Dead space

You don't need to be Editor-In-Chief to add or edit content to WikiDoc. You can begin to add to or edit text on this WikiDoc page by clicking on the edit button at the top of this page. Next enter or edit the information that you would like to appear here. Once you are done editing, scroll down and click the Save page button at the bottom of the page.

WikiDoc Resources for Dead space
Articles
Most recent articles on Dead space Most cited articles on Dead space Review articles on Dead space Articles on Dead space in N Eng J Med, Lancet, BMJ
Media
Powerpoint slides on Dead space Images of Dead space Photos of Dead space Podcasts & MP3s on Dead space Videos on Dead space
Evidence Based Medicine
Cochrane Collaboration on Dead space Bandolier on Dead space TRIP on Dead space
Clinical Trials
Ongoing Trials on Dead space at Clinical Trials.gov Trial results on Dead space Clinical Trials on Dead space at Google
Guidelines / Policies / Govt
US National Guidelines Clearinghouse on Dead space NICE Guidance on Dead space NHS PRODIGY Guidance FDA on Dead space CDC on Dead space
Books
Books on Dead space
News
Dead space in the news Be alerted to news on Dead space News trends on Dead space
Commentary
Blogs on Dead space
Definitions
Definitions of Dead space
Patient Resources / Community
Patient resources on Dead space Discussion groups on Dead space Patient Handouts on Dead space Directions to Hospitals Treating Dead space Risk calculators and risk factors for Dead space
Healthcare Provider Resources
Symptoms of Dead space Causes & Risk Factors for Dead space Diagnostic studies for Dead space Treatment of Dead space
Continuing Medical Education (CME)
CME Programs on Dead space
International
Dead space en Espanol Dead space en Francais
Businness
Dead space in the Marketplace Patents on Dead space
Experimental / Informatics
List of terms related to Dead space

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Phone:617-525-6884

Please Take Over This Page and Apply to be Editor-In-Chief for this topic: There can be one or more than one Editor-In-Chief. You may also apply to be an Associate Editor-In-Chief of one of the subtopics below. Please mail us [2] to indicate your interest in serving either as an Editor-In-Chief of the entire topic or as an Associate Editor-In-Chief for a subtopic. Please be sure to attach your CV and or biographical sketch.

In physiology, dead space is air that is inhaled by the body in breathing, but does not partake in gas exchange.

In adults, it is usually in the range of 150 mL.^[1]

Understanding dead space

Not all the air we breathe in is able to be used for the exchange of oxygen and carbon dioxide. About a third of every resting breath is exhaled exactly as it came into the body.

Because of dead space, taking deep breaths more slowly (e.g. ten 500 mL breaths per minute) is more effective than taking shallow breaths quickly (e.g. twenty 250 mL breaths per minute). Although the amount of gas per minute is the same (5 L/min), a large proportion of the shallow breaths is dead space, and does not allow oxygen to get into the blood.

Dead space can be enlarged (and better envisaged) by breathing into a long tube. Even though one end of the tube is open to the air, when one inhales, it is mostly the carbon dioxide from expiration. Using a snorkel increases a diver's dead space in the airways.

Components

Dead space can be divided into two components: "anatomic" and "physiologic".^[1]

Anatomical dead space

Anatomical dead space is the gas in the conducting areas of the respiratory system, such as the mouth and trachea, where the air doesn't come to the alveoli of the lungs.

It is normally equal in milliliters to your body weight in pounds. A 150 lb (68 kg) male would have an anatomical dead space of about 150 mL. 1 mL per lb or 2.2 mL per kilogram of body weight. This is the same conversion of kilograms to pounds, except the final unit is in mL. This is about a third of the resting tidal volume (450-500 mL).

Anatomic dead space is the volume of the conducting airways. It may be measured by Fowler's Method, a nitrogen washout technique.^[1][1][1] It increases with an increase in tidal volume and is dependent on posture.

Physiological dead space

The physiological dead space is equal to the anatomical dead space plus the alveolar dead space.^[1]

Alveolar dead space is the area in the alveoli that does get air to be exchanged, but there is not enough blood flowing through the capillaries for exchange to be effective.^[1] It is normally very small (less than 5 mL) in healthy individuals. It can increase dramatically in some lung diseases.

Physiologic dead space can be measured by Bohr's method.^[1][1]

An equation and example are provided below:

• V_D = dead space
• V_T = tidal volume
• P_aCO2 = partial pressure of carbon dioxide in arteries
• P_ECO2 = partial pressure of carbon dioxide in exhaled air

See also

• Christian Bohr
• respiratory physiology

References

External links

• Overview at jhmi.edu
• Overview at ccmtutorials.com

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

v • d • e WikiDoc Research Resources for Dead space
Articles on Dead space	Most recent articles on Dead space • Most cited articles on Dead space • Review articles on Dead space • Articles on Dead space in N Eng J Med, Lancet, BMJ
Media (Slides, Video, Images, MP3) on Dead space	Powerpoint slides on Dead space • Images of Dead space • Photos of Dead space • Podcasts & MP3s on Dead space • Videos on Dead space
Evidence Based Medicine Regarding Dead space	Cochrane Collaboration on Dead space • Bandolier on Dead space • TRIP on Dead space
Cost Effectiveness of Dead space	Cost Effectiveness of Dead space
Clinical Trials Involving Dead space	Ongoing Trials on Dead space at Clinical Trials.gov • Trial results on Dead space • Clinical Trials on Dead space at Google
Guidelines / Policies / Government Resources (FDA/CDC) Regarding Dead space	US National Guidelines Clearinghouse on Dead space • NICE Guidance on Dead space • NHS PRODIGY Guidance • FDA on Dead space • CDC on Dead space
Textbook Information on Dead space	Books and Textbook Information on Dead space
Pharmacology Resources on Dead space	Dosing of Dead space • Drug interactions with Dead space • Side effects of Dead space • Allergic reactions to Dead space • Overdose information on Dead space • Carcinogenicity information on Dead space • Dead space in pregnancy • Pharmacokinetics of Dead space •
Genetics, Pharmacogenomics, and Proteinomics of Dead space	Genetics of Dead space • Pharmacogenomics of Dead space • Proteomics of Dead space
Newstories on Dead space	Dead space in the news • Be alerted to news on Dead space • News trends on Dead space
Commentary on Dead space	Blogs on Dead space
Patient Resources on Dead space	Patient resources on Dead space • Discussion groups on Dead space • Patient Handouts on Dead space • Directions to Hospitals Treating Dead space • Risk calculators and risk factors for Dead space
Healthcare Provider Resources on Dead space	Symptoms of Dead space • Causes & Risk Factors for Dead space • Diagnostic studies for Dead space • Treatment of Dead space
Continuing Medical Education (CME) Programs on Dead space	CME Programs on Dead space
International Resources on Dead space	Dead space en Espanol • Dead space en Francais
Business Resources on Dead space	Dead space in the Marketplace • Patents on Dead space
Informatics Resources on Dead space	List of terms related to Dead space

de:Totraum (Atmung)uk:Мертвий простір

WikiDoc Help Menu Quick Start.. Get Started Here! How to Login How to Search Pages How to Start a New Page How to Edit a Page Cheat Sheet Editing basics Learning Basic Formatting How to make Links in WikiDoc & to External Sites How to Make Lists How to Ignoring Formatting Adding References or Footnotes to Articles Tracking Changes You Have Made How to Put an Article Into a Category When Multiple Topics Should Go To The Same Page (MI, Acute MI, AMI) Using Redirection Advanced editing How to Make Tables How to Insert Images and Other Media How to Add Video Help:How to Make Columns Web Colors How To Make Templates How to Move Pages Inserting Dynamic Dates and Times Inserting WikiDoc Statistics Editing the Table of Contents Communicating your edits Let others know what you changed: The importance of Edit Summaries Minor Edits Edit Conflicts Help Videos You Can Watch Getting Started Video

Acknowledgement and Attribution Regarding Sources of Content

Some of the initial content on this page may be incorporated in part from copyleft sources in the public domain including wikis such as Wikipedia and AskDrWiki. Drug information for patients came from the The National Library of Medicine. Infectious disease information may have come from the Centers for Disease Control (CDC). Differential Diagnoses are drawn from clinicians as well as an amalgamation of 3 sources: 1.The Disease Database; 2. Kahan, Scott, Smith, Ellen G. In A Page: Signs and Symptoms. Malden, Massachusetts: Blackwell Publishing, 2004:3; 3. Sailer, Christian, Wasner, Susanne. Differential Diagnosis Pocket. Hermosa Beach, CA: Borm Bruckmeir Publishing LLC, 2002:7 .