The cost effective management of diabetic foot infections is a challenge to the Canadian health system. The objective of this study was to predict preoperatively diabetic foot patients who will fail a transmetatarsal amputation (TMA) and end in a costly and disabling below knee amputation (BKA) and hence perform a primary BKA in select patients. Twenty-one patients failing TMA and revised to BKA within the first year were compared with a matched cohort of twenty-one successful TMA’s. The factors that were selected for comparison were: age at amputation, sex, smoking, type of DM, use of osetoset, presence of charcot fractures, previous contralateral surgery, previous debridement before TMA, debridement after TMA, dialysis, duration of ulcer prior to TMA, hemoglobin level at time of TMA, HbA1C, presence of heel ulcer, prior ipsilateral toe amputation, pulse status prior to TMA, vascular reconstruction and presence of unre-constructable vascular problem. Chi-square was done for group data, and ANOVA for numeric data. Long-term control of blood glucose level (HbA1C) was found to be significant in predicting the success of TMA. Need of debridement after TMA was found to be a significant predictor of failure of TMA. There was a trend towards duration of ulcer prior to TMA and smoking being significant. All other variables, including vascular status or renal failure were not significantly different between the two groups. As we have previously achieved a 75% success rate with TMAs in diabetics, we recommend a TMA as the first procedure in all diabetics with major forefoot infection or ulceration instead of a BKA. Obtaining good diabetic control in patients at risk for or requiring amputation for foot infection may prevent the TMA from failing and the subsequent need for BKA.
Patients were randomized between surgeon chosen pressure (control) and an automatically determined tourniquet pressure(study) group. Of the study group 94/106 (88.7%) had good to excellent fields compared to the control group where 100/132 (75.8%) had good to excellent fields (p<
0.05). In the study group, 5% failed to obtain an automatic pressure. Of the remainder, the average tourniquet pressure was 198 +/− 20.2 mHg compared to 259.6 +/− 4.4 mmHg for the control group (p<
0.0001). The automatic measurement of limb occlusion pressure resulted in better operative fields at a lower pressure. To compare the quality of the operative field that results from using an automatic limb occlusion pressure measurement (study group) versus the tourniquet cuff pressure chosen by the surgeon (control group). A module allowing rapid determination of tourniquet pressure from limb occlusion pressure was attached to a Zimmer ATS tourniquet machine. Using a coin toss, patients were randomized to the study or control groups. All patients underwent elective foot and ankle operations using a wide contoured tourniquet cuff. Of two hundred and forty-three patients, one hundred and twelve were assigned to the study (automatic) group and one hundred and thirty-two to the control (surgeon selected) group. Six patients (5.4%) failed to obtain a limb occlusion pressure measurement due to anatomical constraints (toe or thigh shape) or equipment problems, leaving one hundred and six in the study group. The average measurement time to determine limb occlusion pressure was 20 +/− 6 seconds. The mean tourniquet pressure for the study group was 198.5 +/−20.2 mmHg, and 259.6 +/−4.4 mmHg for the control group (p<
0.0001). Of the study group 94 (88.7%) had good to excellent fields compared to the control group where one hundred (75.8%) had good to excellent fields (p<
0.05). An automatically determined tourniquet pressure reduced the tourniquet pressure and improved the incidence of good to excellent operative fields compared to surgeon chosen pressures. The distribution curve of automatically determined tourniquet pressure indicates that 16% of patients will have a failed field if a standard pre-selected pressure of 250 mmHg is always chosen, in part explaining why pre-selected pressure may cause a poorer operative field.