NUR%20214%20Ventilation%20Fall%202010

NUR%20214%20Ventilation%20Fall%202010 - Ventilation and...

Info iconThis preview shows pages 1–11. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Ventilation and Perfusion: Concepts of Respiratory Function NUR 214 Functions of the Pulmonary System Ventilation of the Alveoli Diffusion of Gases into and out of the blood Perfusion of the lungs Promotes delivery of blood high in oxygen and low in carbon dioxide to the organs and tissues Structures of the Pulmonary System Two Lungs Right Lung ( 3 lobes – upper, middle and lower) Left Lung (2 lobes – upper and lower) Bronchi – responsible for air delivery Blood Vessels Chest Wall (Thoracic Cage) Mediastinum Heart, Great Vessels (aorta and vena cava) Esophagus Protection from Contamination Upper Respiratory Tract Mucosa Nasal Hairs and Turbinates Mucus Blanket Cilia Alveolar Macrophages Irritant Receptors in Nares Triggers Sneeze Irritant Receptors in Trachea and Large Airways Triggers Cough Gas Exchange Airways Alveoli Primary Gas-Exchange Units Birth - 25 million alveoli Adulthood 300 million alveoli Contain Epithelial Cells Type I cells provide structure Type II cells secret Surfactant Lipoprotein that coats inner surface of alveoli Prevents alveolar collapse Surfactant Lines alveolar side of the alveolarcapillary membrane Production is inadequate in premature infants especially below 28 weeks gestation L owers alveolar surface tension Normal alveoli are easier to inflate a low lung volumes (after expiration) than at high lung volumes (after inspiration) Requires adequate blood flow to replenish surfactant If surfactant production is not sufficient, alveolar surface tension increases alveolar collapse decreased lung expansion Increased work of breathing Severe O2 / CO2 gas-exchange abnormalities Respiratory distress syndrome in adults and children has a component of defective surfactant production Diffusion of gases Partial pressure gradient influences diffusion of each gas Gases move from higher to lower partial pressure PO2 - from alveoli to blood PCO2 - from blood to alveoli Greater the pressure gradient, the more rapid the diffusion Pressure gradient low at high altitudes Oxygen therapy increases alveolar PO2 Alveolar-capillary membrane ( Gas Exchange) Oxygen Cascade Declining oxygen tension from atmosphere to mitochondria Ventilation vs. Respiration Ventilation Mechanical Movement of gas or air into or out of the lungs...
View Full Document

This note was uploaded on 02/14/2011 for the course NUR 214 taught by Professor Criswell during the Spring '08 term at Purdue.

Page1 / 30

NUR%20214%20Ventilation%20Fall%202010 - Ventilation and...

This preview shows document pages 1 - 11. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online