Name: pulmonary ventilation and breathing pressures
Uploaded: 2025-05-22T09:06:19.000Z
Duration: 1 min 24 s
Channel: JoVE

K12 Standards

ohios-learning-standards-and-model-curriculum

Ohio’s Learning Standards and Model Curriculum

9-12

Human Anatomy and Physiology

Absorption And Excretion

Respiratory System

Pulmonary Ventilation: Inhalation

Respiration is a rhythmic process of alternating inhalation and exhalation.
During quiet inhalation, the thoracic cavity expands due to a decrease in the gas pressure within the lungs, prompting air to flow in.
The diaphragm is the most important muscle for inhalation. It contracts and descends about 1 cm and flattens, thereby increasing the height of the thoracic cavity and creating a pressure difference of about 1 to 3 mm Hg.
The contraction of the external intercostal muscles lifts the rib cage and pulls the sternum upwards.
The ribs protrude outward, expanding the diameter of the thorax laterally and anteroposteriorly.
Although the thoracic dimensions change by only a few millimeters, it increases the thoracic volume by about 500 ml.
As the thoracic dimensions enlarge, the intrapulmonary volume increases, leading to a decrease in intrapulmonary pressure by about 1 mm Hg below atmospheric pressure.
Air flows into the lungs until the intrapulmonary pressure equals the atmospheric pressure. Concurrently, the intrapleural pressure falls to approximately -6 mm Hg relative to the atmospheric pressure.

longventilatie: inademing

Pulmonale ventilatie is een vitaal proces dat zorgt voor de uitwisseling van zuurstof en koolstofdioxide in de longen. Het verwijst naar de beweging van lucht in en uit de longen, waardoor het lichaam zuurstof kan verkrijgen en afvalkooldioxide kan verwijderen. In dit artikel zullen we de complexiteit van pulmonale ventilatie onderzoeken, inclusief de onderliggende principes, mechanismen en de wisselwerking van druk in het ademhalingssysteem.

De wet van Boyle wordt met name relevant bij het onderzoeken van ademhalingsvolumes en -drukken. In de context van pulmonale ventilatie zijn verschillende sleuteltermen essentieel om te begrijpen:

Teugvolume (TV) verwijst naar de hoeveelheid lucht die tijdens normale ademhaling wordt in- of uitgeademd zonder dat er bewuste inspanning nodig is.

Het inspiratoire reservevolume (IRV) is het maximale volume lucht dat geforceerd kan worden ingeademd, voorbij het teugvolume.

Expiratoir reservevolume (ERV): Het maximale volume lucht dat geforceerd kan worden uitgeademd voorbij het teugvolume.

Restvolume (RV): Het luchtvolume dat in de longen achterblijft na maximale uitademing. 
Deze ademhalingsvolumes dragen bij aan de berekening van belangrijke parameters, zoals de vitale capaciteit.

De vitale capaciteit (VC) is de som van het ademvolume, het inspiratoire reservevolume en het expiratoire reservevolume.

Bovendien is de relatie tussen ademhalingsvolumes en druk nauw met elkaar verbonden. Tijdens normale inademing (inademing) trekken het middenrif en de externe intercostale spieren samen, waardoor de borstholte uitzet. Deze uitzetting vergroot het longvolume, wat leidt tot een afname van de intrapulmonale druk, waardoor lucht van de atmosfeer naar de longen kan stromen.

De mechanica van inspiratie (inademing)

Inademing vindt plaats door een reeks onderling verbonden processen waarbij het middenrif, de intercostale spieren en de expansie van de borstholte betrokken zijn. Laten we elke stap uitsplitsen:

<ol>
	<li>Diafragmatische contractie: Tijdens normale inademing is de primaire spier die hierbij betrokken is het diafragma. Deze koepelvormige, bladachtige spier scheidt de borstholte (thoracale holte) van de buikholte. Wanneer we inademen, trekt het diafragma samen en wordt plat, waardoor het volume van de borstholte toeneemt. Deze actie creëert een negatieve intrapulmonale druk, waardoor lucht in de longen wordt getrokken.</li>
	<li>Intercostale spierbetrokkenheid: De intercostale spieren zijn een andere cruciale groep spieren die betrokken zijn bij inademing. Ze bevinden zich tussen de ribben en zijn verdeeld in externe en interne intercostale spieren.
	Externe intercostale spieren: Tijdens het inademen trekken deze spieren samen, waardoor de ribbenkast wordt opgetild en uitgezet. Deze beweging vergroot het volume van de borstholte verder, waardoor de luchtinname wordt verbeterd.

	Interne intercostale spieren: Deze spieren helpen bij diepe inademing en krachtige uitademing. Tijdens geforceerde inademing trekken de bovenste interne intercostale spieren samen, waardoor de ribbenkast nog meer omhoog komt, wat zorgt voor een grotere longexpansie.
	</li>
	<li>Uitzetting van de borstholte: Als het middenrif samentrekt en de intercostale spieren aangrijpen, zet de borstholte in meerdere richtingen uit. Deze uitzetting verlaagt de druk in de longen, waardoor er een drukverschil ontstaat tussen de buitenlucht en de lucht in het ademhalingssysteem. Als gevolg hiervan stroomt er lucht de longen in, waardoor de alveoli (kleine luchtzakjes) worden gevuld voor gasuitwisseling.</li>
</ol>

Geforceerde inademing: Tijdens periodes van verhoogde fysieke inspanning of wanneer er behoefte is aan verhoogde zuurstofinname, vindt geforceerde inademing plaats. De mechanica van geforceerde inademing omvat extra spieren om de longexpansie te maximaliseren:

<ol>
	<li>Sternocleidomastoïde spier: De sternocleidomastoïde spier in de nek speelt een belangrijke rol bij geforceerde inademing. Wanneer geactiveerd, tilt hij het sternum op, wat helpt bij verdere expansie van de borstholte.</li>
	<li>Scalene spieren: De scalene spieren bevinden zich aan beide kanten van de nek en tillen de bovenste ribben op tijdens geforceerde inademing. Hun samentrekking helpt meer ruimte te creëren voor longexpansie.</li>
	<li>Kleine borstspier: De kleine borstspier, gelegen onder de grote borstspier, zorgt ervoor dat de ribben omhoog komen en de borstholte groter wordt.</li>
</ol>

De rol van druk bij longventilatie

Voor een goede longventilatie is de wisselwerking tussen drie verschillende drukniveaus nodig:

<ol>
	<li>Intrapulmonale druk: Ook bekend als alveolaire druk, het verwijst naar de druk in de longen. Tijdens inademing (inademing) neemt de intrapulmonale druk af, waardoor er lucht in de longen stroomt. Daarentegen neemt de intrapulmonale druk toe tijdens uitademing, waardoor luchtuitdrijving wordt vergemakkelijkt.</li>
	<li>Intrapleurale druk: Deze druk bestaat in de pleuraholte, de ruimte tussen de pariëtale en viscerale pleurae. Deze is meestal lager dan de atmosferische en intrapulmonale druk vanwege de balans van krachten tussen longterugslag en borstwandexpansie, waardoor de longen tegen de borstwand aan blijven staan. Elke verandering in intrapleurale druk kan leiden tot longcollaps of andere ademhalingsproblemen.</li>
	<li>Atmosferische druk: Atmosferische druk is de druk die de atmosfeer van de aarde op een bepaalde locatie uitoefent. Het dient als basislijn waartegen de intrapulmonale druk wordt gemeten. Tijdens inademing (inademing) vergemakkelijkt de afname van de intrapulmonale druk onder de atmosferische druk de luchtinlaat, terwijl tijdens uitademing de toename van de intrapulmonale druk boven de atmosferische druk lucht uit de longen drijft.</li>
</ol>

Longventilatie: Inademing

Pulmonary ventilation is a vital process that ensures the exchange of oxygen and carbon dioxide in the lungs. It refers to the movement of air into and ...

Education

JoVE Core

Anatomy and Physiology

Anatomie en fysiologie

Unit 1

The Respiratory System

Het ademhalingsstelsel

KEY TERMS AND CONCEPTS

BELANGRIJKE TERMEN EN CONCEPTEN

pulmonary ventilation and breathing pressures

Pulmonary ventilation depends on breathing movements and the pressure changes that move air into and out of the lungs. It supports the exchange of oxygen and carbon dioxide by letting the body take in oxygen and remove waste carbon dioxide. Boyle's law is important here because changes in volume and pressure affect how air moves in the respiratory system.

Several respiratory volumes help describe how much air the lungs move. Tidal volume is the air inspired or expired during normal, quiet breathing. Inspiratory reserve volume is the extra air that can be forcefully inhaled after a normal breath, while expiratory reserve volume is the extra air that can be forcefully exhaled after a normal breath. Residual volume is the air that remains in the lungs after maximal expiration. These values are used to calculate vital capacity, which is the sum of tidal volume, inspiratory reserve volume, and expiratory reserve volume.

Normal inhalation begins when the diaphragm contracts and the external intercostal muscles contract. The diaphragm is a dome-shaped muscle that separates the thoracic cavity from the abdominal cavity, and when it flattens, the chest cavity gets larger. The external intercostal muscles lift and expand the rib cage, which also increases thoracic volume. As the chest cavity expands, intrapulmonary pressure falls and air flows from the atmosphere into the lungs.

Forced inhalation uses additional muscles when the body needs more oxygen, such as during physical exertion. The sternocleidomastoid muscle in the neck raises the sternum. The scalene muscles on either side of the neck lift the upper ribs. The pectoralis minor also helps raise the ribs and expand the chest cavity even more.

Breathing also depends on three related pressures. Intrapulmonary pressure, also called alveolar pressure, is the pressure inside the lungs. It drops during inspiration and rises during expiration. Intrapleural pressure is the pressure in the pleural cavity, between the parietal and visceral pleurae. It is usually lower than atmospheric and intrapulmonary pressure because of the balance between lung recoil and chest wall expansion, which helps keep the lungs expanded against the chest wall. If intrapleural pressure changes too much, lung collapse or other breathing problems can result. Atmospheric pressure is the pressure of the air around us, and it serves as the reference point for the pressure changes that move air in and out of the lungs.

Pulmonary Ventilation and Breathing Pressures

pulmonary-ventilation-and-breathing-pressures

overview of respiratory system

How Breathing Moves Air and Gases

The respiratory system moves air in and out of the body and exchanges oxygen and carbon dioxide with the environment. This gas exchange is part of respiration, which is essential for life. The system supplies the blood with oxygen so it can carry that oxygen to the rest of the body. Breathing starts when air enters through the nose or mouth. The nose and nasal cavity form the main external opening and the first part of the airway. Air then passes through the pharynx, or throat, which is shared...

nose and nasal cavity

How the Nose Filters and Senses Air

The nose filters, warms, moistens, and senses the air that enters the body. It also helps shape speech as sound vibrations pass through its large air spaces. The nose has an external part that is visible on the face and an internal part called the nasal cavity. The external nose is built from bone and hyaline cartilage, which gives it flexibility. It is covered by skin and muscle and lined with a mucous membrane. The frontal bone, nasal bones, and maxillary bone support this structure. The...

pharynx

Pharynx Pathways for Air and Food

The pharynx is a muscular tube lined with mucous membrane that connects the nasal cavities to the throat. It is divided into three parts: the nasopharynx, oropharynx, and laryngopharynx. Each part has a different role in moving air and food through the upper throat. The nasopharynx sits behind the nasal cavity and serves only as an air passage. Its upper region contains the pharyngeal tonsils, also called adenoids. These are clusters of lymphoid reticular tissue, similar to a lymph node, and...

larynx

Voice Box Anatomy and Function

The larynx is the voice box in the neck. It carries air into the lungs and helps produce voice. Its structure is complex because it must support both breathing and sound production. The larynx contains cartilage, muscles, and the vocal cords, also called vocal folds. It includes three large unpaired cartilages: the thyroid, cricoid, and epiglottis. It also includes three paired cartilages: the arytenoids, corniculates, and cuneiforms. Ligaments and membranes hold these parts together. The...

trachea

Trachea: Layers, Rings, and Airflow

The trachea is the windpipe, and it is a key airway in the human respiratory system. It carries air between the larynx and the bronchi so oxygen can reach the lungs. About half of the trachea lies in the neck, and it sits in front of the esophagus. In an average adult, the trachea is about 10 to 12 cm long. It extends from the larynx at the level of the sixth cervical vertebra to the level of the fifth thoracic vertebra. Its wall is supported by C-shaped cartilaginous rings. The back side is...

the bronchial tree

Bronchial Branching and Airflow Control

The bronchial tree carries air from the trachea into the lungs and helps control breathing. The trachea, or windpipe, connects the larynx to the bronchi. At the carina, the trachea splits into two primary bronchi. The right primary bronchus is wider, shorter, and more vertical than the left. Because of that shape, foreign objects and infections are more likely to enter the right lung. The carina is a cartilaginous ridge at the split in the airway. It helps keep the airway open. It also has...

alveoli and alveolar ducts

How Alveoli Enable Gas Exchange

The respiratory zone of the human body is where gas exchange happens. It begins when the terminal bronchioles branch into respiratory bronchioles, the smallest bronchiole type. These then lead into alveolar ducts and finally into clusters of alveoli. Alveoli are tiny air sacs that look like bunches of grapes. They connect to alveolar ducts, and a group of alveoli forms an alveolar sac. A single alveolus is about 200 μm wide, and its elastic shape lets it expand during inhalation. Nearby...

gross anatomy of the lungs

Lung Lobes, Airways, and Blood Flow

The lungs are paired organs that connect to the trachea through the left and right bronchi. Their base rests against the diaphragm, the dome-shaped muscle below the lungs. The lungs are covered by the pleurae and sit next to the mediastinum, the central space in the chest. The right lung is shorter and wider than the left lung, and it has a larger volume. The left lung has a cardiac notch, which is an indentation for the heart. The top of each lung is the apex, and the lower part is the base.

pleura of the lungs

Pleura Layers and Lung Protection

The pleura are membranes that protect the lungs inside the chest cavity. They are a type of serous membrane and wrap around each lung. The pleura have two layers: the visceral pleura and the parietal pleura. The visceral pleura covers the surface of the lung. The parietal pleura is the outer layer. It lines the thoracic wall, the mediastinum, and the diaphragm. The hilum is the point where the visceral and parietal layers connect. The space between these layers is called the pleural cavity. <br...

pressure relationships in thoracic cavity

pressure-relationships-in-thoracic-cavity

How Pressure Drives Breathing in the Lungs

Breathing depends on pressure changes in the lungs, chest, and airways. Pulmonary ventilation is the movement of air into and out of the lungs. It is driven by atmospheric pressure, intra-alveolar pressure inside the alveoli, and intrapleural pressure in the pleural cavity. Inhalation and exhalation rely on pressure differences between the atmosphere and the lungs. Gas pressure comes from the movement of confined molecules. Boyle’s law explains that pressure and volume are inversely...

pulmonary ventilation: inhalation

Pulmonary ventilation depends on breathing movements and the pressure changes that move air into and out of the lungs. It supports the exchange of oxygen and carbon dioxide by letting the body take in oxygen and remove waste carbon dioxide. Boyle's law is important here because changes in volume and pressure affect how air moves in the respiratory system. Several respiratory volumes help describe how much air the lungs move. Tidal volume is the air inspired or expired during normal, quiet...

pulmonary cycle: exhalation

Exhalation and Lung Pressure Changes

Exhalation is the process of expelling air from the lungs. It depends on pressure differences between the lungs and the atmosphere. During normal quiet breathing, exhalation is passive and does not require muscle contraction. The elastic recoil of the lungs and chest wall helps both structures return to their resting positions after inhalation. When the muscles used for inhalation stop working, the diaphragm and external intercostal muscles relax. The diaphragm moves upward, and the ribs move...

factors affecting pulmonary ventilation

What Changes Breathing Ease in the Lungs

Breathing ease in the lungs depends on alveolar surface tension, lung compliance, and airway resistance. These factors affect how hard it is to move air during pulmonary ventilation, along with the pressure difference between the outside environment and the lungs. Alveolar surface tension comes from the fluid lining the inside of the alveoli. Water molecules in this fluid attract each other more strongly than they attract the air, so the liquid tends to pull the alveoli inward. That force must...

respiratory volumes and capacities

Lung Volume Measurements in Breathing

Lung volume measurements show how air moves in and out of the respiratory system during breathing. They help explain how the body takes in oxygen and removes carbon dioxide. Respiratory volumes and capacities also give useful information about lung function. Tidal volume is the air breathed in and out during normal, quiet breathing. Inspiratory reserve volume is the extra air that can be forcefully inhaled beyond tidal volume. Expiratory reserve volume is the extra air that can be forcefully...

physical principles governing gas exchange

physical-principles-governing-gas-exchange

Gas Laws in Lung Gas Exchange

Gas laws explain how oxygen and carbon dioxide move during respiration. External respiration is the exchange of gases in the lungs. Oxygen diffuses into the blood, and carbon dioxide diffuses out. Internal respiration happens in body tissues, where the gases move in the opposite directions. Two gas laws guide this process: Dalton's law of partial pressures and Henry's law. Dalton's law says the total pressure of a gas mixture equals the sum of the pressures of each gas acting alone. The...

external and internal respiration

Gas Exchange in Lungs and Tissues

Gas exchange in the lungs and body tissues moves oxygen into the blood and removes carbon dioxide. External respiration happens in the lungs, where inhaled oxygen enters the alveoli, the tiny air sacs that provide a large surface area for diffusion. Oxygen moves across the thin alveolar membrane into the pulmonary capillaries because its partial pressure is higher in the alveoli than in the blood. At the same time, carbon dioxide moves in the opposite direction and is later breathed out during...

oxygen transport in the blood

How Hemoglobin Loads and Releases Oxygen

Hemoglobin is the main molecule that carries oxygen in blood. It is found in red blood cells and has four polypeptide chains, each attached to an iron-containing heme group. This structure lets one hemoglobin molecule bind up to four oxygen molecules quickly and reversibly. When hemoglobin is fully loaded with oxygen, it is called oxyhemoglobin. When it has released oxygen, it is called reduced hemoglobin, or deoxyhemoglobin. As hemoglobin binds oxygen, its shape changes, which helps it pick...

carbon dioxide transport in the blood

How Blood Carries Carbon Dioxide

Carbon dioxide is carried in the blood from body tissues to the lungs. Cells make about 200 mL of CO2 each minute, and the lungs remove about the same amount. The blood moves this waste gas in three main forms. A small amount, about 7-10%, stays dissolved in the plasma. Just over 20% binds to hemoglobin and forms carbaminohemoglobin. In this case, CO2 attaches to the amino acids of globin, not to the heme part of hemoglobin. The rest, about 70%, is carried as bicarbonate ions, or HCO3-. CO2...

hypoxia

Hypoxia: Types and Carbon Monoxide Poisoning

Hypoxia is a medical condition in which body tissues do not get enough oxygen. It can cause a bluish color in the skin and mucosae, especially in fair-skinned people. This sign is often seen when hemoglobin (Hb) saturation drops below 75%. Hypoxia can happen for several different reasons. Anemic hypoxia occurs when there are too few red blood cells (RBCs) or when RBCs have abnormal or too little Hb. Ischemic hypoxia comes from poor blood circulation or blocked blood flow, so blood becomes...

neural control of respiration

Brainstem Centers That Control Breathing

Breathing is controlled by nerve centers in the brainstem. These respiratory centers send nerve signals to the muscles that move the lungs. The main centers are in the medulla oblongata and the pons.

chemical factors affecting respiration centers

chemical-factors-affecting-respiration-centers

How Blood Gases Control Breathing Rate

Blood gases and blood pH help control breathing rate and depth. Changes in carbon dioxide, oxygen, and hydrogen ion levels in arterial blood are detected by chemoreceptors, which are special sensors in the body. Central chemoreceptors are found throughout the brain stem, including the ventrolateral medulla. Peripheral chemoreceptors are located in the aortic arch and carotid arteries. Together, these sensors help the respiratory system respond to chemical changes in the blood. Carbon dioxide...

other factors affecting respiration centers

other-factors-affecting-respiration-centers

Respiratory Reflexes That Change Breathing

Breathing is controlled by the brainstem, but it can also be changed by the nervous system and by body signals. The cerebral motor cortex can override the medullary respiratory centers and send signals directly to the breathing muscles. This makes voluntary actions like holding your breath or taking deeper breaths possible. That control is limited. When carbon dioxide, or CO2, builds up in the blood to a critical level, the brainstem respiratory centers start breathing again. This is why a...

hyperpnea and hyperventilation

Breathing Changes in Exercise and Anxiety

Breathing changes in exercise and anxiety can look similar, but they do not have the same cause. Hyperventilation is a higher-than-normal rate and depth of breathing. It often happens during anxiety attacks and can push out more carbon dioxide than the body needs to remove. When too much carbon dioxide is lost, the blood develops hypocapnia, which means an unusually low level of carbon dioxide. Hypocapnia can narrow cerebral blood vessels and reduce blood flow to the brain. This may cause...

chronic obstructive pulmonary disease

COPD Signs, Causes, and Lung Damage

COPD is a lung condition that causes ongoing breathing problems. It leads to shortness of breath, cough, and sputum production because the airways become blocked and airflow is reduced. Smoking is the main risk factor for COPD, and more than 80% of patients have a history of it. People with COPD often develop worsening dyspnea, or labored breathing. They may also cough often and get repeated lung infections. Many patients with COPD can develop respiratory failure. This happens when...

other pulmonary disorders

Asthma, TB, Lung Cancer, and Sleep Apnea

Asthma, lung cancer, tuberculosis, and sleep apnea are major pulmonary disorders. They affect breathing in different ways. Some are chronic, some are infectious, and some can become life-threatening if not found and treated early. Asthma is marked by chronic airway inflammation and hypersensitivity. It can cause airway obstruction from bronchial spasms, mucosal edema, increased mucus secretion, or epithelial damage. Triggers vary and can include allergens or emotional upset. Treatment often...

key terms and concepts

Explore pulmonary ventilation, lung volumes, and the pressure changes that drive inhalation, including the diaphragm, intercostal muscles, and key breathing pressures.

Pulmonary Ventilation and Breathing Pressures | JoVE K12

anatomy and physiology

JoVE Core Anatomy and Physiology showcases the anatomical and physiological details of the human body in comprehensive, clear, and engaging video animations. This collection of lessons focuses on the structures, components, functions, and requirements of the human body. It is complemented by scientist-in-action videos that demonstrate the application of this knowledge in real-world medical and research settings.

Alabama Course of Study Science

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From Molecules to Organisms: Structures and Processes

9-12.HA.1.9.b

Florida Department of Education

High School

Life Science

SC.912.L.14

SC.912.L.14.44

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The human digestive system consists of two major parts: the gastrointestinal &#8212; GI &#8212; tract and the accessory organs.
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Peritoneum

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histology-of-the-gastrointestinal-gi-tract

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In contrast, the arrival ...

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The pancreas is a pinkish-gray organ located behind the stomach. It extends from the duodenum to the spleen.
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In the gastric glands, the parietal cells are involved in hydrochloric acid or HCl formation.
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The incompetence of the lower esophageal sphincter results in the ...

Digestive System

Content elaboration: The digestive system consists of the gastrointestinal tract (alimentary canal) as well as various accessory organs including the teeth, tongue, salivary glands, liver, gallbladder and pancreas. The digestive system processes and supplies the molecules needed to sustain the living tissues within the body through the absorption of nutrients. Six major functions of the digestive system include secretion, ingestion, mechanical processing, enzymatic digestion, absorption and excretion. The lining of the digestive system protects surrounding tissues from the mechanical and enzymatic stresses of the digestive process. Processes of the digestive system include the mechanical and chemical breakdown of food into small molecules which are then absorbed by the digestive tract. Specific actions within the digestive system include mastication, peristalsis, segmentation and the release of hormones and enzymes necessary for digestion. The metabolic functions of the accessory organs play strategic roles in the breakdown of food products, the maintenance of glucose levels within the blood and the regulation of homeostasis in the body. Indigestible material is excreted as waste. Homeostatic imbalances are explored. These include, but are not limited to, conditions such as gallstones, heartburn, ulcers, dehydration, diarrhea, cirrhosis and cancers of the digestive system. Investigations are used to understand and explain the digestive system in a variety of inquiry and design scenarios that can incorporate evolutionary concepts, scientific reasoning, comparative analysis, communication skills and real-world applications.

Digestive System

Pulmonary Ventilation and Breathing Pressures

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