There are three fluid bodies that I address with my work: blood, lymph, and cerebral spinal fluid. Each has its own rhythm, its own constituents, its own function, and its own mechanism of action. Of these, blood is perhaps best understood.

Blood

Most people are familiar with the concept of arterial (red) blood carrying oxygen and nutrition to end organs in the body, and venous (blue) blood carrying carbon dioxide back to the lungs. The arteries and veins can suffer from problems with mobility that lead to damage to themselves (like aneurysm or varicosities) or surrounding tissue (like stroke or pelvic congestion syndrome). Manual medicine has strategies that can be helpful in addressing these systems.

The arterial system is a high pressure system. It can experience constraint due to internal or external factors. Internal factors that cause constraint are things like plaquing that can either cause a weakening of the arterial walls, or can cause the arterial blood not to be able to pass easily through the artery. The artery can also be plagued by external constraint such as fascial constrictions. Internal or external constraint can result in a bounding (pronounced) pulse or a sense of localized warmth. Dependent on your age and specifics of your situation imaging could be necessary to diagnose. Arteries carry blood away from the heart. So if there is a constraint, it is generally in the area of the bounding pulse or farther away from the heart

The venous system is a low pressure system. That is why when you get your blood drawn it is taken from a vein and not an artery. Most of my work focuses on the venous system because I primarily see congestion in my practice. Veins travel toward the heart. If there is congestion, the problem is closer to the heart than where the problematic vein is. In time if the underlying venous problem is not addressed, the valves in the veins will become incompetent and there will be a local component to the congestion also. In addition, some congenital conditions such as Erhlers Danlos could have more flaccid or patulous veins . If there is inadequate venous drainage, fluid will back up into the lymphatic system. That is why I always clear the lymphatics before the vascular system. Clear the lymphatics first and last.

Lymph

The lymphatic system has multiple components. The lymph nodes, appendix, thymus, and spleen are the lymph organs. Additionally there is a fluid lymphatic system. The fluid system of the lymph originates in the interstitial fluid in the tissue and carries fluid, protein, fat, fat soluble vitamins, lymphocytes, macrophages, waste and much more that has leaked out from the vascular system. About half of all circulating protein is in the lymphatic system. The lymphatic system is like a web that gently organizes into channels and networks always moving toward the heart. It runs parallel to the venous system, and on the way back to the heart drops off pathogens for lymph nodes to deal with.

The lymphatic system moves much more slowly than blood.  Lymph drains about four liters daily, while veins drain approximately five liters each moment. Like veins, lymph channels have valves. Lymph capillaries are much more leaky than blood capillaries. Unlike blood, lymph has no pump like the heart. Instead, there are tiny local pumps called lymphangions in parts of the lymph channels that pulse 5-8 times a minute. Lymph functions largely as a pressure gradient system and requires movement to move the fluid. The deep lymph (only 30% of all liquid lymph) is also pumped by exercise and movement. During exercise, the lymphatic drainage of the deep tissue increases by 5-15%. Proper physiologic breathing is another major way the lymph is stimulated. When you breathe in there is negative intrathoracic pressure. This ultimately causes lymph to be dumped into the subclavian veins.

The lymphatic system drains into the right and left subclavian veins at the thoracic outlet. The right lymphatic duct drains the right head, right arm, and right chest. The left subclavian vein drains the right chest, right arm, right head,  thoracic duct and part of the right chest. The thoracic duct carries all the lymph up from both lower extremities, the pelvis, and the abdomen. While all the lymph ultimately drains at the thoracic outlet, there are important transverse lymphatic watersheds. Lymphatic watersheds are areas that separate different regions of lymph and have few lymph collectors. Another way to think of a watershed is as a drainage basin. Lymph drains here, and then drains off in a different direction. The lower limb up to umbilical watershed drains into inguinal lymph nodes. The umbilical watershed to the clavicular watershed drains into the axillary lymph nodes. Finally, the head down to clavicle drains into neck lymph nodes. There is some degree of natural stasis here because there are few lymph collectors to mobilize the lymph. Interestingly the transverse watersheds correspond to the transverse planes that we are using to organize our discussion here.

Importantly, both the lymphatic and venous system take a long time to show symptoms after injury.

Cerebral Spinal Fluid

The last component of the fluid body that we will discuss is the cerebral spinal fluid. The cerebral spinal fluid is produced in the brain and circulates inside the meninges. The meninges surround the brain and the spinal cord, AKA the central nervous system. The meninges have three layers: the dura mater, the pia mater, and the arachnoid mater. We are primarily interested in the dura mater since we use it for treatment. The dura mater connects in the cranium, the upper cervical and the sacrum. You might be familiar with the dura if you got an epidural for birth. In that case your analgesia was injected into the space between the low back bones and the outer layer of the meninges called the dura.

The cerebral spinal fluid is produce in the choroid plexus and elsewhere in the brain. The pulse of the CSF appears to be related to a combination of influences including the arterial pulse and the respiratory rate. The CSF cushions the brain and is a filtration system carrying nutrients and waste materials. The CSF carries parts of your immune system including microglia, white blood cells, macrophages, dendritic cells, and lymphocytes and is absorbed into the lymphatic and venous system in part.

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