Related Experiment Video

Updated: Aug 8, 2026

Phase-Resolved Functional Lung MRI for Pulmonary Ventilation and Perfusion (V/Q) Assessment
05:56

Phase-Resolved Functional Lung MRI for Pulmonary Ventilation and Perfusion (V/Q) Assessment

Published on: August 9, 2024

Regional pulmonary perfusion, inflation, and ventilation defects in bronchoconstricted patients with asthma

R Scott Harris1, Tilo Winkler, Nora Tgavalekos

  • 1Department of Medicine (Pulmonary and Critical Care Unit and General Medicine Unit), Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA. rharris@partners.org

American Journal of Respiratory and Critical Care Medicine
|May 13, 2006
PubMed
Abstract

More Related Videos

Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise07:09

Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise

Published on: February 20, 2017

Related Concept Videos

Atelectasis II: Pathophysiology01:10

Atelectasis II: Pathophysiology

Atelectasis develops when alveoli lose their air and collapse inward. Because lung tissue is naturally elastic, these air sacs shrink rather than remaining open. Collapsed alveoli are no longer ventilated, reducing their role in gas exchange. Blood flow may continue in these regions, creating a ventilation–perfusion mismatch. Clinical findings include decreased breath sounds, dullness to percussion, reduced chest expansion, and decreased tactile fremitus as sound transmission through collapsed...
Factors Affecting Pulmonary Ventilation01:19

Factors Affecting Pulmonary Ventilation

Besides the pressure difference between the external environment and the lungs, the airflow rate and ease of pulmonary ventilation are also influenced by three other factors: surface tension of the fluid in the alveoli, compliance of the lungs, and airway resistance.
Alveolar Surface Tension
The alveolar fluid lines the luminal surface of the alveoli and exerts a force called surface tension. This force is caused by the polar water molecules in the liquid being more strongly attracted to each...
Acute Respiratory Failure-II01:21

Acute Respiratory Failure-II

Type I Respiratory Failure, or hypoxemic respiratory failure, occurs when the partial pressure of oxygen (PaO2) in arterial blood falls below 60 mmHg while breathing room air without a corresponding increase in arterial carbon dioxide levels (PaCO2). This condition highlights a significant impairment in the lungs' capacity to oxygenate the blood.
The underlying physiological abnormalities that contribute to hypoxemic respiratory failure include:
Pulmonary Ventilation: Inhalation01:24

Pulmonary Ventilation: Inhalation

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 out of the lungs, enabling the body to obtain oxygen and remove waste carbon dioxide. In this article, we will explore the intricacies of pulmonary ventilation, including its underlying principles, mechanisms, and the interplay of pressures within the respiratory system.
Boyle's law becomes particularly pertinent when examining respiratory...
Pulmonary Cycle: Exhalation01:17

Pulmonary Cycle: Exhalation

In terms of human respiration, the act of expelling air, known as exhalation (or expiration), operates on the principle of pressure gradients. During expiration, the pressure within the lungs exceeds that of the surrounding atmosphere. Under normal conditions, quiet breathing involves passive exhalation and is free of muscular contractions. This is because the exhalation process is driven by the natural elastic recoil of the lungs and chest wall, both of which have an inherent tendency to...
Pressure Relationships in Thoracic Cavity01:24

Pressure Relationships in Thoracic Cavity

Breathing, otherwise known as pulmonary ventilation, is the process of air movement into and out of the lungs. The main mechanisms propelling pulmonary ventilation are atmospheric pressure (Patm), intra-pulmonary (Ppul ) or intra-alveolar pressure (Palv) within the alveoli, and intrapleural pressure (Pip) within the pleural cavity.
Breathing Mechanisms
Both intra-alveolar and intrapleural pressures rely on specific lung properties. The ability to breathe—allowing air to enter the lungs during...