Blood shift
Encyclopedia
Blood shift has at least two separate meanings:
- In medicineMedicineMedicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....
, it is synonymous with left shiftLeft shiftLeft shift or blood shift is an increase in the number of immature leukocytes in the peripheral blood, particularly neutrophil band cells....
.
- In biologyBiologyBiology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines...
, it may refer to a phenomenon seen when mammalMammalMammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
s submerge in water. It is part of the mammalian diving reflexMammalian diving reflexThe mammalian diving reflex is a reflex in mammals which optimizes respiration to allow staying underwater for extended periods of time. It is exhibited strongly in aquatic mammals , but exists in a weaker version in other mammals, including humans. Diving birds, such as penguins, have a similar...
. Blood vessels in the extremities contract, leaving a higher percentage of the entire blood volume in the torso. An effect important for freedivers is the resulting widening of the lung'sLungThe lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...
capillariesCapillaryCapillaries are the smallest of a body's blood vessels and are parts of the microcirculation. They are only 1 cell thick. These microvessels, measuring 5-10 μm in diameter, connect arterioles and venules, and enable the exchange of water, oxygen, carbon dioxide, and many other nutrient and waste...
. It reduces the lung's residual volume, thus increasing the depth at which the residual volume is reached (untrained average is at about 30 meters). According to Yasemin DalkılıçYasemin DalkiliçYasemin Dalkılıç is a Turkish female free diver. She holds numerous world records in different categories of free diving. Though still in the middle of her career, she is already considered to be one of the all time greats in the sport....
, she can feel plasma enter her sinuses when diving to extreme depths whilst participating in free diving competitions. See also: immersion diuresisImmersion diuresisImmersion diuresis is a type of diuresis caused by immersion of the body in water . It is mainly caused by lower temperature and by pressure....