NEUROLOGY CORNER

 

Richard Belli, D.C.

 

Respiration, Chronic Rib Fixations and Zinc

 

We have all seen patients that have been treated by other practitioners for mid and upper back pain that is temporarily relieved by manipulation, then comes back after a day or two. Chronic rib fixations are often the result of dysfunction of the respiratory centers in the brain stem. Additionally, zinc is vitally important for normal function of the brain stem respiratory centers. Zinc deficiencies are common because of high carbohydrate and fast food consumption. This, in combination with a zinc depleted food supply, is a sure recipe for deficiency and respiratory dysfunction. As a matter of fact, for every molecule of insulin produced, the pancreas needs four molecules of zinc.

 

Respiration is a complex physiological process that is primarily driven by the stimulation of a chemosensitive area in the ventral aspect of the medulla by hydrogen ions (H+). As a matter of fact it is thought that H+ may be the only direct stimulus to the chemosensitive area. The chemosensitive area projects to the dorsal respiratory group in the medulla, stimulating respiration. The dorsal respiratory group also receives afferent input from the nucleus solitarius which receives projections from cranial nerves IX and X. These afferents come from stretch receptors in the lungs, carotid bodies and the aortic arch. There is also mechanoreceptor input form the intercostal muscles and the costosternal and costovertebral joints. All of these inputs are necessary for normal respiration.

 

The blood brain barrier and the blood cerebrospinal barrier are pretty much impermeable to H+, consequently the H+ needed to stimulate respiration is derived from a source within the interstitial fluid of the medulla and CSF. Even though carbon dioxide does not have a strong direct effect on respiration it has a very powerful indirect effect. The blood brain barrier and blood CSF barrier is completely permeable to carbon dioxide. Therefore respiration is directly regulated by blood carbon dioxide levels. As blood carbon dioxide increased, so does the carbon dioxide levels of the interstitial fluid of the medulla and the cerebrospinal fluid.

 

Carbon dioxide in the cerebrospinal fluid and the interstitial fluid of the medulla react with water to form carbonic acid, the carbonic acid dissociates into H+ and bicarbonate ions. This reaction provides the H+ necessary to stimulate the chemosensitive center, which stimulates the inspiratory area. The chemical reaction between carbon dioxide and water depends on carbonic anhydrase as a catalyst. Carbonic anhydrase is a zinc dependent enzyme. That makes the necessity of zinc for respiration obvious.

 

The chemosensitive and respiratory centers are bilateral. If one side dysfunctions more than the other, there will be incoordination of the respiratory mechanism and consequent dyskinetic muscles and fixations. The fixations should be treated with coupled reduction and fast‑stretch modalities and the patient should be tested for zinc deficiency.