The use of omental flaps in abdominal aortic surgery: a review and description of a simple technique.
Explore the source record for details and available documents.
Aorta, Abdominal↗
Biomedical subjects
J D Corson
Publications and source records attributed to J D Corson.
A comparative evaluation of femorofemoral crossover bypass and iliofemoral bypass for unilateral iliac artery occlusive disease.
The purpose of this study was to compare the results of extra-anatomic femorofemoral crossover bypass grafting to the anatomic iliofemoral bypass grafting procedure in the treatment of patients with unilateral iliac artery occlusive disease with respect to patency and limb salvage. The records of all patients with unilateral iliac artery disease who underwent revascularization between January 1988 and December 1995 at the University of Iowa Hospitals and Clinics (UIHC) were retrospectively reviewed; 108 patients were identified and divided into two groups. Group I (n=68; male/female=44/24) was composed of all patients who underwent a femorofemoral crossover extra-anatomic bypass. All patients who underwent an iliofemoral anatomic bypass constituted group II (n=40; male/female=24/16). The mean age for group I was 60 years (range 28-87) and for group II, 54 years (range 14-86). The medical risk factors between both groups were comparable. Except for the higher incidence of gangrene in group II the indications for surgery were comparable between both groups. A polytetrafluoroethylene graft was used in 88% of group I patients and in 90% of group II patients (NS). In the remaining patients, an autogenous vein conduit was used. Two patients from group I (2.9%) died in the perioperative period (NS). Graft patency was assessed by clinical evaluation, Doppler-derived ankle/brachial indices, and color duplex imaging. The cumulative primary and secondary patency rates, limb salvage, and patient survival were calculated by use of life table analysis (SE<0.1). The need for simultaneous outflow and inflow procedures at the time of surgery was comparable between both groups. The proportion of patients who underwent further revascularization during follow-up was also comparable. The 5-year primary and secondary graft patency rates were 81.7% and 90.3%, in group I and 61.3% and 80.5% in group II. Although the difference between both groups was not significant there was a tendency toward higher rates with femorofemoral bypass. The 5-year survival rates of 80.3% for group I and 73.3% for group II were comparable. These data suggest that there is no significant difference in the long-term results between the femorofemoral crossover bypass grafts and iliofemoral grafts. Both procedures result in acceptable patency and limb salvage rates. The femorofemoral bypass is, however, more attractive, for it can be performed under local anesthesia if needed and does not involve the creation of the retroperitoneal incision necessary with the iliofemoral bypass.
Adolescent↗
Entering the ninth decade is not a contraindication for carotid endarterectomy.
The role of carotid endarterectomy (CEA) in stroke prevention is now better defined. However, its role in patients older than 79 years of age is controversial. This group of patients has been excluded in most clinical trials. In this study the authors reviewed their experience with CEA patients >79 years old. The records of all patients older than 79 years of age who underwent a CEA in a recent time period from January 1988 to December 1996 were retrospectively reviewed. Forty-one patients (31 men, 10 women) were identified by computer search. The indication for operation included transient ischemic attack in 12 (29.3%), amaurosis fugax in nine (22%), stroke in two (4.9%), and nonhemispheric symptoms in three (7.3%). Fifteen patients (36.6%) were asymptomatic. Medical risk factors included coronary artery disease in 26 (63.4%), hypertension in 22 (53.7%), and smoking in 12 (29.3%). The procedure was performed under EEG monitoring in all patients. General anesthesia was administered in 37 (90%) and regional anesthesia in four (10%). Shunts were used in four (10%) patients. The internal carotid artery was patched in 16 patients (39%). One patient (2.4%) developed a perioperative stroke and only one patient developed perioperative myocardial infarction (MI). None of the patients died within 30 days of surgery. In addition to the one MI case, five patients developed minor complications. The average length of time for stay after CEA was 3.4 days. Patients were followed up for an average of 20.7 months. Six patients died during follow-up. Four of those died from an MI and two from a stroke. The authors conclude that with proper selection of patients, CEA is safe in the octogenarian. Age alone should not be a contraindication for CEA.
Aged↗
Passing the torch.
Explore the source record for details and available documents.
Education, Medical, Continuing↗
Is color duplex surveillance of infrainguinal polytetrafluoroethylene grafts worthwhile?
BACKGROUND: Unlike vein bypasses, the role of duplex surveillance of infrainguinal prosthetic bypass grafts is controversial. The purpose of this study was to evaluate the adequacy of color duplex surveillance in identifying failing infrainguinal polytetrafluoroethylene (PTFE) bypass grafts and to assess its value in predicting continued bypass patency. METHOD: The surveillance data of primarily patent PTFE bypass grafts were compared with those of revised/occluded PTFE grafts. Ninety-five patients underwent 102 infrainguinal PTFE bypass grafts from January 1991 to December 1996 and were enrolled in a duplex surveillance program at 1 month postoperatively, every 3 months in the first year, every 6 months in the second year, and yearly thereafter. RESULTS: Seventy grafts remained primarily patent, 5 were revised and 27 occluded. There was no significant difference in the mean age, gender, indication for surgery, type of original procedure, or duration of follow-up between both groups. Four hundred and seven duplex surveillance data were available for analysis. Focal increase in peak systolic velocity (PSV) 3 x the adjacent segment or low flow manifested by PSV <45 cm/sec were considered abnormal. In the primarily patent group, 5 bypasses had abnormal duplex surveillance and were found to have no abnormality on angiogram and remained patent during the study period. In the revised/occluded group, duplex surveillance was abnormal in 8 bypasses. Twenty-four bypasses occluded without any predicting abnormalities on their last duplex examination, which was performed within 3 months from the occlusion in the majority of the patients. In the 27 occluded bypasses, no intervention was necessary following the occlusion in 7 grafts because of mild or no symptoms. Two patients were treated with a primary amputation and 2 had new bypasses. In 16 occluded grafts, salvage of the PTFE bypass was attempted. Ten of these grafts were patent at the end of the follow-up. The sensitivity of duplex surveillance was 25% with a positive predictive value of 61.5%. CONCLUSION: Duplex surveillance of infrainguinal PTFE bypass grafts has a low yield and is inadequate at predicting continued bypass patency.
Aged↗
Efficacy and safety of low molecular weight heparin (ardeparin sodium) compared to warfarin for the prevention of venous thromboembolism after total knee replacement surgery: a double-blind, dose-ranging study. Ardeparin Arthroplasty Study Group.
UNLABELLED: We performed a double-blind, randomized clinical trial to compare the efficacy and safety of three different subcutaneous (s.c.) low molecular weight heparin doses (ardeparin sodium 25, 35, or 50 anti-Xa U/kg twice daily [BID]) to adjusted-dose warfarin (international normalized ratio [INR] = 2.0 to 3.0), as venous thromboembolism prophylaxis after total knee replacement surgery. The primary endpoint was total venous thromboembolism prevalence, defined as deep vein thrombosis discovered at postoperative venography of the operated leg, or symptomatic, objectively-documented pulmonary embolism. Of 860 patients randomized, 680 (79%) had an evaluable venogram or pulmonary embolism. The total venous thromboembolism prevalence was significantly greater among patients prophylaxed with warfarin compared to ardeparin 50 BID (38% vs 27%, p = 0.019); the prevalence among ardeparin 25 BID (37%) and 35 BID (28%) patients was similar to warfarin and ardeparin 50 BID patients, respectively. Overt bleeding occurred in 22 (7.9%) ardeparin 50 BID patients compared to 12 (4.4%) warfarin patients (p = 0.08), and in seven ardeparin 25 and 35 BID patients each (5.2% and 5.0%, respectively). Compared to the warfarin group, blood loss was significantly greater in the ardeparin 50 and 25 BID groups, and not different in the ardeparin 35 BID group. CONCLUSIONS: Postoperative, unmonitored, fixed-dose ardeparin 50 anti-Xa U/kg s.c. BID is significantly more effective than adjusted-dose warfarin for this indication. Although overt bleeding among warfarin and ardeparin 50 BID patients did not differ significantly, ardeparin 50 BID patients had significantly greater blood loss. Ardeparin 35 anti-Xa U/kg s.c.BID may provide efficacy similar to ardeparin 50 anti-Xa U/kg s.c. BID but with reduced bleeding.
Adult↗
Cardiac screening tests prior to lower extremity revascularization: routine versus selective application.
Coronary artery disease (CAD) is the most important comorbidity associated with peripheral vascular disease. Consensus on the optimal approach to the cardiac evaluation of patients presenting for peripheral vascular operations has not been achieved. We developed a large experience with routine cardiac screening using dipyridamole thallium scintigraphy (DTS) and radionuclide ventriculography. The incidence of reversible ischemia on DTS and the subsequent documentation of severe CAD on coronary angiography was similar in vascular patients with a history of CAD (angina or myocardial infarction) and those with a negative CAD history. However, the analysis of overall risks and benefits does not support a recommendation for routine screening. We suggest that selection of patients for screening should be based on the estimated benefit of coronary revascularization for the individual patient considering both perioperative and long-term survival. In addition, screening is also considered if identification of unsuspected CAD will alter the decision to perform the proposed peripheral vascular operation. Thus, the older patient who requires an infrainguinal bypass for limb-threatening ischemia is unlikely to benefit from cardiac screening. Documentation of the extent of CAD with screening studies may be beneficial in younger patients or in patients with claudication.
Coronary Disease↗
Rabbit rectus femoris muscle for ischemia-reperfusion studies: an improved model.
The rabbit rectus femoris muscle was evaluated as a potential model for skeletal muscle reperfusion injury studies. Six white New Zealand rabbits were used. On one randomly selected hind limb, ischemia was induced by direct clamping of the rectus femoris muscle's vascular pedicle. On the other side, blood flow was interrupted by clamping the femoral artery above and below the origin of the vascular pedicle that supplies the rectus femoris muscle. The duration of normothermic ischemia was 4 hr and was followed by 24 hr of normothermic reperfusion. The interruption and restoration of blood flow was monitored using a laser flow meter. The rectus femoris muscles were weighed on a suspension spring balance prior to ischemia and at the end of reperfusion to estimate edema. The extent of muscle necrosis was determined using planimetry following staining with nitroblue tetrazolium. The muscle necrosis obtained by direct clamping of the vascular pedicle (66.9 +/- 14.3%) was significantly greater than that obtained by indirect clamping (18.6 +/- 11.4%) (P < 0.03 by t test). Unlike the indirect clamping technique, direct clamping achieved a good magnitude of muscle necrosis, thus allowing that specific model to be used in skeletal muscle reperfusion injury studies. The muscle weight gain observed in the direct clamping muscle group was 19.8 +/- 9.0% and was significantly greater than that observed in the opposite group being 6.3 +/- 6.5% (P < 0.05 by t test). The rabbit rectus femoris muscle is a suitable model for evaluating skeletal muscle reperfusion injury provided that direct clamping of the vascular pedicle is utilized.
Animals↗
Lateral approach to the popliteal and crural vessels for limb salvage.
Twenty-one patients underwent 23 bypasses for limb salvage via a lateral approach with subcutaneous graft tunneling. The reasons for utilizing a lateral approach were medial infection (10 bypasses), scarring from previous surgery (six), limited vein length available (three), prior local radiotherapy (two) and 'high risk' groin (two). The target artery was the anterior tibial in 16 cases, the peroneal in three, the above-knee popliteal in three and the dorsalis pedis in one. The median (range) follow-up was 22(<1-52) months. There were three early (within 30 days) and four late bypass occlusions, three of which occurred in previously revised bypasses and one in a non-compliant patient. The primary patency at 1 year was 61% and the secondary patency 86%. Only one amputation was required in the whole series. The lateral approach represents a simple solution to threatened limbs in otherwise difficult or complicated situations and may be the ideal approach for free vein grafts to the anterior tibial and distal peroneal arteries.
Aged↗
Selection of patients for cardiac evaluation before peripheral vascular operations.
PURPOSE: This study evaluated the value of preoperative cardiac screening with dipyridamole thallium scintigraphy and radionuclide ventriculography in vascular surgery patients. METHODS: From July 1, 1989, to Dec. 31, 1991, we routinely (irrespective of the patient's cardiac history or symptomatology) performed dipyridamole thallium scintigraphy (DTS) and radionuclide ventriculography (RVG) in 394 patients being considered for an elective vascular operation. Patients with reversible defects on DTS underwent coronary arteriography. RESULTS: DTS results were normal in 146 patients (37%), showed a fixed defect in 75 (19%), and showed a reversible defect in 173 (44%). Patients with and without a history of angina or myocardial infarction had identical rates of reversible defects. Normal left ventricular function (> 50%) was noted in 76% of the patients; 17% had moderate dysfunction (35% to 50%) and 7% had a low ejection fraction (< 35%). The finding of severe coronary artery disease led to cardiac revascularization in 17 patients who had no prior history of cardiac disease and in 13 patients with a history of angina or myocardial infarction. Two deaths and nine major complications were associated with coronary arteriography and cardiac revascularization. Vascular procedures (144 aortic, 53 carotid, 146 infrainguinal) were ultimately performed in 343 patients, with a mortality rate of 1.7% (3.5% aortic, 0% carotid, and 0.7% infrainguinal bypass). The nonfatal perioperative myocardial infarction rate was 2.0%. We monitored all 394 patients for cardiovascular events, with a mean follow-up of 40 months. Patients who underwent cardiac revascularization had a 4-year survival rate of 75%, which was similar to those with a normal DTS. Late cardiac events were significantly more frequent in patients who had either a reversible DTS or RVG < 35%. CONCLUSIONS: Routine cardiac screening of vascular surgery patients had similar impact on patients irrespective of their prior history or current symptoms suggesting coronary artery disease. Routine screening did not result in substantial benefit. Screening studies such as DTS or RVG may be most useful as part of an overall risk versus benefit assessment in patients without active symptoms of coronary artery disease who have less compelling indications for vascular intervention (claudication, moderate-sized aortic aneurysms, or asymptomatic carotid disease).
Aged↗
The aortic polytetrafluoroethylene graft: further experience.
OBJECTIVES: We analysed our results with the use of aortic polytetrafluoroethylene PTFE grafts over the last 7.5 years. A historical comparison was also made between the results with non-stretch PTFE (NS-PTFE) (1987-91) and stretch PTFE (S-PTFE) grafts (1991-94). MATERIALS: 244 infrarenal aortic replacements or bypasses with PTFE grafts were performed at the University of Iowa Hospitals and Clinics from January 1987 to June 1994. Infrarenal aortic replacement was indicated for aortic aneurysmal disease in 192 patients (elective 151, symptomatic 20, ruptured 21) and bypass for aorto-iliac occlusive disease in 52 patients (disabling claudication 28, limb salvage 24). Patients ranged in age from 37 to 93 years (mean 68 years). There were 161 males and 83 females. Medical risk factors included hypertension (55%), coronary artery disease (31%), COPD (23%), diabetes mellitus (12%) chronic renal failure (9%), and smoking (61%). Aortic replacement or bypass was done with a NS-PTFE graft in 108 patients (44%) and a S-PTFE graft in 136 patients (56%). Postoperative ultrasound (US) scans and/or CT-studies were available in 40 patients with NS-PTFE and 26 patients with S-PTFE grafts. MAIN RESULTS: The 30 day operative mortality was: elective AAA patients (1.3%), symptomatic AAA patients (10%), ruptured AAA patients (48%), limb salvage patients (4.1%) and disabling claudication patients (0%). Graft related complications included five graft limb thromboses (4 NS-PTFE, 1 S-PTFE). Two thromboses occurred perioperatively and the three others at 24, 28 and 30 months postoperatively. Two other graft related complications included a mixed pseudomonas and streptococcus groin infection with a culture negative perigraft fluid collection occurring 3 weeks following surgery (NS-PTFE), and distal aortic anastomotic suture line bleed on the first postoperative day following replacement of a ruptured AAA with a S-PTFE graft. Based on US and/or CT imaging studies, the mean internal diameters of the bodies of 40 NS-PTFE and 26 S-PTFE grafts were 11% and 10% greater than the manufacturer's specified sizes at a mean follow-up duration of 36 and 10 months respectively. CONCLUSIONS: These data reveal that a PTFE graft performs satisfactorily in the aortic position with minimal adverse clinical sequence over a 7.5 year period. Continued long term follow up data will determine the ultimate suitability of aortic PTFE grafts.
Adult↗
The management of extrahepatic portal vein aneurysms: observe or treat?
A case of a 70 year old man who was found to have an extrahepatic portal vein aneurysm during an evaluation for hematuria is reported. Extrahepatic portal vein aneurysms are rare with only twenty cases reported in the literature. Typically, patients present with hemorrhage requiring surgical exploration or the aneurysm is discovered during evaluation of another abdominal process. Management includes careful follow-up in the asymptomatic patient without underlying liver disease or portal hypertension.
Abdominal Pain↗
Effects of the lazaroid U74389G (21 aminosteroid) on skeletal muscle reperfusion injury in rabbits.
The purpose of this experiment was to evaluate the effects of the aminosteroid U74389G on skeletal muscle reperfusion injury in rabbits. In 24 white New Zealand rabbits (weighing 7.0-8.0 lb), the rectus femoris muscle on both sides was completely isolated on a single vascular pedicle (artery and vein) and a major accessory vein. All muscles were weighed using a suspension spring balance and then underwent 4 hours of normothermic ischemia followed by 24 hours of reperfusion. Muscle ischemia was induced by the application of atraumatic vascular clamps to the vascular pedicles. Complete muscle ischemia and reperfusion were documented by a laser flow meter. The animals were divided into three groups; Group I (n = 8) served as control, Group II (n = 8) received an i.v. bolus of U74389G (1.5 mg/kg) five minutes prior to ischemia, Group III (n = 8) was given the same dose of lazaroid five minutes prior to reperfusion. Muscle biopsies were obtained before ischemia and after reperfusion for quantification of myeloperoxidase (MPO) activity. At the completion of reperfusion, the muscles were excised, weighed and cut into slices along the longitudinal axis and then incubated for 30 minutes in 0.05% nitroblue tetrazolium. Areas of necrosis were determined by computerized planimetry. The following results indicate that reperfusion muscle necrosis in rabbits is significantly decreased by the administration of the lazaroid U74389G. Leukocyte sequestration was not affected by the lazaroid administration. These beneficial effects were observed whether the lazaroid was administered prior to ischemia or prior to reperfusion and were independent of leukocyte sequestration.
Animals↗
Revascularization of the ischemic diabetic foot using popliteal artery inflow.
Between March 1988 and June 1994, 35 popliteal to distal artery vein bypasses were done in 32 diabetic patients. There were 16 males and 16 females with an average age of 60 years. Eighteen patients (56%) had insulin dependent diabetes mellitus. Medical risk factors included coronary artery disease (CAD) in 15 (47%), hypertension in 15 (47%), chronic renal failure (CRF) in 9 (28%), and cigarette smoking in 10 (31%). Indications for revascularization were: non-healing ulcerations in 18 (51%), gangrene in 15 (43%), and rest pain in 2 (6%). The distal anastomosis was to the posterior tibial artery in 9, anterior tibial artery in 8, dorsalis pedis artery in 10 and peroneal artery in 8 cases. All the bypasses were done with autogenous saphenous veins (in-situ 11, reversed 17, and free non-reversed 7). The limbs were graded into three groups based on the preoperative angiographic evaluation of their pedal arch: patent arch (Grade "0"), partial occlusion of the arch (grade "1.5") and little or no arch visualized (Grade "3"). Eight limbs had Grade "0", 16 had Grade "1.5" and 11 had Grade "3" pedal circulation. Bypass follow up was done by clinical exam and color duplex surveillance (CDS) for a mean duration of 24 months. CDS identified 4 failing bypasses which were surgically revised and have subsequently remained patent. There were 3 bypass occlusions which resulted in a major amputation in 2 patients. Three additional major amputations were performed for persisting infection despite a patent bypass. By life table analysis the cumulative primary & secondary patency and limb salvage rates for this group of diabetic patients were 75% at 2 years, 89% at 3 years and 82% at 3 years respectively (S.E. < 10%). The 3 bypass occlusions, which occurred at 1 week, 5 weeks, and 20 months, were in patients with both CRF and Grade "3" foot circulation (significantly different outcome compared to the rest of the group, by chi 2 test, p < 0.05). Good results can be achieved in the majority of diabetic patients undergoing short popliteal-distal bypasses. However, the combination of chronic renal failure and very limited foot circulation (Grade "3") has a significant adverse outcome.
Diabetic Foot↗
Should all in situ saphenous vein bypasses undergo permanent duplex surveillance?
OBJECTIVE: To evaluate the need for color duplex surveillance (CDS) for pure in situ bypasses beyond 6 months. DESIGN: We reviewed our in situ surveillance data from August 1987 to April 1994. Lower-extremity revascularization was performed using 245 pure in situ greater saphenous vein bypasses in 219 patients. The CDS of the entire bypass and inflow and outflow arteries was done prior to discharge, at 1 month, every 3 months in the first year, every 6 months in the second year, and annually thereafter. A peak systolic velocity of less than 45 cm/s throughout the bypass or a velocity ratio of greater than 3 (peak systolic velocity at the stenosis divided by peak systolic velocity at an adjacent normal bypass segment) were defined as abnormal during the review of this patient subset. The outcomes were analyzed. Patency and limb salvage rates were calculated by life-table analysis. PATIENTS: The mean age of this population (120 men and 99 women) was 67 years (range, 32 to 97 years). We analyzed all bypasses that were subjected to CDS for 6 months or more and identified 171 such bypasses. These bypasses were followed up for a mean duration of 30 months (range, 6 to 82 months). RESULTS: The primary and secondary patency and limb salvage rates at 5 years were 60.4%, 89%, and 92.1%, respectively (SE, < 10%). During the first 6 months of surveillance, 54 bypasses had abnormal CDS findings, and 117 had normal CDS findings. Arteriography was performed on 42 of these bypasses with abnormal CDS findings, and 37 had significant findings requiring direct surgical or endovascular intervention. Only two of 117 bypasses that had normal CDS findings for up to 6 months had to be revised later, compared with 43 of the 54 bypasses with abnormal CDS findings prior to 6 months, which were occluded or were revised (significantly different by chi 2 test [P < .001]). CONCLUSIONS: Vigorous CDS of pure in situ bypasses for up to 6 months is useful to detect bypass-threatening lesions. Continued CDS of a normal in situ bypass after 6 months may not be justifiable, as the incidence of lesions requiring later revision is minimal.
Adult↗
Late results of a prospective study of direct intra-arterial urokinase infusion for peripheral arterial and bypass graft occlusions.
The outcome of 72 direct intra-arterial urokinase infusions was studied prospectively. Thirty four were performed for native arterial occlusion and 38 for bypass graft occlusion; the immediate success rates were 67.5 and 84% respectively. The overall incidence of complications was 26%. Median follow-up was 36 (range 1-60) months. Seventeen patients (27%) died during follow-up; nine (14%) required a major amputation. Among patients with native arterial occlusion, 29% had no adjunctive procedure after thrombolysis; of these patients, 85% remained patent at a median of 21 (range 3-42) months. Among bypass occluded patients, only two (6%) had no lesion revealed after successful lysis; both bypasses remain patent at 54 and 58 months respectively. For patients treated with balloon angioplasty immediately after successful thrombolysis, 62% with native arterial occlusion remained patent at a median of 39 (range 2-60) months, whereas only 27% of bypass occlusion patients were patent at a median of 11 (range 2-40) months. Of patients requiring a surgical procedure after thrombolysis, 23 new bypasses (15 vein, eight prosthetic) were placed (nine in native arterial occlusion patients, 14 in bypass occlusion patients). In addition, there were 15 other surgical procedures, including six thrombectomies, four vein patch angioplasties, four vein jump grafts and one endarterectomy. The primary and secondary patencies for the 15 new vein bypasses placed were 81 and 88% respectively at a median follow-up of 36 months. Good immediate results were experienced with urokinase thrombolysis for peripheral arterial and graft occlusions. However, multiple adjunctive procedures were required to maintain patency.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
A comparative evaluation of externally supported polytetrafluoroethylene axillobifemoral and axillounifemoral bypass grafts.
PURPOSE: We analyzed a current 78-month experience with externally supported (ringed) polytetrafluoroethylene (PTFE) axillobifemoral (AxBF) and axillounifemoral (AxUF) bypass grafts to address the controversy about whether the addition of a femorofemoral limb to an axillofemoral bypass graft improves the patency results. METHODS: Between January 1988 and June 1994, 36 AxBF and 22 AxUF externally supported PTFE ringed bypass grafts were performed at our institution. The age of the patients in the AxBF group was 67 +/- 11 years and 69 +/- 11 years in the AxUF group. The male/female ratio was 22:13 (AxBF) and 8:9 (AxUF). In 71% of cases (29/36 AxBF, 12/22 AxUF), the operations were performed for aortoiliac atherosclerotic occlusive disease in patients with significant medical risk factors or a "hostile" abdomen. The remaining 29% were patients requiring revascularization during treatment of an infected aortic graft. Bypass patency was assessed in the follow-up period by clinical evaluation, color-flow duplex imaging, or segmental limb pressure measurements. RESULTS: There was no significant difference in the 30-day operative mortality rate for all AxBF bypasses (11%) and all AxUF bypasses (6%) (p = 0.89 by chi-squared testing). The primary and secondary patency rates for the whole group of bypasses were 80% and 89% at 3 years, respectively (SE < 0.1). Between the AxBF and AxUF groups, there were no significant differences in either primary patency (80% for each group) or secondary patency (91% in AxBFs vs 85% in AxUFs) (SE < 0.1) at 2 years (Wilcoxon rank sum test). CONCLUSIONS: These data show no differences in the patency of externally supported PTFE AxBF and AxUF bypass grafts up to 2 years after implantation.
Aged↗
Comparative efficacy and complications of vena caval filters.
PURPOSE: A variety of vena caval filters (VCFs) are available for usage. The choice of filter type depends on physician preference and certain patient variables. An evaluation of the different VCFs used in our institution was done to compare their efficacy and complication rates. METHODS: The medical records of all patients who underwent insertion of a VCF from January 1987 to June 1993 at the University of Iowa Hospitals & Clinics and the affiliated Veterans Administration Medical Center were reviewed. One hundred ninety-nine VCFs were placed in 196 patients (123 males, 73 females), with a mean age of 61 years (range 13 to 87 years). Thirty-five (18%) VCFs (30 stainless steel Greenfield filters [SGFs] and five titanium Greenfield filters with modified hook [TGF-MHs]) were inserted in the operating room via an open technique. The remaining 164 VCFs (82%) were inserted in the radiology suite by a percutaneous technique (38 SGF, 23 TGF-MH, 51 Vena Tech filters [VTFs], 48 Bird's nest filters [BNFs] and 4 Simon Nitinol filters). Thromboembolic risk factors in these 196 patients included malignancy (99), trauma (21), recent surgery (27), cerebrovascular accident with paralysis (6), and miscellaneous conditions (43). Indications for VCF placement included a contraindication to anticoagulation (92), complication of anticoagulation (44), failure of anticoagulation (26), prophylaxis (31), adjunct to pulmonary embolectomy (1), noncompliance (1), hemodynamically unstable patient (1), and prior VCF complication (3). Mean follow-up of the patients was 12 months (range 0 to 87 months). Because there were only four Simon Nitinol filters inserted during the study period, they were excluded from further analysis. RESULTS: A comparative analysis revealed that there was a significantly higher incidence of symptomatic IVC thrombosis with the use of the BNF (n = 7) (14.6%) versus the SGF (n = 0) (0%), TGF-MH (n = 1) (3.6%), or VTF (n = 2) (4%) (p < 0.05 by chi-squared testing). The VCF-related mortality rate was also higher with the BNF (n = 5) (10.9%) versus the SGF (n = 1) (1.5%), TGF-MH (n = 1) (3.6%), or VTF (n = 0) (0%) (p < 0.05 by chi-squared testing). However there was no significant difference in the occurrence of clinically apparent recurrent pulmonary embolism during follow-up between the four different filter types (2 [4.2%] BNF, 3 [4.4%] SGF, 1 [3.6%] TGF-MH, and 1 [2%] VTF). CONCLUSION: These data indicate that the use of the BNF was associated with increased morbidity and mortality rates compared with the use of the SGF, TGF-MH, and VTF filters.
Adolescent↗