Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Mechanical Ventilation I: Indication and Settings01:29

Mechanical Ventilation I: Indication and Settings

Mechanical ventilation is a life-saving technique for managing acute respiratory failure and other respiratory complications. The process involves using a machine known as a ventilator to supply oxygen to the lungs and assist in removing carbon dioxide. It serves as a bridge to long-term mechanical ventilation or a temporary measure until ventilatory support is discontinued. The ventilator can maintain this function for a prolonged period, providing critical support for patients until they can...
Mechanical Ventilation II: Invasive Ventilation01:23

Mechanical Ventilation II: Invasive Ventilation

Ventilators are essential medical equipment used to aid patients with respiratory difficulties. Their primary function is to assist or replace spontaneous breathing by providing mechanical ventilation. There are two general classes of mechanical ventilators: negative-pressure and positive-pressure ventilators.
Negative-Pressure Ventilators
Negative-pressure ventilators create a vacuum around the chest or body to draw air into the lungs, simulating breathing. This method does not require an...
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...
Ventilatory Modes01:14

Ventilatory Modes

Mechanical ventilators are life-saving devices that support or replace spontaneous breathing. They deliver breaths to patients through varying methods known as ventilator modes. Understanding these modes is critical for healthcare providers managing patients with respiratory failure.
There are three ventilatory modes: full support, partial support, and spontaneous. These are described below.
Full Support Modes
Full support modes include controlled mechanical ventilation, continuous mandatory...
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...
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...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Venous return versus cardiac function: who drives the circulation?

Intensive care medicine·2026
Same author

Venous waterfalls mainly buffer backward pressure transmission.

Intensive care medicine experimental·2026
Same author

Three decades of hemodynamic monitoring (1995-2025): from invasive pressure based hemodynamic profiling to functional physiology.

Current opinion in critical care·2026
Same author

A comprehensive cross-sectional study of bedside monitor alarm characteristics and alarm load across hospital units.

Scientific reports·2026
Same author

The Effective Management of Shock: Moving From Physiology to Guidelines to Personalized Medicine.

Critical care medicine·2026
Same author

Defining the Determinants of Tissue Perfusion at the Bedside in Septic Shock Patients.

Anesthesiology·2026
Same journal

Cardiogenic shock - toward phenotype-directed, precision management.

Current opinion in critical care·2026
Same journal

The future of critical care nutrition: from calorie counting to precision personalized metabolism therapy.

Current opinion in critical care·2026
Same journal

Editorial introduction.

Current opinion in critical care·2026
Same journal

Generative artificial intelligence for outcome prediction in critical care: the future is now?

Current opinion in critical care·2026
Same journal

Feeding under support in critical care illness: metabolic and nutritional management during extracorporeal membrane oxygenation and continuous renal replacement therapy.

Current opinion in critical care·2026
Same journal

Multinational collaborations in critical care research: feasible and useful?

Current opinion in critical care·2026
See all related articles

Related Experiment Video

Updated: May 23, 2026

Ex Vivo Porcine Experimental Model for Studying and Teaching Lung Mechanics
12:09

Ex Vivo Porcine Experimental Model for Studying and Teaching Lung Mechanics

Published on: April 19, 2024

Heart lung interactions during mechanical ventilation.

Michael R Pinsky1

  • 1Department of Critical Care Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania 15261, USA. pinskymr@upmc.edu

Current Opinion in Critical Care
|April 5, 2012
PubMed
Summary
This summary is machine-generated.

Pulse pressure variation (PPV) and stroke volume variation (SVV) indicate fluid responsiveness during mechanical ventilation. Understanding their physiological basis is key to accurate interpretation in critical care settings.

Related Experiment Videos

Last Updated: May 23, 2026

Ex Vivo Porcine Experimental Model for Studying and Teaching Lung Mechanics
12:09

Ex Vivo Porcine Experimental Model for Studying and Teaching Lung Mechanics

Published on: April 19, 2024

Area of Science:

  • Critical Care Medicine
  • Cardiovascular Physiology
  • Respiratory Mechanics

Background:

  • Mechanical ventilation significantly impacts cardiovascular hemodynamics.
  • Monitoring fluid responsiveness is crucial for optimizing patient management in intensive care.

Purpose of the Study:

  • To review recent literature on the hemodynamic effects of mechanical ventilation.
  • To elucidate the mechanisms and applications of dynamic indices of fluid responsiveness.

Main Methods:

  • Literature review of studies investigating hemodynamic effects of mechanical ventilation.
  • Analysis of physiological determinants of pulse pressure variation (PPV) and stroke volume variation (SVV).

Main Results:

  • PPV and SVV are dynamic indicators of volume responsiveness, driven by intrathoracic pressure changes.
  • Accuracy of PPV/SVV is influenced by tidal volume; they remain valuable in specific scenarios like one-lung ventilation.
  • Noninvasive methods and thoracic impedance can estimate PPV/SVV.
  • The PPV-to-SVV ratio aids in identifying vasopressor needs in hypotensive patients.

Conclusions:

  • PPV and SVV effectively predict volume responsiveness.
  • Understanding the physiological basis of these indices is essential for their appropriate clinical application.