Footnotes / Blog
Not talking about the New York Jets football team here, but instead the more serious complication of diabetes and/or smoking. Gangrene is defined as the necrosis or dying of soft tissue secondary to hypoxia (lack of oxygen). All cells and tissue in the human body require oxygen to survive. Oxygen is primarily delivered via small blood vessels called capillaries. When these capillaries are damaged, or the vessels leading to them blocked, it leads to death of the surrounding tissues.
Diabetes and smoking are the leading causes of gangrene. The high sugar content in the blood as well as nicotine, causes hardening and calcium deposits to form on the walls of blood vessels. Overtime the blood vessels will complete seal off, allowing no blood to flow through. When this happens in the bigger vessels there are procedures such as angioplasty, stents and bypass’s that can be down to alleviate the problem. However, when this happens in the foot, its termed “microvascular disease”, and as of now there is no treatment or cure.
Gangrene in the foot is usually seen in the tips of the toes first, as this is the area with the smallest blood vessels. Most patients experience excruciating pain, that is only relieved by hanging there leg of the edge of the bed. This allows gravity to bring blood down to where its needed. At this point several tests are ordered to pinpoint the extent of the disease. The easiest test is called Non-invasive vascular studies that we do right in our office. It includes using a doppler machine to take measurements of the amount of blood flowing through the arteries of the thigh, leg, and foot. What the doppler does, it measures that sound created by blood flowing through an enclosed space. In a normal vessel one should here a tri-phasic pulse, which means 3 distinct sounds with each heart beat. Anything less is considered diseased.
The doppler test is also done inconjuction with an ABI, also known as a Ankle-Brachia-Index. In basic terms a blood pressure is placed on the forearm and another on the thigh, leg, or foot. A ratio is derived from the 2 different blood pressure readings, and this further helps in our diagnosis of peripheral vascular disease.
If there is adequate blood flow for healing, then usually the patient will need to undergo amputation of the gangrenous digit. Depending on how much patients blood flow is available for healing, only part of the digit may need to be removed, or if the foot is severely diseased more will need to be removed.