Do Patients with Critical Limb Ischaemia Undergo Multiple Amputations after Infrainguinal Bypass Surgery?

Pre-operative predictors of poor outcomes in patients undergoing surgical lower extremity revascularisation - Retrospective cohort study

BACKGROUND

Surgical lower extremity revascularisation (LER) can lead to poor outcomes that include delayed hospital discharge, in-hospital mortality, major amputations and readmissions. The aim of this study was to identify pre-operative predictors associated with these poor clinical outcomes.

MATERIALS AND METHODS

All patients (n = 635; mean age 69; male 67.4%) who underwent surgical LER over a 5 year period in a single tertiary vascular institution were identified. Patients considered to have suffered a poor outcome (Group A) included all in-hospital mortality and major amputations, delayed discharges with a length of stay (LOS) over one standard deviation above the mean or any readmission under any specialty within 12 months. Group A included 247 patients (38.9%) and the good outcome group included the remaining 388 patients (61.1%) from which a sample of 99 patients were selected as controls (Group B).

RESULTS

Mean LOS for the entire study group was 14.4 ± 17.5 days, 12 month readmission rate was 29.1% and in-hospital mortality and major amputation rate was 2.7% and 1.4%, respectively. Pre-admission residence other than own home (OR 9.0; 95% CI 1.2-70.1; P = 0.036), atherosclerotic disease burden (OR 2.2; 95% CI 1.3-3.8; P = 0.003) and tissue loss (OR 3.0; 95% CI 1.6-5.3; P < 0.001) were identified as independent, statistically significant pre-operative predictors of poor outcome. Following discharge, group B patients had a significantly higher rate of amputation free survival and graft infection free survival (P < 0.001) compared to group A.

CONCLUSION

Recognition of pre-operative predictors of poor outcome should inform case selection and identify high risk patients requiring intensive perioperative optimisation and post discharge follow up.

Incidence of ipsilateral postoperative deep venous thrombosis in the amputated lower extremity of patients with peripheral obstructive arterial disease

OBJECTIVE

Patients undergoing amputation of the lower limb due to peripheral arterial disease (PAD) are at risk of developing deep venous thrombosis (DVT). Few studies in the research literature report the incidence of DVT during the early postoperative period or the risk factors for the development of DVT in the amputation stump. This prospective study evaluated the incidence of DVT during the first 35 postoperative days in patients who had undergone amputation of the lower extremity due to PAD and its relation to comorbidities and death.

METHODS

Between September 2004 and March 2006, 56 patients (29 men), with a mean age of 67.25 years, underwent 62 amputations, comprising 36 below knee amputations (BKA) and 26 above knee amputations (AKA). Echo-Doppler scanning was performed preoperatively and on postoperative days 7 and 31 (approximately). All patients received acetylsalicylic acid (100 mg daily) preoperatively and postoperatively, but none received prophylactic anticoagulation.

RESULTS

DVT occurred in 25.8% of extremities with amputations (10 AKA and 6 BKA). The cumulative incidence in the 35-day postoperative period was 28% (Kaplan-Meier). There was a significant difference (P = .04) in the incidence of DVT between AKA (37.5%) and BKA (21.2%). Age >or=70 years (48.9% vs 16.8%, P = .021) was also a risk factor for DVT in the univariate analysis. Of the 16 cases, 14 (87.5%) were diagnosed during outpatient care. The time to discharge after amputation was averaged 6.11 days in-hospital stay (range, 1-56 days). One symptomatic nonfatal pulmonary embolism occurred in a patient already diagnosed with DVT. There was no relation between other comorbidities and DVT. The multivariate analysis showed no association between risk factors and the occurrence of DVT in the amputated extremity. DVT ipsilateral to the amputation did not influence the mortality rate (9.7%).

CONCLUSION

The incidence of DVT in the early postoperative period (<or=35 days) was elevated principally in patients aged >or=70 years and for AKA. Patients with PAD who have recently undergone major amputations should be considered at high risk for DVT, even after hospital discharge. Given the high rate of postoperative DVT observed in this study, we now recommend prophylactic anticoagulation for these patients, but further study is needed to determine the optimal duration and efficacy of this treatment.

Forefoot amputation with limb revascularization: the effects of amputation, timing, and wound closure on the peripheral vascular bypass graft site

BACKGROUND

Much has been written about the effects of successful arterial bypass on forefoot surgery for ulceration and gangrene. This study examined the effects of the amputation site and timing on the arterial bypass graft site.

METHODS

We reviewed the records of all patients who had successful vascular bypass graft surgery and amputation at our institution, between October, 1995 and May, 2002. Thirty-eight procedures in 35 patients fit the criteria and were included in the study.

RESULTS

Thirty-five patients had successful vascular bypass graft surgery and forefoot amputation for gangrene or nonhealing ulceration. Three of these patients developed gangrene on the contralateral side and received similar treatment for that side. All of the wounds eventually healed. Healing time, rate of graft infection, and rate of wound dehiscence did not differ noticeably between patients with amputation immediately after arterial bypass and patients with amputation one or more days after arterial bypass. Infection at the bypass site occurred in two patients; their amputation sites were closed primarily. Wound dehiscence developed at the bypass site in one patient whose amputation site was closed by secondary intention. Although not statistically significant, the median healing time in patients treated with primary closure (37 days) was less than that in patients treated with closure by secondary intention (61 days; p = 0.09), and rates of graft infection and wound dehiscence did not differ between these two groups of patients.

CONCLUSIONS

Amputation site wound closure may adversely affect the bypass graft, but results were not statistically significant. Treatment requires a closely coordinated team approach between the vascular surgeon and the orthopedic surgeon.