Fink effect
 | This article may be confusing or unclear to readers. (February 2021) |
The Fink effect, also known as "diffusion
or the "second gas effect",[3] is a factor that influences thefluids rapidly. This leads to a temporary increase[clarification needed] in both the concentrations and partial pressures of oxygen and carbon dioxide
in the alveoli.
The effect is named after Bernard Raymond Fink (1914–2000), whose 1955 paper first explained it.[1][4] When a patient is recovering from N2O
hypoxia, especially if the patient hypoventilates (which allows more time for evolving nitrous to dilute alveolar oxygen each breath).[5]
Nonetheless, this effect only lasts a couple of minutes and hypoxia can be avoided by increasing the fractional inspired oxygen concentration when recovering from N2O administration.[6]
It is for this reason that Entonox, a 50:50 gaseous mixture of nitrous oxide and oxygen, is suitable for use by para-medical staff such as ambulance officers: it provides sufficient nitrous oxide for pain relief with sufficient oxygen to avoid hypoxia.[7][8]
See also
- Concentration effect – Effect affecting the pulmonary alveolar gas concentration during anesthesia
- Inhalational anesthetic – Volatile or gaseous anesthetic compound delivered by inhalation
- Second gas effect – Effect occurring during general anesthesia
References
- ^ a b
J. Roger Maltby (2002). Notable Names in Anaesthesia. ISBN 978-1-85315-512-3.
- ^
S. Ahanatha Pillai (2007). Understanding Anaesthesiology. ISBN 978-81-8448-169-3.
- ^
Steven M. Yentis; Nicholas P. Hirsch; Gary B. Smith (2009). Anaesthesia and Intensive Care A–Z: An Encyclopedia of Principles and Practice. ISBN 978-0-443-06785-3.
- ^
PMID 13238868.
- ^
S. EINARSSON (1993). "Nitrous Oxide Elimination and Diffusion Hypoxia During Normo- and Hypoventilation". British Journal of Anaesthesia. 71 (2): 189–93. PMID 8123390.
- ^
Andrew B. Lumb; John F. Nunn (2005). Nunn's Applied Respiratory Physiology (6th ed.). ISBN 978-0-7506-8791-1.
- ^ "Entonox". AnaesthesiaUK (www.frca.co.uk). 26 January 2009. Archived from the original on 31 October 2007. Retrieved 27 February 2017.
- ^
Joanne D. Fisher; Simon N. Brown; Matthew W. Cooke (October 2006). UK Ambulance Service Clinical Practice Guidelines (2006) (PDF). Joint Royal Colleges Ambulance Liaison Committee. ISBN 1-84690-060-3. Archived(PDF) from the original on 5 June 2011. Retrieved 27 February 2018.
