Predictors for the immediate and long-term outcome of a vascular surgical procedure.

BACKGROUND AND AIMS: The ability to predict post-operative mortality reliably will be of assistance in making decisions concerning the treatment of an individual patient. The aim of this study was to test the GAS score as a predictor of post-operative mortality in vascular surgical patients. MATERIAL AND METHODS: A total of 157 consecutive patients who underwent an elective vascular surgical procedure were included in the study. The Cox proportional hazards model was used in analyzing the importance of various preoperative risk factors for the postoperative outcome. ASA and GAS were tested in predicting the short and longterm outcome. On the basis of the GAS cut-off value 77, patients were selected into low-risk (GAS low: GAS<77) and high-risk (GAS high: GAS>or=77) groups, and the examined risk factors were analyzed to determine which of them had predictive value for the prognosis. RESULTS: None of the patients in the GAS low group died, and mortality in the GAS high group was 4.8% (p=0.03) at 30 days follow-up. The 12-month survival rates were 98.6% and 78.6% (p=0.0001), respectively, with the respective 5-year survival rates of 76.7% and 44.0% (p=0.0001). The only independent risk factor for 30-day mortality was the renal risk factor (OR 20.2). The combination of all three GAS variables (chronic renal failure, cardiac disease and cerebrovascular disease), excluding age, was associated with a 100% two-year mortality. CONCLUSIONS: Mortality is low for patients with GAS<77. For the high-risk patients (GAS>or=77), due to its low predictive value for death, GAS yields limited value in clinical practice. In cases of patients with all three risk factors (renal, cardiac and cerebrovascular), vascular surgery should be considered very carefully.

Impact of endovascular treatment on clinical status and health-related quality of life.

BACKGROUND AND AIMS: Investigating the impact of percutaneous transluminal angioplasty (PTA) on clinical status and health related quality of life in patients with claudication and critical limb ischaemia (CLI). MATERIAL AND METHODS: 61 patients and 64 limbs underwent a primary PTA (30 claudication and 34 CLI cases). Clinical status was graded according to Ahn and Rutherford and ankle/brachial index (ABI). Quality of life was assessed using the Nottingham Health Profile (NHP) preoperatively, one month and one year after the procedure. Triplex scan evaluation of the treated arterial segment was carried out postoperatively and one year after the procedure. RESULTS: Claudication: 24/27 patients underwent one-year follow up, after which 20/24 had no claudication. In triplex evaluation 17 (63.0%) treated segments were open with 0-50% restenosis, 9 (33.3%) with 51-99% restenosis and one (3.7%) was occluded. CLI: 13/34 (38.2%) patients underwent one-year follow-up after which eight patients (61.5%) were asymptomatic and five (38.1%) had claudication. In triplex evaluation there was 0-50% restenosis in 6 (46.2%) segments treated with PTA and 51-99% restenosis in 7 (53.8%) segments. 21 (61.8%) patients did not conclude the one year follow up: 7 had died, 5 had undergone bypass surgery and 6 an amputation and 3 did not attend the follow-up up for unknown reasons. Quality of life: For CLI patients, improvement was observed in the domain of pain, which continued throughout the follow-up period. Among the claudicants, the domain of physical mobility was improved at one month's follow-up, but this effect disappeared during the following year and could not be seen at one the one- year follow-up. CONCLUSIONS: Technical success and one-year results in claudication are good, and the rate of complications is low. However, although PTA resulted in an immediate improvement in the quality of life, this effect was not seen in the long term. In critical limb ischemia there was a group of patients in whom PTA led to a significant benefit in terms of limb salvage and quality of life.

Lower limb amputations: differences between the genders and long-term survival.

The purpose of the study was to evaluate possible differences between genders in amputation incidence, revascularization activity before and survival after amputation. This population-based study was carried out in a well-defined geographical area, where all vascular surgical consultations and reconstructions are performed in one university hospital. All amputations performed in the region during 1990 - 1999 were identified from the hospital central registers. According to patient's identity codes, the Cause of Death Registry of Statistics Finland provided death data. Amputation data were cross-linked with the local vascular registry using identity codes. Women were found to be 8 years older than men (p < 0.0001). Major amputations comprised 73.4% in males and 77.7% in females. The age-standardized amputation incidence among males was 338 and among females 226 (per 10(6) inhabitants/year) (p < 0.001). The most prominent difference was seen in amputations due to trauma, where the age-adjusted major amputation incidence was over three-fold among males compared to females. The proportion of patients who had undergone vascular procedure before amputation was 23% in both genders. Median survival after amputation was 943 days in men and 716 in women (p = 0.01). When the higher age of women was considered, there was no significant difference between the genders. Survival was poorer among diabetics in both genders and the difference was significant in males. The amputation incidence was found to be higher in men compared to women in all etiologic subgroups except malignant tumour. Almost one in 4 patients had undergone vascular surgical reconstruction before amputation in both genders. There was no significant difference between the genders in survival after amputation. Subjects with diabetes had a poorer survival after major amputation than those without diabetes.

Preoperative physical examination for primary vascular access--reliability in determining vessel quality.

BACKGROUND AND AIMS: The purpose of this prospective clinical study was to evaluate the reliability and adequacy of preoperative physical examination in determining the quality of vessels prior to primary vascular access procedure by performing peroperative completion fistulography. MATERIAL AND METHODS: 26 consecutive patients who were scheduled for primary vascular access surgery, between July 2001 and June 2002, were included. Findings between the preoperative physical examination and peroperative completion fistulography were compared. RESULTS: Of the 26 patients that were initially enrolled in the study, 4 patients were excluded because physical examination showed poor superficial arm veins and 2 patients had not undergone access procedure by the end of the study. The remaining twenty patients constituted the actual study group. The arteriovenous fistula could be performed at the chosen level and way in all 20 patients. The findings between preoperative physical examination and peroperative fistulography were compatible and the specificity of physical examination to detect patent inflow and outflow vessels was 100%. Due to the fact that 4 patients in whom a poor vein was suspected were excluded, the sensitivity could not be assessed. CONCLUSIONS: Preoperative physical examination seems to be reliable and adequate method in determining vessel quality prior primary vascular access surgery. According to our study, its specificity is high in determining patent inflow and out-flow vessels. However, because of exclusion of patients with suspected problem, sensitivity cannot be determined.

Serum retinol, 25-hydroxyvitamin D and alpha-tocopherol of racing trotters in Finland.

Serum levels of retinol, 25-hydroxyvitamin D2, 25-hydroxyvitamin D3 and alpha-tocopherol were determined by high performance liquid chromatography from 142 Standardbred and Finnish Coldblooded Trotters aged three to 15 years. Blood samples were collected during January and July. Serum levels of retinol and alpha-tocopherol were about a third of those in man, with summer values indicating an increase in most horses. The relatively low serum concentrations of 25-hydroxyvitamin D and alpha-tocopherol suggest that during the winter season a deficiency of these vitamins may occur in horses in northern countries such as Finland. Significant differences were observed between values of horses from different stables, especially for serum alpha-tocopherol. The differences probably reflect differences in the quality of feeds and/or different feeding practices.

Practical identifiability of growth and substrate consumption models.

The estimation of parameters in several dynamic models, which describe growth and substrate consumption, has been carried out using a modified Gauss-Newton-type method. The four models considered are Monod, Contois, linear specific growth rate, and an enzyme kinetic model. The initial values of the differential equations are included in the parameter vector which will be estimated. The efficiency of the method and the confidence limits of the parameters were studied using simulated measurement noise. The experimental results describe Trichoderma viride growing on glucose as the main carbon source.