Effect of initial gas bubble composition on detection of inducible intrapulmonary arteriovenous shunt during exercise in normoxia, hypoxia or hyperoxia.
Summary of "Effect of initial gas bubble composition on detection of inducible intrapulmonary arteriovenous shunt during exercise in normoxia, hypoxia or hyperoxia."
Concern has been raised that altering the fraction of inspired O(2) (FIO(2)) could accelerate or decelerate microbubble dissolution time within the pulmonary vasculature and thereby invalidate the ability of saline contrast echocardiography to detect intrapulmonary arteriovenous shunt in subjects breathing low or high oxygen gas mixtures. The current study determined if the gaseous component used for saline contrast echocardiography affects the detection of exercise-induced intrapulmonary arteriovenous shunt under varying FIO(2)'s. Twelve healthy human subjects (6 female) performed three, 11 min bouts of cycle ergometer exercise at 60% VO(2peak), in normoxia, hypoxia (FIO(2) = 0.14), and hyperoxia (FIO(2) = 1.0). Five different gases were used to create saline contrast microbubbles using two separate methods and were injected intravenously in the following order at 2 min intervals: room air, 100% N(2), 100% O(2), 100% CO(2) and 100% He. Breathing hyperoxia prevented exercise-induced intrapulmonary arteriovenous shunt whereas breathing hypoxia and normoxia resulted in a significant level of exercise-induced intrapulmonary arteriovenous shunt. During exercise, for any FIO(2), there was no significant difference in bubble score when using the different microbubble gas compositions made with either method. The current results support our previous work using saline contrast echocardiography and validate the use of room air as the gaseous component of saline contrast microbubbles to detect intrapulmonary arteriovenous shunt during exercise or at rest with subjects breathing any FIO(2). These results suggest that in vivo gas bubbles are less susceptible to changes in the ambient external environment than previously suspected.
1University of Oregon.
This article was published in the following journal.
Name: Journal of applied physiology (Bethesda, Md. : 1985)
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/20847134
- DOI: http://dx.doi.org/10.1152/japplphysiol.00145.2010
Medical and Biotech [MESH] Definitions
Intracranial Arteriovenous Malformations
Congenital vascular anomalies in the brain characterized by direct communication between an artery and a vein without passing through the CAPILLARIES. The locations and size of the shunts determine the symptoms including HEADACHES; SEIZURES; STROKE; INTRACRANIAL HEMORRHAGES; mass effect; and vascular steal effect.
A vessel that directly interconnects an artery and a vein, and that acts as a shunt to bypass the capillary bed. Not to be confused with surgical anastomosis, nor with arteriovenous fistula.
Substance Abuse Detection
Detection of drugs that have been abused, overused, or misused, including legal and illegal drugs. Urine screening is the usual method of detection.
An effect usually, but not necessarily, beneficial that is attributable to an expectation that the regimen will have an effect, i.e., the effect is due to the power of suggestion.
An abnormal direct communication between an artery and a vein without passing through the CAPILLARIES. An A-V fistula usually leads to the formation of a dilated sac-like connection, arteriovenous aneurysm. The locations and size of the shunts determine the degree of effects on the cardiovascular functions such as BLOOD PRESSURE and HEART RATE.
Through the enhanced photothermal effect, which was achieved using a silver film, a low power weakly focused continuous-wave laser (532 nm) was applied to create a vapor bubble. A convective flow was...
BACKGROUND: Early intrapulmonary recurrence is a major problem after pulmonary metastasectomy related to colorectal cancer. However, the risk factors for early intrapulmonary recurrence are not clear....
Single bubble feels the pressure: Sonochemical luminescence has been detected in a single-cavitation bubble within a narrow pressure domain below the sonoluminescence threshold. The parameter space of...
We experimentally study the dissolution of carbon dioxide bubbles into common liquids (water, ethanol, and methanol) using microfluidic devices. Elongated bubbles are individually produced using a hyd...
A 44-year-old woman was referred to our centre for interventional cardiac catheterisation. The diagnostic work-up after a preceding ischaemic stroke led to the assumption of a patent foramen ovale due...
The purpose of the study is to evaluate agitated saline versus polygeline for detection of intrapulmonary vasodilatation in patients with cirrhosis.
Inflammatory reaction in different compartments of the body may have a negative effect on outcome. This study assesses the inflammatory reaction systemically, intrapulmonary and intrapleur...
The objective of this study is to evaluate whether CPAP delivered by bubble CPAP resulted in a greater proportion of infants being successfully extubated when compared with management with...
The purpose of this study is to determine whether Thalidomide is effective in the treatment of arteriovenous malformations in the gastrointestinal tract.
During caesarean section, transient respiratory distress which occurs frequently (3%) with possible complications are at present managed by non invasive nasal continuous positive airway pr...