Edema

Doctors define edema as an increase in the volume of fluid in the spaces between the body's cells. Depending on its cause, edema-related swelling may occur in a specific area or it may be distributed throughout the body.

There are many forms of edema. One type, known as anasarca, may be characterized by puffiness in the face. Other common signs of anasarca include rings that fit more snugly, or shoes that become uncomfortably tight, particularly in the evening. Another form of edema, ascites, is characterized by an excess of fluid in the lining of the abdomen and is usually associated with liver disease. Hydrothorax is yet another type of edema in which fluid accumulates in the space surrounding the lungs. Finally, idiopathic edema is a syndrome that occurs almost exclusively in women. It involves the retention of water and the accumulation of "water weight" as a part of premenstrual syndrome.

The causes of edema are related to the way fluids are distributed and transported throughout the body. Much of the fluid in the body is exchanged between the capillaries and the spaces that surround the cells. In a healthy state, a balance of pressure is maintained between the fluid in the capillaries and the fluid outside the capillaries, which is referred to as interstitial fluid. The development of edema occurs when this delicate balance of pressure is disrupted and an excess of fluid flows out of the capillaries and into the interstitial space.

Edema can also be caused by trauma to the systems that maintain a healthy balance of fluids in the body. For instance, burns, cuts, bumps, and bruises can damage the sensitive capillary tissues that control the flow of pressure into and out of the spaces between cells. The swelling that occurs as a result of these wounds is a form of edema. Chemical and bacterial invaders can damage the capillaries and trigger edema as well.

Other forms of edema are often caused by a reduction in the total volume of blood in the body. In this situation, the body compensates for the lower blood volume by retaining more water and salt. If, however, this response is insufficient to restore a proper blood volume, the retention of water and salt increases and edema can develop. This cycle is often seen in patients with congestive heart failure. In this case, the heart is unable to pump enough blood out of the heart and fill the circulatory system. The body then responds to the reduction in blood volume by retaining more and more water. Edema often follows.

Still more causes of edema include kidney failure, protein deficiency, and pregnancy, as well as the use of certain estrogen therapies and vasodilators.

Yang treated 20 cases of idiopathic edema with acupuncture. The acupoints were selected for treatment as follows: for edema due to qi stagnation and blood stasis, acupoints He Gu (LI4), Nei Guan (P6), Tan Zhong (Ren17), Tai Chong (Liv3), San Yin Jiao (Sp 6), Xue Hai (Sp10), Shui Fen (Ren 9), Yin Ling Quan (Sp 9), and Zu San Li (S 36) were selected; for edema due to conjoint invasion of pathogenic wind-dampness, acupoints Feng Fu (Du16), Feng Chi (G20), Feng Shi (G31), Yin Ling Quan (Sp 9), Zu San Li (S36), Zhong Wan (Ren12), San Yin Jiao (Sp 6), and Yang Ling Quan (Du3) were selected; for edema caused by water retention due to hypofunction of the spleen, acupoints Nei Guan (P6), Zhong Wan (Ren12), Zhang Men (Liv13), Zu San Li (S36), Yin Ling Quan (Sp9), San Yin Jiao (Sp6), and Nei Ting (S44) were selected. After the acupoints were needled, infrared radiation was applied for 30 minutes, followed by cupping. The results of this treatment were: 16 cases greatly improved, and the remaining 4 had improved.(8)

Han treated 58 cases of edema during menstruation with acupuncture. For edema with insufficiency of both the spleen and the kidney, suspended moxibustion was applied on acupoints Pi Shu (B20), Tong Tian (UB7), Guan Yuan (Ren4), and Ming Men (Du4) for 50 minutes, and 10 sessions constituted one course of treatment. For edema due to qi stagnation and blood stasis, acupuncture was applied on acupoints Qi Hai (Ren6), Xue Hai (Sp10), San Yin Jiao (Sp6), and Yao Yang Huan (Du3) daily for 30 minutes, and seven sessions constituted one course of treatment. The results from this treatment were as follows: 38 patients significantly improved, 17 improved, and the remaining 3 did not respond to the treatment.(9)

Zhao treated 36 cases of edema during pregnancy with acupuncture. The following acupoints were chosen: Yin Ling Quan (Sp9), Zu San Li (S36), Pi Shu (B20), and Shen Shu (B23). If there was excessive water, acupoints Shui Fen (Ren9), Fu Liu (K7), and San Yin Jiao (Sp6) were added. If there was significant stagnation of qi, acupoints Qi Hai (Ren6), San Jiao Shu (B22), and Tai Chong (Liv3) were added. This treatment was applied once a day. 5 times comprised one course of treatment. The main Chinese herbal formula used was Quan Sheng Bai Zhu San. If the skin in the affected area was hardened, Tian Xian Teng San (Powder of Caulis Aristolochiae) was added. The results showed that among the 36 cases, 8 cases had a marked improvement, 20 cases had improved and 8 cases had no effect. Among the treated cases, 3 cases were treated simply with acupuncture (1 case had significantly improved and 2 had improved slightly), 17 were treated with acupuncture combined with Chinese drugs (3 cases improved significantly 12 had improved slightly, and 2 cases showed no effects). Ordinarily, treatment effects are obtained after 5 applications of acupuncture.(10)