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CLINICAL PHYSIOLOGY OF THE NOSE AND NANOSAXIS

The nose and its paranasal sinuses, being the upper part of the respiratory tract, play an important role in the interaction of the body with the environment, while performing a number of interrelated physiological functions. The following nasal functions are distinguished: 1) respiratory, 2) protective, 3) resonator (speech) and 4) olfactory. In addition, the nose, as an important element in the formation of a single ensemble of the face, is endowed with a cosmetic function, or, according to V.I. Voyachek, a function of face well-being.

Respiratory function is the main, and its violation affects the functional state of other organs and systems. Reflexes from the nasal mucosa play an important role in the regulation and maintenance of normal functioning of the whole organism. Turning off nasal breathing or the presence of pathological processes in the nasal cavity and paranasal sinuses can lead to the development of various pathological conditions.

Normally, the air stream entering the nose forms an upward convex arch with sharp bends in the anterior part of the nasal cavity and a relatively gentle descent to the choanae. Rising vertically to the front end of the middle nasal concha, it is divided into two streams, one of which is directed to the nasopharynx along the middle nasal passage, and the other along the upper surface of the middle nasal concha. At the upper edge of the choan these flows are connected (Fig. 2.2.1, a). Inhaled air flow flows around the nasal concha and passes more medially, closer to the nasal septum. When inhaling, dissecting the posterior ends of the nasal conchs hanging over the choan, it is distributed laterally. Due to this, during exhalation, part of the air enters the olfactory gap, as well as into the paranasal sinuses, providing ventilation with humidified, warmed and purified air (Sagalovich B.M., 1967).

The degree of steepness of the air stream in the nasal cavity is associated with the angle formed by the upper lip and the free part of the nasal septum in the region of its vestibule (Undrits V.F., 1941). Therefore, the more this angle approaches the sharp, the steeper the air stream. On the contrary, when the aforementioned angle approaches a dull one, the air flow path forms a more gentle arc in the nasal cavity.

The formation of a stream of inhaled air is greatly influenced by the curvature of the nasal septum and the condition of the nasal concha. The normal, vertical direction of the inhaled air is significantly disturbed, especially when the nasal septum is curved in its upper and middle sections, which should be taken into account when correcting septum surgery.

Deformation and an increase in the size of the nasal concha (false or true hypertrophy) can cause not only excessive turbulence of the air stream, but also a complete cessation of nasal breathing.

Removal of nasal concha, incl. and insufficiently substantiated excessive conchotomy also leads not only to the development of atrophic processes in the nasal cavity, but also to a significant violation of nasal breathing. So, in the absence of a lower nasal concha, most of the air stream, separating from the main stream at the front end of the middle nasal concha, makes turbulent turbulences in the direction of the bottom of the nasal cavity and only then mixes with the main stream, with which it reaches the choan (Fig. 2.2. 1, b). Removal of one middle nasal concha is accompanied by smaller changes during the passage of air in the nasal cavity. However, with the simultaneous removal of the middle and lower nasal concha, there is a significant disruption in the course of the respiratory flow. In this case, only a small part of the main flow is directed arcuately upward. The bulk of the inhaled air passes along the bottom of the nasal cavity, forming significant turbulence (Fig. 2.2.1, c). It is worth adding that in the described options, patients constantly feel discomfort when breathing.

The protective function of the nose is carried out by various mechanisms and consists in warming, moisturizing, cleaning (dedusting) air from aerosol impurities and disinfecting it from pathogens. Of great importance in the implementation of the protective function of the nose are reflex reactions that occur in response to irritation of the mucous membrane by inhaled gaseous substances and aerosol impurities and manifest themselves in respiratory arrest, sneezing and lacrimation. The protective reflexes of stopping nasal breathing and sneezing in response to the entry of harmful gases into the nasal cavity were studied in detail at the end of the 1920s by K. L. Khilov. The research results that determined the mechanisms of these nose reflexes have not lost their relevance at the present time.

Protective reflexes of respiratory arrest upon inhalation of air containing life-threatening chemicals (0B, chloroform, ether, toluene, etc.) are carried out according to K. L. Khilov as follows: irritation of the sensory endings of the trigeminal nerve occurs, along the afferent fiber, the irritation is transmitted to intermediate neuron located in the medulla oblongata, and then the pulse is switched to the centers of the diaphragmatic and motor nerves, which are responsible for the contraction of the chest and abdominal press. According to these centrifugal paths, primary irritation of the trigeminal nerve causes respiratory arrest. This reflex path is confirmed by the following experiment. A tracheotomy cannula is inserted into the trachea to the rabbit, a glass tube curved at an angle is inserted above it, which, having passed the larynx and the oral part of the pharynx, is fixed in the nasopharyngeal space, the animal’s mouth is sutured with silk ligature and sealed with cotton wool soaked with collodion, the nasopharyngeal cannula is connected to the bellows using rubber tube, tracheotomy - with the Marey capsule, the writing pen of which is in contact with the kimograph tape. Below the pen, a time stamp and an indicator of the beginning and end of the experiment are set. A glass of cotton wool soaked in toluene is attached to the face of the animal (Fig. 2.2.2). When bellows are pushed apart, air saturated with toluene vapor enters only the nasal cavity. In this case, respiratory arrest occurs. This reflex cannot be obtained after transection of the Gasser node, which confirms the leading importance of the trigeminal nerve in the arc of the protective reflex.

In the presence of life-threatening chemicals, in addition to changes in breathing, there is also a violation of cardiovascular activity, manifested in an increase in blood pressure and a change in heart rate. However, this reflex is not the result of the direct action of a chemical on the nasal mucosa, but is caused by a change in breathing, in particular, a slowdown in rhythm or its stop. Proof of this is oo, that on cured animals, as well as during artificial rhythmic breathing, harmful chemicals no longer have an effect on cardiovascular activity.

The development of the given experience in terms of studying the role of sympathetic innervation in protective respiratory arrest has found interesting data confirming EA Orbeli's theory of the adaptive function of the sympathetic nervous system. So, if for a long period of time through the nose to conduct vapors of toluene or other harmful gas to the body, then at first breathing stops. Subsequently, the adaptation of the sensory endings of the trigeminal nerve in the animal develops and, despite continued irritation with harmful gas, normal breathing is restored again. During this period, if you produce electrical stimulation of the cervical sympathetic nerve, breathing stops again. The data from this experiment suggest that sympathetic innervation prepares the somatic (through the ends of the trigeminal nerve) for the normal fulfillment of its protective function. It should be noted that this adaptive function of the sympathetic innervation is autonomous, since it does not appear during anesthesia of the animal.

Another no less pronounced protective nasal reflex is sneezing. This reflex has several periods: 1) hidden, 2) preparatory, consisting in closing the glottis and contracting the soft palate, 3) the actual act of sneezing, expressed by violent expiration and the sound typical of sneezing, and 4) sequential - in the form of relaxation involved in sneezing muscles. Sneezing, as well as respiratory arrest, occurs as a result of irritation of the trigeminal nerve endings with coarser suspended particles contained in a stream of air. Comparing this reflex with protective respiratory arrest, we can say that if the latter is a warning reaction that signals the content of harmful substances in the air, then sneezing should be called a performing reflex, i.e. eliminating this irritant. This co-occurrence of both reflexes is clearly found in the experiment with inhalation of toluene.

Air is heated due to heat from a large surface of the mucous membrane of the walls of the nose, and the cavernous tissue of the nasal concha. The latter are a complex vascular apparatus that acts as calorifiers, capable of quickly responding to changes in temperature and humidity of the inhaled air, significantly increasing the volume of the nasal concha and the blood flow velocity. The warming of the air also contributes to the slowdown of its movement in the nasal cavity itself after passing through the narrowness of its vestibule.

Humidification of the air in the nasal cavity occurs due to saturation with moisture obtained from the surface of the mucous membrane.

Purification (dust removal) of air is provided by several mechanisms. Large particles of dust are delayed by the hairs of the vestibule of the nose (vibrissae).
Smaller dust (aerosol) particles, together with microbial bodies, are deposited on the mucous membrane covered with mucous secretions. In the mechanical removal of fine dust particles, germs and viruses, the mucociliary apparatus of the mucous membrane, which was discussed above, plays an important role.

The continuous process of self-cleaning of the nasal cavity and other airways, carried out by ciliated epithelium, is the main part of the first line of defense of the nasal mucosa. It has been established that up to 60% of viable microorganisms settle on the surface of the nasal mucosa. The normal functioning of the mucociliary apparatus minimizes the risk of colony formation from individual bacteria and the development of the inflammatory process. Both mucin of mucus itself (Spengler A.E., 1912) and bactericidal substances contained in mucus (lysozyme and others) that enter the nasal cavity along with tear fluid contribute to the disinfection (sterilization) of inhaled air. In the sterilization of inhaled air, the absorption abilities of the histiocytic elements of the mucous membrane, phagocytic microbial cells also play a role (L. Dainiak, 1994).

In the protective functions of the nose, the paranasal sinuses also play a role. According to C.3 Piskunov (1997), they can be considered as a system of reserve anatomical formations designed to protect the body, primarily the contents of the orbit and cranial cavity from the effects of various adverse factors contained in the air. In the case when specific and non-specific factors of protection of the nasal mucosa that form the first line of defense are unable to cope with the infectious pathogen that caused the inflammatory process in the nasal cavity, the sinuses of the ethmoid bone forming the second line of defense are included in the fight. It is no accident that a child is born with an already formed system of air-holes in the trellised labyrinth. The later developing large paranasal sinuses form the third line of defense, designed to limit and eliminate the inflammatory process directed towards the vital formations of the skull and orbit.

The resonant (speech) function of the nose is ensured by the presence of airways (the nasal cavity itself and the paranasal sinuses). In this case, the air cavities, resonating, amplify various tones of the voice and determine to a large extent its timbre. So, it is believed that low tones are resonated by large-volume air cavities (maxillary and frontal sinuses), and high ones by small cavities (ethmoid labyrinth cells, sphenoid sinus). Considering that the volume of the nasal cavity and sinuses is different for different people, the amplification and, consequently, the color of the sound (voice timbre) are also different. That is why in some countries (Italy) in the passports of citizens in the old days a voice timbre was also noted as one of the distinguishing features of an individual (K.L. Khilov, 1960).

The involvement of the nose and paranasal sinuses in speech function becomes noticeable when pronouncing nasal consonants. In this case, during the phonation, the soft sky hangs, the nose from the side of the choan becomes open. As a result, the sounds of speech acquire a "nasal sound." With an excessively large communication of the nose with the pharynx or, conversely, with nasal congestion, all phonemes of the nose acquire a nasal timbre. As a result, the so-called open (with paralysis of the soft palate or defect of the hard palate) nasal - rhinolalia aperta, and the so-called closed (with rhinitis, nasal polyps) nasal - rhinolalia clansa.

The olfactory function of the nose is carried out due to the presence of a specific olfactory analyzer, the morphological description of which was given above.

Functionally, the olfactory analyzer, like the taste, refers to the organs of chemical sensation. Adequate stimuli for it are odorous molecules called odorivectors. Molecules of odorous substances have certain properties. Among them - the ability to spread in the air in the form of gases and adsorb on surrounding objects, easy solubility in water and especially in fats. Molecules of odorous substances have incompletely saturated atomic bonds and carry a positive charge. The molecular weight of odorous substances ranges from 17 (ammonia) to 300 (alkaloids).

Until now, however, there is no universally accepted classification of odorous substances. The initial elements that make up those for other smells, like the elements forming the spectrum of white light, have not been established. However, it is known that individuals do not smell certain odors. They are called “olfactory color blind”. This, according to a number of scientists, allows us to hope for the possibility of establishing the initial elements of odors in identifying people with different options for "olfactory color blindness."

Adsorbing on the surface of the olfactory receptor, odorous molecules come into direct contact with the microvilli located on the club-shaped thickenings of the olfactory cells. The penetration of odorivectors into the microvill cytoplasm leads to the appearance of a receptor potential. Caused irritation spreads along the olfactory nerve pathways to the subcortical and cortical centers.

The sense of smell plays a big role in the life of humans and animals. According to the severity of smell, the whole animal world is divided into three groups: anosmatics (whales, dolphins), microsmatics (bats, primates, humans) and macromatics (predators, ungulates, rodents).

Animals need olfaction to search for food, have a sexual partner, and detect enemies. It is a kind of "animal language", providing mutual communication of individuals, and gives them extensive information about the events of the world, not always available to the organs of vision and hearing.

Dogs have an exceptional sense of smell. It has been established that dogs are especially sensitive to the smells of certain fatty acids - butyric, caprylic, valerianic, which apparently have important biological significance for them. A German shepherd, for example, is able to get an olfactory sensation from just one molecule of butyric acid.

The effect of olfaction on the fiction of the genital organs is evidenced by studies conducted on rodents. So, in mice, the smell of a “foreign” male can interrupt the pregnancy of the female. The destruction of the olfactory receptor leads to a delay in the ovarian cycle, suppresses the maternal instinct of females and dramatically reduces the sexual activity of male rats and hamsters (Bronstein A.A., 1977). The olfactory organ plays a significant role in human life, although it, like other primates, refers to micromatics. The sense of smell allows a person to determine the presence of harmful impurities in the inhaled air, helps to navigate in the environment. Through olfaction, a person determines the quality of food, receives a feeling of pleasure or disgust.

The olfactory analyzer is characterized by adaptation, which manifests itself as a temporary loss of sensitivity to various odors, as well as readaptation, i.e. restoration of sensitivity to odors. Adaptation and readaptation takes a few minutes. This ability of the olfactory analyzer to adapt complicates the conduct of quantitative methods for the study of smell.

If the odors are extremely long, especially sharp, the adaptation process can be replaced by fatigue of the analyzer. Маскировка запахов выражается в том, что один запах может заглушать другой. При смешивании запахов возможна их нейтрализация, когда пропадает ощущение смешиваемых запахов.

Обонятельный рецептор способен также к консонансу и диссонансу запахов. Так, пахучие вещества, обладающие каждый в отдельности неприятным запахом, в сочетании могут производить приятное ощущение (консонанс). Наоборот, два отдельно приятно пахнущих вещества в совокупности могут вызвать ощущение неприятного запаха (диссонанс).

Вкусовая роль обоняния зависит от проникновения через носоглотку в полость носа пищевых запахов, способных вызвать раздражение обонятельного рецептора. Это обстоятельство играет важную роль при приеме пищи, т.к. при нарушении обоняния пища становится безвкусной, нарушается аппетит.

На остроту обоняния оказывает влияние состояние окружающей среды (атмосферное давление, температура, влажность воздуха), а также общее состояние человека. Повышение остроты обоняния (гиперосмия) наблюдается при эмоциональном возбуждении, при приеме препаратов, возбуждающих ЦНС (в частности, стрихнин, фенамин).

Понижение остроты обоняния (гипосмия) может быть связано с общим утомлением и с патологией полости носа, когда обонятельнаяи щель закрывается набухшей слизистой оболочкой (острые, хронические гипертрофические и аллергические риниты) или при атрофии слизистой оболочки (атрофический ринит). Гипосмия часто встречается у курильщиков. Атрофия слизистой оболочки, наблюдаемая при озене, приводит к полной потере обоняния (аносмии). Аносмия может быть одним из осложнений респираторных вирусных заболеваний верхних дыхательных путей.

Патологические процессы в области проводящих путей и центрального представительства обонятельного анализатора (например, при объемных процессах лобной доли) могут сопровождаться гипо- и аносмией (обычно односторонней).

Извращение обонятельной чувствительности, обусловленное функциональным состоянием нервной системы, нередко наблюдается при беременности. Внезапное появление ощущения запахов, не связанных с нахождением пахучих веществ в окружающем воздухе (обонятельная аура), может возникать у эпилептиков как предвестник приступа заболевания.
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КЛИНИЧЕСКАЯ ФИЗИОЛОГИЯ НОСА И ОКОЛОНОСОВЫХ ПАЗУХ

  1. Clinical physiology of the nose and paranasal sinuses
    Distinguish between upper and lower respiratory tract. The nose and paranasal sinuses, pharynx with the oral cavity and larynx belong to the upper respiratory tract, the trachea, bronchi with bronchioles of the alveoli - to the lower. Normal for a person is breathing through the nose. The nose performs, in addition to the respiratory, protective, resonant and olfactory functions, and also participates in the regulation of the depth of breathing and lacrimation,
  2. КЛИНИЧЕСКАЯ АНАТОМИЯ И ФИЗИОЛОГИЯ НОСА И ОКОЛОНОСОВЫХ ПАЗУХ
    КЛИНИЧЕСКАЯ АНАТОМИЯ И ФИЗИОЛОГИЯ НОСА И ОКОЛОНОСОВЫХ
  3. КЛИНИЧЕСКАЯ АНАТОМИЯ НОСА И ОКОЛОНОСОВЫХ ПАЗУХ
    КЛИНИЧЕСКАЯ АНАТОМИЯ НОСА И ОКОЛОНОСОВЫХ
  4. TUMORS OF THE NOSE AND NANOPINASUS SINAS
    In the nasal cavity and paranasal sinuses, as in other ENT organs, there are benign and malignant neoplasms, very diverse in morphological structure and clinical manifestation. A distinct border is often impossible to draw with many benign and malignant tumors. Modern classifications of tumors, including the nose and paranasal sinuses, are bulky and
  5. МЕТОДЫ ИССЛЕДОВАНИЯ НОСА И ОКОЛОНОСОВЫХ ПАЗУХ
    Исследование носа и околоносовых пазух, после выявления жадоб и выяснения анамнеза, начинается с наружного осмотра и пальпации. При осмотре обращают внимание на состояние кожных покровов и мягких тканей, отсутствие или наличие дефектов, симметричность обеих половин лица, а также на форму наружного носа. Пальпация должна производиться осторожно. Мягкими движениями рук устанавливают наличие или
  6. Malignant tumors of the nose and paranasal sinuses
    Malignant diseases of this localization - cancer and isarcoma, as a rule, are primary. They are relatively rare, more often in middle-aged and elderly men. Most often, the primary malignant process affects the maxillary, then the ethmoid, frontal and sphenoid sinuses. Rarely, the nasal septum is the source of the malignant tumor. Malignancy
  7. Методы исследования носа и околоносовых пазух
    Производят о с м о т р наружного носа, мест проекции околоносовых пазух носа на лице. П а л ь п а ц и я наружного носа: указательные пальцы обеих рук располагаются вдоль спинки носа, легкими массирующими движениями ощупывают области корня, скатов, спинки и кончика носа. Пальпируют переднюю и нижнюю стенки лобных пазух, выясняя при этом ощущения больного. Большие пальцы обеих рук
  8. Surgery for diseases of the nose and paranasal sinuses
    The most common operations for diseases of the nose and paranasal sinuses include polypectomy, endoscopic interventions in the paranasal sinuses, opening the maxillary sinus (Caldwell-Luc operation), rhinoplasty, septoplasty. Preoperative period Patients often have marked nasal breathing disorders due to polyps, nasal curvature
  9. Инородные тела носа и околоносовых пазух
    Наиболее часто инородные тела встречаются у детей, имеющих привычку закладывать в нос себе или своим доверчивым сверстникам различные предметы (бусы, пуговицы, камешки, монеты, ягодные косточки, семечки и другие мелкие предметы). У взрослых инородные тела попадают в нос при случайных обстоятельствах (например, во время сна на сеновале при дыхании может быть втянут в нос кусочек соломы). More
  10. Перелом костей носа и околоносовых пазух
    Д - ка: Определяется асимметрия лица в виде деформации наружного носа, западение лицевых стенок пазух, повреждение кожных покровов, боль при пальпации (иногда вместе с этим — хруст, крепитация костных обломков и воздуха в подкожных тканях), отек, гематома век и обычно кровотечение из носа. В зависимости от глубины повреждения переломы могут быть изолированными, либо сочетаться с травмой головы
  11. Микроэндоскопические методы хирургического вмешательства в полости носа и околоносовых пазухах
    Существует ряд вариантов эндоназальных эндоскопических микроопераций, однако все методики можно объединить в две основные разновидности — это классические методики по Мессерклингеру и по Виганду, они предназначены для восстановления естественных вентиляционно-дренажных путей, с наименьшими изменениями анатомических структур и максимальным щажением слизистой оболочки. Наиболее широко
  12. ЗАБОЛЕВАНИЯ НОСА И ОКОЛОНОСОВЫХ ПАЗУХ, ГЛОТКИ, ГОРТАНИ И УХА
    Верхние дыхательные пути (нос, околоносовые пазухи, глотка и гортань) выполняют важнейшие жизнеобеспечивающие функции, подробное описание которых приведено в части I. Следующая часть посвящена болезням этих органов. На основании функциональной значимости в клинике каждого из органов — рефлекторых, гуморальных и других связей этих органов с организмом вцелом можно сделать заключение о
  13. ЗАБОЛЕВАНИЯ НОСА И ОКОЛОНОСОВЫХ ПАЗУХ
    ЗАБОЛЕВАНИЯ НОСА И ОКОЛОНОСОВЫХ
  14. Лечение повреждений носа и околоносовых пазух на этапах эвакуации
    Самопомощь и взаимопомощь. Осуществляется в порядке самопомощи, взаимопомощи санитаром или санинструктором. При ушибах, сопровождающихся носовым кровотечением, следует попытаться остановить кровотечение прижатием крыльев носа к носовой перегородке. На область наружного носа прикладывается снег, лед или ткань, смоченная холодной водой. При ссадинах на коже или поверхностных ранениях накладывают
  15. Clinical anatomy of the paranasal sinuses
    The paranasal sinuses are located around the nasal cavity and communicate with it (Fig. 1.8). Only four pairs of airways: sinuses, maxillary labyrinth cells, frontal and sphenoid. There are anterior (maxillary, frontal, anterior and middle cells of the ethmoid bone) and posterior (sphenoid and posterior cells of the ethmoid bone) sinuses. Such a unit is convenient because pathology
  16. Anatomy of the paranasal sinuses
    The paranasal sinuses, sinus paranasalis, are located in the bones of the facial and brain skulls and communicate with the nasal cavity. They are formed as a result of the ingrowth of the mucous membrane of the middle nasal passage into the spongy bone tissue. In fig. 2.1.4 presents a diagram of the development of the paranasal sinuses in the age aspect. Phylogenetically paranasal sinuses are derivatives of the ethmoid labyrinth
  17. Diseases of the paranasal sinuses
    Inflammatory diseases of the paranasal sinuses account for 25-30% of the stationary pathology of the LOP organs. Most often, inflammation occurs in the maxillary (maxillary) sinus (sinusitis). This is due to the fact that evacuation of the contents from the sinus is difficult due to the location of the anastomosis with the nasal cavity in the upper third of its medial wall, as well as the fact that the inflammation of the roots of the four rear
  18. Injuries to the paranasal sinuses
    In adults and children, the frontal sinuses are most often damaged, then the maxillary sinuses, the ethmoid labyrinth and very rarely the sphenoid sinus. Usually, a trauma to a sinus is combined with damage to other parts of the facial skeleton, cranial cavity, and eyes. A mechanical or gunshot wound to the frontal sinus is often accompanied by damage to the anterior lobe of the brain, ethmoid labyrinth, sieve
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