Predictive factors of amputation in infra-inguinal vascular trauma: a monocentric experience

OBJECTIVES

Infra-inguinal vascular injuries (IIVI) are emergencies involving both functional and vital prognosis. The choice between saving the limb or doing a first-line amputation is difficult even for an experienced surgeon. The aims of this work are to analyze early outcomes in our center and to identify predictive factors for amputation.

M METHODS

Between 2010 and 2017, we reviewed retrospectively patients with IIVI. The main criteria for judgement were: primary, secondary and overall amputation. Two groups of potential risk factors of amputation were analyzed: Those related to the patient: age, shock, ISS score; those related to the lesion: mechanism, above or below the knee, bone lesions, venous lesions and skin decay. A univariate and multivariate analysis were performed to determine the risk factor(s) independently associated with the occurrence of amputation.

RESULTS

57 IIVI were found in 54 patients. The mean ISS was 32,3 ± 21. A primary amputation was performed in 19%, and secondary in 14% of cases. Overall amputation rate was 35% (n=19). Multivariate analysis reveals that the ISS is the only predictor of primary (p=0.009; OR:1.07; CI:1.01-1.12) and global (p=0.04; OR:1.07; IC:1.02-1.13) amputation. A threshold value of 41 was selected as a primary amputation risk factor with a negative predictive value of 97%.

CONCLUSIONS

The ISS is a good predictor of the risk of amputation in IIVI. A threshold of 41 is an objective criterion helping to decide for a first-line amputation. Advanced age and hemodynamic instability should not be important in the decision tree.

American Association for the Surgery of Trauma-World Society of Emergency Surgery guidelines on diagnosis and management of peripheral vascular injuries

The peripheral arteries and veins of the extremities are among the most commonly injured vessels in both civilian and military vascular trauma. Blunt causes are more frequent than penetrating except during military conflicts and in certain geographic areas. Physical examination and simple bedside investigations of pulse pressures are key in early identification of these injuries. In stable patients with equivocal physical examinations, computed tomography angiograms have become the mainstay of screening and diagnosis. Immediate open surgical repair remains the first-line therapy in most patients. However, advances in endovascular therapies and more widespread availability of this technology have resulted in an increase in the range of injuries and frequency of utilization of minimally invasive treatments for vascular injuries in stable patients. Prevention of and early detection and treatment of compartment syndrome remain essential in the recovery of patients with significant peripheral vascular injuries. The decision to perform amputation in patients with mangled extremities remains difficult with few clear indicators. The American Association for the Surgery of Trauma in conjunction with the World Society of Emergency Surgery seeks to summarize the literature to date and provide guidelines on the presentation, diagnosis, and treatment of peripheral vascular injuries. LEVEL OF EVIDENCE: Review study, level IV.

Popliteal artery injuries. Less ischemic time may lead to improved outcomes

BACKGROUND

Popliteal artery injuries are rare. They have high amputation rates.

OBJECTIVES

To report our experience, identify predictors of outcome; mechanism of injury (MOI), Mangled Extremity Severity Score (MESS) score and length of ischemic time. We hypothesized that ischemic time as close to six hours results in improved outcomes.

METHODS

Retrospective 132-month study. All popliteal artery injuries. Urban Level I Trauma Center.

OUTCOME MEASURES

MOI, ISS, MESS, ischemic time, risk factors for amputation, role of popliteal venous injuries, and limb salvage.

STATISTICAL ANALYSIS

univariate and multivariate.

RESULTS

76 patients - 59 (76.1%) males and 17 (22.4%) females. MOI: penetrating - 54 (71%). MESS for penetrating injuries - 5.8 ± 1.5, blunt injuries - 5.6 ± 1.8. Admission-perfusion restoration (n = 76) - 5.97 hours (358 minutes). Ischemic time was not predictive of outcome (p = 0.79). Ischemic time penetrating (n = 58) 5.9 hours (354 ± 209 minutes), blunt 6.1 hours (371 ± 201 minutes). Popliteal arterial repairs: RSVG 44 (58%), primary repair 21 (26%), PTFE 3 (4%), vein patch 2 (2%), ligation 2 (3%), exsanguinated 4 (6%). No patients underwent stenting. Popliteal Vein: Repair 19 (65%), ligation 10 (35%). Fasciotomies 45 patients (59%).

OUTCOMES

Limb salvage - 90% (68/76). Adjusted limb salvage excluding intraoperative deaths - 94% (68/72). Selected patient characteristics; MOI: penetrating vs. blunt - age (p <0.0005). Amputated vs. non-amputated patients, age (p < 0.05). ISS (p < 0.005) predicted amputation, MESS (p = 0.98) did not. Mean ischemic time (p = 0.79) did not predict amputation. Relative risk of amputation, MOI - blunt (p = 0.26, RR 4.67, 95% CI: 1.11 - 14.1), popliteal artery ligation (p = 0.06, RR 3.965, 95% CI: 1.11 - 14.1) as predictors of outcome. Combined artery and vein injuries (p = 0.25) did not predict amputation.

CONCLUSIONS

Decreasing ischemic time from arrival to restoration of perfusion may lead to improved outcomes and increased limb salvage. MESS is not predictive for amputation. Blunt MOI is a risk factor for amputation. Maintaining ischemic times as close to six hours as possible may lead to improved outcomes.

Meta-analysis of prognostic factors for amputation following surgical repair of lower extremity vascular trauma

Background

Lower extremity vascular trauma (LEVT) is a major cause of amputation. A clear understanding of prognostic factors for amputation is important to inform surgical decision-making, patient counselling and risk stratification. The aim was to develop an understanding of prognostic factors for amputation following surgical repair of LEVT.

Methods

A systematic review was conducted to identify potential prognostic factors. Bayesian meta-analysis was used to calculate an absolute (pooled proportion) and relative (pooled odds ratio, OR) measure of the amputation risk for each factor.

Results

Forty-five studies, totalling 3187 discrete LEVT repairs, were included. The overall amputation rate was 10·0 (95 per cent credible interval 7·4 to 13·1) per cent. Significant prognostic factors for secondary amputation included: associated major soft tissue injury (26 versus 8 per cent for no soft tissue injury; OR 5·80), compartment syndrome (28 versus 6 per cent; OR 5·11), multiple arterial injuries (18 versus 9 per cent; OR 4·85), duration of ischaemia exceeding 6 h (24 versus 5 per cent; OR 4·40), associated fracture (14 versus 2 per cent; OR 4·30), mechanism of injury (blast 19 per cent, blunt 16 per cent, penetrating 5 per cent), anatomical site of injury (iliac 18 per cent, popliteal 14 per cent, tibial 10 per cent, femoral 4 per cent), age over 55 years (16 versus 9 per cent; OR 3·03) and sex (men 7 per cent versus women 8 per cent; OR 0·64). Shock and nerve or venous injuries were not significant prognostic factors for secondary amputation.

Conclusion

A significant proportion of patients who undergo lower extremity vascular trauma repair will require secondary amputation. This meta-analysis describes significant prognostic factors needed to inform surgical judgement, risk assessment and patient counselling.

Penetrating arterial trauma to the limbs: outcome of a modified protocol

Background

Penetrating arterial injuries to the limbs are common injuries in high volume trauma centers. Their overall surgical results reported in the literature are satisfactory - apart of those of the popliteal artery that still may lead to a significant incidence in amputations. With the present study we assessed our outcome with penetrating arterial injuries to the limb as to see if the direct involvement of vascular surgeons in the management of popliteal artery injuries leads to an improved (lowered) amputation rate. Results were benchmarked with our published results from previous years.

Methods

All patients sustaining penetrating arterial injuries to the limbs admitted to the Chris Hani Baragwanath Academic Hospital during an 18- month period ending in September 2011 were included in this study. Axillary, brachial and femoral artery injuries were operated on by the trauma surgeons as in the past. All popliteal artery injuries were operated on by the vascular surgeons (new).

Results

There were a total of 113 patients with 116 injuries, as some patients had multiple vascular injuries: 10 axillary, 47 brachial, 34 femoral and 25 popliteal artery injuries. Outcome of axillary, brachial and femoral artery injury repair were excellent and not significantly different from our previous reported experience. Injury to the popliteal artery showed a diminished re-exploration rate from 34% down to 10% (p = 0,049) and a decrease of amputation rate from 16% to 11% which was statistically not significant (p = 0,8).

Conclusion

Penetrating arterial trauma to the axillary, brachial and femoral artery is followed by excellent results when operated by trauma surgeons. In the case of popliteal artery injury operated by the vascular surgeons, the results of this study do not show any statistically significant difference related to amputation rate from our previous reported studies when operated by trauma surgeons. Taking into consideration the diminished re-exploration rate and a tendency to a lower amputation rate, we feel that there is possible tendency of better outcome if operated by vascular surgeons. Multicenter studies with large number of enrolled patients will be required to prove the validity of this suggestion.