Related Experiment Video
Updated: Jul 10, 2026
Investigation into Deep Breathing through Measurement of Ventilatory Parameters and Observation of Breathing Patterns
Published on: September 16, 2019
Ventilatory gas analysis in SCUBA divers using a surface-based measurement system
R L Jones1, D Docherty, C A Gaul
1Department of Medicine, University of Alberta.
Abstract:
The main technological problem associated with measuring gas exchange in submerged divers breathing from a self-contained underwater breathing apparatus (SCUBA) involves simulating ambient water pressure on the expired side of the SCUBA regulator without causing regulator free-flow. This report presents a method to acquire expired gas from exercising divers for analysis at the surface using a standard metabolic measurement system. We did this using a flat collapsible tube downstream from the expiration valve of the regulator. We tested 12 divers while swimming on the surface and during SCUBA at 1.8 m (6 ft) underwater using a tethered swim/counter weight system to provide graded exercise to exhaustion. Peak minute ventilation was not significantly different between surface swimming and SCUBA, but peak oxygen consumption (VO2) was lower (p < 0.0001) during SCUBA than for surface swimming. There was a significant correlation (p = 0.0002) between peak VO2 during SCUBA and surface swimming. These results show that VO2 and ventilation can be accurately measured in SCUBA divers during underwater exercise and the new and simple technique will be useful to those interested in the energy requirements of diving activities in shallow water.
More Related Videos
Related Concept Videos
01:16Oxygen Delivering System II: Venturi Mask and Transtracheal Oxygen
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,...
01:17Assessment of Diffusion and Perfusion
The Role of Diffusion in Respiration
Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration. In the respiratory system, this principle...
01:19Special considerations while measuring oxygen saturation
Ensuring accuracy in vital sign recordings while prioritizing patient comfort and minimizing anxiety is important.
01:29Assessment of Ventilation II: Respiratory Depth and Rhythm
Respiratory depth measures the volume of air inhaled or exhaled during a breath. It can vary from shallow to deep and typically remains consistent when a person is at rest or asleep. Occasionally, individuals will automatically inhale deeply, known as sighing, which inflates the lungs with more air than normal breathing.
To assess respiratory depth, observe the degree of chest excursion or movement:
01:26Blood Studies I: ABG and VBG
Arterial Blood Gas (ABG)
Arterial Blood Gas (ABG) studies are crucial for assessing the lungs' ability to supply oxygen and remove carbon dioxide, reflecting the patient's ventilation status. They also help understand the kidneys' capacity to reabsorb or...