Insensible perspiration

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Insensible perspiration is the loss of water through the skin which does not occur as perceivable sweat. Insensible perspiration takes place at an almost constant rate and reflects evaporative loss from the epithelial cells of the skin. [1] Unlike in sweating, the fluid lost is pure water, i.e. no solutes are lost. For this reason, it can also be referred to as "insensible water loss". [2]

The amount of water lost in this way is deemed to be approximately 400ml per day. [1] Some sources broaden the definition of insensible perspiration to include not only the water lost through the skin, but also the water lost through the epithelium of the respiratory tract, which is also approximately 400ml per day. [3]

Insensible perspiration is the main source of heat loss from the body, [4] with the figure being placed around 480 kCal per day, which is approximately 25% of basal heat production. [3] Insensible perspiration is not under regulatory control. [4]

History

Known in Latin as perspiratio insensibilis, [5] the concept was already known to Galen in ancient Greece and was studied by the Venetian Santorio Santorio, [6] who experimented on himself and observed that a significant part of the weight of what he ate and drank was not excreted in his faeces or urine but was also not being added to his body weight. He was able to measure the loss through a chair that he designed. [5]

Related Research Articles

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<span class="mw-page-title-main">Perspiration</span> Secretion of sweat from sudoriferous glands

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<span class="mw-page-title-main">Thermoregulation</span> Ability of an organism to keep its body temperature within certain boundaries

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<span class="mw-page-title-main">Iatrophysics</span> Medical application of physics

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References

  1. 1 2 Lote, Christopher J. (2012). Principles of renal physiology (5th ed.). New York, NY: Springer. p. 11. ISBN   978-1-4614-3785-7. OCLC   796995047.
  2. Brandis K. "Insensible Water Loss". anaesthesiamcq.com. Retrieved 6 August 2020.
  3. 1 2 Brandis, Kerry. "Fluid Physiology – 3.2 Insensible Water Loss". www.anaesthesiamcq.com.
  4. 1 2 "Insensible perspiration Definition and Examples – Biology Online Dictionary". Biology Articles, Tutorials & Dictionary Online. October 7, 2019.
  5. 1 2 Hollerbach, Teresa (June 11, 2018). "The Weighing Chair of Sanctorius Sanctorius: A Replica". NTM. 26 (2): 121–149. doi:10.1007/s00048-018-0193-z. PMC   5993855 . PMID   29761203.
  6. "Santorio Santorio (1561–1636): Medicina statica". Vaulted Treasures. University of Virginia, Claude Moore Health Sciences Library.