Concept
Diabetic foot, also known as diabetic gangrene, is one of the most serious chronic complications of diabetes and an important cause of disability and death in diabetes. Diabetic foot is caused by a variety of factors such as peripheral neuropathy, insufficient arterial blood supply to the lower limbs and bacterial infection in diabetic patients, which mainly manifests clinically as foot pain, deep skin ulcers and gangrene of the extremities.
Risk factors for the occurrence of diabetic foot
External factors: obesity, poor glycemic control, foot trauma, inappropriate foot care, alcohol abuse, smoking, and lack of knowledge about diabetes.
Internal factors: long duration of diabetes, combined renal and ocular pathology, vascular pathology, lower limb neuropathy, old age, foot deformity.
External factors can be controlled by the patient himself, but internal factors cannot, thus it is more important to focus on external factors.
Evaluation of diabetic foot
Neurological assessment
The main objective is to find out whether the patient still has protective nerve sensation. Method: Use a special 10g nylon wire, one end touches the patient’s big toe, and apply gentle pressure to bend the nylon wire just enough to make the patient’s sole and affected toe feel the nylon wire on the bottom of the foot at this time, then it is normal, otherwise it is abnormal. The test should avoid calluses, but should include areas prone to ulcers. The recommended measurement sites are the big toe and the metatarsal heads 1, 2, 3, 4, 5 and the heel and dorsum of the foot. If 10 points are measured and the patient feels only 8 points or less than 8 points, it is considered abnormal.
Skin temperature assessment
There are two types of temperature sensation measurement: qualitative and quantitative. Infrared skin thermometer can be used for quantitative measurement.
Pressure assessment
Pressure measurement can be helpful in the diagnosis of diabetic foot. Various testing systems have been developed, such as Mats Can system, Foots can system, etc. The principle is to let the subject stand on the plate with multi-point pressure sensitive device, or walk on the plate, through the scanner imaging transmitted to the computer, on the screen to display the color of different footprints, such as the red part is the main stress area, the blue part is the non-stress area, so as to understand whether the patient has foot pressure abnormalities. In case of pressure abnormalities, the basic principle of corrective treatment is to increase the contact area between the sole of the foot and the ground, minimize the pressure at the local pressure point, and avoid local pressure ulcers.
Assessment of the vascular system
Note the presence of hair loss or non-growth, pale skin, decreased skin temperature, prolonged venous filling time, slowed or absent pulse, edema, muscle atrophy, intermittent claudication and rest pain or nocturnal pain, and thickened or keratinized toenails on the foot. The simplest and most commonly used method to assess vascular lesions is the ankle artery to brachial artery blood pressure ratio (ABI), with normal values of 1.0-1.4; 0.8-0.9 for mild ischemia; 0.5-0.7 for moderate ischemia; and <0.5 for severe ischemia; those with severe ischemia are prone to lower extremity gangrene.
Wound assessment
Vagner classified the diabetic foot into 5 grades according to the severity of the lesion.
Grade 0: No open skin lesions. Exhibits high-risk foot manifestations such as inadequate blood supply to the extremity, skin bruising, purple-brown color, numbness, tingling and burning pain, dullness or loss of sensation, and deformity of the toes or foot.
Grade I: The skin of the extremity has open lesions, inflammation, blood blisters, frostbite or burns, etc. causing superficial skin ulcers, and the lesions have not spread to deep tissues.
Grade II: Infectious lesions have invaded deep muscle tissue. There is often cellulitis, multiple pus foci and sinus tract formation, but the tendons and ligaments are not yet destroyed.
Grade III: Tendon and ligament tissue destruction, cellulitis fusion forming large pus cavities, purulent secretions and necrotic tissue increase, but bone destruction is not yet obvious.
Grade IV: severe infection has caused bone defect, osteomyelitis, destruction of bone joints or has formed pseudo-joints.
Grade V: Infection or ischemia of a large portion of the foot or all of the foot. It leads to severe wet or dry necrosis with blackened corpse extremities, often affecting deep joints and the lower leg, and usually results in surgical high amputation.
TEXAS University classifies diabetic foot into 4 stages and 4 grades according to wound depth and the presence or absence of infection and ischemia; Grade 1: history of foot ulcer; Grade 2: superficial ulcer; Grade 3: ulcer deep to the tendon; Grade 4: ulcer involving the joint. 4 stages: A no infection, no ischemia; B combined infection; C combined ischemia; D combined infection and ischemia.
Prevention of diabetic foot
Strengthening foot examination
Once diagnosed, diabetic patients should insist on a comprehensive foot examination once a year to know whether there are neuropathy, vascular disease and musculoskeletal lesions, etc. Pay attention to ask the patient whether there is smoking, high blood pressure, high cholesterol, poor blood sugar control and any previous foot disorders, callus into ulcer formation, etc. If there are complications, the patient should be examined once a quarter. And actively treat complications and remove risk factors.
Effective blood sugar control
Good control of blood glucose is the most favorable measure to reduce the complications of diabetes, and glycated hemoglobin control within the normal range can reduce the occurrence of complications. Regular monitoring of blood glucose, adherence to long-term and appropriate hypoglycemic drug therapy, strict dietary control and good exercise therapy. We use insulin pump therapy to control blood glucose in a normal range in time, which is beneficial to the prevention and treatment of diabetic foot.
Actively prevent foot trauma
＊ Make it a habit to check your feet every day
＊ Quit smoking
§ Soak your feet in warm water every day, no more than 40?, and do not soak for too long
＊ Do not use hot water bags
§ Trim your toenails properly.
＊ Choice of shoes and socks
＊ Do not walk barefoot, wear shoes barefoot, and check for foreign objects in shoes before wearing them
* Correctly treat corns
＊ Keep skin clean and moist, prevent dryness and itching, and avoid scratching
Strengthen health education
A survey shows that most patients do not have a clear concept of diabetic foot and do not give effective care to the foot. They even did not go to the hospital for timely consultation. Therefore, it is important to strengthen education and raise patients’ awareness of self-protection. All diabetic patients should receive education on foot care and how to prevent diabetic foot, including enhancing the awareness of diabetic foot prevention, identifying sensory deficit and circulatory deficit; avoiding foot injury and foot wound care, in addition to controlling blood sugar well. Support from family and society should also be sought.
Treatment and care of foot ulcers
Relieve the pressure on the foot
Relieving the load of weight on the foot is an important factor in promoting ulcer healing. For patients who cannot stay in bed all day, the use of a type of shoe called a full-contact cast is considered the gold standard for the treatment of neuropathic ulcers. Others such as therapeutic orthopedic shoes, decompression shoes, and splints can also be helpful in reducing pressure on the foot.
Appropriate use of antibiotics
Bacterial cultures and drug sensitivity tests should be done on trauma secretions after the patient is admitted to the hospital. Xu Qi reported that the initial stage of infection often requires systemic medication, and early, adequate, and efficient combination of antibiotics to control infection is the key to treating this disease. o’meara reviewed the results of 30 studies reported in the literature and available in electronic databases. The importance of topical medication is emphasized. Oral or intravenous antibiotic therapy may be considered only in acute infections and before deep fistulas.
Different care options for different foot ulcers
The use of herbs, growth factors, and special dressings can promote wound healing. Shi Yixian reported that hyperbaric oxygen chamber treatment and Jiang Qixia reported that insulin wet dressing was effective for chronic ulcers. Compared with saline gauze, porous semi-permeable dressing can promote wound healing, shorten the treatment time and reduce the ulcer area. Mtller reported that chronic diabetic lower extremity ulcers could be cured with recombinant human platelet-derived growth factor-BB. Topical dressing exchange or growth factor helps to reduce the wound healing time, decrease the incidence of infection and amputation rate, and improve the quality of life.
In conclusion, the incidence of diabetic foot is increasing and is threatening human health and quality of life. We must pay attention to health education to control external factors to prevent or reduce the occurrence of diabetic foot; strengthen nursing care to promote ulcer healing to reduce amputation, reduce the burden of society and family, and improve quality of life.