Faint (syncope) — the temporary loss of consciousness caused by tranzitorny general hypoperfusion of a brain. The clinic to a syncope consists of harbingers (shortage of air, "faintness", fog or "front sights" before eyes, dizziness), the period of lack of consciousness and a recovery stage in which weakness, hypotonia, dizziness remains. Diagnostics of sinkopalny states is based on data of the tilt-test, clinical and biochemical analyses, the ECG, EEG, UZDG of ekstrakranialny vessels. The differentiated therapy directed to elimination of etiopatogenetichesky mechanisms of development of paroxysms is, as a rule, applied to patients with faints. In the absence of convincing data on genesis to a syncope undifferentiated treatment is performed.
The faint (a sinkopalny state, a syncope) was regarded as tranzitorny loss of consciousness with loss of a posturalny tone earlier. Really, frustration of a muscular tone leads to falling of the person at a faint. However such definition is fitted by many other states: different types of epipristup, hypoglycemia, ChMT, TIA, sharp alcoholic intoxication and so forth. Therefore in 2009 other definition treating a faint as the tranzitorny loss of consciousness caused by the general cerebral hypoperfusion was accepted.
According to the generalized data to 50% of people at least 1 time during the life had a faint. As a rule, the first episode falls a syncope on the period of 10-30 years, with peak at pubertatny age. Population researches indicate that the frequency of sinkopalny states increases with age. At 35% of patients the repeated faint arises within three years after the first.
The global passing cerebral ischemia causing a faint can have the most various reasons as nevrogenny, so somatic character. A variety of etiopatogenetichesky mechanisms and its incidental character explains to a syncope the considerable difficulties arising at doctors in diagnostics of the reasons and the choice of medical tactics at a faint. The aforesaid emphasizes the cross-disciplinary relevance of this problem demanding participation of experts in the field of neurology, cardiology, traumatology, endocrinology, pediatrics and psychiatry.
Causes of a faint
Normal the blood-groove on brain arteries is estimated within 60-100 ml of blood on 100 g of brain substance a minute. Its sharp decrease to 20 ml on 100 g a minute causes a faint. Can act as the factors causing sudden decrease in volume of the blood coming to cerebral vessels: reduction of warm emission (at a myocardial infarction, massive sharp blood loss, heavy arrhythmia, ventricular tachycardia, bradycardia, a gipovolemiya owing to profuzny diarrhea), narrowing of a gleam of the arteries feeding a brain (at atherosclerosis, occlusion of carotids, a vascular spasm), dilatation of vessels, bystry change of position of a body (a so-called orthostatic collapse).
Change of a tone (dilatation or spazmirovaniye) of the vessels feeding a brain often has neuroreflex character and is the leading reason to a syncope. The similar faint can provoke strong psychoemotional experience, pain, irritation of a carotid sine (at cough, swallowing, sneezing) and the wandering nerve (at an otoskopiya, a gastrokardialny syndrome), an attack of sharp cholecystitis or renal colic, trigeminal neuralgia, neuralgia of a yazykoglotochny nerve, an attack of vegeto-vascular dystonia, overdose of some pharmaceuticals, etc.
Other mechanism provoking a faint is decrease in oxygenation of blood, i.e. decrease in content of oxygen in blood at normal OTsK. To a syncope of such genesis it can be observed at blood diseases (iron deficiency anemia, crescent and cellular anemia), poisoning with carbon monoxide, diseases of respiratory organs (bronchial asthma, obstructive bronchitis). Also reduction of content in CO2 blood can cause a faint that is often observed at a hyperventilation of lungs. According to some information, about 41% are the share of a faint which etiology does not manage to be established.
Classification of faints
Attempts of systematization of various types of a faint led to creation of several classifications. The etiopatogenetichesky principle is the cornerstone of most of them. Carry vazovagalny states which cornerstone the sharp vazodilatation, and irritativny is to group of neurogenetic faints (a syndrome of a carotid sine, faints at yazykoglotochny and trigeminal neuralgia). To orthostatic the syncope possesses the faints caused by vegetative insufficiency, decrease in OTsK, the medicamentous induced orthostatic hypotonia. The faint of cardiogenic type arises owing to cardiovascular diseases: hypertrophic cardiomyopathy, stenosis of a pulmonary artery, aortal stenosis, pulmonary hypertensia, miksoma of auricles, myocardial infarction, valvate heart diseases. The Aritmogenny faint is provoked by existence of arrhythmia (AV-blockade, tachycardia, SSSU), failure in work of an electropacemaker, side effect of antiaritmik. Allocate also tserebrovaskulyarny (distsirkulyatorny) faint connected with pathology of vessels, krovosnabzhayushchy cerebral structures. Faints which trigger factor did not manage to be established carry in group of atypical.
Clinical picture of a faint
The maximum duration of a sinkopalny state does not exceed 30 minutes, in most cases the faint lasts no more than 2-3 minutes. Despite it, during a faint 3 stages are obviously traced: presinkopalny state (period of harbingers), actually faint and postsinkopalny state (restoration period). The clinic and duration of each stage are very variable and depend on the pathogenetic mechanisms which are the cornerstone of a faint.
The Presinkopalny period lasts several seconds or minutes. It is described by patients as feeling of faintness, sharp weakness, dizziness, shortage of air, a sight zatumanivaniye. Nausea, flashing of points before eyes, a ring in ears is possible. If the person manages to sit down, having hung the head, or to lay down, then losses of consciousness can not occur. Otherwise increase of the specified manifestations comes to an end with loss of consciousness and falling. At slow development of a faint the patient, falling, keeps for surrounding objects that allows it to avoid traumatizing. Quickly developing sinkopalny state can lead to serious consequences: To ChMT, change, spine injury, etc.
In the period of actually faint the consciousness loss, various on the depth, which is followed by superficial breath, full muscular relaxation is noted. At survey of the patient in the period of actually faint also the slowed-down reaction of pupils to light, weak filling of pulse, arterial hypotonia is observed . Tendinous reflexes of a sokhranna. Deep disorder of consciousness at a faint with the expressed cerebral hypoxia can proceed with developing of short-term spasms and an involuntary urination. But the similar single sinkopalny paroxysm is not a reason for diagnosing of epilepsy.
The Postsinkopalny period of a faint, as a rule, lasts no more than several minutes, however 1-2 hours can proceed. Some weakness and uncertainty of movements is observed, the dizziness lowered HELL and pallor remains. Dryness in a mouth, is possible. It is characteristic that patients well remember everything that occurred until consciousness loss. This feature gives the chance to exclude ChMT for which existence of retrograde amnesia is typical. Lack of neurologic deficiency and all-brain symptoms allows to differentiate a faint from ONMK.
Clinic of separate types of a faint
Vazovagalny faint — the most frequent type of a sinkopalny state. Its pathogenetic mechanism consists in a sharp peripheral vazodilatation. Long standing, stay in the stuffy place, an overheat can act as the trigger of an attack (in a bath, on the beach), excess emotional reaction, a painful impulse, etc. the Vazovagalny sinkopalny state develops only in a vertical state. If the patient manages to lay down or sit down, to leave the stuffy or hot room, then the faint can terminate at a presinkopalny stage. The expressed staging is characteristic of vazovagalny type to a syncope. The first stage lasts to 3 mines for which patients manage to tell people around that to them it is "bad". The stage actually of a faint proceeds 1-2 min., HELL with threadlike pulse at normal ChSS is followed gipergidrozy, pallor, muscular hypotonia, falling. In a postsinkopalny stage (of 5 min. to 1 h) to the forefront there is a weakness.
The Tserebrovaskulyarny faint often arises at backbone pathology in cervical department (a spondiloartroza, osteochondrosis, a spondileza). The Patognomonichny trigger of this type of a faint is the sharp turn by the head. The sdavleniye of a vertebral artery occurring at the same time leads to the sudden brain ischemia involving consciousness loss. At a presinkopalny stage fotopsiya, noise in ears, sometimes — an intensive tsefalgiya are possible. Actually the faint is characterized by sharp weakening of a posturalny tone that remains in a postsinkopalny stage.
The Irritativny faint develops as a result of reflex bradycardia at irritation of the wandering nerve impulses from its receptor zones. Emergence of such faints can be observed at an akhalaziya of a sebesten, stomach ulcer 12-p guts, giperkineziya of bilious ways, etc. the diseases which are followed by formation of abnormal vistsero-visceral reflexes. The trigger, for example, a specific attack of pain, swallowing, carrying out gastroscopy has each appearance of an irritativny faint. This type of a sinkopalny state is characterized short, only several seconds, by the period of harbingers. Consciousness is disconnected for 1-2 min. the Postsinkopalny period often is absent. As a rule, repeated stereotypic faints are noted.
Kardio-and the aritmogenny faint is observed at 13% of patients with a myocardial infarction. In such cases to a syncope is the first symptom and seriously complicates diagnosis of the main pathology. Features are: emergence irrespective of position of the person, existence of symptoms of a cardiogenic collapse, a deep water of loss of consciousness, repetition of a sinkopalny paroxysm in attempt of the patient to rise after the first faint. The Sinkopalny states entering into clinic of a syndrome of Morganyi-Edemsa-Stoksa are characterized by lack of harbingers, impossibility to define pulse and heartbeat, the pallor reaching cyanosis, the beginning of restoration of consciousness after emergence of warm reductions.
The orthostatic faint develops only during transition from a horizontal position in vertical position. It is observed at hypotensives, persons with vegetative dysfunction, the elderly and weakened patients. Usually such patients point to numerous cases of dizziness or "zatumanivaniye" at sharp change of position of a body. Often the orthostatic faint is not a pathological state and does not demand additional treatment.
The careful and consecutive poll of the patient directed to identification of the trigger which provoked a faint and the analysis of features of clinic of a sinkopalny state allows the doctor to establish faint type, adequately to define need and the direction of diagnostic search of the pathology standing for a syncope. At the same time the exception of urgentny states which can demonstrate a faint is prime (TELA, sharp ischemia of a myocardium, bleeding and so forth). At the second stage establish whether is to a syncope display of an organic disease of a brain (aneurisms of cerebral vessels, an intracerebral tumor, etc.). Primary inspection of the patient is performed by the therapist or the pediatrician, the neurologist. Further consultation of the cardiologist, an epileptolog, the endocrinologist, psychiatrist, etc. narrow experts can be required.
From laboratory methods with genesis diagnostics the syncope is helped by the general analysis of urine and blood, a research of gas composition of blood, blood sugar definition, carrying out the glyukozo-tolerant test, biochemical blood test. With sinkopalny states usually are in the plan of inspection of patients: ECG, EEG, REG, Ekho-EG, UZDG of ekstrakranialny vessels. At suspicion in addition appoint to the cardiogenic nature of a faint ultrasonography of heart, a phonocardiography, daily monitoring of the ECG, load tests. If assume organic damage of a brain, then carry out MCKT or MPT of a brain, MRA, duplex scanning or transkranialny UZDG, a backbone X-ray analysis in cervical department.
In diagnostics of sinkopalny conditions of uncertain genesis broad application was found by the tilt-test allowing to define the emergence mechanism to a syncope.
First aid at a faint
Creation of the conditions promoting the best oxygenation of a brain is paramount. For this purpose the patient is given horizontal position, weaken a tie, undo a shirt collar, provide inflow of fresh air. Splashing in a face of the patient cold water and bringing liquid ammonia to a nose, try to cause reflex excitement of the vascular and respiratory centers. At heavy HELL if the listed above actions did not conceive success, introduction of simpatikotonik is shown to a syncope with considerable falling (ephedrine, a fenilefrin). At arrhythmia antiaritmik are recommended, at cardiac arrest — introduction of atropine and indirect massage of heart.
Treatment of patients with faints
Therapeutic tactics at patients with a syncope to be divided into the undifferentiated and differentiated treatment. Undifferentiated approach is the general for all types of sinkopalny states and is especially urgent at unspecified genesis of a faint. Its main directions are: reduction of the threshold of neurovascular excitability, increase in level of vegetative stability, achievement of a condition of mental steadiness. As medicines of the 1st row in treatment of faints b-adrenoblokatory act (, ). At existence of contraindications apply ephedrine to purpose of b-adrenoblokatorov, . Vagolitik belong to medicines of the 2nd row (, ). Purpose of vazokonstriktor (an etafedrin, a midodrin), serotonin capture inhibitors is possible (methylphenidate, a sertralin). In the combined treatment use various sedative medicines (valerian root extract, extract of mint lemon and a peppermint, ergotamine, , belladonna extract, phenobarbital), sometimes — tranquilizers (oxazepam, to medazepa, fenazepa).
The differentiated therapy of a faint is chosen according to its type and clinical features. So, therapy of a faint at a syndrome of a carotid sine is based on application simpato-and holinolitik. In hard cases it is shown a surgical denervation of a sine. The basic in treatment of the faint connected with trigeminal or yazykoglotochny neuralgia is application of antikonvulsant (carbamazepine). The Vazovagalny faint to be treated mainly within undifferentiated therapy.
Repeating orthostatic to a syncope demand the actions directed to restriction of the volume of blood which is deposited in a lower body upon transition to vertical position. For achievement of a peripheral vazokonstriktion appoint dihydroergotamine and a-adrenomimetiki, for blocking of a vazodilyatation of peripheral vessels — propranolol. Patients with a cardiogenic faint are supervised by the cardiologist. If necessary the issue of implantation of a kardiovertera-defibrillator is resolved.
It should be noted that in all cases to a syncope treatment of patients surely includes therapy of the accompanying and causal diseases.