Biomedical subjects

R D Kohl

Publications and source records attributed to R D Kohl.

At least 19 recordsLinked to original sources

PubMed2000

The utility of transesophageal echocardiography in determining the source of arterial embolization.

Arterial embolism is frequently of a cardiac source. Arterial-arterial and paradoxical embolization also occurs. Failure to identify the origin may subject the patient to an important series of events. Herein we describe seven cases in which transesophageal echocardiography (TEE) was uniquely valuable in identifying the source or mechanism and in which conventional echocardiography and aortography were nondiagnostic. We conducted a chart review of patients with arterial emboli definitively diagnosed after undergoing TEE. Seven patients (mean age 68 years) were included in the study. Peripheral embolization occurred in four patients, visceral embolization occurred in one, and two experienced cerebrovascular events. Five patients had transthoracic echocardiography and six had aortography; none of these identified the source of embolization. All were diagnosed by TEE. Mobile aortic thrombus was the primary source in three patients, paradoxical embolization occurred in two, and two others had a combination of findings. Two patients received operative management with one mortality, and five received nonoperative management. The source of arterial emboli remains obscure in some patients. TEE can be valuable in identifying sources or mechanisms of embolization when angiography and conventional echocardiography are negative.

Aged↗

PubMed1999

Percutaneous transluminal angioplasty of infrainguinal vessels.

In the last decade, percutaneous angioplasty (PTA) has been used with increasing frequency to treat infrainguinal atherosclerotic lesions. In hopes of better delineating the role of PTA, we undertook a retrospective analysis of infrainguinal PTA in one hospital over a 7-year period. The charts of all patients receiving infrainguinal PTA from 1989 to 1996 were reviewed. Demographics, site and type of lesion, and results of treatment were recorded. Survival curves were plotted using the Kaplan-Meier method following current Society of Vascular Surgery/International Society for Cardiovascular Surgery (SVS/ISCVS) guidelines. Differences in times to first failure were tested using the log rank method. Failures were documented by duplex ultrasound. All patients requiring repeat intervention underwent contrast angiography. In selected patients with stenotic lesions <3 cm, infrainguinal PTA may be an appropriate initial treatment modality. However, 5-year patency rates are significantly lower than those achieved by saphenous vein grafting. The efficacy of the procedure is markedly decreased when used to treat arterial stenoses >3 cm in length as well as occlusions, and surgical revascularization may be a more appropriate initial therapeutic procedure.

Angioplasty, Balloon↗

PubMed1998

Does dextran 40 improve the early patency of autogenous infrainguinal bypass grafts?

PURPOSE: We determined whether the administration of dextran 40 would increase the early (30-day) patency of autogenous infrainguinal bypass grafts. METHODS: During a 4-year period, 244 patients undergoing 273 autogenous infrainguinal bypass grafts were prospectively enrolled into and completed this study. Patients were randomized into two groups; one of the groups received a 72-hour infusion of dextran 40 after surgery, and the other did not. Comparisons were made between those patients who did and did not receive dextran 40 with respect to risks factors, demographics, and early graft patency. RESULTS: One hundred twenty-six procedures were accompanied by the use of dextran; 147 were not. There was no significant difference between the two groups with respect to patient age, gender, perioperative risk factors, indication for surgery, or location of bypass graft (popliteal vs tibial). Among those patients receiving dextran, there were eight early occlusions (6.4%) and four deaths (3.2%); 89.7% of the patients were alive with patent grafts 30 days after surgery. In the group not receiving dextran, there were 10 early occlusions (6.8%) and 3 deaths (2%); 90.5% of the patients were alive with patent grafts 30 days after surgery. There was no significant difference between the two groups with respect to rate of early occlusion (p = 1.00), death (p = 0.71), or 30-day patency (p = 0.84). CONCLUSIONS: The administration of dextran 40 does not increase the early patency of autogenous infrainguinal bypass grafts. Its routine use during these procedures cannot be recommended.

Adult↗

PubMed1996

Does the choice of material influence early morbidity in patients undergoing carotid patch angioplasty?

BACKGROUND: This study was undertaken to determine whether the choice of material influences the early morbidity of patients undergoing carotid patch angioplasty. METHODS: Before undergoing carotid endarterectomy, 190 patients were randomized to receive 207 patch closures with either Dacron (USCI Sauvage knitted velour) or saphenous vein harvested from the thigh. RESULTS: One hundred seven Dacron and 100 vein patch angioplasties were performed. No significant difference was seen between the two groups in patient age, sex preoperative risk factors, or indication for operation (p > 0.25 for each variable). Among the patients undergoing Dacron patch angioplasty three strokes (two temporary and one permanent), seven episodes of bleeding requiring reoperation, and two neck wound infections requiring rehospitalization occurred. The final 32 patients with Dacron patch closures had their anticoagulation reversed and had no bleeding complications. Complications inpatients undergoing vein patch closure included one fatal perioperative stroke, two episodes of bleeding requiring reoperation including one patch rupture, and three groin infections requiring hospitalization. No significant difference was seen between the two groups in the rate of perioperative stroke (p = 0.62), episodes of bleeding (p = 0.17), or infection (p = >0.67). CONCLUSIONS: Carotid patch angioplasty can be performed with an acceptably low complication rate with either Dacron or vein, and the choice of patch material does not clinically affect patient morbidity. However, reversal of anticoagulation is recommended to minimize bleeding complications in patients undergoing Dacron patch angioplasty.

Aged↗

PubMed1996

Selective use of the intensive care unit after nonaortic arterial surgery.

PURPOSE: The purpose of this study was to determine whether the institution of a clinical protocol combining 6 hours of recovery room observation and guidelines for intensive care unit (ICU) admission would allow selected patients to be safely transferred directly to a surgical floor after nonaortic arterial reconstruction. METHODS: After a clinical pathway was formed, 134 consecutive patients undergoing 154 nonaortic arterial operations were prospectively enrolled in this study. Patients requiring ICU care and the responsible factors were identified. Comparisons of risk factors and demographics were made between those patients who did and did not require ICU care. RESULTS: Twelve (7.8%) patients spent a total of 27 days in the ICU (range 1 to 11 days). As per our guidelines four patients were transferred to the ICU for invasive monitoring, and four were sent to the ICU because of refractory hemodynamic instability or arrhythmia in the postanesthetic recovery room. An additional four patients were transferred to the ICU after having been on the surgical floor for 24 to 72 hours because of the following perioperative complications: prolonged chest pain (one), pneumonia (one), heart failure (one), and graft occlusion requiring a urokinase infusion. Patients admitted to the ICU were more likely to have heart disease (p = 0.02) and to have had an operation other than carotid endarterectomy (p = 0.04) than those who were not. The 30-day mortality rate was 1.4%. CONCLUSIONS: The implementation of a clinical protocol similar to the one used in this study will allow many patients undergoing nonaortic vascular surgery to avoid the use of the ICU. This approach will conserve hospital and financial resources without adversely affecting patient morbidity and mortality rates.

Aged↗

PubMed1996

The treatment of hand ischemia by arterial ligation and upper extremity bypass after angioaccess surgery.

BACKGROUND: Hand ischemia remains an uncommon but potentially devastating complication of angioaccess operations. In the past, fistula ligation, arterial banding, and graft lengthening have been recommended as treatment with varying degrees of success. The procedure of arterial ligation and upper extremity bypass has recently been proposed as a more physiologic alternative method of treating this problem. STUDY DESIGN: The records of six patients with hand ischemia after hemodialysis access surgery who were treated with arterial ligation and revascularization were reviewed. Indications for operation, patient demographics, and risk factors were noted. The clinical results of surgery as well as fistula and bypass graft patency were recorded. RESULTS: All six patients demonstrated marked improvement in the perfusion of the affected hand. Five of six patients had complete resolution of their symptoms, while one continues to have a mild residual numbness of the hand. All fistulas and arterial bypass grafts remain patent at a follow-up period of two to 18 months (mean, 7.4 months). There were no perioperative complications or deaths. CONCLUSIONS: The technique of arterial ligation and upper extremity bypass provides a consistent and reliable method of correcting hand ischemia after angioaccess surgery. We believe it is the procedure that is most likely to alleviate the clinical symptoms of hand ischemia without jeopardizing the long-term function of the hemodialysis fistula.

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PubMed1995

Carotid endarterectomy with shortened hospital stay.

OBJECTIVE: To review the outcome of a consecutive series of patients undergoing carotid endarterectomy with a focus on length of stay. DESIGN: Retrospective case review. SETTING: Six hundred-bed community hospital. PATIENTS: During a 40-month period, we performed 266 carotid endarterectomies. Ages of patients ranged from 49 to 91 years (mean, 71.2 years). Seventy-two percent were hypertensive, 55% were smokers, 24% were diabetic, and 22% had symptomatic heart disease. Indications for operation included asymptomatic stenosis in 48% of patients, transient ischemia attack in 23%, stroke in 24%, and nonhemispheric symptoms in 5%. OUTCOME MEASURES: Perioperative complications and conditions precluding early hospital discharge were noted. In patients discharged within 48 hours of operation, problems requiring readmission within 30 days were recorded. RESULTS: Five patients (1.9%) experienced perioperative strokes, of which three were permanent and two temporary. There was one perioperative death. Hospital stays ranged from 1 to 9 days (mean 1.7 days). Sixty-three percent of the patients were discharged within 24 hours and 88% within 48 hours of operation. Patients staying in the hospital more than 48 hours were significantly older (P = .008). Other factors did not correlate with length of stay. Readmission was required in five patients. CONCLUSIONS: Patients having an uneventful course following carotid endarterectomy may be safely discharged within 48 hours of operation. Complications occurring after this time are infrequent and often unpredictable. It is unlikely that lengthening patient stay would decrease or eliminate these complications.

Age Factors↗

PubMed1995

The percutaneous treatment of angioaccess graft complications.

BACKGROUND: In the last decade, percutaneous techniques have been used with increasing frequency to treat angioaccess graft complications. The role of these procedures and their outcomes in patients on hemodialysis remains unclear. PATIENTS AND METHODS: The records of all patients receiving percutaneous treatment of failed or failing angioaccess grafts were reviewed. Patient demographics, site and type of percutaneous intervention, and results of treatment were recorded. Survival curves were plotted using the Kaplan-Meier method, and differences in times to first failure between types of intervention were tested using the log rank method. RESULTS: Grafts not requiring thrombolysis had significantly higher patency rates than those that did (P < 0.0001). Patency of grafts undergoing angioplasty of sites remote from the venous anastomosis were significantly higher than those of grafts undergoing venous anastomotic dilatation (P = 0.0004). CONCLUSIONS: Percutaneous techniques are most effective in treating failing but patent angioaccess grafts, especially those with stenoses remote from the venous anastomosis. The efficacy of percutaneous techniques diminishes significantly when used to treat grafts that have progressed to occlusion.

Adult↗

PubMed1994

Ruptured abdominal aortic aneurysms. A community experience.

OBJECTIVE: To determine the relative contribution of preoperative, operative, and postoperative factors to mortality in patients with ruptured abdominal aortic aneurysms. DESIGN: Retrospective case series. SETTING: Three primary care hospitals in a community setting. PATIENTS: Ninety-nine patients operated on for ruptured abdominal aortic aneurysms in the selected community between January 1984 and January 1992. OUTCOME MEASURES: Preoperative, operative, and postoperative factors were subjected to univariate and multivariate analysis to determine their relative contribution to patient mortality. Differences were considered significant at P = .05. RESULTS: The overall in-hospital mortality rate was 57%. The independent predictors of death were patient's age, surgical expertise, major intraoperative technical problems, hematocrit on admission, and units of red blood cells transfused during surgery (P < .05 for each). The operative mortality rate for individual surgeons ranged from 20% to 100%. Fifteen technical errors were identified, resulting in a 43% mortality rate. Surgeons with the highest mortality rates had the highest incidence of iatrogenic technical problems (P > .001). CONCLUSIONS: The outcome of patients with ruptured abdominal aortic aneurysms is, in part, determined by their preoperative status; however, surgical expertise and the avoidance of technical error significantly impact survival in patients with ruptured abdominal aortic aneurysms and should be a major focus of our attention.

Aged↗

PubMed1994

Iliac angioplasty as a prelude to distal arterial bypass.

BACKGROUND: Patients with limb ischemia and diffuse aortoiliac or combined aortoiliac and femoropopliteal disease present as a difficult problem for surgeons. This study was done to determine whether or not angioplasty can be successfully used as a prelude to distal bypass in patients with multilevel arterial occlusive disease. STUDY DESIGN: This is a retrospective review of an entire hospital experience with iliac angioplasty used as a prelude to distal arterial bypass. Kaplan-Meier life table analysis was performed and comparisons were made using log rank method. RESULTS: During a six year period, 37 patients underwent percutaneous iliac angioplasty before distal arterial reconstruction. Subsequent arterial reconstructions included femorofemoral bypass in nine patients, femoropopliteal bypass in 25 patients, femorotibial bypass in two patients, and common femoral endarterectomy in the remaining patient. The primary graft patency rate was 81 percent at five years. The overall success of iliac angioplasty was 76 percent at five years. Limb salvage was achieved in 78 percent of the patients with threatened extremities, and there was no perioperative mortality. CONCLUSIONS: Iliac angioplasty can successfully be used as a prelude to distal arterial bypass in patients with multilevel disease. The rate of angioplasty failure is low and grafts often remain patent in the face of early hemodynamic inflow failure, allowing salvage by operation or repeat dilatation. Close follow-up evaluation will allow early detection and appropriate correction of changes in inflow hemodynamics that occur before graft closure.

Aged↗

PubMed1994

Angiographic catheter induced arterial occlusion.

During a nine year period, the authors treated 37 patients with angiographic catheter induced arterial occlusions. Twenty-nine patients presented with acutely ischemic extremities requiring urgent intervention. Arterial thrombosis followed transfemoral cardiac catheterization or angioplasty in 13 patients, transbrachial catheterization in 13 and peripheral angiography or angioplasty in three. Primary arterial repair was sufficient to restore adequate distal perfusion in 23 patients; however, four required femorofemoral bypass and two required axillofemoral grafts to restore adequate distal perfusion. There were two perioperative deaths and no patient required amputation. Eight patients presented weeks to months after arterial injury. Two patients were minimally symptomatic and were treated without operation. Six patients had significant ischemic symptoms and required arterial bypass operation. All grafts have remained patent during a follow-up period ranging from 18 months to seven years (mean of 28 months). Appropriately planned and executed operative therapy is effective in preventing limb loss and functional impairment in patients with arterial thrombosis after angiographic procedures.

Adolescent↗

PubMed1993

Direct revascularization for the treatment of forearm and hand ischemia.

During an 8-year period, 65 patients underwent operation for ischemia of the arm and hand. Fifty-four patients presented with an acutely ischemic extremity. Twenty-two had cardiac origin emboli, 9 had arterial-arterial emboli, 8 had traumatic occlusion of the brachial artery, and 15 patients developed arterial insufficiency after iatrogenic intervention. Twenty-one of 22 patients with cardiac emboli were successfully treated with embolectomy alone. The majority of patients with arterial-arterial emboli and traumatic or iatrogenic injuries required arterial reconstruction in addition to clot retrieval. After operation, 53 of 54 patients were asymptomatic. Eleven patients underwent operation for chronic ischemia. Seven patients had axillo-brachial saphenous vein grafts, two had carotid-subclavian bypass grafts, and two patients underwent aorto-innominate bypass. All grafts remained patent during follow-up that ranged from 6 months to 8 years. We conclude that operative therapy is very effective in preventing limb loss and functional impairment in patients with acute or chronic upper extremity ischemia.

Adolescent↗

PubMed1992

Spontaneous peripheral arterial microembolization.

Over a seven year period 52 patients having a clinical diagnosis of spontaneous peripheral arterial microembolization were identified. Sixty-one percent of patients were female, 15% were diabetic, and 73% used tobacco chronically. A striking finding was the very high incidence of associated systemic disorders such as thrombocytosis (8), polycythemia vera (3), metastatic adenocarcinoma (3), or collagen disease requiring steroid therapy (4). Forty-nine patients had significant proximal arterial lesions as the origin of their emboli. Three patients had digital ischemia as a result of increased platelet aggregation without arterial obstruction. Forty-eight patients underwent surgical therapy. Operative mortality was 4% and overall limb salvage in survivors was 96%. The clinical syndrome of arterial microembolization may result from several pathophysiologic mechanisms including cholesterol embolization from ulcerated plaques, fibrino-platelet aggregation in patients with hematologic disorders, or dislodgement of mural thrombus in those with aneurysmal disease. We observed aortoiliac disease to be more frequent than femoral-popliteal disease, and both were amenable to surgical correction. We conclude that the genesis of arterial microembolization is multifactorial and that a variety of systemic diseases may work in concert with atherosclerotic arterial disease to produce this clinical syndrome. Prompt recognition and appropriate treatment of this disorder can yield high rates of limb salvage.

Aged↗

PubMed1992

Bilateral infrapopliteal artery aneurysms.

The authors report the case of a 37-year-old man with bilateral posterior tibial artery aneurysms and concomitant collagen vascular disease. The patient initially presented with pain and swelling of the calves. The diagnosis was made by duplex scan and confirmed with arteriography. Diagnostic studies later verified the presence of a lupus-like syndrome. To date, 10 patients with aneurysms of the infrapopliteal arteries have been reported in the literature; four of these have had associated systemic diseases. These reports are reviewed; their clinical manifestations are discussed, and a treatment plan for these uncommon lesions is presented.

Adult↗

PubMed1992

Salmonella infections of the abdominal aorta.

Salmonella accounts for up to one-third of all primary abdominal aortic infections. During the past ten years, we have treated three patients with this disease and have reviewed an additional 61 instances found in the English literature. The overall survival rate was 46 percent. Fever and back or abdominal pain were present in more than 90 percent of the patients, while a pulsatile mass was present in only 42 percent of those reported. Blood cultures were positive in 73 percent of patients. Computed tomography and angiography were helpful in delineating the presence of aneurysms and defining the extent. Twenty-two patients were treated without undergoing aortic resection; there were no survivors. One patient had an aortic resection without reconstruction and survived. Twenty-eight patients were treated with aortic resection and anatomic reconstruction. Six patients in this group died of graft sepsis and an additional six patients required graft removal for persistent infection. In contrast, 18 of 19 patients treated with extra-anatomic grafting and aneurysm resection survived, with only one death from aortic stump sepsis. No patient has required graft removal for sepsis. These results suggest that aneurysm resection and extra-anatomic bypass is the treatment of choice in patients with Salmonella infections involving the infrarenal aorta.

Aged↗

PubMed1990

Surgical procedures in the management of Takayasu's arteritis.

Takayasu's arteritis is an inflammatory arteriopathy that often progresses to obliteration of multiple large arteries. Variable results have been reported after medical and surgical management. Twenty female patients with Takayasu's arteritis were treated from 1973 to 1989. Eleven (55%) patients had hypertension. Upper or lower extremity ischemia was present in 12 (60%) patients and cerebrovascular insufficiency in seven (35%). Nine patients initially managed with corticosteroids had no improvement in signs or symptoms of arterial insufficiency. Eleven patients had 16 vascular procedures for the following indications: renovascular hypertension (6), extremity ischemia (5), cerebrovascular insufficiency (2), dilation ascending aorta with aortic insufficiency (1), thoracic aortic aneurysm (1), abdominal aortic aneurysm (1). Procedures included aortorenal bypass (5), carotid-subclavian, axillary, or brachial bypass (4), aorto-carotid bypass (2), aneurysm resection (2), supra-celiac aorto-femoral bypass (1), ascending aorta/aortic valve replacement (1), and nephrectomy (1). Clinical improvement occurred in all patients. There were no operative deaths. All are alive at a mean follow-up of 5.75 years (6 months to 16 years). Revision of the initial reconstruction has been required for recurrent renovascular hypertension in one patient and extremity ischemia in another. The other nine patients remain symptomatically improved. Symptomatic Takayasu's arteritis frequently requires arterial reconstruction. Symptomatic improvement and excellent long-term graft patency can be expected after arterial reconstruction.

Adolescent↗

PubMed1987

Mycotic suprarenal aortic aneurysm.

Two cases of mycotic suprarenal aortic aneurysm treated by anatomic reconstruction are presented. Diagnosis was facilitated by 67-Gallium Citrate Scanning, Computer Assisted Tomography (CT), and Angiography. Increasing symptoms with attenuation of the aortic wall identified by CT necessitated urgent resection and reconstruction in both patients. Contained rupture of the aneurysm was found in one patient. Cultures of the resected tissue grew Salmonella dublin and Bacteroides fragilis. The patients were treated with continuous antibiotic therapy. Follow-up demonstrated asymptomatic patients with sterile blood cultured and good anatomic results on CT at one year. No recurrent sepsis nor aneurysmal dilatation is evident to date. Based on our experience and the available literature we conclude that inline reconstruction is the method of choice for treatment on these lesions.

Aged↗

PubMed1976

Vascular manifestations of the thoracic outlet syndrome. A surgical urgency.

Although the vascular manifestations of the thoracic outlet syndrome are infrequent, their presence is an ominous portent for the affected limb. The cases of two recent patients indicate the importance of prompt recognition, urgent angiography, and definitive surgery. Regarding the surgical procedure, we used a two-incision approach-supraclavicular and intraclavicular-combining scalenotomy, resections of the cervical rib if present, the first thoracic rib, and the subclavian artery with retroclavicular interposition woven Dacron graft reconstruction. Preceding graft replacement, a Fogarty catheter thrombectomy of the distal brachial artery tree is done with completion arteriography to ensure freedom from retained distal thrombus. First rib resection is easily performed; subsequent vascular repair is also carried out, using this approach. We did not add sympathectomy to these cases, believing that early recognition and treatment will obviate its necessity. Follow-up has supported the efficacy of the treatment plan as presented.

Adult↗