Early help for hydrocephalus is a chance for a normal life. Professional management of the disease and competent rehabilitation can reduce complications and the degree of disability by 60%.
What it is
The Greek word “hydrocephalus” is used by specialists along with the Russian term “dropsy of the brain.” If translated literally from ancient Greek. ὕδωρ “water” + κεφαλή “head”, so it turns out – “water in the head”.
However, we are not talking about water, but about cerebrospinal fluid (CSF), which accumulates in the ventricles of the brain and/or in the space between the membranes of the brain. Liquor is produced in the ventricles, then circulates inside the skull, then moves into the circulatory system through special veins. This is a kind of “safety cushion”. It protects the brain and spinal cord from external mechanical influences, that is, it softens blows and other sharp impacts. It also removes harmful substances from the brain and delivers useful ones, that is, it supports metabolic processes between the blood and the brain.
Usually there is very little cerebrospinal fluid, in infants - only 50 ml. But if suddenly the production of cerebrospinal fluid becomes excessive or the outflow becomes difficult, an excess of it appears and intracranial pressure increases. This syndrome is called hydrocephalus.
Excess cerebrospinal fluid puts pressure on the brain - and this can lead to severe neurological disorders, decreased vision, weakness in the upper and lower extremities, decreased intellectual abilities, and most importantly, death.
Ventricular bypass surgery
First, let's talk about a disease such as hydrocephalus.
Hydrocephalus is a pathological condition accompanied by excessive accumulation of cerebral fluid (CSF) in the ventricles of the brain, caused by an imbalance between the production of cerebrospinal fluid and its absorption.
The causes of the occurrence and development of hydrocephalus in adults include:
- Brain tumors causing occlusion in various segments of the cerebrospinal fluid circulation system;
- Consequences of neuroinfection in the form of adhesive arachnoiditis or pachymeningitis;
- Previous subarachnoid hemorrhage of traumatic or vascular origin;
- Acute or chronic circulatory failure and cerebral ischemia, due to atherosclerotic lesions of cerebral vessels and other cerebrovascular diseases.
Separately, normal pressure hydrocephalus is distinguished, accompanied by expansion of the ventricular system against the background of normal pressure.
The clinical picture of normal pressure hydrocephalus consists mainly of three main symptoms, called by the authors the Hakim-Adams triad:
- Dementia in the form of a decrease in the level of wakefulness, fatigue, disorientation, development of severe intellectual impairment;
- Gait disturbance, which is manifested by uncertainty when walking, a “shuffling” gait, apraxia of walking, the development of lower spastic paraparesis with pathological foot signs;
- Urinary incontinence in the form of urgency and episodes of urinary incontinence.
Diagnosis of hydrocephalus is complex and consists of the following main components:
- Clinical examination by a specialist.
- CT and/or MRI of the brain.
- Examination by a neuro-ophthalmologist.
- Lumbar puncture (unloading test).
Shunting for hydrocephalus
Bypass surgery is effective in more than 85% of cases. The principle of the operation is to remove the “excess” volume of cerebrospinal fluid from the ventricular system using a system of tubes and a valve into the natural cavities of the human body (for example, ventriculo-peritoneal shunting - into the abdominal cavity or ventriculo-atrial shunting - into the right atrium).
Purpose of bypass:
Shunting is used for hydrocephalus (water on the brain) to reduce intracranial pressure and restore normal circulation of cerebrospinal fluid.
During the operation, a shunt system (a thin silicone tube and a small valve) is installed under the skin from the head to the neck or to the abdomen, which allows excess fluid accumulated in the ventricles of the brain to be removed into other cavities of the body: into the abdominal cavity (ventriculo-peritoneal shunt) or into blood circulation (ventriculoatrial shunt).
Impaired
circulation of cerebrospinal fluid : features
Impaired circulation of cerebrospinal fluid can occur in different patients and for various reasons. Symptoms of the disorder depend on the cause of the disorder. If, for example, the cause of the disorder is a tumor, then the tumor is often removed, as a result of which the hydrocephalus disappears (without shunting).
Common causes that lead to disruption of the normal circulation of cerebrospinal fluid and require shunting are the consequences of hemorrhage and brain injury. The most common indication for cerebral shunting is normal pressure hydrocephalus (NPH), the cause of which is unknown. This disease usually causes gait disturbances, and may also cause cognitive decline and urinary incontinence. In patients over 60 years of age, IGT develops slowly and this disease can only be treated with bypass surgery. Unfortunately, a clear diagnosis of IGT cannot be established before bypass surgery, so some patients may not receive the desired result from bypass treatment.
Methodology
performed
by a neurosurgeon who decides what type of shunt will be installed (ventriculo-peritoneal or ventriculo-atrial). The operation is performed under general anesthesia and usually lasts less than an hour. Typically two or three small incisions are made in the head and neck or abdomen through which the shunt is inserted. The shunt is a foreign body, so before surgery it is necessary to cure all existing inflammations and infections. When you arrive for surgery, your skin should be clean and undamaged. Also, before surgery, you need to check the condition of the oral cavity and teeth. This so-called “preventative examination” reduces the risk of bacterial infections of the shunt.
Postoperative pain at the incision site usually resolves with the use of pain medications. Hospitalization lasts from 3 to 5 days.
Consequences
of the intervention
Positive effects from the installation of a shunt can be observed immediately after the operation, and sometimes the positive effect of the operation can be noticed only after a few weeks. At a follow-up appointment with a neurosurgeon (approximately 2 months) after surgery, the treatment outcome is assessed. Almost without exception, the shunt remains in the patient's body for life and the patient's quality of life is significantly improved after shunting.
Various defects (shunt malfunctions) can occur in the shunt, such as blockage, inflammation, or overworking of the shunt. In such cases, it is necessary to correct the shunt. In certain cases, instead of shunt surgery, we can perform endoscopic ventriculocisternostomy of the bottom of the third ventricle.
Dr. BOSTI recommends the unique self-regulating valve from POLARIS.
Why is the valve needed?
The valves are used to treat hydrocephalus of the brain in children and adults. The valves help regulate the flow of cerebrospinal fluid from the ventricles of the brain to the site of absorption. The devices allow you to change operating pressure/flow settings without the need for revision operations.
The Polaris® Adjustable Valve is a precision ball-in-cone valve with a self-locking magnetic rotor. Valve adjustment is performed percutaneously using an adjustment kit specifically designed for this purpose. Each Polaris® valve model is adjustable to 5 pressure levels. The operating mode of the standard valve model is 30 - 200 mm H2O. To meet more rare clinical needs, valves with additional operating modes are used: 10-140 mm H2O, 50-300 mm H2O and 80-400 mm H2O. Each valve is individually tested during production and marked with a unique serial number.
Cause
Neurosurgeons count more than 180 reasons that can cause the development of hydrocephalus. It can be congenital (when a child is born with an excess amount of cerebrospinal fluid in the head) or acquired as a result of other problems:
– traumatic (develops after a trauma, for example, birth trauma, cerebral hemorrhage), – inflammatory (develops after neuroinfections), – tumor (the tumor blocks the outflow of cerebrospinal fluid or stimulates increased production), – vascular (due to vascular diseases of the brain), – idiopathic (when the reason is not clear).
At risk are premature babies and children with excised spina bifida (since the spinal cord is connected to the brain, hydrocephalus often manifests itself as a concomitant disease). Most often, hydrocephalus is detected before the age of three months; boys develop it more often than girls.
Causes and mechanism of development
Any pathology of the central nervous system can lead to a complication - hydrocephalus. Causes:
- inflammatory process in the brain;
- infectious diseases of the brain and its membranes (meningitis, encephalitis);
- head injuries;
- brain tumor;
- intracranial birth injury;
- pathological vascular changes;
- intoxication;
- circulatory disorders in the brain;
- alcoholism;
- chronic hypoxic condition;
- congenital anomaly.
Alenka. Reset stigmas
Svetlana Lisunova, an activist of the MBOO helping children with neurosurgical diseases “He needs you”, Alenka’s mother with post-hemorrhagic occlusive hydrocephalus, says:
“I stood under the door of the intensive care unit and only heard: “This is already a corpse. Why are you clinging to her”, “Imagine that it’s an abortion”, “It’s better to cry once now than to cry all your life later”
Difficult birth. Brain hemorrhage. They immediately said about their daughter: “she won’t survive.” And that’s probably why they didn’t do much about it. She lay in intensive care for 12 hours without artificial ventilation. She just lay there and gasped.
“Sick leave? If he dies, come and get sick leave.” They weren’t allowed to baptize: “There’s no point in shaking dirty robes here.” They didn’t take expressed milk: “We don’t need your goat urine here.”
At three months, Alenka, without waiting for her death, was nevertheless discharged home. Within a week, Svetlana realized that hydrocephalus was growing. Alenka cried sharply, burped heavily, her eyes literally popped out of her head - she was probably tormented by severe headaches. The accumulating cerebrospinal fluid began to put pressure on the brain.
Svetlana is a doctor by training. She could recognize hydrocephalus. What's next? Of course, she, an orthopedist by specialty, took a course in neurosurgery in a very truncated form. But what exactly? I got out the textbooks. “A condition incompatible with life... die in the first days of life... parents suffering from drug and alcohol addiction...”
Svetlana devoted the next ten years of her life to refute each of these lines of that rotten textbook. Reset stigmas.
Today she is an activist in the public organization “He Needs You.” And her Alenka is a 10-year-old beauty and an excellent student. Her friends, wards, colleagues - hundreds of parents of children with hydrocephalus.
There is not a single person with addictions among them. The vast majority of cases of hydrocephalus she encounters are rooted in birth injuries and cerebral hemorrhages. A small percentage of children received congenital hydrocephalus (usually it is also associated with intrauterine injuries - accidents, etc.). And a small percentage of hydrocephalus is associated with infections suffered by the mother during pregnancy.
Treatment methods
Timely – early – intervention makes hydrocephalus not as fatal as before. Modern treatment methods save 95% of patients with a similar diagnosis. Surgery is virtually the only method of combating the disease. Drug methods in most cases can only slow down the course of the disease, but do not eliminate the root cause.
Modern techniques have many options for surgical treatment of hydrocephalus. In order to remove excess fluid from the cranial cavity, shunting is usually used. It consists of installing a shunt, which can be compared to a pipeline. It pumps out excess cerebrospinal fluid and pumps it into other cavities of the body - into the abdominal cavity, into the atrium.
Silicone valve systems are used as a shunt, which help regulate the pressure of cerebrospinal fluid in the cavities of the brain. The drainage system (shunt) and the level of pressure in it (in the case of programmable shunts) are selected by a neurosurgeon depending on the form of hydrocephalus and the age of the child. Bypass surgery is free and is included in the compulsory medical insurance list.
Endoscopic operations are also used as surgical treatment. The purpose of the endoscopic operation is to create an anastomosis (connection) between the cavity of the third ventricle and the basal cisterns (the second largest cavity of the brain, which is a reservoir for cerebrospinal fluid), located at the base of the skull. This operation is appropriate for outflow disorders in the posterior cranial fossa.
Endoscopic operations are also widely used when it is necessary to remove any obstacle to the movement of cerebrospinal fluid, for example, to remove a cyst. Without exception, all operations are aimed at restoring the balance between the production and absorption (discharge) of cerebrospinal fluid.
Development mechanism
CSF (cerebrospinal fluid) produced in the brain passes through the ventricles and is reabsorbed into the bloodstream from the subarachnoid space.
The process of production and absorption is balanced. If there is an imbalance in this process, it leads to hydrocephalus. Kinds:
1. According to the mechanism of occurrence:
- occlusal;
- open;
- hypersecretory.
2. By localization of fluid accumulation:
- external;
- internal;
- general (mixed).
3. According to the method of occurrence:
- congenital – occurs in the fetus in the prenatal period due to exposure to unfavorable factors (infectious, inflammatory diseases in a pregnant woman, spina bifida);
- acquired – occurs due to injury, brain tumor, intoxication, alcoholism, infectious diseases in adulthood.
Alenka: she can do anything!
For 10 years, Svetlana tirelessly explains to neurologists at appointments that a “ventricle” is not a “small stomach”, it is a part of the brain. And the shunt is not in my daughter’s stomach, but in her head.
But she is not tired, she is ready to continue doing this. Enlighten. Inspire. Inform.
“Why am I writing about my daughter and her successes? Sometimes you really want to climb deeper into the den and not let anyone in there. But I see how these posts inspire those parents who are just faced with this diagnosis. They see Alenka on a horse, at a reading competition, at a meeting with producer Maxim Fadeev - and believe in the best.
One day, Alenka, my eldest daughter Nastya, and I went on a horseback riding trip. I was nervous about my eldest and kept shouting to her: “Nastya, hold on! Nastya, hold on!”
Finally, the instructor couldn’t stand it and said: “Yes, she’s holding up better than anyone else,” and points to Alenka. I laugh: “Yes, I know, I’m shouting to the eldest.”
Alenka is confident both in the saddle and on stage. Not a single performance at school goes on without her. Even when she couldn’t walk yet, she played... Kolobok!
What she hasn’t been able to do yet is seriously take up music (we are often in hospitals, it’s difficult to organize a regular schedule of classes) and dancing (dances for wheelchair users are not suitable for her - she has already left the wheelchair, and the usual ones are not yet possible).”
But, looking at Alenka and her mother, we can confidently say: “This is not working out YET!” Once upon a time, doctors, looking at shunt-dependent Alena, only said: “Sit near the intensive care unit and don’t rock the boat!”
And only Dmitry Yuryevich Zinenko (now the head of the neurosurgical department of the Yu.E. Veltishchev Research Institute of Pediatrics) said: “You can do anything! Either fly into space or go diving.”
“It is no coincidence that all of us, his patients, are jokingly called “Zinen addicts.” He gave us a chance for an ordinary life.
Alenka, for example, does not allow me to stick a disabled sign on my car. And there are children with hydrocephalus who were not registered as disabled at all. They just live like everyone else. Of course, it is impossible to completely relax and not think about the shunt. In any state, I control it with at least the edge of my consciousness.
Didn't you fall? Did you hurt yourself? Doesn't she feel sick? If you feel sick, go straight to the ambulance and the hospital. If a child with a shunt vomits, the first thing we do is rule out problems with the shunt. Everything else is poisoning, infection - later. And yet I try not to get hung up on thoughts about the shunt, but just live. So, I think Alenka should still try to take up music: she has perfect pitch.”
Hospitalization and brain bypass surgery
After 1.5 months of observation with a neurosurgeon (we went to see him once every two weeks), we ended up in the Department of Neonatology, Neurology and Eye Microsurgery of the Morozov Children's City Clinical Hospital. We only needed a referral from the Vladimir doctors; we did not settle any formalities with the departments. Probably, if we had to do this, we could have lost precious time - queues and quotas wait for several months. That’s why the main thing I want to say to parents who are faced with the same problem as we are is that don’t be afraid to knock on closed doors. In such a situation, doctors do not refuse it to a child who really needs help.
On the first day after hospitalization, we were scheduled for a magnetic resonance imaging scan in order to make a final decision about surgery. The procedure is done under general but light anesthesia, the child “walked away” after it literally 5-10 minutes. Its cost is 10,000 rubles (as far as I know, it is not done for free at all). Lasts no more than 20 minutes.
After the tomogram was done, the son was included in the surgery schedule. We didn't wait long, literally 3 days. During this time, all the necessary examinations (ECG, blood and other tests) were completed. On day “x,” which I feared like nothing else in my life, the child was not allowed to eat from 3 a.m. (the operation was performed at 10 a.m.). It was quite difficult for him to withstand the test of hunger, but with joint efforts we managed.
The operation itself, under general anesthesia, lasted about 1.5 hours. Afterwards, the child was immediately brought to the recovery room, where we stayed with him for the next day. Then we returned to the department. He “recovered” from the anesthesia in front of me and after a couple of hours he felt as usual - he even smiled. The temperature did not rise.
As for payment for the operation, it itself is free, but the shunt system is purchased at the patient’s expense. At the moment when we were in the hospital, they were available in the department and we didn’t have to buy anything, so I don’t know how much they cost (approximately around 40,000 rubles).
Fitball exercises for kids
Review of the swimming pool of the Research Institute of Childhood Infections in St. Petersburg
Where to undergo rehabilitation after brain bypass surgery in a child
Dmitry Zinenko: hydrocephalus is a mysterious disease
– Hydrocephalus is the most mysterious disease of the central nervous system, which still does not have a generally accepted definition. But, despite this, we have learned to cure hydrocephalus,” says Dmitry Yuryevich Zinenko, head of the department of neurosurgery at the Research Institute of Pediatrics. – If you treat it on time and adequately, then it goes away without consequences for the child.
– Can I play sports?
– Children live full lives. True, it must be said that the cause of hydrocephalus can be: hypoxia, hemorrhage, trauma, infection and other diseases that are accompanied by brain damage, which determines the severity of the child’s condition, and not hydrocephalus as such. But it is hydrocephalus that can be recognized in a timely manner and adequately treated.
– Can specialists “overlook” it?
– Hydrocele of the brain is most often diagnosed in children under one year of age. It always occurs with increased intracranial pressure, which has clear manifestations: a rapid increase in head circumference, swollen veins on the head, and a swollen fontanel. A bright picture, impossible not to notice. If we talk about diagnostics, then more often we are dealing with overdiagnosis.
In 90% of cases, the diagnosis of “hydrocephalus” is made where it does not exist.
But when the patient has a shunt installed, then other problems appear. More often we encounter, on the contrary, an underestimation of the severity of the child’s condition. The pressure becomes low, not high. And this further hinders the child’s development.
Sometimes you have to deal with the following opinion: they installed a shunt, the ventricles got smaller – and that’s good. And if the child still cannot stand upright, this is perceived as a natural manifestation of the disease itself.
But in fact, if the ventricles have become smaller, this is a disaster. The head has stopped growing - this is a disaster. A child cannot stay upright for a long time - this is a disaster. These are all signs that the shunt is working too well. It is necessary to change the shunt and reduce the outflow of fluid. To save money, shunts are generally installed, which do not meet all the needs of the body.
- Poor quality?
– How can I tell you... You can buy a Zhiguli. Good car. But she has her limits. Or you can buy a Mercedes. It has more opportunities and higher security. But the price is different. That's how it is with shunts. Unfortunately, fixed pressure shunts are such “Zhiguli”. They are available, but lead to a huge number of complications. It's like a faucet that is always open to the same flow of liquid, which may not be suitable for a particular child.
You need to immediately install a programmable shunt. Then we can regulate the outflow of fluid for each child individually without repeated operations. They are expensive, but in the long run they avoid many complications and would be cheaper overall for the health care system. And most importantly, it’s safer for the child.
– You operated on little Matvey together with the famous Indian surgeon Sandeep Vaishya, when you reduced the volume of his head, a consequence of hydrocephalus. Was this a unique experience for you?
– Of course, any exchange of experience is priceless. We also perform such operations, but it was useful to work with an excellent surgeon, see his technique, and discuss approaches. This operation is exclusive today only because such large heads have become rare these days. Hydrocephalus can be successfully treated in the early stages. You don't have to wait until your head gets that big.
Birthday head: volunteer surgeons treat orphans with hydrocephalus
Coronary artery bypass grafting (CABG) is one of the main methods of surgical treatment of coronary heart disease and is performed to restore perfusion and improve the functional state of the myocardium. CABG is associated with a variety of negative factors and the risk of brain damage [5]. Reports of a high percentage of severe neurological complications, and primarily stroke (up to 20%) after CABG, have appeared since the 70s. last century. Initially, neurological complications of CABG were associated with the widespread use of artificial circulation (CPB) [47, 71]. The development of anesthesia and perfusionology, improvement of surgical techniques has made it possible to significantly reduce the number of severe neurological complications. However, it has become obvious that up to 80% of patients in the postoperative period have mild or moderate brain damage, which is manifested primarily by cognitive decline [17].
Classification of neurological complications of CABG
Neurological complications of CABG are usually divided into focal, clinically manifested by transient ischemic attack or stroke, and multifocal, or diffuse, which is essentially acute hypoxic-ischemic encephalopathy (HIE). Clinically, HIE may manifest as transient disturbances of consciousness, short-term cognitive impairment, or persistent cognitive deficits [20]. Stroke after CABG develops in 1-6% of patients [62, 64, 66, 73], and acute HIE - in more than 70%. In HIE after CABG, impaired consciousness occurs in 15% of cases, short-term cognitive impairment in 25%, and persistent cognitive deficit in 42%.
With the introduction of magnetic resonance imaging (MRI) in the second half of the 1990s. The diagnosis of stroke in patients after CABG has significantly improved, and it is possible to differentiate between “old” damage, common in this category of patients, and new stroke [1, 15]. In more than half of patients with ischemic stroke after CABG, the lesion is localized in the area of adjacent blood supply, located on the border of two vascular territories. The development of such strokes is associated with a decrease in cerebral perfusion [80]. In 18–62% of patients after CABG using IR, “silent” infarctions are detected by neuroimaging [44]. The clinical significance of these infarcts is still unclear; in some studies they were clinically associated with postoperative disturbances of consciousness or cognitive dysfunction [75], while in other studies this association was not found [15].
On the 1st day after surgery, a disturbance of consciousness may develop, expressed in short-term episodes of disorientation, delirium, delayed awakening after anesthesia, stupor or coma [20]. Impaired consciousness is particularly common in older patients and is associated with higher postoperative mortality [22]. Postoperative impairment of consciousness, in addition to hypoxic-ischemic brain damage, has other causes: the effect of certain drugs, metabolic disorders or intercurrent diseases [42].
It was previously believed that postoperative depression was the basis for complaints of decreased memory and other cognitive functions after CABG [37]. The most common disorders are attention and memory impairments, decreased speed of psychomotor reactions, impaired activity planning, and visuospatial impairments [42, 63]. The development of cognitive impairment is influenced by the duration of cardiopulmonary bypass, temperature, blood pressure (BP) parameters, and intraoperative embolism. Cognitive impairment in the first days after surgery may be associated with the negative effects of general anesthesia and pain medications [8, 42]. Despite the large number of studies performed to date, the underlying cause of postoperative cognitive decline has not been established [56]. A number of recent prospective studies have demonstrated that in a significant proportion of patients, cognitive decline after CABG is reversible, and most patients return to baseline cognitive status between 3 and 12 months after surgery [56, 68].
However, in 42% of patients, cognitive decline persists 5 years or more after CABG. Factors contributing to the development of persistent cognitive deficits are a lower educational level, older age, and a pronounced decline in cognitive functions at the preoperative stage [72]. Some studies have noted a low incidence of persistent cognitive impairment, which may be explained by more stringent control of current arterial hypertension (HTN), hypercholesterolemia and other risk factors for cerebrovascular pathology [29, 61]. Thus, persistent cognitive deficit may be due not so much to the previous CABG with CPB, but to the progression of cerebrovascular pathology associated with damage to small subcortical vessels, the development of “silent” infarctions [75] and current neurodegenerative diseases, such as Alzheimer’s disease [7, 29].
As age increases, the risk of stroke or cognitive impairment increases in the general population, and surgery, regardless of type, further increases this risk [53, 71]. It has been shown that in patients undergoing cardiac surgery at 60 years of age, the risk of stroke increases twice as compared to non-surgical patients, and in patients 70 years of age it increases 7 times [52]. Hypertension occurs in approximately 60% of patients requiring cardiac surgery, and diabetes mellitus in 25%. Approximately 15% of patients have more than 50% stenosis of the carotid arteries and 13% have a history of TIA or previous stroke [31]. Severe aortic atherosclerosis occurs in 1% of patients under the age of 50 years and in 10% of patients aged 75–80 years [73].
Thus, the main risk factors for neurological complications of CABG are age, concomitant diseases (hypertension, diabetes mellitus, vascular diseases such as atherosclerosis of the aorta, great vessels of the head or extremities, previous stroke and lung diseases), as well as alcohol abuse, smoking and preoperative cognitive impairment. decrease [31].
Mechanisms of brain damage in CABG
There are three main mechanisms of brain injury in CABG: embolism, hypoperfusion, and systemic inflammatory response. All of them can occur in a patient in different proportions at the same time, explaining the variety of neurological complications [18, 58]. Atherosclerotic aortic embolism and insufficient perfusion in watershed areas are believed to be the main causes of stroke after cardiac surgery [32]. Micro- and macroemboli during surgery can consist of atherosclerotic debris, lipid inclusions or air [27, 54].
Certain surgical steps, such as initiation and termination of CPB, application/removal of aortic clamps and other manipulations of the ascending aorta, as well as initiation and clearance of cardioplegia, may be associated with cerebral embolism [21, 62]. Embolic strokes that develop during CABG are often localized in the posterior parts of the brain, affecting the cerebellar and posterior cerebral arteries [17]. Macroembolism can occur when aortic atheroma is destroyed during surgery [1, 31], from the great vessels of the head and neck, or during atrial fibrillation. Aspiration of blood spilled during cardiotomy has been identified as an important source of cerebral microembolism, since it is associated with the reinfusion of air and lipids of cellular fragments of the pericardial cavity, capable of penetrating through arterial network filters [77]. Capillary-arteriolar microdilatations in the cortical and deep gray matter of the brain, associated with lipid microembolism, were found to be pathognomonic for operations with IR. Their presence was confirmed by transcranial Doppler sonography, retinal fluorescent vasography and autopsy studies [17]. Autopsy demonstrates that almost all people who have undergone CABG have signs of cerebral embolism in the form of capillary-arteriolar microdilatations, but their clinical significance is still unclear.
Large air embolisms in cardiac surgery are extremely rare and are usually associated with a violation of the technique of performing medical procedures [34]. Air microembolism during CABG occurs due to air entering the arterial and venous systems [59].
Approximately 1/3 of patients undergoing CABG develop atrial fibrillation, which increases the risk of thrombus formation and stroke in the late postoperative period [50].
Some studies have shown a relationship between microembolic volume and short-term cognitive impairment. It has been suggested that patients without significant cerebrovascular disease may have a higher threshold for embolic injury than those with significant disease [35].
Significant hypotension during CABG increases the risk of postoperative stroke and other neurological complications. There is evidence that patients with a decrease in systolic blood pressure to 50 mm Hg. or lower for at least 10 minutes, were 4 times more likely to have postoperative neurological complications [25]. This is of particular importance for patients suffering from chronic hypertension, leading to structural changes in the microvasculature and disruption of the mechanisms of self-regulation of cerebral blood flow. Hypotensive damage can develop in the structure of general ischemic damage and manifests itself predominantly in areas of adjacent blood supply. The parieto-occipital region and cerebellum are most often affected [32, 78].
Anemia has an effect similar to hypoperfusion. It is known that each additional 1% decrease in hematocrit increases the likelihood of postoperative stroke by 10%. The effects of underperfusion and their relationship with blood pressure and anemia still require further investigation [41].
Long-term hypertension and the aging process are associated with damage to small cerebral vessels, which may make older patients more susceptible to poor perfusion [13]. The hippocampus, periventricular white matter, and areas of adjacent blood supply are particularly susceptible to hypoperfusion [7].
A hyperthermic state can cause brain damage due to inadequate oxygen delivery to the brain coupled with increased cerebral blood flow. Microemboli may also cause more damage during hyperthermia [57].
Any surgical operation, like an accidental injury, triggers a complex of inflammatory reactions in the body [11]. In CABG surgery, this is accompanied by an additional anticoagulant load, blood reinfusion, and blood contact with the IR device, which lead to additional damage to the endothelium, increasing the size of ischemic damage [76].
The pathogenetic basis of brain damage is ischemia, i.e. a decrease in cerebral blood flow below the level that can meet the metabolic needs of the neuron [6, 11]. In this regard, there is a clear distinction between the concept of ischemia and hypoxia, which characterizes a condition associated with insufficient oxygen delivery. While in many pathological processes both mechanisms are interrelated, when present simultaneously, hypoxia enhances ischemic damage [51].
It is known that neuronal groups differ in sensitivity to ischemia, which is reflected in the term “selective neuronal necrosis” [14]. Structural brain damage that develops after cessation of cerebral blood flow during cardiac arrest is consistent with the principle of selective neuronal sensitivity, and pathological changes are associated with a period of suffering of individual subpopulations of neurons. The earliest changes were seen in the CA1 sector of the hippocampus, Purkinje cells of the cerebellum, striatum and thalamus. Neurons of the CA1 sector (one of the most vulnerable areas of the brain during ischemic exposure) die very quickly. In the cerebral cortex, the most sensitive neurons are layers 3, 5, and 6, as well as neurons located deep in the sulci [74]. Stem structures are relatively stable. The outcome of such damage is hippocampal sclerosis, neocortical lamellar necrosis, cerebellar atrophy and secondary atrophy of the periventricular white matter [64]. With continued ischemic exposure, acidosis develops, and, in addition to neurons, other types of cells (astrocytes, oligodendrocytes, vascular smooth muscle cells, endothelial cells) begin to suffer. Disruption of normal cellular structure activates macrophages, and a process called wet necrosis occurs [11]. Gradually, as necrotic tissue is removed, a glial scar is formed; this process takes several weeks.
Selective cell death is based on mechanisms of excitotoxicity, realized through activation of NMDA receptors [19, 64], including through excessive production and release of the excitatory neurotransmitter glutamate. Hyperstimulation of NMDA receptors activates a number of intracellular enzymes (kinases, proteases, phosphatases and endonucleases), while the synthesis of lactate increases, the intracellular concentration of calcium ions increases, the synthesis of nitric oxide and its derivatives increases, the accumulation of reactive oxygen species occurs, energy reserves are depleted, direct damage to DNA and mitochondria, ultimately leading to neuron death [78].
The process of so-called delayed neuronal death is known, which occurs during episodes of ischemia that occur, for example, during short-term cardiac arrest. This process can lead to the formation of an area of ischemic damage over several days or weeks [36].
A very special form of brain damage occurs in situations involving long-term disruption of brain perfusion. The increasing resistance of the cerebral vessels prevents the restoration of any significant perfusion, and brain asphyxia occurs. Pathomorphologically, in this case, it is not the formation of an infarction that occurs in the brain, but the process of autolysis [11, 51].
Diagnosis of brain damage in the event of clinical stroke development is relatively simple, especially with the availability of neuroimaging [79]. To identify cognitive dysfunction, neuropsychological tests have been developed that allow a comprehensive assessment of the patient’s deficit. However, the use of these tests is limited in the early postoperative period by their labor intensity and the need for active cooperation with the patient [75], so other options for diagnosing brain damage are being sought [39, 40].
Potential biomarkers of brain injury include S100 protein, neuron-specific enolase, glial fibrillary acidic protein, myelin basic protein, tau protein, fatty acids, anti-NMDA receptor antibodies, nitric oxide products (nitrate/nitrite), activin A, parvalbumin, thrombomodulin [40]. The current lack of a single verified universal marker of brain injury is associated with the complex pathophysiology of the process, insufficient understanding of intra- and extracellular protein interactions, and the effect of the blood-brain barrier, which limits laboratory diagnostics [4, 48].
Neuroprotection Strategies
The main direction of neuroprotection in cardiac surgery is comprehensive protection of the brain from embolism [3, 43]. In principle, this is accomplished by the use of anticoagulant therapy, washing blood from wound aspirate, filtering arterial inflow and venous outflow, strict control of all air entries into the oxygenator, removing air from the heart and large vessels, and preventing atherosclerotic embolism [65].
Ultrasound examination of the ascending aorta is the most sensitive method for identifying intact zones free of atheromatosis. To reduce the risk of intervention in the ascending aorta, depending on the detected degree and extent of the process, surgeons may use alternative cannulation sites (for example, through the axillary artery), avoid partial occlusion of the aorta to apply a nearby shunt, and perform, as an alternative, complete transverse clamping of the aorta, simultaneous replacement of the ascending aorta [26] or the use of bypass surgery without CPB [33].
It was experimentally established that conventional arterial AC filters are ineffective against lipid microemboli contained in wound aspirate [43]. Pretreatment of the aspirate with the Sell Sever or double filtration of the aspirate before returning it to the CPB system significantly, but not completely, reduces the microembolic load, and lipid microparticles remain in the pericardial aspirate with any processing. Therefore, it is advisable to refuse pericardial aspirate in cases where its quantity is small [70]. It has been shown that processing large quantities of aspirate with the Sell Sever device can lead to thrombocytopenia and a decrease in the amount of anticoagulation factors, increasing the risk of postoperative bleeding. This forces the transfusion of blood components and, first of all, platelets, increasing the risk of stroke.
It is believed that maintaining blood pressure at 50 mm Hg. is sufficient to ensure adequate oxygenation of the brain, since the existing independent regulation of cerebral blood flow under these conditions maintains its adequate perfusion [60]. Higher perfusion pressure numbers increase the risk of embolism [27]. Most specialists, when maintaining a certain level of blood pressure during cardiopulmonary bypass, focus on the progression of cerebral vascular pathology with age and use a formula for matching age and pressure (for example, over 70 years old - 70 mm Hg, over 80 years old - 80 mm Hg).
A promising, but currently not tested in humans, means of protection against cerebral air embolism is the technique of replacing air in the pericardium with CO2, since it is more soluble in the blood than air [49].
Hemodilution is used during CPB to reduce blood viscosity caused by hypothermia and reduce the need for blood transfusion. The brain compensates for the decrease in the oxygen capacity of the blood by increasing perfusion and increasing O2 extraction by tissues. However, a decrease in hematocrit <22% during CPB is significantly associated with the development of stroke after CABG. Thus, the optimal hematocrit level for humans during CPB is uncertain and likely varies depending on many factors, including body temperature and individual risk of ischemic brain injury.
Creating hypothermic conditions protects the brain from ischemic damage through several mechanisms, including a decrease in O2 demand and a decrease in excitotoxicity processes [10, 38]. It has been clinically proven that overheating to a nasopharyngeal temperature of 34 °C after CPB under hypothermia conditions (32 °C) led to a low incidence of cognitive dysfunction 1 week and 3 months after CABG compared with overheating to 37 °C [2, 57].
Stress hyperglycemia during stroke occurs in more than 1/3 of patients without baseline diabetes mellitus and in most patients with diabetes [3, 46]. Numerous studies have not demonstrated unequivocal results of insulin therapy and the benefits of glycemic control to provide a neuroprotective effect in patients with CABG. It has been shown that maintaining hyperglycemia above 20.0 g/l during 24 hours of ischemic stroke leads to expansion of the infarct zone [23]. The guidelines of the American Heart Association in situations with developed ischemic stroke recommend the initiation of insulin therapy when the glycemic level increases more than 14.0 g/l [28].
Off-pump CABG has been proposed as a means of reducing neurological complications by reducing the risk of embolic complications and the severity of systemic inflammatory reactions. However, recent data from prospective randomized trials have shown no significant differences between these methods in the incidence of either early or late neurological complications [55].
For neuroprotective purposes, drugs of various groups are used, the basis of their action is the regulation of various parts of the pathogenesis of neuronal death, for example, NMDA receptor antagonists (memantine), NO synthetase inhibitors (L-nitroarginine), barbiturates, anesthetic drugs, high doses of steroids, xanthine oxidase inhibitor allopurinol , diuretic mannitol, calcium antagonists, β-blockers, proteolytic enzyme inhibitor aprotinin, anticonvulsants [30]. The potential neuroprotective capabilities of lidocaine, a polarizing glucose-potassium-insulin mixture, the immunosuppressant cyclosporine, erythropoietin, aspirin, GM1-ganglioside, high-energy substrates such as fructose-1,6-biphosphate [67] and others are being considered.
Modern discoveries of molecular biology have proven the existence of a universal cellular mechanism that provides ischemic preconditioning [24]. This is a unique adaptive phenomenon that occurs after one or several short episodes of ischemia-reperfusion and consists of increasing the cell’s resistance to the damaging effects of a long period of ischemia-reperfusion, which is generally realized through improving the bioenergetics of mitochondria [12]. It is assumed that inhalational anesthetics, such as isoflurane and sevoflurane [45], as well as the antihypertensive drug diazoxide [69], have a preconditioning effect based on depolarization of mitochondrial membranes and protection of the blood-brain barrier from ischemic stress. The clinical effectiveness of these drugs as neuroprotectors remains to be investigated.
The facts presented in this review provide grounds to draw the attention of doctors, primarily surgeons and neurologists, to the possibility of developing neurological complications during coronary artery bypass grafting and the associated need for a targeted examination of the patient to provide timely assistance in the form of active measures for neuroprotection.
Matvey: waiting for his mother
Matvey's head grew so large from hydrocephalus that until he was three years old he could not even lift it. No, not by oversight. Yes, the young 17-year-old mother abandoned him immediately after giving birth. But the caring hands of Elena Evgenievna Shatskaya, the head physician of that institution for orphans in the Ryazan region, who accepted Matvey, and her colleagues did everything possible for him. And even the impossible. Bypass surgery, shunt testing, replacement. Everything was complicated by a congenital brain defect.
When the capabilities of regional neurosurgeons were exhausted, Elena Evgenievna reached the federal ones. And now a unique operation to reduce the head (cranioplasty) of three-year-old Matvey was performed in two stages by the best Russian neurosurgeons together with the invited Indian surgeon Sandeep Vaisha.
After the first operation, the baby turned over on his stomach, and after the second, he began to get up on all fours and raise his head.
Today, 4-year-old Matvey can sit down on his own and remain in a sitting position for quite a long time. This means that now he eats and walks while sitting. His diet has expanded (it turns out he loves bananas and strawberry curds), his visibility has increased, and new emotions have appeared.
– Even such a difficult combination of diagnoses is not a reason to “give up” on a child. We cannot guarantee him the ordinary life of an ordinary baby, but we can improve the quality of his life, give him a chance, and use the rehabilitation potential that he has. I don’t know if he will study in a regular school, but there is hope that he will go!
Our most important worry is that in a year we are obliged to transfer our smiling boy to a boarding school for children with severe mental retardation. But if only he had a family! We would be very happy to provide them with all our rehabilitation opportunities,” Elena Evgenievna dreams. “I’m sure he will make someone’s parental happiness!”
Brain shunting for hydrocephalus: consequences of the intervention
When choosing treatment tactics, the doctor informs the patient about possible risks. The patient must understand that if he has hydrocephalus, shunting may have consequences. After surgery, the patient may experience problems such as:
- arrhythmia;
- internal bleeding;
- arterial thrombosis;
- pain in the wound area;
- disruption of blood flow in the brain;
- myocardial infarction;
- infection.
These complications arise against the background of the patient’s circulatory system diseases, in particular heart disease, immune diseases, and vascular atherosclerosis. The risk of consequences is highest in older people, women, and those with other diseases.
Bypass surgery at the Yusupov Hospital is performed by experienced neurosurgeons, so the likelihood of consequences is significantly reduced. In addition, before prescribing an operation, the neurologist takes into account all available factors when making a decision.
Hydrocephalus: symptoms
If you notice the following symptoms in your little child:
– rapid increase in head circumference, – enlarged and swollen fontanel, – pronounced venous pattern on the forehead and face, – oculomotor disorders (strabismus, setting sun symptom, congestion of the optic nerves), – if the child does not hold his head up, throws it back, – eats poorly, sleeps poorly, cries often -
Contact a neurologist immediately! Time in this case can work against you!
Your actions:
STEP 1. Get a referral from a neurologist for an examination (MRI or CT). All examinations are carried out within the framework of compulsory medical insurance! MRI is performed free of charge for young children; the examination is performed under general anesthesia in a day hospital.
STEP 2. Contact a neurosurgeon with the results of the examination. If there is no neurosurgeon in the region (or to get a “second opinion”), send the results of the examination (MRI image) for an online consultation at a specialized clinic (the consultation is free, the contacts of medical organizations are in the memo) or to the post office of the municipal non-profit organization “He Needs You” marked “for consultation”
STEP 3. The hospital conducts an absentee medical consultation based on the medical documents you provided and, if hospitalization is necessary, prepares a voucher for you, which will indicate the date of hospitalization, a list of tests for the child and accompanying person, doctor’s contacts, hospital address and other important information.
STEP 4. When a diagnosis of Hydrocephalus is made based on MRI results, surgical treatment is performed. The method of surgical intervention is determined by the neurosurgeon depending on the type of disease.
Varenka: the suffering was associated with the shunt
– Even as a child, I knew that I would have a son, Stepka, and a daughter, Varenka. But somehow it didn’t work out,” says Elena Kirina from the city of Sortavala (Karelia). My husband and I did not have children for seven years. They were examined and treated. Finally they told me that I was pregnant and had twins, I fell to the floor with joy and began to cry. And then at 14 weeks, on an ultrasound, it became clear that Varyusha has Dandy-Walker syndrome, the cerebellum is not developing and she most likely will not survive, and if she survives, she will become disabled. They offered us an abortion, but Styopka could have been harmed during the abortion. And in general, I have always been against abortion. We decided to give birth. I cried for the rest of the pregnancy. At 33 weeks labor began. They performed a caesarean section. I didn’t see Varya at all - she wasn’t breathing, they immediately took her away.
On the 9th day, Varya began to develop hydrocephalus. At three months she had her first shunt installed. But the girl suffered. In total, she underwent eight surgeries. Her shunt was clogged and her cerebrospinal fluid was infected. In essence, she was doomed. She spent a whole year in hospitals in Petrozavodsk and St. Petersburg. And Lena, who could not leave Stepan for long (he also had health problems), spent more time on the road this year than with her daughter.
“I had a small child at home, and I cried endlessly and wanted to strangle myself. Because my other child was dying alone in the hospital.
The problem was that Varya was kept in the infectious diseases department, believing that her symptoms were a consequence of the virus. And her suffering was associated precisely with the shunt.
Shunt dependent
When discharging a child from the hospital, you must insist that the brand, model of the drainage system (shunt) and pressure level (in the case of programmable shunt models) be included in the discharge. This is vital in emergency situations (eg shunt dysfunction) and when measuring pressure if overdrainage is suspected. Each programmable shunt has its own pressure setting system!
Not all types of shunt can pass through metal detectors. The drainage system settings may fail.
Avoid overheating (baths, long exposure to the sun), hypothermia, head injuries, electromagnetic treatment. Every time a child has been exposed to intense magnetic fields, check the pressure level setting of the valve.
Do not massage the head, neck and abdomen area.
If the drainage system is not functioning well, signs of shunt dysfunction appear, which are manifested in the following symptoms: increased intracranial pressure, headaches, nausea, vomiting, decreased level of spontaneous activity.
If you have a fever in combination with other suspicious symptoms (vomiting, lethargy), immediately contact a neurologist or neurosurgeon!
Symptoms
Symptoms depend on the patient’s age and concomitant diseases.
In adults, hydrocephalus is manifested by the following symptoms:
- headache (usually in the morning);
- decreased visual acuity;
- nausea;
- dizziness;
- memory impairment;
- vomit;
- limited movement of the eyeballs;
- emotional lability;
- impaired coordination of movement, concentration of attention;
- head size is not increased.
Varenka: they weren’t the ones who pulled them out!
When Lena brought her Varya home to Sortavala one year ago, and she was admitted to their local hospital, the doctors threw up their hands in bewilderment:
“We’ll lie down and watch.” - You mean die? - Well, yes.
And then Lena realized that she couldn’t just wait for her daughter to die. She called a paid ambulance and rushed to St. Petersburg. And from there by train, with Varya in her arms, to Moscow. “She will die on your way!” - they told her goodbye at the hospital. But she found a paid doctor who would accompany her and went.
She already knew that in Moscow there was Dmitry Zinenko, for whom hydrocephalus was not a death sentence or a horror story.
“And they weren’t the ones who pulled it out,” said Dmitry Yuryevich, looking at Varya, whose head weighed four kilograms out of six kilograms of total weight.
In Moscow, Vara was fitted with a new shunt, brought into the atrium, and later into the abdominal cavity. And the girl came to life. Lena and Varya completed two courses at the St. Petersburg rehabilitation center. And after the first year, Varya began to raise her head. And a year later she began to roll over, crawl, sit up and walk along the support.
– The main thing is that we are now at home and all together! – Lena couldn’t be happier.
Three-year-old Styopa, developed for his age, dashingly climbed onto a chair and reached for the paints that his mother had hidden. And now she and Varya are already painting something on the floor. They worked well together - twins.
“The relatives in Var dote on their souls,” says Lena. “And the main thing is that since Varya returned home, we never have quarrels, no one yells at anyone. Unless the children fight with each other sometimes. Well, children!
