To continue on from yesterday’s post, Dr Ghanem replied promptly to my request for more information on his G Tube;
The G tube is a tube with narrow orifice and holes in its wall built on a scale to the capillary tube. It was designed and invented by me 39 years ago. It was later professionally made for me by a Designer engineer Mr Peter Holder of Eastbourne who provided an endless supply of G tubes free of charge before 1985… The G tube I used had a diameter of 7 mm with an orifice of 5 mm with multiple small holes in its wall.
Charles Michel tells me he recalls a conversation between two famous pioneers of microcirculation physiology;
A nice calculation of this effect (Bernoulli effect) was given by Landis in response to a question raised in discussion by Zweifach at a symposium in the early 1960’s.
Which is a nice confirmation of my theory that Knowledge has a 25 year life cycle. Ghanem was not to know that a Bernoulli effect in microcirculatory haemodynamics had been considered years earlier. The University of California San Diego has a copy of every paper Professor Benjamin Zweifach presented or published between 1933 and 1998 and it is possible that Charles was present at Zweifach, B. W.: Current Concepts of Microcirculatory Behavior. 3rd Europ. Conf. Microcirculation (Jerusalem 1964), also in Bibl. Anat. 7 (1965), 2-8. (Karger/Basel/New York). Eugene M. Landis was one of the first physiologists to measure capillary pressure and permeability.
These days we can of course watch capillary blood flow to see if there is any evidence of a Bernoulli effect at play.
Michel recalls that “the fluid velocities in [Ghanem’s] “arterial” section necessary to generate such low pressures at the pores in the vessel walls are far too high for those found in the microcirculation.” What do you think?