This section addresses the concerns of the Western Clinical Herbalist related to medastro.
In medastro, we make distinctions between anatomical locations and physiological processes. The pulse quality tells us about the processes taking place in a given part of the body. The location on the pulse relates to a part of the body.
Rational for Using the Radial Artery
Whole systems views are intrinsic to medastro. The radial artery at the wrist provides a direct window into the lymph, cardio-vascular and nervous systems. For example, various stressors trigger the adrenal-medullary gland to secrete noradrenalin. This causes contraction of the capillaries and the pulse becomes tenser. If the acetylcholine secretion is higher than adrenalin the pulse will tend to yield beneath the finger (26). Also, pressing through tissues in order to gain contact with the radial artery provides information about the status of the lymph and the ground substance.
The pulse as an image of anatomy laid over the wrist is a further abstraction. It can be explained via holograms, self-replication and fractals. Self-replicating systems describes recurrent patterns that connect parts to the whole. From this view, the whole person may be observed at the level of the pulse. Likewise, a fractal is self-similar, in that the smaller pieces are reduced copies of the larger pieces. Some fractals are smaller and exact copies of the larger pieces. Most fractals are merely similar to the larger pieces, such as the branching pulmonary tracts or the vascular system (27, 28). These ideas provide a cognitive framework that allows for the radial artery at the wrist to represent the whole person.
The Function of the Blood Vessels
Vessels respond to the respiration of the lungs. Coordinated with the breath, the pulsing blood vessels spread throughout the body. The distribution of the vessels ensures local removal of waste and toxins, also perfusion of blood and nutrient supply through the capillary beds.
The cyclic interplay of nutrients and metabolites actively transport back and forth across cell membranes and the extracellular matrix. This creates a cellular rhythm or ”pulse” that forms the dynamic substrate for the physiological processes. These include electrical transmission and the alternating expansion and recoil of arteries lying near to the body’s surface. A further pressure wave generated by the ejection of blood from the left ventricle into the vascular system contributes to the pulse that can readily be felt.