Biomedical subjects

E Criado

Publications and source records attributed to E Criado.

At least 37 records · Page 2Linked to original sources

PubMed1995

Physiologic variations in lower extremity venous valvular function.

We conducted this study to investigate the physiologic variations in venous valvular function and calf muscle pump function that occur in normal limbs after prolonged stationary standing. Twenty-two limbs from 11 healthy volunteers were studied after a brief period of activity and after 4 to 6 hours of stationary standing. Vein diameter, peak reflux flow velocity (PRFV), and valve closure time (VCT) were measured with duplex scanning in the standing position in the common femoral vein (CFV), superficial femoral vein (SFV), popliteal vein (POP), proximal greater saphenous vein (GSV), and greater saphenous vein at the knee (kGSV). Pneumatic rapid inflation-deflation cuffs were used to elicit reflux. Vein cross-sectional area (VA) and peak reflux volume (PRVol) were calculated. Venous volume (VV), venous filling index (VFI), ejection fraction (EF), residual volume fraction (RVF), and outflow fraction (OF) were measured with air plethysmography in all limbs. After stationary standing, there was no significant change or trend toward an increase in diameter or VA in any of the deep veins and there was no change in the PRFV or VCT. In the proximal GSV there was a significant increase in diameter (p = 0.0001) and VCT (p = 0.048) without a change in PRFV. No significant changes were noted in the kGSV. In the GSV the PRFV was significantly lower (p < 0.05) and the VCT significantly shorter (p < 0.05) compared with the SFV and POP but values were no different from those in the CFV. The PRFV was significantly higher in the SFV (p < 0.0001) and the POP (p < 0.002) compared with that in the CFV.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1995

Extrathoracic reconstruction of arterial occlusive disease involving the supraaortic trunks.

PURPOSE: The purpose of this study was to review the various extrathoracic reconstruction options in patients with occlusive disease of the supraaortic trunks and to define the efficacy of these procedures in maintaining graft patency and relieving symptoms. METHODS: Forty-four consecutive patients underwent 47 extrathoracic bypass procedures of the supraaortic trunks for correction of symptomatic subclavian (SCA), common carotid (CCA) or innominate (INA) artery occlusive disease between July 1975 and May 1994. SCA stenosis (n = 27) was associated with upper extremity claudication (55%), vertebrobasilar insufficiency (15%), or both (30%). CCA stenosis (n = 14) was accompanied by hemispheric symptoms in 86% and global ischemia in 14%, whereas INA stenosis (n = 3) was associated with transient ischemic attacks (67%) and right arm ischemia (33%). RESULTS: SCA revascularization included carotid-subclavian or carotid-axillary bypass (n = 19), axilloaxillary bypass (n = 8), and subclavian-carotid transposition (n = 3). CCA reconstructions included subclavian-carotid (SC) bypass (n = 13) and carotid-carotid bypass (n = 1). INA procedures included three axilloaxillary bypasses. Six patients had an associated carotid endarterectomy, and three underwent concomitant vertebral artery transpositions. Intraluminal shunts were not routinely used. Vein was used as a conduit in five procedures, and a prosthetic graft (23 Dacron, 16 polytetrafluoroethlyene) was used in the remainder. The average postoperative intensive care unit and hospital and hospital stay were 1 and 5 days, respectively. Follow-up was available in 43 of 44 patients (mean = 26.2 months). The perioperative mortality rate was 2.2% (one axilloaxillary). There were five graft occlusions in procedures involving the axillary artery (3 of 11 axilloaxillary, 2 of 7 carotid-axillary) as compared with one of 29 thromboses when the operation was confined to the supraclavicular fossa (p < 0.05) Relief of symptoms was achieved in all patients with patent grafts. There were no perioperative strokes in the series. Other complications included one brachial plexus neuropraxia (axilloaxillary) and four patients with phrenic nerve neuropraxia. CONCLUSION: Extrathoracic revascularization of the supraaortic trunks is well tolerated and durable when operations are confined to the supraclavicular fossa and do not involve the axillary artery.

Adult↗

PubMed1995

An aortic aneurysm model for the evaluation of endovascular exclusion prostheses.

PURPOSE: The purpose of this study was to develop an aortic aneurysm (AA) model with a predictable tendency for rupture for the evaluation of the efficacy of endovascular prostheses in preventing rupture and their long-term outcome after implantation. METHODS: An infrarenal AA measuring two to three times the diameter of the proximal aorta was created in 18 dogs with a full-thickness patch of jejunum. Seven dogs were allowed to survive without aneurysm exclusion. In 11 dogs the aneurysm was immediately excluded with a stented 8 mm Dacron graft mounted in a 14F delivery system introduced through the femoral artery with aortographic guidance. The pressure differential between the aorta and the excluded aneurysm was measured, and angiography, necropsy, and histologic examination were performed at 3- and 6-month survival. RESULTS: All animals survived aneurysm implantation. Without aneurysm exclusion, six dogs died of rupture within 1 to 6 days of surgery. In three dogs the exclusion failed because of graft-to-aorta size mismatch or misplacement demonstrated on angiography and by a low pressure differential between the aorta and the aneurysm (< 5 mm Hg); all three dogs died of rupture within 4 days. In eight dogs the aneurysm was successfully excluded on the basis of angiography results, with a mean aorta-to-aneurysm pressure differential of 51 mm Hg. Two dogs were killed at 1 and 6 days after surgery because of paraplegia produced by graft thrombosis because of kinking but without evidence of aneurysm rupture. Six dogs survived on a long-term basis, and angiography and necropsy performed at 3 and 6 months revealed patent grafts without migration, reduction in aneurysm size, no flow in the excluded lumbar arteries in five of six animals, and complete incorporation of Dacron graft and stents. No evidence of graft infection was found in any animal. The survival rate was significantly better (p < 0.023) in dogs with successfully excluded aneurysms (n = 6) compared with that in dogs without exclusion or with failed aneurysm exclusion (n = 7). CONCLUSION: This aneurysm model demonstrates that without effective aneurysm exclusion all animals die of rupture and that successfully placed endovascular prostheses can prevent AA rupture with long-term graft patency and stability. Endovascular aortic Dacron grafts in dogs undergo complete incorporation at 3 months from implantation. This aneurysm model is useful for the evaluation of endovascular devices designed for the treatment of AAs.

Animals↗

PubMed1995

Transbrachial endovascular exclusion of an axillary artery pseudoaneurysm with PTFE-covered stents.

PURPOSE: Endovascular exclusion of arterial injuries associated with arteriovenous fistulas and pseudoaneurysms has only recently been described using various stent-graft prostheses. This report details a transbrachial technique used to exclude an axillary artery pseudoaneurysm developing at the axillary anastomosis of an axillofemoral graft. METHODS AND RESULTS: Thin-walled polytetrafluoroethylene was expanded with an angioplasty balloon catheter and used to cover standard Palmaz stents. Two covered stents were delivered under fluoroscopic guidance via open brachial artery access to the site, resulting in complete exclusion of the pseudoaneurysm. Follow-up duplex scanning confirmed aneurysm exclusion 3 months postprocedure. CONCLUSIONS: This technique can be applied in arteries of different sizes and lengths, using currently available materials. However, the long-term behavior of these devices in the arterial tree must be determined before their widespread use can be recommended for most indications.

Aged↗

PubMed1994

Proximal venous outflow obstruction in patients with upper extremity arteriovenous dialysis access.

To evaluate the impact of central venous obstruction on upper extremity hemodialysis access failure, we retrospectively analyzed our recent experience in managing this problem. We reviewed 158 upper extremity hemodialysis access procedures performed in 122 patients during a 1-year period. Fourteen (11.5%) patients had central vein obstruction as the cause of severe arm swelling, graft thrombosis, or graft malfunction. All 14 patients had had bilateral temporary subclavian vein dialysis catheters and failed upper extremity arteriovenous access. Seventeen lesions were treated in 14 patients including eight subclavian vein occlusions, six subclavian vein stenoses, two internal jugular vein stenoses, and one superior vena cava stenosis. Twenty-one procedures were performed including 17 percutaneous transluminal balloon angioplasties (PTAs) with stent placement in 13, two axillary to innominate vein bypasses, and two axillary to internal jugular vein bypasses. All patients had resolution of symptoms. Thirteen (76%) PTAs were initially successful but in four (24%) cases it was impossible to recanalize the vein. Eight (47%) PTAs provided functional hemodialysis access for 2 to 9 months, two (12%) restenosed at 3 and 10 months and were successfully redilated, two occluded at 2 and 4 months and were unable to be recanalized, and one failed immediately after a successful PTA. Four PTA failures were followed by venous bypass, which remained patent and provided functional access 7 to 13 months after surgery. Of nine stenotic venous lesions six (67%) were successfully dilated without restenosis, whereas of eight occluded veins only two (25%) were successfully treated without recurrence. Temporary central hemodialysis catheters produce a significant number of symptomatic central vein obstructions in patients with upper extremity arteriovenous access.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗

PubMed1994

Use of the descending thoracic aorta as an inflow source in aortoiliac reconstruction: indications and long-term results.

Bypass grafting from the descending thoracic aorta to the iliac or femoral artery is an underutilized procedure; fewer than 200 cases were reported in the past 30 years. Over the last decade we performed 32 bypasses to the femoral iliac or popliteal arteries using the descending thoracic aorta as the inflow source. In 19 (59%) patients the procedure was a primary aortic reconstruction, whereas in 13 (41%) it was secondary. The 30-day in-hospital mortality rate was 6.2%. Primary graft patency was 86% (+/- 7.8) at 2 years. To obtain a meaningful long-term patency analysis, we combined our experience with that reported in the literature during the same period. Follow-up data were available in 146 patients in whom the mean follow-up time ranged from 15 to 53 months. The operation was a secondary aortic reconstruction in 84 (58%) patients and was a primary procedure in 62 (42%). Reasons for the selection of the descending thoracic aorta as the inflow source included previous abdominal aortic graft failure in 56 (38%) patients, abdominal aortic graft infection in 26 (18%), unfavorable abdominal conditions in 30 (21%), and miscellaneous causes in 34 (23%). The 30-day in-hospital mortality rate for the collective experience was 5.5%. Life-table analysis of the collective primary graft patency rate was 88.3% (+/- 2.9) at 1 year, 81% (+/- 4.3) at 3 years, and 72.7% (+/- 8.5) at 6 years. Secondary graft patency for the collective experience was 93.1% (+/- 2.3) at 1 year, 88.2% (+/- 3.7) at 3 years, 82.7% (+/- 7.3) at 6 years, and 82.7% (+/- 10) at 8 years. Patient survival was 67.5% (+/- 6.9) at 5 years and 55.4% (+/- 9.9) at 7 years. These data suggest that bypass from the descending thoracic aorta to the iliac or femoral arteries offers low mortality and excellent durability and should be considered as the procedure of choice for secondary or extra-anatomic aortoiliac reconstruction.

Aged↗

PubMed1994

Management of failed and infected axillofemoral grafts.

PURPOSE: The purpose of this study was to review the treatment of patients with failed or infected axillofemoral bypass grafts and to determine the efficacy of remedial procedures in maintaining graft patency and limb preservation. METHODS: Thirty-four patients with 37 failed or infected axillofemoral grafts were retrospectively reviewed. In nine cases there was no attempt at revascularization, and in the remaining 28 cases, a total of 52 remedial procedures was performed. Nine were performed in patients with graft infection and 43 in patients with graft thrombosis. In patients with axillofemoral graft failure, 21 thrombectomies, 13 graft revisions, and 9 secondary reconstructions were performed. Eighty-eight percent of patients were monitored at least 2 years or until graft failure. RESULTS: Eight of nine patients receiving no remedial procedure required major amputation. The limb salvage rate was 64% +/- 11% at 30 months in the 25 patients undergoing remedial procedures. Twenty-eight percent of failed axillofemoral grafts remained patent at 2 years after initial failure with single or multiple thrombectomies or revisions. Life-table primary patency after secondary reconstructions (81% +/- 10.9% at 24 months) was significantly better than after thrombectomy alone (10% +/- 4.2% at 24 months) or graft revision (16% +/- 10.6% at 24 months) by log-rank test (p < 0.001 and p < 0.005, respectively). Patients undergoing reconstruction with descending thoracic aorta to femoral artery bypass had an 89% +/- 11% patency rate at 24 months. Graft infection resulted in a perioperative mortality rate of 22% and amputation in 57% of survivors. CONCLUSION: Axillofemoral graft failure most often results in limb loss without remedial procedures. Thrombectomy and revision procedures had poor long-term patency rates and salvaged only a minority of grafts despite multiple procedures. Reconstruction by use of an alternate source of inflow such as the descending thoracic aorta resulted in better long-term patency rates in patients well enough to tolerate a major reoperative procedure.

Amputation, Surgical↗

PubMed1993

Progression of occlusive disease following femorofemoral crossover bypass graft.

Progression of distal disease is considered the most common cause of femorofemoral artery crossover bypass graft (FFBPG) failure. Twenty-seven patients with patient grafts (mean 53 months) were evaluated with segmental Doppler and duplex scan arterial studies for evidence of disease progression. In the early postoperative period (compared with preoperative levels), 26 patients (95.3%) showed a significant improvement (> 0.1) in the recipient limb ankle-brachial index (ABI) (mean increase of 0.38; SD = 0.24) and/or ankle spectral arterial waveform. However, there was a statistically significant decrease (p = 0.0001) in the donor limb ABI, and 12 patients (44.4%) had a > 0.1 deterioration. On long-term follow-up (compared with preoperative levels) this difference was no longer significant (p = 0.49); only seven donor limbs remained with a > 0.1 decrease in ABI. The recipient limbs maintained a significant improvement (> 0.1) in the ABI compared to preoperative levels (p < 0.0001; mean of 0.39; SD = 0.16) except for three limbs that had decreased by 0.1. However, eight patients (29.6%) developed an increase in their donor common femoral artery acceleration time > 133 msec and/or increased blood flow velocity without a simultaneous significant decrease in their recipient limb ABI. In the latter group the preoperative donor limb common femoral artery acceleration time and ABI and the immediate postoperative change in donor limb ABI were not significantly different (p > 0.05) than in the remaining patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Arterial Occlusive Diseases↗

PubMed1993

Femorofemoral bypass graft: analysis of patency and factors influencing long-term outcome.

PURPOSE: To evaluate the results of femorofemoral bypass graft (FFBPG), we analyzed 110 consecutive FFBPGs performed at our institution during an 11-year period. METHODS: In 62 (56%) patients the indication for surgery was claudication and in 48 (44%) patients rest pain or tissue loss. In 42 patients the superficial femoral artery (SFA) was occluded. A preoperative percutaneous transluminal balloon angioplasty (PTA) was performed in 24 (22%) patients to correct a significant donor iliac artery stenosis. In 48 (44%) patients a total of 54 arterial procedures were performed simultaneously with FFBPG. RESULTS: After surgery 75 (68%) patients were moderately or markedly improved, whereas 20 (18%) were minimally improved, unchanged, or worse, including 7 (6%) with hemodynamic failures. The in-hospital mortality rate was 4.5%. Actuarial patient survival rate was 70% +/- 8.6% at 6 years. The actuarial primary graft patency rate was 83% +/- 4.2% at 1 year, 71% +/- 6.9% at 3 years, 60% +/- 8.3% at 5 years, and 51% +/- 9.6% at 6 years. Age, sex, and race of the patient did not influence graft patency. Grafts placed for limb-threatening ischemia or in patients with SFA occlusion had a similar patency rate compared with those placed for claudication or in patients with patient SFA. The overall limb preservation rate was 83% +/- 7.3% at 5 years but was only 64% for patients who underwent operation for limb-threatening ischemia. CONCLUSIONS: In conclusion, FFBPG offers moderately low long-term patency in a population with limited survival. Outflow procedures performed concomitantly with FFBPG seemed to compensate for the negative impact on graft patency rate of ipsilateral SFA occlusion and limb-threatening ischemia. Limb-threatening ischemia, however, carried a significantly higher (p < 0.05) amputation rate. The influence of preoperative donor iliac artery percutaneous transluminal balloon angioplasty on FFBPG patency remains unclear.

Adolescent↗

PubMed1992

Heterotopic hindgut duplication: a cloacal remnant associated with exstrophy of the bladder.

Lower hindgut duplications, although very rare, usually present as a cystic mass located posterior to the rectum and confined to the pelvis. Hindgut duplications are often associated with genitourinary or spinal anomalies. We describe a neonate with a previously unreported heterotopic colonic duplication presenting as an exophytic perineal mass associated with classic bladder exstrophy. The embryonic significance of these anomalies is discussed.

Abdominal Neoplasms↗

PubMed1992

Descending thoracic aorta-to-iliofemoral artery bypass as an alternative to aortoiliac reconstruction.

During the last 3 decades subcutaneous extraanatomic bypass, despite its limited durability, has been the favored alternative to infrarenal aortofemoral bypass. Meanwhile, the descending thoracic aorta has been scarcely used as an inflow source for aortoiliac reconstruction. Over the past 8 years we performed 16 bypasses from the descending thoracic aorta to the iliofemoral vessels for occlusive disease. Our experience combined with that found in the English-language literature totaled 141 patients. In 79 patients (56%) the indication for surgery was failure or infection of an abdominal aortofemoral graft. Previous abdominal operations, sepsis, radiation therapy, the presence of abdominal stomas, or an unsuitable infrarenal aorta were the indications in the remaining cases. The combined operative mortality rate was 6.4%. The life-table primary graft patency was 98% at 1 year, 88% at 2 years, and 70.4% at 5 years. Bypass from the descending thoracic aorta to the iliofemoral artery uses an inflow source superior to other extraanatomic reconstructions, does not require aortic cross-clamping, avoids the abdominal cavity, and places the graft remote to the skin and intestine. The operative mortality and patency rates compare favorably to those of other extraanatomic or remedial aortic reconstructions. Descending thoracic aorta to iliofemoral artery bypass is a superb alternative to abdominal aortofemoral bypass, carries a low mortality rate, has an excellent short-term patency, and features unique characteristics for long-term durability.

Adult↗

PubMed1992

Long term results of percutaneous catheter drainage of pancreatic pseudocysts.

Percutaneous catheter drainage (PCD) has become an established and often preferred alternative to surgical treatment in the management of pancreatic pseudocysts. However, the long term results of percutaneous drainage of pancreatic pseudocysts remain uncertain. In an effort to determine the long term outcome of this therapy, 42 patients undergoing PCD of a pancreatic pseudocyst were analyzed retrospectively. Forty-two pancreatic pseudocysts were drained percutaneously in 42 patients. Sixty-seven percutaneous drainage procedures were performed--22 patients underwent one, 15 had two and five patients required three procedures. Percutaneous drainage was considered not to be effective when the pseudocyst persisted or when it recurred after initial resolution. Twenty-three pseudocysts were infected at the time of drainage and 19 were not infected. In 30 patients, the cause of the pseudocyst was alcoholic pancreatitis. There were no deaths related to the procedures and seven complications occurred, including hemorrhage, pancreatic fistula and empyema. Mean follow-up evaluation time of the patients was ten months. In nine patients, the pseudocyst was successfully drained and resolved. There were 33 treatment failures, among which 26 pseudocysts failed to resolve and seven recurred after initial resolution. Eventually, 25 patients underwent a surgical procedure, 20 for persistent pseudocyst and five for recurrence. Using contingency table analysis, the size of the pseudocyst, amount of fluid drained, amylase concentration in the aspirate, presence of infection, number of drainage procedures performed and duration of catheter drainage had no influence on the likelihood of success in long term pseudocyst resolution after PCD. Pseudocysts not related to alcoholic pancreatitis seemed to be less likely (p < 0.05) to resolve with percutaneous drainage than those caused by alcohol. PCD is a safe and valuable procedure in the acute management of patients with pancreatic pseudocyst. However, the current data suggest that despite early success with percutaneous drainage, the lack of resolution and recurrence rate of pancreatic pseudocyst is high. Therefore, it should not be considered as the definitive form of therapy in most patients. Close surveillance of patients undergoing percutaneous drainage and communication between surgeons and radiologists are critical in the management of pancreatic pseudocysts.

Adult↗

PubMed1992

The course of severe foot infection in patients with diabetes.

Infection of the foot is a limb threatening condition for patients with diabetes mellitus. Identification of patients with diabetes and severe infection of the foot most likely to benefit from early revascularization or major amputation would improve the results of a treatment policy to prevent limb loss and avoid futile delays in amputation. During a nine year period, 79 diabetic patients underwent emergency procedures for severe infection of the foot during the initial hospitalization period. None of the patients underwent arterial reconstruction. Eventually, 21 of the patients required a major amputation, eight during the initial hospitalization and 13 on a subsequent admission. Stepwise discriminant analysis of clinical independent variables revealed that the patients most likely to require a major amputation during the initial hospitalization were those with an absent dorsalis pedis pulse and a polymicrobial infection (p = 0.018). The overall amputation rate (immediate or subsequent amputation) was higher for patients of either sex with nonpalpable pedal pulses when compared with those with at least one palpable pulse (p less than 0.05). Males who were not dependent on insulin had the highest risk of overall limb loss (p = 0.01). Patients undergoing delayed amputation required a significantly higher number (p = 0.01) of readmissions to the hospital for recurrent infection of the foot than those who did not undergo amputation. Data in the current study suggest that early major amputation in a subset of patients would prevent delay in the rehabilitation process of the amputee, decrease long term morbidity and reduce health care cost. An aggressive policy of early revascularization in patients with a pulse deficit may reduce the amputation rate in those with diabetes with severe infection of the foot.

Amputation, Surgical↗

PubMed1991

Venous disease.

Explore the source record for details and available documents.

Humans↗

PubMed1991

Surgery for chronic vein insufficiency.

1. Although varicose veins are the most prevalent form of venous insufficiency, obstruction or valvular incompetence of the deep system produces the most severe forms of lower extremity venous insufficiency and is responsible for most cases of leg ulceration of venous etiology. 2. With careful patient selection, surgery for varicose veins can be successful. Deep venous surgery, however, has limited indications and still carries a high failure rate; it should only be indicated in selected patients after conservative therapy has failed. 3. The main causes for failure of deep venous surgery are the low pressure and low velocity flow characteristics of the venous system that favor thrombosis.

Chronic Disease↗

PubMed1991

Intermittent claudication.

The natural history of intermittent claudication is generally benign. Clear indications for revascularization in patients with intermittent claudication are rest pain and necrotic tissue. Disabling claudication in patients who are at low operative risk is another acceptable indication for surgical treatment. Young patients with intermittent claudication from aortoiliac occlusion constitute a subset of patients in whom a more aggressive approach is justified. Nevertheless, in most patients, the management of intermittent claudication should be conservative.

Female↗

PubMed1990

Delayed diagnosis of a foreign body in the spinal canal.

The absence of neurologic deficit does not preclude the diagnosis of stab wound injury of the spinal cord. Adequate radiologic examination is fundamental in detecting retained foreign bodies. Surgical extraction of foreign bodies is indicated to avoid infection and myelopathy.

Adult↗

PubMed1988

Trachea-innominate artery fistula: retrospective comparison of treatment methods.

A fistula between the trachea and the innominate artery, a potentially fatal complication of tracheostomy, can be managed successfully. We have derived several guidelines from our experience with one such case and from a review of the 36 cases reported in the literature over the last decade. Diagnosis must be established before exsanguination occurs. Bronchoscopy and angiography are often nondiagnostic. Control of hemorrhage and a patent airway are the initial goals of treatment. Interruption of the innominate artery is the definitive treatment, with a low rebleeding rate (7%, 1/14 cases) and good long-term survival (64%, 9/14 cases). Maintenance of continuity of the innominate artery is contraindicated, because of a high rebleeding rate (60%, 6/10 cases) and poor long-term survival (10%, 1/10 cases). There is no convincing evidence that interruption of the innominate artery causes significant neurologic or vascular compromise.

Adult↗