Intrapulmonary and intracardiac shunting with exercise at altitude

Wilderness & Environmental Medicine
Chris H E ImrayBirmingham Medical Research Expeditionary Society

Abstract

Recent studies in normal participants have shown that right to left shunt blood vessels in the lung open up during exercise. We describe the first field study to investigate this phenomenon at altitude. This study aimed to assess the effect of altitude and partial acclimatization on inducible right to left shunting at rest and with exercise. A contrast-enhanced transcranial Doppler imaging technique to detect microbubbles after injection of blood and saline agitated with air was used to measure right to left shunting in 10 normal participants at rest and immediately after exercising to maximum oxygen consumption (VO(2max)) at 80 m, on acute exposure to 3450 m, and finally after a week above 3450 m. At 80 m, exercising resulted in right to left shunting via patent foramen ovale in 2 participants, but there was no evidence of shunting in the remaining 8 participants. Cerebral microbubbles were detected at rest in the 2 participants with patent foramen ovale on acute exposure to 3450 m, and the shunting increased on exercise (P = .04). In 5 of the remaining 8 participants without patent foramen ovale, cerebral microbubbles were detected on exercise (P = .04) but not at rest. Partial acclimatization had minimal effect on the preval...Continue Reading

References

Jan 1, 1982·Ultrasound in Medicine & Biology·J Roelandt
Dec 14, 2001·The New England Journal of Medicine·J L MasUNKNOWN Patent Foramen Ovale and Atrial Septal Aneurysm Study Group
Apr 10, 2004·High Altitude Medicine & Biology·Paul G Firth, Hayrunnisa Bolay
Apr 27, 2004·Journal of Applied Physiology·Marlowe W EldridgeJohn S Hokanson
Jul 22, 2004·High Altitude Medicine & Biology·Buddha BasnyatJeffrey H Gertsch
Sep 25, 2004·The Journal of Physiology·Michael K SticklandRichard L Jones
May 28, 2005·Journal of Applied Physiology·C H E ImrayA D Wright

❮ Previous
Next ❯

Citations

Jun 19, 2012·Neurología : publicación oficial de la Sociedad Española de Neurología·F J Carod-Artal
Jan 24, 2009·Lancet Neurology·Mark H WilsonChris H Imray

❮ Previous
Next ❯

Software Mentioned

DWL QL Offline Analysis
StatView

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.