Related Experiment Video
Updated: Aug 3, 2026
07:52
Expired CO2 Measurement in Intubated or Spontaneously Breathing Patients from the Emergency Department
Published on: January 30, 2011
Inspired oxygen and oxygen transfer during artificial ventilation for respiratory failure
British Journal of Anaesthesia
|January 1, 1983
Summary
Increasing inspired oxygen in artificially ventilated patients with severe respiratory failure improved oxygen transfer. Less severe cases showed no change, supporting the ventilation/perfusion mismatch hypothesis.
Area of Science:
- Pulmonary medicine
- Respiratory physiology
Background:
- Artificial ventilation is crucial for managing respiratory failure.
- Assessing arterial oxygenation and oxygen transfer impairment is vital for patient management.
Purpose of the Study:
- To investigate the effect of increased fraction of inspired oxygen (FIO2) on arterial oxygenation in mechanically ventilated patients.
- To evaluate whether elevated FIO2 impairs pulmonary oxygenating efficiency.
Main Methods:
- Measured arterial oxygenation at varying FIO2 levels in patients with respiratory failure.
- Assessed oxygen transfer impairment using the difference between pulmonary end-capillary and arterial oxygen content (Cc'O2-CaO2) as an indicator of venous admixture.
Main Results:
- In patients with severe gas exchange impairment (Cc'O2-CaO2 > 1 ml dl-1), increasing FIO2 initially reduced impairment.
- Patients with less severe impairment showed no significant change with increased FIO2.
Conclusions:
- The findings support the ventilation/perfusion mismatch hypothesis.
- Increased inspired oxygen did not demonstrate impairment of pulmonary oxygenating efficiency in this study.
More Related Videos
07:15Preoxygenation Techniques for Tracheal Intubation in Critically Ill Adults Utilizing Oxygen Mask and Noninvasive Ventilation
Published on: December 5, 2025
04:16Inspiratory Muscle Training as an Adjunct to the Treatment of Weaning Failure in Critically Ill Patients: A Practical Guide
Published on: January 30, 2026
Related Concept Videos
01:20Gas Exchange and Transport
Gas exchange, the intake of molecular oxygen (O2) from the environment and the outflow of carbon dioxide (CO2) into the environment, is necessary for cellular function. Gas exchange during respiration occurs largely via the movement of gas molecules along pressure gradients. Gas travels from areas of higher partial pressure to areas of lower partial pressure. In mammals, gas exchange occurs in the alveoli of the lungs, which are adjacent to capillaries and share a membrane with them.
01:23Physiological Control of Respiration
Introduction
Breathing, a seemingly passive process, is regulated by the respiratory center in the brainstem. This center coordinates the involuntary control of respirations, which means it occurs without conscious effort, ensuring a smooth and uninterrupted pattern.
Regulation of Ventilation
The body maintains ventilation by monitoring levels of carbon dioxide (CO2), oxygen (O2), and hydrogen ion concentration (pH) in the arterial blood. Among these factors, the level of CO2 plays a crucial...
Breathing, a seemingly passive process, is regulated by the respiratory center in the brainstem. This center coordinates the involuntary control of respirations, which means it occurs without conscious effort, ensuring a smooth and uninterrupted pattern.
Regulation of Ventilation
The body maintains ventilation by monitoring levels of carbon dioxide (CO2), oxygen (O2), and hydrogen ion concentration (pH) in the arterial blood. Among these factors, the level of CO2 plays a crucial...
01:21Acute 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:
The underlying physiological abnormalities that contribute to hypoxemic respiratory failure include:
01:29Acute Respiratory Failure-V
The treatment for acute respiratory failure varies based on factors like the underlying cause, overall health, and severity. A collaborative healthcare team is essential for early detection, often through arterial blood gas analysis. Identifying the cause is the primary goal, with treatment strategies adjusted for ventilation/perfusion (V/Q) mismatch, shunting, or diffusion impairment.
Ensure that patients are monitored continuously for their response to therapy, including changes in...
Ensure that patients are monitored continuously for their response to therapy, including changes in...
01:26Oxygen Delivering System I: Nasal Cannula and Face Mask
The human body requires oxygen to function, and when the natural process of respiration is hindered, external devices, including the following, are needed to help deliver this vital gas.
Nasal Cannula
A nasal cannula is a lightweight tube split at one end into two prongs and placed in the nostrils. It is typically used to deliver low to medium levels of oxygen.
Suggested flow rate: The suggested flow rate for a nasal cannula typically ranges between 1 and 6 L/min.
Oxygen percentage setting:...
Nasal Cannula
A nasal cannula is a lightweight tube split at one end into two prongs and placed in the nostrils. It is typically used to deliver low to medium levels of oxygen.
Suggested flow rate: The suggested flow rate for a nasal cannula typically ranges between 1 and 6 L/min.
Oxygen percentage setting:...
01:16Oxygen Delivering System II: Venturi Mask and Transtracheal Oxygen
Oxygen therapy is a pivotal aspect of medical care, particularly for patients with respiratory ailments. Two prominent oxygen-delivering systems include the Venturi mask and the transtracheal oxygen catheter.
Venturi Mask
The Venturi mask, named after the Venturi effect, is designed to deliver precise oxygen concentrations. It consists of a large tube with an oxygen inlet that narrows down, causing a pressure drop that pulls air in through adjustable side ports. The mask is a lightweight,...
Venturi Mask
The Venturi mask, named after the Venturi effect, is designed to deliver precise oxygen concentrations. It consists of a large tube with an oxygen inlet that narrows down, causing a pressure drop that pulls air in through adjustable side ports. The mask is a lightweight,...