|
|
Rubicon Research Repository >
Rubicon Foundation Archive >
Undersea and Hyperbaric Medicine Journal >
Please use this identifier to cite or link to this item:
http://archive.rubicon-foundation.org/8041
|
| Title: | Cardiovascular aspects of glossopharyngeal insufflation and exsufflation. |
| Authors: | Novalija, J
Lindholm, P
Loring, SH
Diaz, E
Fox, JA
Ferrigno, M |
| Keywords: | DIVERS
DIVING
apnea
breath hold
breath-hold
glossopharyngeal breathing
lung capacity
glossopharyngeal insufflation
residual volume
glossopharyngeal exsufflation
blood pressure
cardiac output
Cardiovascular
human |
| Issue Date: | 2007 |
| Publisher: | Undersea and Hyperbaric Medical Society |
| Citation: | Undersea Hyperb Med. 2007 Nov-Dec;34(6):415-23. |
| Abstract: | Breath-hold divers use glossopharyngeal breathing to inhale above total lung capacity (glossopharyngeal insufflation, GI) or exhale below residual volume (glossopharyngeal exsufflation, GE). In these maneuvers, air is moved using glossopharyngeal rather than respiratory muscle activity. Four competitive divers performed several GI and GE maneuvers in sitting or standing position, while cardiovascular parameters were measured with a photoplethysmographic method; echocardiography was also performed during GE. During GI, the divers showed a 48% drop in mean arterial pressure (MAP) to 50 mmHg, with a 88% decrease in pulse pressure (PP), while heart rate (HR) increased by 36% to 103 beats/min and cardiac output (CO) dropped by 79% to 1.3 l/min. The increase in intrathoracic pressure during GI, measured in separate experiments, is probably responsible for these hemodynamic changes, by impeding venous return into the chest. Associated with the drop in MAP during GI were various neurological signs and symptoms, including dizziness, tunnel vision, involuntary twitching of facial muscles and one brief episode of loss of consciousness. During GE, initially MAP and PP increased by 36% and 61%, to 149 and 95 mmHg respectively; later HR decreased by 37% to 45 beats/min and CO dropped by 37% to 4.3 l/min. The early cardiovascular changes of GE may be related to a decrease in intrathoracic pressure, enhancing venous return, as shown by a 6 to 15% increase in end-diastolic diameter; later changes are similar to the responses to apnea at low lung volumes. Because of their hemodynamic effects, these breathing maneuvers should be performed with caution, particularly in the case of GI. |
| Description: | Undersea & Hyperbaric Medicine : Journal of the Undersea and Hyperbaric Medical Society, Inc. |
| URI: | http://archive.rubicon-foundation.org/8041 |
| ISBN: | 1066-2936 |
| Appears in Collections: | Undersea and Hyperbaric Medicine Journal
|
Files in This Item:
| File |
Description |
Size | Format |
|---|
| 18251438.pdf | | 1665Kb | Adobe PDF | View/Open |
|
All items in DSpace are protected by copyright, with all rights reserved.
|
