"lungs experience during breathing. The respiratory tract is divided into the upper airways and lower airways. The upper airways or upper respiratory tract includes the nose and nasal passages, paranasal sinuses, the pharynx, and the portion of the larynx above the vocal folds (cords). The lower airways or lower respiratory tract includes the portion of the larynx below the vocal folds, trachea, bronchi and bronchioles. The lungs can be included in the lower respiratory tract or as separate entity and include the respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli. The respiratory tract can also be divided into a conducting"
"Eustachian tube The Eustachian tube, also known as the auditory tube or pharyngotympanic tube, is a tube that links the nasopharynx to the middle ear. It is a part of the middle ear. In adult humans the Eustachian tube is approximately long and in diameter. It is named after the sixteenth-century Italian anatomist Bartolomeo Eustachi. In humans and other land animals the middle ear (like the ear canal) is normally filled with air. Unlike the open ear canal, however, the air of the middle ear is not in direct contact with the atmosphere outside the body. The Eustachian tube connects"
"is damaged. Epistaxis (nosebleed) is a very common presentation to veterinary surgeons and this may often be fatal unless a balloon catheter can be placed in time to suppress bleeding. Eustachian tube The Eustachian tube, also known as the auditory tube or pharyngotympanic tube, is a tube that links the nasopharynx to the middle ear. It is a part of the middle ear. In adult humans the Eustachian tube is approximately long and in diameter. It is named after the sixteenth-century Italian anatomist Bartolomeo Eustachi. In humans and other land animals the middle ear (like the ear canal) is normally"
"palate and lies above the oral cavity. The adenoids, also known as the pharyngeal tonsils, are lymphoid tissue structures located in the posterior wall of the nasopharynx. Waldeyer's tonsillar ring is an annular arrangement of lymphoid tissue in both the nasopharynx and oropharynx. The nasopharynx is lined by respiratory epithelium that is pseudostratified, columnar, and ciliated. Polyps or mucus can obstruct the nasopharynx, as can congestion due to an upper respiratory infection. The auditory tube, which connect the middle ear to the pharynx, opens into the nasopharynx at the pharyngeal opening of the auditory tube. The opening and closing of"
"the great wing of the sphenoid; this groove ends opposite the middle of the medial pterygoid plate. The cartilaginous and bony portions of the tube are not in the same plane, the former inclining downward a little more than the latter. The diameter of the tube is not uniform throughout, being greatest at the pharyngeal opening, least at the junction of the bony and cartilaginous portions, and again increased toward the tympanic cavity; the narrowest part of the tube is termed the isthmus. The position and relations of the pharyngeal opening are described with the nasal part of the pharynx."
"the pharyngeal plexus of the vagus nerve. Muscles in the pharynx push the food into the esophagus. The pharynx joins the esophagus at the oesophageal inlet which is located behind the cricoid cartilage. The esophagus, commonly known as the foodpipe or gullet, consists of a muscular tube through which food passes from the pharynx to the stomach. The esophagus is continuous with the laryngopharynx. It passes through the posterior mediastinum in the thorax and enters the stomach through a hole in the thoracic diaphragm—the esophageal hiatus, at the level of the tenth thoracic vertebra (T10). Its length averages 25 cm,"
"Palatovaginal canal The palatovaginal canal (also pharyngeal canal) is a canal between the sphenoid bone and the palatine bone that connects the nasopharynx with the pterygopalatine fossa. An inconstant vomerovaginal canal may lie between the ala of the vomer and the vaginal process of the sphenoid bone, medial to the palatovaginal canal, and lead into the anterior end of the palatovaginal canal. It transmits the pharyngeal branch of the third part of the maxillary artery. The palatovaginal canal contains the pharyngeal nerve from the pterygopalatine ganglion and the pharyngeal branch of the maxillary artery. The pharyngeal nerve conveys sensory information"
"Laryngeal tube The laryngeal tube (also known as the King LT) is an airway management device designed as an alternative to other airway management techniques such as mask ventilation, laryngeal mask airway, and tracheal intubation. This device can be inserted blindly through the oropharynx into the hypopharynx to create an airway during anaesthesia and cardiopulmonary resuscitation so as to enable mechanical ventilation of the lungs. Various studies have shown that insertion and use of the standard tracheal tube is easy, providing a clear airway in the majority of cases. Comparative studies indicate that the standard laryngeal tube is generally as"
"an alveolus . The upper respiratory tract, can refer to the parts of the respiratory system lying above the sternal angle (outside of the thorax), above the vocal folds, or above the cricoid cartilage. The larynx is sometimes included in both the upper and lower airways. The larynx is also called the voice box and has the associated cartilage that produces sound. The tract consists of the nasal cavity and paranasal sinuses, the pharynx (nasopharynx, oropharynx and laryngopharynx) and sometimes includes the larynx. The lower respiratory tract or lower airway is derived from the developing foregut and consists of the"
"The oropharynx, at the back of the mouth, forms a circle and includes the base of the tongue (posterior third) below, the tonsils on each side, and the soft palate above, together with the walls of the pharynx, including the anterior epiglottis, epiglottic valleculae and branchial cleft at its base. The oropharynx is one of three divisions of the interior of the pharynx based on their relation to adjacent structures (nasal pharynx (nasopharynx), oral pharynx (oropharynx) and laryngeal pharynx (laryngopharynx - also referred to as the hypopharynx), from top to bottom). The pharynx is a semicircular fibromuscular tube joining the"
"thus bringing the air into close contact with the blood. These air sacs communicate with the external environment via a system of airways, or hollow tubes, of which the largest is the trachea, which branches in the middle of the chest into the two main bronchi. These enter the lungs where they branch into progressively narrower secondary and tertiary bronchi that branch into numerous smaller tubes, the bronchioles. In birds the bronchioles are termed parabronchi. It is the bronchioles, or parabronchi that generally open into the microscopic alveoli in mammals and atria in birds. Air has to be pumped from"
"set off an allergic reaction, causing swelling of the bronchial tubes; as a result, the air passage will swell up, or close up completely. Respiratory tract In humans, the respiratory tract is the part of the anatomy of the respiratory system involved with the process of respiration. Air is breathed in through the nose or the mouth. In the nasal cavity, a layer of mucous membrane acts as a filter and traps pollutants and other harmful substances found in the air. Next, air moves into the pharynx, a passage that contains the intersection between the esophagus and the larynx. The"
"Respiratory tract In humans, the respiratory tract is the part of the anatomy of the respiratory system involved with the process of respiration. Air is breathed in through the nose or the mouth. In the nasal cavity, a layer of mucous membrane acts as a filter and traps pollutants and other harmful substances found in the air. Next, air moves into the pharynx, a passage that contains the intersection between the esophagus and the larynx. The opening of the larynx has a special flap of cartilage, the epiglottis, that opens to allow air to pass through but closes to prevent"
"nasal cavity. When producing nasal consonants (such as ""m"", ""n"", and ""ng""), the soft palate remains relaxed, thereby enabling the air to go through the nose. The Eustachian tube, which opens near the velopharyngeal sphincter, connects the middle ear and nasal pharynx. Normally, the tube ensures aeration and drainage (of secretions) of the middle ear. Narrow and closed at rest, it opens during swallowing and yawning, controlled by the tensor veli palatini and the levator veli palatini (muscles of the soft palate). Children with a cleft palate have difficulties controlling these muscles and thus are unable to open the Eustachian"
"air inhaled. The trachea is the tube which carries air from the oral cavity and into the lungs, and is about 75–80 cm in length in the adult. It is held permanently open by 50-60 ""C""-shaped rings of cartilage, 5–6 cm in diameter. At the bifurcation of the trachea, there are two bronchi, the right of which is slightly larger in size. The bronchi then branch into smaller bronchioles, which in turn branch off into smaller bronchioles until they reach the alveoli (which absorb oxygen from the air and releases the carbon dioxide waste). The bronchi and bronchioles are all"
"the tube, while its base lies directly under the mucous membrane of the nasal part of the pharynx, where it forms an elevation, the torus tubarius or cushion, behind the pharyngeal opening of the auditory tube. The upper edge of the cartilage is curled upon itself, being bent laterally so as to present on transverse section the appearance of a hook; a groove or furrow is thus produced, which is open below and laterally, and this part of the canal is completed by fibrous membrane. The cartilage lies in a groove between the petrous part of the temporal bone and"
"the pharynx. In humans, the tongue has an almost circular sagittal (midline) contour, much of it lying vertically down an extended pharynx, where it is attached to a hyoid bone in a lowered position. Partly as a result of this, the horizontal (inside-the-mouth) and vertical (down-the-throat) tubes forming the supralaryngeal vocal tract (SVT) are almost equal in length (whereas in other species, the vertical section is shorter). As we move our jaws up and down, the tongue can vary the cross-sectional area of each tube independently by about 10:1, altering formant frequencies accordingly. That the tubes are joined at a"
"conducting zone of the respiratory system and also a part of the digestive system. It is the part of the throat immediately behind the nasal cavity at the back of the mouth and above the esophagus and larynx. The pharynx is made up of three parts. The lower two parts—the oropharynx and the laryngopharynx are involved in the digestive system. The laryngopharynx connects to the esophagus and it serves as a passageway for both air and food. Air enters the larynx anteriorly but anything swallowed has priority and the passage of air is temporarily blocked. The pharynx is innervated by"
"pouches fuse to form a median septum. The guttural pouches connect the middle ear to the pharynx. The opening into the pharynx is called the nasopharyngeal ostium, which is composed of the pharyngeal wall laterally and a fibrocartilaginous fold medially. This opening leads to a short soft tissue passageway into the respective guttural pouch. The openings are located rostrally to enable drainage of mucous when the head is lowered and prevent fluid build-up. The ""plica salpingopharyngea,"" a mucosal fold at the caudal portion of the Eustachian tube, forms an uninterrupted channel between the medial lamina of the Eustachian tube and"
"sac of variable size called the appendix of the laryngeal ventricle. The appendix (also called the laryngeal saccule, pouch or Hilton's pouch) extends vertically from the laryngeal ventricle. It runs between the vestibular fold, thyroarytenoid muscle, and thyroid cartilage, and is conical, bending slightly backward. It is covered in roughly seventy mucous glands. The muscles surrounding the appendix compress it until mucus is secreted to lubricate the vocal folds. Laryngeal ventricle The laryngeal ventricle, (also called the ventricle of the larynx, laryngeal sinus, or Morgagni's sinus) is a fusiform fossa, situated between the vestibular and vocal folds on either side,"
"Laryngeal ventricle The laryngeal ventricle, (also called the ventricle of the larynx, laryngeal sinus, or Morgagni's sinus) is a fusiform fossa, situated between the vestibular and vocal folds on either side, and extending nearly their entire length. There is also a sinus of Morgagni in the pharynx. The fossa is bounded, above, by the free crescentic edge of the vestibular ligament; below, by the straight margin of the vocal fold and laterally, by the mucous membrane covering the corresponding thyroarytenoid muscle. The anterior part of the ventricle leads up by a narrow opening into a pouch-like diverticulum, a mucous membranous"
"part of the larynx above the vocal folds. The lower tract (Fig. 2.) includes the lower part of the larynx, the trachea, bronchi, bronchioles and the alveoli. The branching airways of the lower tract are often described as the respiratory tree or tracheobronchial tree (Fig. 2). The intervals between successive branch points along the various branches of ""tree"" are often referred to as branching ""generations"", of which there are, in the adult human about 23. The earlier generations (approximately generations 0–16), consisting of the trachea and the bronchi, as well as the larger bronchioles which simply act as air conduits,"
"the auditory tubes serves to equalize the barometric pressure in the middle ear with that of the ambient atmosphere. The anterior aspect of the nasopharynx communicates through the choanae with the nasal cavities. On its lateral wall is the pharyngeal opening of the auditory tube, somewhat triangular in shape, and bounded behind by a firm prominence, the torus tubarius or cushion, caused by the medial end of the cartilage of the tube which elevates the mucous membrane. Two folds arise from the cartilaginous opening: The oropharynx lies behind the oral cavity, extending from the uvula to the level of the"
"or tube), the infant is fitted with a blunt-tipped length of surgical tubing (or an endotracheal tube fitted to the child), which is placed under direct visualization with a laryngoscope, being inserted into the nose and down the pharynx (or throat), ending just above the vocal cords. Surgical threads fitted through holes in the outside end of the tube are attached to the cheek with a special skin-like adhesive material called 'stomahesive', which is also wrapped around the outside end of the tube (but not over the opening at the end) to keep the tube in place. This tube or"
"folds. When the tracheoesophageal folds fuse in the midline to form the tracheoesophageal septum, the foregut is divided into trachea ventrally and the esophagus dorsally. The tube is lined by endoderm from which the epithelial lining of the respiratory tract is developed. The cephalic part of the tube becomes the larynx, and its next succeeding part the trachea, while from its caudal end a respiratory diverticulum appears as the lung bud. The lung bud branches into two lateral outgrowths known as the bronchial buds, one on each side of the trachea. The right and left bronchial buds branch into main"
"food from moving into the airway. From the larynx, air moves into the trachea and down to the intersection that branches to form the right and left primary (main) bronchi. Each of these bronchi branch into secondary (lobar) bronchi that branch into tertiary (segmental) bronchi that branch into smaller airways called bronchioles that eventually connect with tiny specialized structures called alveoli that function in gas exchange. The lungs which are located in the thoracic cavity, are protected from physical damage by the rib cage. At the base of the lungs is a sheet of skeletal muscle called the diaphragm. The"
"immediately behind the nasal cavity, behind the mouth and above the esophagus and larynx. The human pharynx is conventionally divided into three sections: the nasopharynx, oropharynx, and laryngopharynx. It is also important in vocalization. In humans, two sets of pharyngeal muscles form the pharynx and determine the shape of its lumen. They are arranged as an inner layer of longitudinal muscles and an outer circular layer. The upper portion of the pharynx, the nasopharynx, extends from the base of the skull to the upper surface of the soft palate. It includes the space between the internal nares and the soft"
"The mucous membrane of the tube is continuous in front with that of the nasal part of the pharynx, and behind with that of the tympanic cavity; it is covered with ciliated pseudostratified columnar epithelia and is thin in the osseous portion, while in the cartilaginous portion it contains many mucous glands and near the pharyngeal orifice a considerable amount of adenoid tissue, which has been named by Gerlach the tube tonsil. There are four muscles associated with the function of the Eustachian tube: The tube is opened during swallowing by contraction of the tensor veli palatini and levator veli"
"ill or anesthetized patients in order to perform mechanical positive pressure ventilation of the lungs and to prevent the possibility of aspiration or airway obstruction. The endotracheal tube has a fitting designed to be connected to a source of pressurized gas such as oxygen. At the other end is an orifice through which such gases are directed into the lungs and may also include a balloon (referred to as a cuff). The tip of the endotracheal tube is positioned above the carina (before the trachea divides to each lung) and sealed within the trachea so that the lungs can be"
"reasoning that if the respiratory tree is seen as a tube ending at the glottis and the objective is to connect this tube to an artificial airway, the most logical solution was to create a direct end-to-end junction. Existing airway devices clearly failed to form this junction; the face-mask sealed against the face, and the endotracheal tube penetrated too far so that the junction was created within the trachea, instead of at its beginning. Dr Brain wrote in his diary in May 1981, ""Better, use a loop fitting into the anatomical loop of space surrounding the larynx, with a projection"
"Laryngeal mask airway A laryngeal mask airway (LMA) — also known as laryngeal mask— is a medical device that keeps a patient's airway open during anaesthesia or unconsciousness. It is a type of supraglottic airway. A laryngeal mask is composed of an airway tube that connects to an elliptical mask with a cuff which is inserted through the patient's mouth, down the windpipe, and once deployed forms an airtight seal on top the glottis (unlike tracheal tubes which pass through the glottis) allowing a secure airway to be managed by a health care provider. They are most commonly used by"
"to this point as it extends towards the larynx. However, when tracheal deviation is present, the trachea will be displaced in the direction of less pressure. Meaning, that if one side of the chest cavity has an increase in pressure (such as in the case of a pneumothorax) the trachea will shift towards the opposing side. The trachea is the tube that carries air from the throat to the lungs. It is also commonly referred to as the windpipe. The trachea is one of the most important parts of the respiratory system and damage to the trachea can indicate a"
"video laryngoscope to identify the vocal cords and pass the tube between them into the trachea instead of into the esophagus. Other devices and techniques may be used alternatively. After the trachea has been intubated, a balloon cuff is typically inflated just above the far end of the tube to help secure it in place, to prevent leakage of respiratory gases, and to protect the tracheobronchial tree from receiving undesirable material such as stomach acid. The tube is then secured to the face or neck and connected to a T-piece, anesthesia breathing circuit, bag valve mask device, or a mechanical"