There are 6 basic functions of Qi. It transforms, transports, holds,
raises, protects, and warms. Let's look a each of these in a little more
detail. I'll put astericks in front of the ones which are going to be
central to understanding the diffence between a diagnosis of Qi Deficiency
and Yang Deficiency.
Transforming: This refers to things like "Spleen_Qi trnsforms food into
Food-Qi, Kidney-Qi transforms fluids, BL_Qi transforms urine, Heart_Qi
transforms Food-Qi into Blood." (Maciocia, Foundations, p. 47) To clear
things up a little for those brand new to TCM, the Stomach "rots" and
"ripens" the food one eats, the Spleen extracts the Food Qi from this rotted
and ripened food and ....
Transportation: The Spleen transports the Food Qi that has been extracted
from the "rotted and ripened" food to the Lungs where it mixes with Air Qi
which the Lungs have extracted from the air breathed in. "Spleen-Qi
transports Food-Qi, Lung-Qi transports fluids to the skin, Kidney-Qi
transports Qi upwards, Liver-Qi transports Qi in all directions, Lung-Qi
transports Qi downward." (Maciocia, p. 17)
Holding: "Spleen-Qi holds the Blood in the blood vessels and fluids,
Kidney-Qi and Bladder-Qi hold urine, Lung-Qi holds sweat." (p. 47) There is
a TCM syndrome called Spleen Not Controlling Blood. This is a special form
of Spleen Qi Deficiency in which the emphasis is on the Qi function of
holding. In addition to the usual symptoms of Spleen Qi Deficiency, there
will be abnormal bleeding. There may be blood spots in the skin, blood in
the stools or urine, abnormal bleeding from the uterus, etc. Please not that
Spleen Not Controlling Blood is not the only possible Root of abnormal
bleeding. Hot Blood (another TCM syndrome) can be a Root of abnormal
bleeding as can be Blood Stasis. Hot Blood and Blood Stasis are Excess
problems (problems caused by there being too much of something); Spleen Not
Controlling Blood is a Deficiency state (problems caused by there not being
enough of something, in this case Spleen Qi). Abnormal bleeding can result
from either Deficiency or Excess causes.
One of the possible symptoms of Kidney Qi Deficiency or Bladder Qi
Deficiency is urinary incontinence. The person can't make it to the
bathroom in time and/or dribbles urine throughout the day. One of the
possible manifestations of Spleen Qi Deficiency is diarrhea. In both cases
the body isn't holding onto something when it should be. Note the part about
"Lung-Qi holds sweat". One of the main diagnostic criteria for Qi
Deficiency in general and Lung Qi Deficiency in particular is the person
sweats a lot - independently of temperature or activity. Again, something is
not being held onto when it should be held onto.
Raising: "Spleen-Qi raises the organs, Kidney-Qi rises upward." (p. 47)
There is a TCM syndrome called Spleen Qi Sinking. This is another special
case of Spleen Qi Deficiency. In this one the Qi function of raising is
messed up. The symptoms are those of Spleen Qi Deficiency plus prolapse of
Organs. Hemorrhoids and varicose veins may be due in part to Spleen Qi
Sinking. (Maciocia, Foundations, p. 244) Spleen Qi Sinking is classified as
a Deficiency syndrome; cases of rebellious Qi (Qi rising when it should be
descending) are classified as Excess problems.
Protecting: "Lung-Qi protects the body from exterior pathogenic factors."
(p. 47) We're talking a special form of Qi here called Protective (Wei) Qi.
When a person catches infections easily and/or is weather sensitive, this
can be a case of just Protective Qi Deficiency and Lung Qi Deficiency (in
the case of infections). Or, it can be a case of longstanding Yang
Warming: "This is a function of Yang-Qi. Both Spleen-Yang and Kidney-Yang,
especially the latter, have the function of warming the body."