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

Chronic Obstructive Pulmonary Disease01:24

Chronic Obstructive Pulmonary Disease

3.1K
COPD is defined as a heterogeneous lung condition marked by persistent respiratory symptoms such as dyspnea, cough, and sputum production, caused by abnormalities in the airways that cause airflow obstruction.
Smoking is a primary risk factor for COPD, with over 80% of patients having a history of it. Patients typically experience progressive dyspnea or labored breathing, frequent coughing, and recurrent pulmonary infections. Many eventually succumb to respiratory failure, characterized by...
3.1K
Acute Respiratory Failure-II01:21

Acute Respiratory Failure-II

1.5K
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:
1.5K
Acute Respiratory Failure-III01:30

Acute Respiratory Failure-III

1.1K
Hypercapnic respiratory failure, also known as Type 2 or ventilatory respiratory failure, is a severe condition characterized by the body's inability to effectively remove carbon dioxide (CO2) from the bloodstream. It leads to an arterial CO2 pressure (PaCO2) exceeding 45 mmHg and a blood pH above 7.35. This situation indicates that the body's ventilatory demand, or the ventilation needed to maintain normal PaCO2 levels, surpasses its supply or the maximum gas flow achievable without...
1.1K
Factors Affecting Pulmonary Ventilation01:19

Factors Affecting Pulmonary Ventilation

3.6K
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...
3.6K
Hyperpnea and Hyperventilation01:25

Hyperpnea and Hyperventilation

3.7K
Hyperventilation refers to a higher-than-normal rate and depth of breathing, often associated with anxiety attacks. This excessive breathing surpasses the body's need to expel CO2, leading to a condition known as hypocapnia - an unusually low level of carbon dioxide in the blood. Hypocapnia can constrict cerebral blood vessels, reducing blood flow to the brain, which may result in dizziness or fainting. Early signs include tingling and muscle spasms in the hands and face, caused by falling...
3.7K
Chronic Obstructive Pulmonary Disease-I: Introduction01:20

Chronic Obstructive Pulmonary Disease-I: Introduction

4.1K
Chronic Obstructive Pulmonary Disease (COPD) is a long-lasting respiratory condition requiring continuous attention and care. It is a progressive lung disease that leads to breathing challenges due to airflow obstruction. It manifests as persistent respiratory symptoms and restricted airflow resulting from abnormalities in the airways and alveoli, usually due to long-term exposure to harmful particles or gases. COPD mainly consists of two primary conditions: emphysema and chronic bronchitis.
4.1K

You might also read

Related Articles

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

Sort by
Same author

Occupational hazard awareness and safety-related knowledge among EMS students: evidence of a potential gap.

Scientific reports·2026
Same author

Corrigendum to "LLM predicts human behavior: A BERT-based approach for conscientiousness personality trait detection from online content" [Acta Psychologica 266 (2026), 106832].

Acta psychologica·2026
Same author

Evaluation of Video-Based Instruction and a 360° Virtual Reality Module on Personal Protective Equipment Competency and Infection Prevention in Healthcare Settings: A Quasi-Experimental Study.

Healthcare (Basel, Switzerland)·2026
Same author

Immune and non-immune hydrops fetalis in a Saudi tertiary center: etiologies, antenatal predictors, perinatal outcomes, and one-year survival in a seven-year cohort.

Frontiers in pediatrics·2026
Same author

LLM predicts human behavior: A BERT-based approach for conscientiousness personality trait detection from online content.

Acta psychologica·2026
Same author

Low muscle mass in interstitial lung disease: a systematic review and meta-analysis of prevalence and clinical associations.

BMC pulmonary medicine·2026

Related Experiment Video

Updated: Mar 22, 2026

Author Spotlight: Integrating Alveolar-Capillary Reserve Measurements in Exercise Adaptation and Therapeutic Strategies
08:44

Author Spotlight: Integrating Alveolar-Capillary Reserve Measurements in Exercise Adaptation and Therapeutic Strategies

Published on: February 2, 2024

1.5K

Exercise Ventilatory Inefficiency Adds to Lung Function in Predicting Mortality in COPD.

J Alberto Neder1,2, Abdullah Alharbi1, Danilo C Berton3

  • 1a Respiratory Investigation Unit & Laboratory of Clinical Exercise Physiology , Queen's University & Kingston General Hospital , Kingston , ON , Canada.

COPD
|April 15, 2016
PubMed
Summary
This summary is machine-generated.

Excess exercise ventilation, measured by the ventilation to carbon dioxide output ratio, independently predicts mortality in chronic obstructive pulmonary disease (COPD). This finding adds crucial prognostic information beyond resting lung function for COPD patients.

Keywords:
Survival; COPD; ventilation; cardiopulmonary exercise test; physiology

More Related Videos

Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise
07:09

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

Published on: February 20, 2017

13.8K
Inspiratory Muscle Training as an Adjunct to the Treatment of Weaning Failure in Critically Ill Patients: A Practical Guide
04:16

Inspiratory Muscle Training as an Adjunct to the Treatment of Weaning Failure in Critically Ill Patients: A Practical Guide

Published on: January 30, 2026

795

Related Experiment Videos

Last Updated: Mar 22, 2026

Author Spotlight: Integrating Alveolar-Capillary Reserve Measurements in Exercise Adaptation and Therapeutic Strategies
08:44

Author Spotlight: Integrating Alveolar-Capillary Reserve Measurements in Exercise Adaptation and Therapeutic Strategies

Published on: February 2, 2024

1.5K
Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise
07:09

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

Published on: February 20, 2017

13.8K
Inspiratory Muscle Training as an Adjunct to the Treatment of Weaning Failure in Critically Ill Patients: A Practical Guide
04:16

Inspiratory Muscle Training as an Adjunct to the Treatment of Weaning Failure in Critically Ill Patients: A Practical Guide

Published on: January 30, 2026

795

Area of Science:

  • Pulmonary Medicine
  • Cardiopulmonary Exercise Testing
  • Prognostic Biomarkers

Background:

  • Resting lung function in chronic obstructive pulmonary disease (COPD) only partially predicts mortality risk.
  • Increased ventilation during exercise in COPD is linked to disease progression and poor prognosis.

Purpose of the Study:

  • To determine if excess exercise ventilation adds to resting lung function in predicting mortality in COPD patients.
  • To investigate the prognostic value of the ventilation to carbon dioxide output (VCO2) ratio during exercise.

Main Methods:

  • 288 COPD patients underwent incremental cardiopulmonary exercise testing.
  • Excess exercise ventilation was defined as an increase in the lowest (nadir) ventilation to VCO2 ratio.
  • Patients were followed for mortality, with logistic regression and Kaplan-Meier analyses performed.

Main Results:

  • The ventilation/VCO2 nadir was the sole exercise variable that predicted all-cause and respiratory mortality when added to clinical factors.
  • A ventilation/VCO2 nadir > 34, especially with low inspiratory capacity/total lung capacity (IC/TLC) ratio, significantly reduced survival.
  • Excess exercise ventilation proved to be an independent prognostic marker across all COPD severities.

Conclusions:

  • Exercise ventilation abnormalities provide prognostic information beyond traditional measures in COPD.
  • Physiological factors beyond airway dysfunction and lung mechanics are critical for disease course prediction in COPD.