Amputations in the Diabetic Patient

- See:
      - diabetic foot menu 
      - amputation menu 
      - osteomyelitis in the diabetic patient

- Discussion:
    - amputation should be considered for any diabetic patient w/ advanced changes (Charcot joints, multiple ulcers,  vascular pathology) who has who has undergone a surgical debridement which could not logically leave the patient w/ a functional foot;
    - vascular considerations:
           - exam:
                  - it is essential to distinguish between proximal and distal vascular lesions, since distal vascular lesions may be less amenable to arterial bypass (this statement is restricted to the diabetic patient w/ ischemic ulcerations or osteomyelitis);
                  - if there is an iliac pulse but no popliteal pulse (proximal lesion) then the patient should under go a formal vascular work up (since vascular bypass may be possible);
                  - if there is a popliteal pulse but no DP or PT pulse (distal lesion), then it is less likely that a vascular bypass will be successful);
                        - these patients should still have a vascular workup;
           - doppler ABI:
                  - in most cases, serves no useful role in the management of diabetic feet;
                  - the loss of compliance of the diabetic vessels will falsely elevate ABI readings, (which may falsely indicate that the diabetic foot is well perfused);
                  - references:
                        - Arterial systolic pressures in critical ischemia.
                        - Prognostic value of systolic ankle and toe blood pressure levels in outcome of diabetic foot ulcer
                        - Transcutaneous Doppler ultrasound in the prediction of healing and the selection of surgical level for dysvascular lesions of the toes and forefoot.
                        - Doppler-determined segmental pressures and wound-healing in amputations for vascular disease.
                        - An index of healing in below-knee amputation: leg blood pressure by Doppler ultrasound.
           - transcutaneous O2:
                  - references:
                        - Transcutaneous oxygen as a predictor of wound healing in amputations of the foot and ankle.
                        - Segmental transcutaneous measurements of PO2 in patients requiring below the-knee amputation for peripheral vascular insufficiency.
                        - Transcutaneous oxygen tension measurement in peripheral vascular disease.
                        - Transcutaneous oxygen and carbon dioxide pressure monitoring to determine severity of limb ischemia and to predict surgical outcome.

- Surgical Considerations:
    - often diabetic patients do not do well w/ transmetatarsal amputations, but this procedure may be indicated for wet gangrene involving the great toe and multiple lesser toes;
           - if there is any debate as to whether a distal foot amputation will heal, then the surgeon can start out w/ the distal amputation and can assess the adequacy of bleeding at that time;
    - needle test:
           - this can be used to help determine the level of amputation once the patient is under anesthesia;
           - prick the patient's thigh w/ a 20 gauge needle and assess the rate of bleeding;
           - then sequentially prick the patient's foot, ankle, and calf and compare the bleeding to the control;
    - patients with wet gangrene of the foot should be treated w/ open amputation just above or thru the ankle;
           - once the sepsis has cleared, a definative BKA can be performed;
           - it is generally a mistake to perform an open amputation at the same level as is planed for the definative amputation;
    - references:
           Simplified two-stage below-knee amputation for unsalvageable diabetic foot infections.
           Syme amputation in patients with severe diabetes mellitus

Lower-limb Amputations in Patients With Diabetes Mellitus

The diabetic foot: evolving technologies.

Management of the diabetic foot

Eikenella corrodens as a cause of osteomyelitis in the feet of diabetic patients. Report of three cases

One-stage versus two-stage amputation for wet gangrene of the lower extremity: a randomized study.

Diabetic foot infections. Bacteriologic analysis.

Simplified two-stage below-knee amputation for unsalvageable diabetic foot infections.

Long term prognosis after healed amputation in patients with diabetes.  

Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Tuesday, December 11, 2012 10:58 am