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1.
The purpose of this study was to compare the physiological responses of professional and elite road cyclists during an incremental cycle ergometer test. Twenty-five elite cyclists (EC; 23+/-1 yr) and 25 professional cyclists (PC; 25+/-2yr) performed a ramp protocol (increases of 25 W x min(-1)) during which the following parameters were measured: oxygen consumption (VO2), pulmonary ventilation (VE), ventilatory equivalents for oxygen and carbon dioxide (VE x VO2(-1) and VE x VCO2(-1), respectively), respiratory exchange ratio (RER), ventilatory thresholds 1 and 2 (VT1 and VT2, respectively), blood lactate, and electromyographic activity (EMG) of the vastus lateralis. Significant differences existed between the two groups mainly at submaximal intensities, since both VT1 and VT2 occurred at a higher exercise intensity (p<0.001) in PC than in EC (VT2: 80.4+/-6.6 vs 87.0+/- 5.9% VO2max in EC and PC, respectively). Lactate levels showed a similar response in both groups at low-to-moderate intensities (< 300 W), and thereafter blood lactate was significantly higher in EC. Finally, the "electromyographic threshold" (EMGT) occurred at a significantly higher intensity (p < 0.05) in PC when compared to EC (64.7+/-14.2 vs 56.0+/-14.9% VO2max, respectively). It was concluded that, in comparison with EC, PC exhibit some remarkable physiological characteristics such as a high VT2, an important reliance on fat metabolism even at high power outputs, and several neuromuscular adaptations.  相似文献   

2.
OBJECTIVES: To determine if cell-salvaged autologous blood can serve as an alternative to homologous blood, and to examine the incidence of infected complications and length of postoperative stay. DESIGN: A prospective randomised study comprising autologous and homologous blood transfusions in patients undergoing elective infrarenal abdominal aortic surgery. METHODS: Fifty patients undergoing AAA surgery were prospectively randomised to homologous blood (n = 27), or autologous blood transfusion (n = 23), using a cell salvage autotransfusion device. RESULTS: The haemoglobin at the time of hospital discharge was similar for both groups (11.0 vs. 10.8 g/dl) with no difference in perioperative mortality. The length of stay was reduced in those patients who received autologous blood (9 days vs. 12 days, p < 0.05 Mann-Whitney U test). There were four infected cases in the autologous group and 12 in the homologous group (p = n.s., Fisher's exact probability test). However, patients who received 3-4 units of homologous blood had an increased risk of infection compared to those who received a similar amount of autologous blood (50% vs. 0%). CONCLUSIONS: Cell salvage autologous blood can safely replace, or at least decrease, exposure to homologous blood transfusion, with a reduction in the mean hospital stay.  相似文献   

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Preoperative recognitiion of horseshoe or pelvic kidney with abdominal aortic aneurysm greatly facilitates proper operative care of such patients. Operative management of three reported patients varied significantly, depending on complicated and anomalous blood supply to the kidney.  相似文献   

5.
Abdominal aortic aneurysms occur in 5 to 7 percent of people over age 60 in the United States. An aneurysm is defined as a permanent localized dilatation of an artery, with an increase in diameter of greater than 1.5 times its normal diameter. Abdominal aortic aneurysms may be manifested by catastrophic rupture, signs of pressure on other viscera or an embolism originating in the aneurysmal wall, but most cases are asymptomatic. The diagnosis is often made by physical examination of the abdomen, which reveals a pulsatile mass left of the midline, between the xyphoid process and the umbilicus. The diagnosis may be confirmed by B-mode ultrasound. Ultrasound screening should be considered for individuals at risk for abdominal aortic aneurysms. This group includes individuals over age 60 who smoke, have hypertension or have vascular disease. Elective surgical intervention is indicated for most patients with abdominal aortic aneurysms greater than 5 cm in diameter to prevent rupture and death. Smaller abdominal aortic aneurysms should be monitored by regular ultrasound measurements. Screening and identification of abdominal aortic aneurysms by primary care physicians can have a significant impact on patient survival.  相似文献   

6.
INTRODUCTION: Rupture of abdominal aortic aneurysms (RAAA) can take place in one of the 4 following ways: 1. "Open" rupture in the free peritoneal cavity; 2. "Closed" rupture with formation of retroperitoneal haematoma; 3. Rupture into surrounding cavity structures, such as veins and bowels; 4. In rare cases rupture is effectively "sealed of" by the surrounding tissue reaction, and retroperitoneal haematoma is "chronically" contained [1]. The terms "sealed" [2], "spontaneously healed" [3], "leakig" [4] RAAA, were also used in the previous papers connected to this situation. The "sealed" rupture was first described by Szilagyi and associates in 1961 [2]. In their case the rupture was small and haemorrhage was effectively encircled by the tissue surrounding the aortic wall. The slow rate of blood loss contributed to the patient's haemodinamically stable condition. Christenson et al. reported a case of "spontaneously healed" RAAA [3]. Rosenthal and associates described 2 patients who had aortic aneuryms that ruptured several months before repair and contributed to the term "leaking AAA" [4], while Jones et al. introduced the term "chronic contained rupture" [1]. The aim of this paper is the presentation of 5 such patients. CASE REPORT: Between December 1, 1988 and May 30, 1997 411 patients with abdominal aortic aneurysms (AAA) have been operated at our institute. Of this number 137 (33%) had RAAA, while 5 patients (12%) had a contained RAAA (CRAAA). CRAAA were found in 3 male and two female patients, average age 62 years. All of them had a previously proved AAA and initial symptoms lasted for days or months before the admission. In all patients haematocrit, pulse rate and arterial tension during the admission, were normal. All typical signs of RAAA were absent in these patients. Patient 1. A 56-year-old man, smoker, with previous history of arterial hypertension had an isolated episode of abdominal pain and collapse 30 days before the admission. Physical examination revealed a pulsatile abdominal mass. Doppler ultrasonography identified an infrarenal AAA, with right lobular extraaneurysmal mass which displaced the inferior vena cava (ICV). Angiographically (Figure 1a) an unusual saccular intrarenal AAA was detected, while simultaneous cavography (Figure 1b) confirmed the-dislocated inferior vena cava to the right. The intraoperative finding showed infrarenal CRAAA with organized retroperitoneal haematoma between AAA, ICV and duodenum. After aortic cross clamping and aneurysmal opening, the rupture at the right posterior aneurysmal wall was discovered. The partial aneurysmactomy and aortobilliar bypass procedure with bifurcated knitted Dacron graft (16 x 8 mm), were performed. The patient recovered very well. After a 4-year follow-up period the graft is still patent. Patient 2. A 72-year-old woman with low back pain, fever and disuric problems was urgently admitted to the Institute of Urology and Nephrology. The standard urological examination (X-ray, intravenous pyelography, retrograde urography, kidney Duplex ultrasonography) excluded urological diseases. However, intrarenal AAA an a giant aneurysm of the right common iliac artery, were found. The proximal dilatation of the right excretory urinary system was also found by retrograde urography. The patient was transported to our Institute 20 days after the initial symptoms. Translumbar aortography (Figure 3) showed the right common iliac artery aneurysm and gave the false negative picture of normal abdominal aorta because of parietal thrombosis of AAA. The intraoperative finding showed chronic rupture of the posterior wall of the right common artery aneurysm. The retroperitoneal haematoma compressed the right ureter. Both aneurysm have been resected and replaced by bifurcated Dacron graft (16 x 8 mm). The patient recovered successfully. After a 2-year period of follow-up the graft is still patent. Patient 3. (ABSTRACT TRUNCATED)  相似文献   

7.
Percutaneous placement of an endovascular stent, with and without coils, in the treatment of large AAA in animal models is feasible, safe and effective. The covered stent sealed off AAA immediately after stent placement, however, it interrupted blood flow into arteries in the area covered by the stent. The uncovered stent prevented further expansion of the aneurysm and also significantly decreased the incidence of rupture. The long-term patency of branch arteries by the uncovered stent supported the possibility of safely using this approach in humans. Furthermore, either covered stent or uncovered stent with additional coils have the potential for treatment of acute aneurysm rupture or leaking. Most importantly, the aneurysm lumen in our model was gradually replaced by collagen after stent placement which further reduces the risk of aneurysm rupture: and this healing process was enhanced by the addition of coils. If proven safe and effective for humans as well, this technique has the potential for substantially reducing the morbidity and mortality associated with AAA.  相似文献   

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Hyperamylasaemia may occur following abdominal aortic aneurysm rupture and its use as a prognostic indicator has been suggested. However, the isoenzyme responsible for the rise in serum amylase has not been investigated. In this study, isoenzyme analysis was performed on the serum of patients noted to have a raised amylase from their routine biochemistry samples. Individual cases were then reviewed regarding clinical course and outcome. The pancreas has been thought to be the predominant source of the observed hyperamylasaemia. However, in this study a mixed picture of pancreatic and salivary isoenzymes was found. Of the four highest recorded amylase levels two were salivary in origin, one pancreatic and one mixed. The highest recorded amylase level was of salivary origin in a patient that survived without any major complication. The four patients that died all showed evidence of gut infarction/ischaemia. Two had hyperamylasaemia of a mixed pattern, one pancreatic and one of salivary origin.  相似文献   

11.
An increasing number of inflammatory abdominal aortic aneurysms are reported today, although it is not clear whether these are nosologically independent lesions or a particular evolution of atherosclerotic aneurysms with enhanced phlogistic processes and fibrous reaction. Several pathogenetic theories have been proposed (microfissuration, autoimmunity, lymphatic stasis); clinical symptoms are characterised by the frequent involvement of contiguous retroperineal structures (in particular the urinary excretory tract and duodenum) which may be dislocated or compressed by the neoformation. CT or NMR appear to be the instrumental tests which give the most reliable diagnosis regarding the suspected inflammatory nature of the aneurysm. A correct pre-operative diagnosis is particularly important given that the morphological peculiarities (fibrosis and tenacious synechiae) add considerable pitfalls and difficulties to the operation. In this respect, the use of special technical devices, such as minimum dissection, permit a marked reduction of perioperative complications.  相似文献   

12.
PURPOSE: To evaluate the suitability of ultrafast electron-beam tomography (EBT) for the investigation of abdominal aortic aneurysms using CTA. METHODS: Thirty-one patients with suspected abdominal aortic aneurysm were investigated with EBT using an Evolution XP scanner (Siemens, Erlangen) with the newest software version 12.34 with continuous volume scanning of 140 images in 17 s. Collimation was 3 mm, table increment 4 mm with overlapping image reconstruction every 2 mm, exposure time 200 ms (124 mAs), resulting in a scan-range of 28 cm. A quantity of 80 ml contrast material was administered (flow 4 ml/s). Visualization of the abdominal aorta and its branches was performed with MIPs and shaded surface display. Evaluation of image quality was based on a four-step classification scale (1 = good, 4 = insufficient) for the demonstration of the abdominal aorta and the visceral, renal and iliac arteries. RESULTS: All EBT examinations demonstrated high and homogeneous density values along the whole vessel course with a mean density value of 258.7 +/- 47.3 HU for the abdominal aorta and the iliac arteries. Quality evaluation for the vessel demonstration showed mean values between 1.22 and 1.57 for the abdominal aorta and the visceral, renal and iliac arteries. CONCLUSIONS: EBT with 140 slices and slice reconstruction every 2 mm offers a high z-axis resolution resulting in high-quality CT angiographies of the whole abdominal aorta and its branches.  相似文献   

13.
A study of 150 patients examined by ultrasonography is described. It was designed specifically to diagnose and investigate abdominal aortic aneurysms. Sixty-four aneurysms were found. Ultrasonography was useful in distinguishing aneurysms from other conditions and there was a high degree of correlation between size measured by scanning and operative size. In addition to the demonstration of rupture it was possible to perform serial measurements. The technique is simple and quick and causes minimal disturbance to the patient.  相似文献   

14.
The surgical management of regional nodes in patients with cancer has been controversial for many years. This paper reviews the role of elective lymph node dissection in the management of malignant melanoma. The evidence for and against elective lymphadenectomy is discussed and a policy of therapeutic, rather than elective, lymph node excision recommended.  相似文献   

15.
This paper analyzes results of 5-year surgical treatment of patients with ruptured abdominal aorta aneurysms (1991.-1995.) at the Clinic for Vascular and Transplantation Surgery of the Institute of Surgery in Novi Sad. 105 patients with abdominal aorta aneurysm underwent surgery, whereas in 31 patients there was a suspicion of rupture and it was confirmed by US and CT examination. One of basic factors to decrease mortality in these patients is early diagnosis and surgery before hemorrhagic shock occurs. Results in hemodynamic stabile patients with blood pressure over 100 mmHg and regular diuresis are much better with mortality of 20%. In order to estimate the correlation of hemodynamic state and outcome of the operation, patients were divided into three groups--hemodynamic stable with blood pressure over 100 mmHg and regular diuresis at admission: hemodynamic unstable patients with signs of mild or moderate shock and blood pressure under 100 mmHg and without initial diuresis which was regulated at the beginning of therapy and hemodynamic unstable patients in severe shock and unmeasurable blood pressure. The highest survival rate (10% mortality) and the least complications occurred in the first group of patients. The total mortality of patients after surgery was 48.48%. Timely diagnosis, suspicion of rupture and adequate first and with urgent transfer to a competent surgical institution are key factors in treatment of this disease and its outcome.  相似文献   

16.
BACKGROUND: Aortic aneurysm anatomy is crucial when considering patients for endovascular repair. The aim of this study was to determine the proportion of patients with aortic aneurysm suitable for endovascular repair with three different graft-stent systems. METHODS: Spiral computed tomographic angiography was used to assess the anatomy of 154 abdominal aortic aneurysms. Measurements were made of aneurysm neck length and diameter, renal artery to aortic bifurcation length, common iliac artery diameter and length, and external iliac artery diameter. Aneurysms were assessed for anatomical suitability for currently available aortoaortic, aortobi-iliac and aortouni-iliac devices. RESULTS: Six patients (4 per cent) had a distal aortic neck suitable for implantation of a straight aortic graft. Fifteen patients (10 per cent) had arterial anatomy suitable for implantation of a bifurcated graft and 85 (55 per cent) patients were suitable for endovascular repair with an aortouni-iliac graft. The primary reasons for unsuitability were: proximal neck length less than 1.5 cm (44 patients), proximal neck diameter greater than 3.0 cm (12), and angulation of the proximal neck (three). A further ten patients were considered unsuitable for an aortouni-iliac graft because of bilateral common iliac artery aneurysms (four), tortuous iliac arteries (four) and narrow external iliac arteries (two). CONCLUSION: The aortouni-iliac device has the widest applicability of the currently available endovascular systems but open repair remains the only option for a large proportion of patients.  相似文献   

17.
We retrospectively compared patients with NF1 with and without optic pathway gliomas (OPG) to determine the incidence and range of orbital developmental abnormalities and compared the incidence of OPG in African-Americans and whites. From cranial MR scans, we manually measured 14 orbital dimensions, compared them to published standards of Waitzman et al, calculated orbital volumes, and determined the presence or absence of volumetric symmetry (delta v) (delta v < or = 3 cm3 was considered to be symmetrical). We compared the results of orbital configurational assessment between patients with (group I) and those without OPG (group II). The study population comprised 58 patients, 24 boys, 18 African-American, and one Hispanic. Median age at imaging was 7 years (range 0.5-25.5 years). Fifty-eight percent had conformational abnormalities, 16 of whom had more than one abnormality (28%), the most frequent being increased intertemporal distance (n=10), increased lateral orbital distance (n=8), increased medial wall length (n=6), and decreased medial wall length (n=6). The increased intertemporal and lateral orbital distances may contribute to the appearance of hypertelorism. Only two patients had sphenoid wing hypoplasia. We found a high incidence of orbital dimensional abnormalities in the total population but more often saw multiple abnormalities in patients with OPG. However, no pattern of configurational abnormality emerged. OPG is less frequent in African-Americans. Orbital volumetric disparity seems to be independent of the presence of OPG.  相似文献   

18.
We experienced 8 cases who required reoperations, including 2 re-redo operations, after repairs of infrarenal abdominal aortic aneurysms. Of 8 patients, one patient developed a new aneurysm due to atherosclerosis in thoraco-abdominal aorta involving all visceral arteries and other 7 patients had aneurysmal formations at proximal anastomotic sites, including 3 suprarenal, 2 juxtarenal and 2 infrarenal aortic lesions. Etiology at initial operation in patients who subsequently developed anastomotic aneurysms included vasculo-Beh?et disease in 4, atherosclerosis in 2 and dissecting aortic aneurysms type III due to Marfan syndrome in 1. At reoperation, all who had vasculo-Beh?et disease had ruptures of anastomotic sites and 2 patients underwent repairs of dehiscent patch, 1 extra-anatomic bypass between ascending and abdominal aorta and 1 interposition of graft. One patient who had graft infection after repair of abdominal aortic aneurysm required axillo-femoral bypass with removal of infected graft. A patient who had dehiscence of proximal anastomosis after repair of aortoiliac occlusive disease required interposition of graft. Two patients, Marfan syndrome and aneurysm in thoraco-abdominal aorta, underwent graft replacement of thoraco-abdominal aorta concomitant with reconstruction of all visceral arteries. There were 8 patients who required reoperations for aneurysms at distal anastomotic sites after repairs of abdominal aortic aneurysms. Five patients underwent repairs of new aneurysms, including replacement of total arch in 3, descending aorta in 1 and iliac artery in 1. In all cases, no hospital death was noted, however, late deaths were occurred in vasculo-Beh?et disease, Marfan syndrome and graft infection. Thus, late result depends on etiology of disease. Although patients who requires reoperation after repair of abdominal aortic aneurysms have higher operative risk factors, early and late results are satisfactory compared to initial operations.  相似文献   

19.
A prototype simulator for training in endovascular repair of abdominal aortic aneurysms (AAA) has been developed. Employing transparent models of human AAA complete with renal, iliac and femoral arteries, this system allows accurate simulation of aortography, road-mapping, catheter guidewire manipulation and stent-graft deployment while obviating the need for ionising radiation.  相似文献   

20.
The stability of cisatracurium besylate was studied. Cisatracurium (as besylate) 2 mg/mL in 5- and 10-mL unopened vials and 10 mg/mL in 20-mL unopened vials, as well as 3 mL of solution from additional 2-mg/mL vials, repackaged in 3-mL sealed plastic syringes, was stored at 4 and 23 degrees C in the dark and in normal fluorescent room light. Admixtures of cisatracurium (as besylate) 0.1, 2, or 5 mg/mL in polyvinyl chloride (PVC) minibags of 5% dextrose injection or 0.9% sodium chloride injection were stored at 4 and 23 degrees C in normal fluorescent room light. Triplicate samples for each storage condition were taken initially and at 1, 3, 5, 7, 14, 21, and 30 days; samples from vials were also removed at 45 and 90 days. Solutions were stored in sterile vials at -70 degrees C and then thawed at room temperature before analysis of chemical stability by high-performance liquid chromatography. Physical stability was assessed as well. Cisatracurium besylate was physically stable in all samples throughout the study. Cisatracurium (as besylate) 2 mg/mL exhibited drug losses at 23 degrees C in vials at 45 days and in syringes at 30 days. Cisatracurium (as besylate) 0.1, 2, and 5 mg/mL in 5% dextrose injection and in 0.9% sodium chloride injection was stable for at least 30 days at 4 degrees C, but substantial drug losses occurred at 23 degrees C. Admixtures prepared with cisatracurium (as besylate) 0.1 mg/mL and with 5% dextrose injection exhibited the greatest losses. Cisatracurium besylate was stable in most samples for at least 30 days at 4 and 23 degrees C; admixtures containing cisatracurium (as besylate) 0.1 or 2 mg/mL exhibited substantial drug loss at 23 degrees C.  相似文献   

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