Respiratory physiology

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Respiratory physiology is the branch of human physiology focusing upon respiration.

Topics include:

Contents 1 Volumes 2 Mechanics 3 Circulation, ventilation, and perfusion 4 Gas exchange/transport (primarily oxygen and carbon dioxide) 5 Control and response 6 Disorders 7 See also 8 Additional images 9 References 10 External links

[edit] Volumes

• lung volumes
• vital capacity
• functional residual capacity
• dead space
• spirometry
• body plethysmography
• peak flow meter

[edit] Mechanics

Breathing in, or inhaling, is usually an active movement. The contraction of the diaphragm muscles cause a pressure variation, which is equal to the pressures caused by elastic, resistive and inertial components of the respiratory system.

Where P_el equals the product of elastance E (inverse of compliance) and volume of the system V, P_re equals the product of flow resistance R and time derivate of volume V (which is equivalent to the flow), P_in equals the product of inertance I and second time derivate of V. R and I are sometimes referred to as Rohrer's constants.

• Anatomy: pleural cavity, thoracic diaphragm, Intercostales externi muscles, Intercostales interni muscles
• inhalation and exhalation
• lung, pulmonary alveolus
• With insufficient pulmonary surfactant, the pulmonary alveoli collapse, causing atelectasis (in infants, infant respiratory distress syndrome)
• the law of Laplace,
• compliance (physiology) - decreased with fibrosis, increased with emphysema^[1]
• Poiseuille's law
• asthma and COPD
• hysteresivity

[edit] Circulation, ventilation, and perfusion

• pulmonary circulation
• positive pressure ventilation
• hypoxic vasoconstriction
• ventilation (physiology), perfusion, ventilation/perfusion ratio (V/Q), and ventilation/perfusion scan
• shunts: right-to-left (tetralogy of fallot), left-to-right (patent ductus arteriosus)
• respiratory rate and respirometer

[edit] Gas exchange/transport (primarily oxygen and carbon dioxide)

• gas exchange
• Dalton's law
• hemoglobin
• oxygen-hemoglobin dissociation curve, Bohr effect, Haldane effect
• carbonic anhydrase
• oxyhemoglobin
• respiratory quotient
• arterial blood gas

[edit] Control and response

• control of respiration
• reticular formation
• pons (apneuistic and pneumotaxic)
• chemoreceptors (medulla, carotid body, aortic body)
• Hering-Breuer reflex
• involuntary control of respiration
• exercise
• hyperoxia
• hypoxemia (hypoxic hypoxia)

[edit] Disorders

• altitude sickness
• asthma
• carbon monoxide poisoning
• chronic obstructive pulmonary disease
• emphysema
• infant respiratory distress syndrome
• pulmonary edema

[edit] See also

• breath sounds
• pulmonology
• respiratory system
• Wikipedia:MeSH G09#MeSH G09.772 --- respiratory physiology

[edit] Additional images

[edit] References

1. ^ Compliance

[edit] External links

• Overview at Johns Hopkins University
• Overview at Medical College of Georgia

v • d • e Respiratory system, physiology: respiratory physiology Volumes lung volumes - vital capacity - functional residual capacity - respiratory minute volume - closing capacity - dead space - spirometry - body plethysmography - peak flow meter - thoracic independent volume - bronchial challenge test Airways ventilation (V) (positive pressure) - breath (inhalation, exhalation) -respiratory rate - respirometer - pulmonary surfactant - compliance - hysteresivity - airway resistance Blood pulmonary circulation - perfusion (Q) - hypoxic pulmonary vasoconstriction - pulmonary shunt Interactions ventilation/perfusion ratio (V/Q) and scan - zones of the lung - gas exchange - pulmonary gas pressures - alveolar gas equation - hemoglobin - oxygen-haemoglobin dissociation curve (2,3-DPG, Bohr effect, Haldane effect) - carbonic anhydrase (chloride shift) - oxyhemoglobin - respiratory quotient - arterial blood gas - diffusion capacity - Dlco Control of respiration pons (pneumotaxic center, apneustic center) - medulla (dorsal respiratory group, ventral respiratory group) - chemoreceptors (central, peripheral) - pulmonary stretch receptors (Hering-Breuer reflex) Insufficiency high altitude - oxygen toxicity - hypoxia