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Updated: Jun 18, 2026

Esophageal Heat Transfer for Patient Temperature Control and Targeted Temperature Management
Published on: November 21, 2017
Nosehouse: heat-conserving ventilators based on nasal counterflow exchangers
1Department of Biology, Duke University, Box 90338, Durham, NC 27708, USA. svogel@duke.edu
Abstract:
Small birds and mammals commonly minimize respiratory heat loss with reciprocating counterflow exchangers in their nasal passageways. These animals extract heat from the air in an exhalation to warm those passageways and then use that heat to warm the subsequent inhalation. Although the near-constant volume of buildings precludes direct application of the device, a pair of such exchangers located remotely from each other circumvents that problem. A very simple and crudely constructed small-scale physical model of the device worked well enough as a heat conserver to suggest utility as a ventilator for buildings.
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