seem to be responsible: vision, speech, hearing, personality, memory, movement, touch, smell, and taste (Fig. 1B, above). The brain stem controls such vital automatic functions as breathing, heartbeat, and eye movement. It anchors the brain to the other part of the central nervous system, the spinal cord, and acts as the main circuit for all brain activity. Twelve pairs of cranial nerves, emerging from the base of the brain and the brain stem, transmit nerve impulses for vision, hearing, smell, and many other important body functions. Subarachnoid Hemorrhage What is it? Hemorrhage is the medical term for bleeding. The rupture of one of the brain's blood vessels can cause bleeding into the subarachnoid space - beneath the arachnoid membrane, on top of the pia mater - and into brain tissue. The bleeding usually stops, at least temporarily, when a clot forms over the ruptured area. Why does it happen? The most frequent cause of spontaneous subarachnoid hemorrhage (not due to injury) is the rupture of a small aneurysm, or bulging sac, on one of the blood vessels that supplies the brain (Fig. 3). It is usually impossible to determine why the aneurysm forms and bursts, but the condition is common in adults and may be associated with aging, diabetes, pregnancy, hypertension (high blood pressure), heredity, or trauma.  Cerebral aneurysms are usually of three types: saccular with a narrow "neck" (called "berry" aneurysms because of their shape and their tendency to occur in clusters); saccular with a broad base; and fusiform, in which a short section of the artery bulges all the way around (Fig. 4). Each shape determines the degree of difficulty a surgeon faces in attempting to treat the problem.  An aneurysm ruptures spontaneously - even during sleep - and therefore is not related to the strain of hard work, sexual intercourse, or other physical activity. Although it is not always possible to discover the exact source of bleeding, other causes of spontaneous subarachnoid hemorrhage include: arteriovenous malformations, small angiomas, certain types of infections, and bleeding disorders. What symptoms can it cause? A ruptured cerebral aneurysm at first causes severe headache, which can be followed by nausea, vomiting, double vision or sensitivity to light, neck pain or stiffness, weakness, memory loss, paralysis, coma, or death. How severe the symptoms are and how long they last will depend on the amount and location of the bleeding. Blood in and around the brain can cause pressure, swelling, and brain irritation, which can lead to drowsiness, confusion, weakness or paralysis, memory loss, speech problems, behavior changes, or coma (complete loss of consciousness). What complications can occur? The blood vessels around the aneurysm are irritated by the blood from the hemorrhage and will at times go into a state of spasm, tightening and narrowing (Fig. 5). This vasospasm ("vaso" meaning vessel) can occur any time after the rupture until the hemorrhaged blood has been absorbed by the body, and it can increase any or all symptoms. It is the body's own attempt to prevent a second hemorrhage by restricting the flow of blood through the vessels around the aneurysm. Vasospasm thus reduces pressure on the delicate aneurysm but unfortunately also reduces the normal blood supply to parts of the brain. 
Ongoing research is being done to discover a medicine that will control vasospasm; as yet, none has proven effective. Other complications from subarachnoid hemorrhage, such as hydrocephalus, hematoma (blood clot), and brain swelling, involve the brain; but other body systems can also be affected because of the severe nature of the illness. Pulmonary embolus, heart abnormalities, and bleeding from an ulcer may cause further complications. How is it diagnosed? Several tests are used to confirm the diagnosis of ruptured cerebral aneurysm. Some are explained in the latter portion of this section. Because cerebrospinal fluid flows within the subarachnoid space, a sample of CSF taken during a spinal tap at the base of the spine will show blood from the hemorrhage. A CT scan will show blood inside the skull and indicate how much bleeding has occurred. To find the source of the hemorrhage, an angiogram is performed, which may have to be repeated to try to pinpoint the aneurysm's exact location. Activity Because the aneurysm can rupture again, a quiet, restful atmosphere is important. The patient usually is placed in the Intensive Care Unit (ICU), a highly specialized area providing close observation with specialized nursing care. Complete bedrest without physical strain is essential while the patient's condition stabilizes - usually in preparation for surgery. Medications Medications will be given when necessary to reduce pain, control blood pressure, relieve stress, and maintain fluid balance. Breathing If necessary, a respirator may be used to help the patient breathe and to control intracranial pressure. Most often, however, oxygen is merely administered to the patient through nasal prongs or a mask. Monitoring devices Various monitoring devices may be used to assess the patient's condition during recuperation. Among the most common are: an EKG (heart) monitor, an ICP monitoring device, a Swan-Ganz catheter to assess the patient's fluid balance, and an arterial line to continuously measure blood pressure and aid in drawing frequent blood samples for laboratory study. Nutrition Intravenous (I.V.) fluids may be given until liquids and food can be taken adequately by mouth. The amount of fluid given will be closely monitored until the dangers of brain swelling (edema) and vasospasm lessen. Surgery for Ruptured Cerebral Aneurysm When is surgery performed? Surgery is performed only when the patient's condition allows, and only when it can correct one or more problems caused by the illness. It is done primarily to relieve pressure on the brain from a large blood clot, or to place a clip around the "neck" of the aneurysm in an attempt to prevent a second rupture. Unfortunately, surgery may be delayed when vasospasm is present, because manipulation of the already irritated blood vessels and brain tissues may worsen the patient's condition. Surgery also cannot reverse brain injury already caused by the hemorrhage, which must be treated with rest and rehabilitation. How might surgery be especially complicated? As already mentioned, the shape of an aneurysm can cause problems of its own. Berry aneurysms with narrow "necks" are easiest for the surgeon to place the tiny metal clip around. The broad base of the saccular type may be impossible to clip; and, of course, clipping the fusiform aneurysm cannot be done without sacrificing the flow of blood through the artery. Unfortunately, shape is not the only complicating factor once the aneurysm is reached (Fig. 6). It may be impossible for a surgeon to clip an especially large aneurysm or one with scar tissue around it. The scar tissue may prevent the neck of the sac from being freed for clipping, or it may attach the aneurysm to a vital structure in the brain that cannot be touched without devastating consequences (such as the optic nerve, the hypothalamus, the pons, or a major artery). In such cases, either surgery is impossible or an attempt is made to treat the aneurysm in another way (such as coating it with a plastic substance).  What happens afterwards? Successful recovery from surgery for ruptured cerebral aneurysm requires that the patient and his family approach the operation and recovery period with confidence based on a thorough understanding of the process. The surgeon has the training and expertise to clip the aneurysm, if possible, and remove the blood clot; however, recovery may at times be limited by the extent of damage already caused by the hemorrhage and by the brain's ability to heal. If a neurologic deficit remains, a period of rehabilitation will be necessary to maximize improvement. This process requires that the patient and his family maintain a strong, positive attitude, set small goals for improvement, and work steadily to accomplish each goal. Figure 7 shows where surgery for most cerebral aneurysms takes place - deep inside the brain, between its lobes and near vital arteries and nerves.  After a general anesthetic has been given, the patient is positioned according to the area of the brain that must be reached. Usually, the operation is performed with the patient lying on his or her back. The hair over the incision area is then clipped and shaved. The patient's blood pressure may be lowered with medication to allow the operation to proceed with less risk of re-bleeding.
Next, a small burr hole is drilled in the skull with a power drill (Fig. 9). A surgical saw is used to connect the holes and create a "window" in the skull through which surgery will take place (Fig. 10). The removed bone piece is kept sterile for replacement at the end of the operation.  Exposure of the brain The exposed dura is cut with a scalpel or scissors and is laid back to uncover the brain. A surgical microscope is used as the procedure is continued. Identifying and clipping the aneurysm The brain's lobes are gently retracted (pulled back) until the location of the aneurysm is reached, using the surgical microscope and microsurgical instruments (Fig. 11).  The tissue-paper-thin aneurysm is carefully freed from the scar tissue surrounding it, and its junction with the brain's blood vessels is identified (Fig.12). One of various kinds of clips is placed across the base of the aneurysm and is adjusted until its position is accurate (Fig. 13A). This allows the aneurysm to collapse as shown in (Figure 13B), but spares the essential blood vessels around it.  
At times the aneurysm will rupture again while surgery is taking place. The surgeon then carefully tries to control the hemorrhage while continuing the delicate clipping procedure. Replacement of bone After the dura has been stitched closed, the piece of bone is replaced, using wires made of surgical steel (which will remain in place permanently). An intracranial pressure (ICP) monitoring device may then be implanted.
Risk Certain risks must be considered with any surgery. Although every precaution will be taken to avoid complications, among the most common risks possible with surgery are infection, excessive bleeding (hemorrhage), and an adverse reaction to anesthesia. Surgery for ruptured aneurysm is a life-saving attempt involving an already-injured brain. Possible consequences include: further hemorrhage from the aneurysm, vasospasm, paralysis, coma, and death. Clinical experience and scientific calculation indicate that, in general, surgical risks are limited; however, surgery remains a human effort. Unforeseen circumstances can complicate any surgical procedure and lead to serious or even life-threatening situations. Although such complications are rare, the patient and his family should feel free to discuss the question of risk with the physician, or with his representative during times of emergency. Observation The patient will be transferred from the recovery room after surgery to the intensive care unit (ICU), where his condition can be closely monitored. lntracranial pressure may be continuously measured during recuperation. When fully conscious and stable, the patient will be returned to his regular room. Pain A dull headache is usually all the post-operative pain to be expected. Pain medication will be ordered for generalized discomfort. Incision care The incision will be covered with a turban-like dressing. When this dressing is removed, some other head covering may be used. The skin sutures usually are removed within five to seven days. Nutrition Intravenous (I.V.) fluids will be ordered during the early recovery period and continued until liquids may be taken adequately by mouth. For the first few days, all fluids taken will be carefully monitored. As the danger of brain swelling lessens, more fluids may be taken. When there is no nausea or vomiting, and the patient is fully awake, both liquids and diet may be increased. Emotional changes It is normal to feel discouraged and tired for several days after surgery. These feelings may be the body's natural reaction to the cutback of extra hormones it put out to handle the stress of surgery. Although emotional let-down is not uncommon, it must not be allowed to get in the way of the positive attitude essential to recovery and the return to normal activity. Discharge from the hospital The time spent in the hospital may be different for each patient. Discharge will be planned when the patient's recovery can be handled at home or in an alternate facility. Home Recovery The home recovery program will be individualized for each patient. It will depend largely on the extent of brain injury caused by the subarachnoid hemorrhage, the patient's ability for self-care, and the progress of his recovery. Fever, a severe headache, or any swelling or drainage around the incision should be reported to the physician immediately. During home recovery, changes in the patient's speech, movement, mental ability, level of consciousness, or memory may be noticed. These should be discussed with the physician during post-operative visits. Speech, occupational, or physical therapies may then be recommended. Healing is the body's natural process of restoring its damaged tissues to a normal or nearly normal state. Although healing may be improved by general good health, proper nutrition, rest, and physical fitness, it will occur without one's having to work at it. Recovery is the process during which one works to become well. It requires a gradual but persistent effort to increase physical strengths and minimize weaknesses. One must concentrate on improvement, not on what symptoms remain. This focus on progress, combined with the constant effort to improve, maintains the positive attitude that will speed the return to normal daily activity. Evaluation of Ruptured Cerebral Aneurysm CT Scan The CT scan (sometimes called CAT scan) is a computerized test that rapidly x-rays the body in cross-sections, or slices, as it is moved through a large, circular machine. The initials, CT stand for "Computerized Tomography," tomo- meaning section, and -graph meaning record, or picture. The x-rays are pieced together by the computer to form a picture of the head, which can show hemorrhages, swelling, tumors, and other brain abnormalities. Cerebral angiogram The cerebral angiogram (also called arteriogram) is a contrast x-ray study done to visualize the blood vessels of the brain. The name is derived from cerebrum (the largest part of the brain), angio- (blood vessels), and -gram (record, or picture). A dye, known as a contrast medium, is injected into an artery in the thigh or arm. X-rays are taken while it flows with the blood through the circulatory system of the brain. The dye outline can show aneurysms, hemorrhages, tumors, and other brain abnormalities. Spinal tap This test is used to detect blood in the cerebrospinal fluid (CSF) that surrounds the brain and spinal cord, which can indicate bleeding into the subarachnoid space of the brain. A sample of CSF is "tapped" from an area just below the end of the spinal cord, through a thin needle, inserted into the spinal canal in the lower back.
Test your knowledge of ruptured cerebral aneurysm by answering the following questions.
Aneurysm - a bulging sac located on a blood vessel, caused by a weakening of its wall Arachnoid - middle of three membranes surrounding the brain Artery - blood vessel that carries blood away from the heart Brain Stem - area directly above and attached to the spinal cord; the main circuit for all brain activity Cerebral - derived from cerebrum, meaning the largest portion of the brain Cerebral Angiogram - a contrast x-ray during which injected dye is used to show possible brain abnormalities Cerebral Hemispheres - the two largest sections of the brain Cerebrospinal Fluid (CSF) - protective fluid found in the spinal column and between the two innermost membranes around the brain Cranium - the rigid skull that forms a closed "box" around all brain tissue CT Scan (CAT Scan) - computerized test that x-rays the body in cross-sections Dura Mater - outermost of three membranes protecting the brain Fusiform Aneurysm - short, uniform bulge around a blood vessel Hemorrhage - medical term for bleeding ICP Monitor - a device surgically placed in the skull, used to measure pressure on the brain Meninges - three protective membrane layers surrounding the brain Pia Mater - the highly vascular membrane nearest the brain Rupture - breaking or bursting of tissue Saccular Aneurysm - bulge of a blood vessel, with either a narrow "neck" or a broad base Spinal Tap - a procedure during which cerebrospinal fluid (CSF) is withdrawn through a needle inserted in the spinal column Vasospasm - tightening and narrowing of a blood vessel
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