Nursing 7th Notes PDF

Respiratory System A. Taha Demirbas, Assis. Prof Anatomy  Breath represents life The first breath of a baby and the last gasp of a dying person are two of the most dramatic moments of human experience Why must we breathe? It comes down to the fact that most of our metabolism directly...

Respiratory System A. Taha Demirbas, Assis. Prof Anatomy  Breath represents life The first breath of a baby and the last gasp of a dying person are two of the most dramatic moments of human experience Why must we breathe? It comes down to the fact that most of our metabolism directly or indirectly requires ATP Most ATP synthesis requires oxygen and generates carbon dioxide—thus driving the need to breathe in order to supply the former and eliminate the latter The respiratory system consists essentially of tubes that deliver air to the lungs, where oxygen diffuses into the blood and carbon dioxide is removed from it  The respiratory system is an organ system specialized to provide oxygen to the blood and remove carbondioxide from it It has more diverse functions: Gas exhange Communication Olfaction Acid–base balance Blood pressure regulation Blood flow Expulsion of abdominal contents  The principal organs of the respiratory system are the nose, pharynx, larynx, trachea, bronchi, and lungs Within the lungs, air flows along a dead-end pathway consisting essentially of bronchi → bronchioles → alveoli During inspiration (inhaling), incoming air stops in the alveoli (millions of thin-walled, microscopic air sacs) and exchanges gases with the bloodstream across the alveolar wall; It flows back out during expiration (exhaling)  The conducting division of the respiratory system consists of those passages that serve only for airflow, essentially from the nostrils through the bronchioles No gases are exchanged with the blood in these passages because their walls are too thick to allow for sufficiently rapid gas diffusion The respiratory division consists of the alveoli and other distal gas-exchange regions The airway from the nose through the larynx is often called the upper respiratory tract And the regions from the trachea through the lungs compose the lower respiratory tract Nose (nasus) The nose has several functions: It warms, cleanses, and humidifies inhaled air It detects odors in the airstream It serves as a resonating chamber that amplifies the voice It extends from a pair of anterior openings called the nostrils, or nares (singular, naris), to a pair of posterior openings called the posterior nasal apertures or choanae  The facial part of the nose is shaped by bone and hyaline cartilage Its superior half is supported by a pair of small nasal bones medially and the maxillae laterally The inferior half is supported by the lateral and alar cartilages By palpating your own nose, you can easily find the boundary between the bone of the nasal bridge and the more flexible cartilage below  The nasal cavity begins with a small dilated chamber called the vestibule just inside each nostril The nasal cavity is divided into right and left halves called nasal fossae by a wall of bone and hyaline cartilage, the nasal septum There is not much space in the nasal cavity. Most of it is occupied by three bony scrolls covered by mucous membrane—the superior, middle, and inferior nasal conchae, or turbinates Beneath each concha is a narrow air passage called a meatus The narrowness of these passages and the turbulence produced by the conchae ensure that most air contacts the mucous membrane on its way through Throat (pharynx) The pharynx, or throat, is a muscular funnel extending about 13 cm from the choanae to the larynx It has three regions: Nasopharynx Oropharynx Laryngopharynx Larynx The larynx (“voice box”) is a cartilaginous chamber about 4 cm long Its primary function is to keep food and drink out of the airway, but it has the additional role of sound production (phonation) The superior opening of the larynx is guarded by a flap of tissue called the epiglottis (originally cartilage) During swallowing, extrinsic muscles of the larynx pull the larynx upward toward the epiglottis, the tongue pushes the epiglottis downward to meet it, and the epiglottis closes the airway and directs food and drink into the esophagus behind it  The framework of the larynx consists of nine cartilages The first three are solitary and relatively large The most superior one, the epiglottic cartilage, is a spoon-shaped supportive plate in the epiglottis The largest, the thyroid cartilage, is named for its shieldlike shape It broadly covers the anterior and lateral aspects of the larynx The “Adam’s apple” is an anterior peak of the thyroid cartilage called the laryngeal prominence Inferior to the thyroid cartilage is a ringlike cricoid cartilage Glottis The vocal cords and the opening between them are collectively called the glottis It is the name given to the space between two vocal cords This range widens during inspiration and narrows during phonation The tone and thickness of the sound are adjusted with various movements of the plica vocalis The pitch of the voice increases with stretching The force of expiration determines the loudness of the sound Trachea and Bronchi The trachea, or “windpipe,” is a tube about 12 cm long and 2.5 cm in diameter Lying anterior to the esophagus It is supported by 16 to 20 C-shaped rings of hyaline cartilage, some of which you can palpate between your larynx and sternum At the level of the sternal angle and the superior margin of vertebra T5, the trachea forks into right and left bronchi  The branching of the bronchi is as follows Bronchus principalis (primary bronchus) Bronchus lobaris (secondary bronchus) Bronchus segmentalis (tertiary bronchus) Bronchiolus terminalis Bronchiolus respiratorius Ductus alveolaris Saccus alveolaris Alveolus Lungs (pulmones) Apex It has three faces: Facies diaphragmatica Facies costalis Facies mediastinalis The formations entering and exiting the lung in the mediastinal faces form the radix (root) pulmonis The place where they enter the lung is called the hilum pulmonis Root of the lung The mediastinal surface exhibits a slit called the hilum through which the lung receives the main bronchus, blood vessels, lymphatic vessels, and nerves These structures constitute the root of the lung These are mainly; Pulmonary artery Pulmonary vein Bronchial artery and vein Main bronchi  On the medial surface, the left lung has an indentation called the cardiac impression where the heart presses against it The right lung has three lobes—superior, middle, and inferior A deep groove called the horizontal fissure separates the superior lobe from the middle lobe, and a similar groove called the oblique fissure separates the middle and inferior lobes The left lung has only a superior and inferior lobe and a single oblique fissure Pleura Pleura is a two-layered serous membrane that surrounds the lungs Pleura visceralis surrounds the lung tissue It enters between the fissures and forms lobes Pleura parietalis surrounds the pleura visceralis externally Covers the inner face of the cavitas thoracis Pleural cavity is a narrow potential space located between two layers of pleura It contains a serous fluid that prevents the friction of the two membranes