Patency of autologous and prosthetic arteriovenous fistulas in elderly patients.

OBJECTIVE: To compare the patency of autologous and graft-bridging (prosthetic) arteriovenous (AV) fistulas in patients 70 years of age or more. DESIGN: Non-randomised comparative study. SETTING: University hospital, Greece. PATIENTS: 114 patients aged 70 years or more (mean 78) who required 135 consecutive angioaccess procedures during the 8-year period January 1990-December 1997. INTERVENTIONS: 68 autologous and 67 prosthetic procedures, 64 of the prosthetic procedures being proximal brachioaxillary AV arm grafts. MAIN OUTCOME MEASURES: Primary and secondary cumulative patency rates and cumulative survival. RESULTS: Life table analysis showed that the 3-year secondary patency (medium term patency) was significantly superior in the prosthetic group (58% compared with 44%, p = 0.04). Cumulative survival at 3-years was 21%. CONCLUSIONS: A proximal brachioaxillary prosthetic AV graft is a good alternative as initial primary access in elderly patients who are not suitable for an autologous proximal AV fistula. At this age long term patency and conservation of proximal access sites are of minimum importance because of their limited life expectancy.

Indications for surgical treatment of angioaccess-induced arterial "steal".

BACKGROUND: Arterial "steal" is a well-known complication following proximal arteriovenous (AV) fistula, but its manifestations comprise a wide spectrum of symptoms and there are no clear indications for those patients who need surgical repair. STUDY DESIGN: Among 180 consecutive AV fistulas of various configurations, with the brachial artery as the donor artery in all patients, 111 patients were studied retrospectively (group A) and 69 patients were studied prospectively (group B). Patient records were reviewed in group A, and the decision for surgical correction of limb-threatening steal was based on clinical grounds only. In group B, all patients were followed prospectively; postoperative systolic blood pressure measurements were obtained, and a systolic pressure index (SPI) was calculated (postoperative forearm systolic pressure divided by contralateral forearm systolic pressure). In patients with an SPI < 0.6, nerve conduction studies (NCS) were performed. The decision for operation in this group was based on clinical examination, SPI, and NCS. RESULTS: Seven patients were operated on for steal-induced limb-threatening ischemia; in all seven patients, ischemia developed immediately after access construction. One additional patient with mild symptoms and deterioration in repeated NCS was considered a candidate for ischemic monomelic neuropathy and was successfully operated on 1 month later. The ligation-bypass technique was used in all patients, consisting of arterial ligature distal to the takeoff of the graft and short arterial bypass from a point proximal to the inflow of the access to a point just distal to ligation. In 94% of the patients, some degree of distal ischemia was detected (SPI < 0.8); patients with SPI < 0.5 were most likely to have impaired NCS. CONCLUSIONS: Steal-induced limb-threatening ischemia necessitating immediate surgical repair occurred in 3.9% (7 of 180) of our patients. The decision for surgical correction of steal should be based on clinical examination. Nerve conduction studies may be useful in patients who have an SPI value < 0.5 to detect candidates who might develop ischemic monomelic neuropathy. In similar patients, surgical treatment of steal should be offered.

Incidence and patterns of iatrogenic arterial injuries. A decade's experience.

OBJECTIVE: To investigate the incidence and patterns of all iatrogenic arterial injuries (IAI) necessitating surgical repair in a ten-year period. DESIGN: Retrospective study. SETTING: Departments of Vascular Surgery a) Athens General Hospital "G. Gennimatas" and b) Red Cross Hospital of Athens, Greece. PATIENTS: Eighty-seven patients underwent surgical repair of an IAI, comprising 36% of the 237 patients treated surgically for various arterial injuries during the same period. RESULTS: Specific injury patterns were implicated in most cases. Cardiac catheterizations were the commonest cause of IAI (n=39). The second commonest source for IAI was the renal units' personnel accountable for 17 false aneurysms, which arose at arteriovenous grafts' puncture sites. Among the surgical specialties orthopaedic surgery was the most common source of IAI (n=13). A less common pattern of IAI was following radical operations for cancer (n=7). The mortality of the series was 4.6% (4/87) and the amputation rate 2.3% (2/87). No death or amputation was associated with IAI following cardiac catheterizations confirming that post-catheterization IAI have a benign prognosis. False aneurysm was the most frequent complication when the cardiac catheterization was via the femoral artery, when the catheterization was via the brachial artery the commonest complication was arterial thrombosis. The two amputations were due to delayed reconstruction of arterial injuries that were not recognised at first sight. CONCLUSION: Common patterns characterize most IAI. Understanding their exact causes is a first step towards prevention or timely repair if the latter is not feasible.

POSSUM and APACHE II scores do not predict the outcome of ruptured infrarenal aortic aneurysms.

Forty consecutive patients were admitted alive to the operating theater with ruptured infrarenal aoritc aneurysms in a 3-year period and were assessed preoperatively with two scoring systems: the POSSUM (physiological and operative severity score for the enumeration of mortality) and the APACHE II (acute physiologic and chronic health evaluation). The aim of the study was to investigate the capacity of the two scores to predict the patients' outcome. The operative mortality of the series was 55% (22/40). The average POSSUM score was 63.3 for survivors and 66.5 for the nonsurvivors (difference not statistically significant). APACHE II score averaged 11.3 in survivors and 14.5 in nonsurvivors (p = 0.02). APACHE II score 17 was the threshold value with the highest combined specificity and sensitivity; however, at this point the positive predictive value for a death was 92% and the negative predictive value was 63%. Interestingly, the only single factor in univariate analysis affecting mortality was the preoperative platelet count and is not taken into account in neither of the two scoring systems. POSSUM failed in predicting the outcome of ruptured infrarenal aortic aneurysms. APACHE II was a good predictor of outcome; however, its power to predict the outcome in any given individual patient was limited. As precise prediction is impossible, repair in every patient should not be denied.

Factors affecting the lifespan of autologous and synthetic arteriovenous access routes for haemodialysis.

OBJECTIVE: To try and establish a consensus about the ideal secondary access for haemodialysis by assessing factors that affect the longevity of various access routes. DESIGN: Multicentre survey, by questionnaire. SETTING: General hospital, Athens. SUBJECTS: All 1516 patients in the Athens area receiving chronic haemodialysis. MAIN OUTCOME MEASURES: Longevity of present and any previous access routes (n = 2323). Data including type of access, age, sex and the existence of diabetes, hypertension, hyperlipidaemia, or other systematic diseases were recorded. RESULTS: Some 1220 (80%) of the patients were using autologous access, 1049 (69%) arteriovenous (AV) fistulas at wrist and 171 (11%) at elbow. Variables were analysed using Cox's proportional hazard model. Age and female sex were significantly associated with failure of autogenous access (p < 0.001) although not affecting synthetic grafts. Autogenous fistula at the elbow was the only secondary access that was less likely to fail than the initial (baseline) fistula at the wrist. Among the various grafts, straight arm grafts had the best prognosis and straight forearm grafts were the most likely to fail (p < 0.001). CONCLUSION: An AV fistula at the elbow should be considered the second best after the fistula at wrist, but is not always feasible. A synthetic graft is more likely to be needed in elderly patients and women, in whom an autogenous AV fistula is more likely to fail.

Popliteal artery and trifurcation injuries: is it possible to predict the outcome?

The records of 18 consecutive patients with popliteal and/or trifurcation civilian arterial injuries, who underwent revascularisation procedures during a 5-year period, were retrospectively assessed. All patients were classified using four, previously described, severity scoring systems in an effort to investigate the accuracy of predicting the outcome of this type of injury. Classification of the severity of popliteal artery trauma would be useful (a) for setting objective criteria (if any) for primary amputation and (b) for retrospective assessment of the results in vascular audit. The amputation rate in this group was 28%. Limbs which could not be salvaged were all in the "trifurcation" group and in this subset of patients the amputation rate was 71% (5/7). The scoring index having the higher overall accuracy (94%) was the mangled extremity syndrome index (MESI) with a predictive value for amputation of 83%. The use of these indices as criteria for primary amputation needs further evaluation as no scoring system was specific enough to permit primary amputation on that basis alone. The predictive value for limb salvage was 100%, for all four scoring systems enabling their use in vascular trauma audit.

Severe facial ischaemia caused by ergotism.

A case of ergotamine induced severe face ischaemia mimicking acute arteritis is presented. The unique clinical picture was due to bilateral involvement of both external carotid arteries. No case of ergotism with such a localization has been previously described in the literature.

Iatrogenic arterial trauma associated with hip joint surgery: an overview.

Four cases of iatrogenic arterial injuries following hip surgery are reported. An overview of the literature revealed 122 additional cases. In 93 (74%) of these cases the arterial damage occurred following total hip replacement, 27 (21%) were related to hip fracture correction and six cases complicated other hip surgery procedures. Revisional hip surgery was found to be a definite risk factor. Injuries associated with hip replacement differ significantly in various characteristics of those associated with hip fracture correction. There was a 9% mortality and a 17% permanent disability rate in patients with arterial trauma following total hip replacement. In this group a significantly higher permanent disability rate was noticed in patients who first presented with ischaemia (p less than 0.05). No relationship between the location and mechanism of injury and the outcome was found. Mortality and permanent disability rates of 4% and 11%, respectively, were noticed in patients with injuries related to hip fracture correction.

Iatrogenic and noniatrogenic arterial trauma: a comparative study.

During a 6-year period 22 patients were operated on because of iatrogenic arterial trauma (group A) and 43 sustained noniatrogenic arterial injury (group B). The group A injuries were caused by various arterial catheterization procedures for angiography or cardiac investigation (55%) or surgical interventions (45%). Haemorrhage was more common in group B than in group A (p less than 0.001). The mortality rate did not differ significantly between the groups (14% vs. 9%). Permanent disability was more common in group B (p less than 0.05), due mainly to higher incidence of associated venous, neural, skeletal or visceral injuries. Bypass operations tended to be more often performed in group B than in group A, but the difference was not statistically significant. Retrospective assessment of the appropriateness of technique, made separately by two vascular surgeons, revealed instances of potentially avoidable iatrogenic arterial injury. The rising incidence of iatrogenic arterial trauma may therefore be considered 'reducible'.