Diabetes is no stranger to everyone. With the improvement of living standards, the incidence of diabetes is on the rise significantly, and it has become one of the common diseases that endanger human health nowadays. The seriousness of diabetes is not in the diabetes itself, but in its complications. Vasculopathy due to diabetes is the basis for the formation of complications. The consequences of diabetes are severe if ulceration and necrosis of the lower extremities (diabetic gangrene for short) occurs, and some patients have to have their limbs amputated or even die. According to statistics, the incidence of diabetic gangrene is 53 times higher in men with diabetes than in non-diabetic patients, and 71 times higher in women. More than 40,000 people in the United States have their limbs amputated each year due to diabetic gangrene. Therefore, diabetic gangrene is a growing concern.
I. Etiology
1, large-vessel lesions
Diabetes is prone to atherosclerosis and causes macroangiopathy, leading to ischemia of the lower extremities.
2, microangiopathy
Diabetic patients are mostly associated with microcirculatory disorders.
3, infection
Infection is an important factor in the development of diabetic gangrene. Diabetic patients have a low immune system, making it easy to develop infections and difficult to control. Ischemic limbs are more susceptible to infection, which aggravates local ischemia and causes gangrene to occur.
4, neurological dysfunction
Diabetic patients have neurotrophic disorders and ischemic neuritis due to macroangiopathy and microangiopathy. Neurological dysfunction has a series of adverse effects on patients: abnormal diastolic function of blood vessels, abnormal opening of capillary traffic branches at the extremities, increased pressure, and diabetic burning foot. The foot is flushed, with increased skin temperature and self-reported burning-like pain, which is relieved when cooled, similar to the manifestation of erythematous limb pain. In other patients, ischemic neuritis is the main manifestation. They report burning pain in the foot, but the skin temperature is cool when touched instead of high, and they feel hot and painful but are afraid of cold.
Due to abnormal sympathetic nerve function, the secretion of sweat glands in the limbs is reduced, the skin is dry and easily cracked, so that the integrity of the skin is destroyed and easily combined with infection. Due to the abnormal function of sensory nerves, the sensitivity of the limb to pain is reduced or even lost, forming a painless diabetic foot. In addition, diabetes is easy to combine with eye disease and visual impairment, so that some patients are not aware of the trauma to the foot or even the formation of a large ulcer, and therefore cannot be diagnosed early.
In conclusion, the mechanism of development of diabetic gangrene is complex, and it can be considered that hyperglycemia is the key, macroangiopathy and microangiopathy are two important aspects, and neurological dysfunction is a characteristic comorbidity, and on this basis, if combined with infection, it will contribute to further aggravation of limb ischemia and cause diabetic gangrene.
II. Clinical manifestations
Diabetic limb ischemia has common features of general limb ischemic diseases, such as cold fear, pale skin, reduced blood flow, intermittent claudication, and nutritional disorders. It is unique in that it is a combination of the clinical manifestations of diabetes mellitus and multiorgan vascular complications, and in that the characteristic gangrene occurs later in life.
Staging of diabetic limb ischemia
The disease is generally clinically divided into four phases.
1. Phase I (preclinical)
This phase is characterized by the presence of atherosclerotic plaques already in the vessel wall leading to narrowing of the vessels, but the patient has no conscious symptoms.
2.Phase II (Ischemic compensatory phase)
This is the early stage of limb ischemia, and patients often just feel coldness in the limbs and occasionally have intermittent claudication. The difference with thrombo-occlusive vasculitis and atherosclerotic occlusive disease is that there are more obvious sensory abnormalities such as limb numbness in this period, which is a characteristic of diabetic limb ischemia, which is complicated by ischemic neuritis in the early stage.
3.The third stage (ischemic loss of compensation stage)
Patients in this stage may have obvious resting pain, pale or cyanotic limb skin color, obvious decrease in skin temperature and inability to walk. Some patients have cold limbs as the prominent manifestation, while limb pain sensation may be absent, forming diabetic painless feet.
4, the fourth stage (ischemic necrosis stage)
It is a serious manifestation of the disease and a major reason for patients to visit the clinic. Although it is the same as gangrene of the limb, the clinical manifestations are very different. The etiology can be divided into ischemic gangrene and infectious gangrene, and the clinical presentation is divided into dry gangrene and wet gangrene. The purpose of clinical typing is to facilitate targeted treatment.
Classification by nature of gangrene.
Diabetic foot gangrene is mostly wet gangrene due to severe infection. This is a characteristic of diabetic gangrene and a cause of high disability. Thus, the classification of wet gangrene, dry gangrene and mixed gangrene has been proposed.
1, wet gangrene: infection is the main cause, with more pus on the sore surface and more redness around the periphery.
2, dry gangrene: ischemia as the main cause, more than one or more toes of the part or all dehydrated dry, black necrosis, “mummy” shape.
3, mixed gangrene: combined infection on the basis of ischemic necrosis, both dry black necrotic parts, and more pus on the wounded side.
Attention should also be paid to severe gangrene due to diabetes combined with necrotizing fasciitis. Patients often develop redness of the skin of the foot after minor trauma to the foot or for no apparent reason, and it spreads quickly to the surrounding area, initially behaving similarly to dermatitis, but progressing very rapidly, often with grayish-white skin in the center of the original erythematous area after two or three days, with blisters, which flow out like flesh-washing liquid after breaking, and red hemorrhagic necrosis of the skin underneath. Sometimes gas can be produced under the skin, which is manifested by severe local pain, twisting sound on palpation, and foul-smelling gas escaping after incision. The pus is mostly grayish-black, mucopeptone-like and mixed with fatty particles. The odor is indescribably foul and will last a lifetime if smelled once. It is important to note that this type of gangrene is mainly due to infection, which spreads mainly along the fascia, with fascial necrosis occurring first, followed by skin necrosis, so that the seemingly normal subcutaneous fascia around the injured surface is often necrotic. However, except in severely ischemic limbs or toes, there is often extensive necrosis of the skin and subcutaneous tissue and late necrosis of the muscle layer. Therefore, it is important not to give up efforts to save the limb simply because of the extent of gangrene, because there is still hope for limb preservation in some cases through aggressive treatment as long as the systemic condition allows. We have saved many limbs with gangrene beyond the ankle joint and even the knee joint.
III. Treatment
Diabetic gangrene is complex and develops rapidly, so timely treatment is essential. Sometimes a foot can rot away in just a few days, or multiple ulcers can form, really “a hundred holes and a thousand sores”. Treatment of this disease should be based on the stage of the disease, the type of lesion and the patient’s general condition to choose a comprehensive treatment plan. To summarize, we should grasp the four links of controlling diabetes, preventing and controlling infection, improving blood circulation and treating peripheral nerve dysfunction.
The effectiveness of the treatment can be further improved by applying Chinese herbal medicine at different stages. Especially for the healing of late ulcerated sores, Chinese medicine treatment has its unique advantages. For dry gangrene, which is mainly ischemic, the corresponding surgical procedure can be chosen according to the situation as well as early improvement of blood supply. The efficacy can be further improved with the application of Chinese medicine at different stages of discriminatory treatment.
IV. Protection of diabetic ischemic limbs
Once diabetic patients develop limb ischemia or peripheral neuropathy, their quality of life will be affected, and ulcers and gangrene can occur with serious consequences if they are not careful. Active protection is the key to improving the quality of life. The following points should be noted.
1. Actively treat diabetes and stabilize blood sugar.
Many diabetic patients lack awareness of the prognosis in the early stage, can not adhere to the regular treatment, the application of hypoglycemic drugs intermittently, and more than long-term blood glucose monitoring, so that the blood glucose is not stable. Controlling diabetes and stabilizing blood glucose is the basis for preventing and treating its complications, and it is a long-term and arduous task to educate diabetic patients so that they can understand the relevant knowledge and actively cooperate with the treatment.
2. Prevention and treatment of atherosclerosis.
Diabetic patients are prone to atherosclerosis, which is the basis for the occurrence of limb ischemia in diabetic patients. Through active diet control, moderate physical activity with drug therapy can help prevent its occurrence and development.
3. Avoid limb trauma.
As a doctor, you should remind your patients that a diabetic patient may lose a limb or even his life because of an ill-fitting pair of shoes. Patients should always be alert to prevent any kind of trauma to the limb, including very minor burns. Even skin trauma that is insignificant to a normal person should be taken seriously and treated aggressively and correctly to prevent complications of infection that could lead to serious consequences.
In addition, strict prohibition of smoking and active prevention of microvascular and neurological lesions are equally important.