= Louis Agassiz Shaw Jr.
{c}
= Louis A. Shaw
{c}
{synonym}
\b[<Louis A. Shaw>], identified in Harvard's institutional timeline as \b[Louis Agassiz Shaw, Jr.], coauthored the early tank-respirator reports with <Philip Drinker>.<A timeline of Harvard’s history by Harvard University>[1928 entry naming Drinker and Louis Agassiz Shaw, Jr., at the School of Public Health]{ref} Their apparatus applied changing <pressure> around the body while the head remained outside, implementing <negative-pressure ventilation> rather than requiring the same <pressure> change at the airway.
The second 1929 report, led in the published byline by Shaw, adapted the apparatus for small children and infants. It describes a metal enclosure, rubber neck collar, pump and valve arrangement, with a window for observation. Importantly, the report said the new apparatus had not yet been available for clinical use and cited laboratory tests on curarized cats. Those statements distinguish a reported experimental test from demonstrated clinical outcomes in the intended population.<An apparatus for the prolonged administration of artificial respiration: II. A design for small children and infants with an appliance for the administration of oxygen and carbon dioxide by Louis A. Shaw and Philip Drinker>[Printed pp. 33–35: introductory qualification, enclosure and neck seal]{ref}
A chamber seal is part of the mechanism. An original steady leakage model lets $P$ be suction magnitude relative to room <pressure>, $G$ the chamber-leak conductance and $Q_p$ the pump's extraction <volumetric flow rate> over the modeled operating range. If leakage is linear,
$$
Q_{\rm leak}=GP,\qquad P=\frac{Q_p}{G}
$$
at steady state. With hypothetical $Q_p=5$ L/s and $G=0.5\,\mathrm{L\,s^{-1}(cm\,H_2O)^{-1}}$, suction is 10 cm H$_2$O. Doubling the leak conductance at the same extraction rate reduces it to 5 cm H$_2$O. These are illustrative values, not apparatus specifications from the report.
This <chamber-leak sensitivity in negative-pressure ventilation> separates chamber pumping from pulmonary ventilation. Pumped air through a leaking enclosure is not automatically air passing through the subject's <airway>. In a further ideal passive <mechanical equilibrium> model with total <respiratory-system compliance> 0.01 L/(cm H$_2$O), those two driving <pressures> would produce added <volumes> 0.10 and 0.05 L. Measuring pump operation alone does not establish delivered lung <volume>.
The historical research therefore joined physiological reasoning with enclosure geometry, sealing and observation. A successful mechanical cycle tests that the apparatus changes its <boundary conditions>; independent physiological measurements are needed to establish what breathing assistance those changes provide.
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