Amputation is the removal of a limb (most commonly a toe, foot, leg, or arm); in modern medicine, amputation is a treatment of last resort.
In the United States and in the majority of developed countries, the most common reason for amputation is peripheral vascular disease, a circulatory problem often associated with diabetes and atherosclerosis.
Modern surgical techniques facilitate the use of sophisticated prosthetic devices, which have greatly improved the quality of life for patients who have undergone an amputation.
Human limbs include bones, tissues, and the blood vessels that supply them with oxygen and nutrients and remove carbon dioxide and other waste products. This blood vessel system (the circulatory system) is so extensive that normally no cell in the body is more than a few microns away from a blood vessel.
However, disease or traumatic injuries can impair the circulatory system, causing tissue death. In severe cases, amputation of the limb may be required.
WHEN IS IT INDICATED?
Currently, the following indications are associated with amputation:
Peripheral vascular disease; and
RISK FACTORS FOR POSSIBLE COMPLICATIONS
A complete health assessment is conducted prior to amputation to correct the following risk factors for possible complications:
Blood sugar abnormalities;
Use of bloodthinning medications; and
Allergies to anesthesia, pain medications, or antibiotics.
Determining the need for amputation often begins with clinical tests, including checking the patient for:
Unnaturally cool skin near the wound;
Extremely painful skin;
Visibly infected or non-healing skin ulcers or other wounds; or
The presence of pain at rest.
Imaging tests such as angiography and ultrasound allow the physicians to see whether blood is reaching a given area of the body. Blood pressure tests and treadmill tests may also be ordered.
Upon determining that amputation is necessary, the level of amputation required (how much of the affected limb requires removal) is determined using the following measures:
Sensory loss; and
Bleeding at an incision site.
Patients who are expected to use a prosthesis following amputation will be fitted, so that the prosthetic device will be available soon after the operation.
WHAT TO EXPECT
Basic principles of amputation involve choosing an incision site and removing the diseased limb while preserving as much healthy skin, blood vessel, and nerve tissue as possible.
During the operation, the patient is placed under general or spinal anesthesia and systems for monitoring heart rate, blood pressure, temperature, and brain function are put in place.
Then, the surgeon determines the level of amputation and incises the skin, making sure to leave enough healthy skin to cover the stump for easier healing and to keep the rough scar tissue away from pressure points of an eventual prosthesis.
The surgeon then proceeds through the muscle layer and divides nerves so that the cut ends retract below the end of the remaining bone. A tourniquet or other temporary closure is applied to minimize bleeding, and then the surgeon isolates and divides the healthy major blood vessels. Bony prominences are smoothed because uneven bone would make for a painful stump once fitted with a prosthesis.
Prior to finishing the amputation, the surgeon will release the tourniquet and determine that all bleeding points are clamped and coagulated (closed off). The care team may or may not then install temporary drains that will permit suction and drainage of blood and other fluids.
Upon completion of the removal of diseased tissue and the restructuring of healthy tissue, the surgeon can elect to leave the site open for 10 to 14 days (open flap amputation) or to close the flaps (closed amputation).
A stocking may be placed over the stump to hold drainage tubes and wound dressings in place, and the limb may be placed in traction.
POST-TREATMENT PROCEDURES AND GUIDELINES
Following amputation, patients are likely to remain in the hospital for at least 5 to 14 days. Pain medications and antibiotics are prescribed as needed. Patients with severe phantom limb pain or emotional concerns after surgery may undergo psychological counseling or drug therapy. Physical therapy is given almost immediately, and practice with a prosthetic device begins as early as possible, generally 10 to14 days after surgery.
The care team will monitor the patient's health as regards basic wound healing. Atherosclerosis, hydration, diabetes mellitus, malnutrition, infection, and other toxic states potentially could slow wound healing.
The most common complications are related to the patient's initial health or the degree of traumatic injury. However, a number of complications specific to the amputation may appear, including:
Contractures (a fixed deformity at the joint);
Hematoma (a bleeding blood vessel);
Necrosis (death of the skin flaps);
Gangrene (tissue death); and
Mortality, which ranges from 5 to 15 percent from amputations.