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B A Perler

Publications and source records attributed to B A Perler.

At least 37 records · Page 2Linked to original sources
PubMed1996

The impact of advanced age on the results of carotid endarterectomy: an outcome analysis.

BACKGROUND: This study examined whether advanced age adversely influences the outcome of carotid endarterectomy. STUDY DESIGN: The records of 173 patients who underwent 187 carotid endarterectomies performed by the author from January 1990 through December 1995 were retrospectively reviewed. Group 1 included 58 patients, ranging in age from 75 to 92 years (mean, 79.4 years), who underwent 63 procedures, and group 2 included 115 patients, ranging in age from 41 to 74 years (mean, 66.3 years), who underwent 124 procedures. The operation was performed for symptomatic disease in 67 percent of the cases in each group. The operated lesion was more than 80 percent stenotic in 85 percent of the group 1 and 79 percent of the group 2 cases. RESULTS: No significant differences were found in the operative mortality (1.6 percent compared with 1.6 percent), incidence of perioperative stroke (4.8 percent compared with 1.6 percent), or rate of major cardiac complications (7.9 percent compared with 7.3 percent) between groups 1 and 2. No significant difference was found in the mean postoperative length of hospital stay between the group 1 and group 2 patients (4.13 +/- 2.58 days compared with 3.68 +/- 1.40 days). However, during the last 2 years of the study, the mean postoperative length of stay among the group 2 patients (3.06 +/- 1.44 days) was significantly shorter than among the group 1 patients (4.15 +/- 1.45 days) (p < .05). CONCLUSIONS: Advanced age does not adversely affect the results of carotid endarterectomy. However, the very elderly may be expected to experience a longer postoperative length of stay because of associated comorbid conditions.

Adult↗
PubMed1995

Carotid Dacron patch angioplasty: immediate and long-term results of a prospective series.

The purpose of the present study was to determine the acute clinical results associated with the performance of Dacron patch angioplasty during carotid endarterectomy, and to define the incidence of residual and recurrent carotid stenoses in patched arteries. Some 115 consecutive patients (mean age 68.0 years) underwent 119 primary carotid endarterectomy procedures in which the arteriotomy was repaired with a Dacron patch. The patients underwent duplex/occulopneumoplethysmography evaluation at 6 months after surgery, and annually thereafter. There was one (0.8%) operative death and two (1.7%) perioperative strokes. There were no immediate postoperative carotid thromboses. There were no wound or patch infections acutely, or in long-term follow-up. Thirteen patients (11%) were lost to follow-up; hence 106 arteries in 102 patients were followed for 1-65 (mean 17.8) months, including 66 arteries (62%) that have undergone serial OPG/duplex evaluation. The incidence of residual stenoses (within 3 months) was 4.5%, and that of recurrent stenoses 4.8%. The results of the study show Dacron carotid patch angioplasty to be associated with excellent clinical results, with a relatively low incidence of residual/recurrent carotid stenoses.

Aged↗
PubMed1995

Catecholamine and cortisol responses to lower extremity revascularization: correlation with outcome variables. Perioperative Ischemia Randomized Anesthesia Trial Study Group.

OBJECTIVE: To determine whether catecholamine and cortisol secretory responses to surgery contribute to postoperative complications. DESIGN: Prospective, randomized, case series. SETTING: A university hospital operating suite and surgical intensive care unit. PATIENTS: Sixty patients undergoing lower extremity vascular surgery. INTERVENTIONS: Patients were randomized to receive either epidural anesthesia/epidural opiate analgesia (regional anesthesia) or general anesthesia/intravenous patient-controlled analgesia (general anesthesia). MEASUREMENTS AND MAIN RESULTS: Anesthesia was managed according to a prospectively designed protocol. Hemodynamic parameters and plasma catecholamine concentrations were determined at specific intraoperative and postoperative time points. Intraoperative and postoperative urine samples were collected and analyzed for free cortisol concentrations. Outcomes evaluated were cardiac (nonfatal myocardial infarction and cardiac death) and surgical (graft occlusion). Mean arterial pressure during emergence from anesthesia and in the early postoperative period correlated positively with plasma norepinephrine concentration (p < .01). In addition, plasma catecholamine concentrations were higher in patients with postoperative hypertension. Plasma norepinephrine concentrations at the time of emergence from anesthesia and postoperatively were also higher in patients requiring repeat surgery for graft revision, thrombectomy, or amputation (p < .05). Multivariate analysis indicated that the norepinephrine concentration at the time of emergence, but not type of anesthesia, correlated with reoperation for graft occlusion, suggesting that the previously reported beneficial effect of regional anesthesia may be due to modulation of the stress response. Myocardial infarction or cardiac death occurred in three patients. These patients had markedly increased catecholamine concentrations. CONCLUSIONS: The catecholamine response to lower extremity vascular surgery contributes to the development of postoperative hypertension and may also be important in the development of thrombotic complications.

Adult↗
PubMed1995

Hypercoagulability and the hypercoagulability syndromes.

Hypercoagulability is a state in which an alteration of the blood shifts the hemostatic balance toward excessive platelet/fibrin deposition leading to arterial and/or venous thrombosis [1]. Although the concept of hypercoagulability has been recognized clinically for more than a century, in recent years a number of specific disorders have been define, diagnostic tests developed, and treatment regimens improved. The currently recognized disorders are generally classified as primary or secondary states, although some of the primary conditions may develop as a result of other disorders (Table 1). The primary disorders generally result from abnormalities of proteins in the coagulation or fibrinolytic systems. Although the number of secondary conditions is much greater, generally these syndromes are not as precisely defined on a molecular basis. Secondary hypercoagulability syndromes are subclassified into abnormalities of platelets, coagulation and fibrinolysis, and blood vessels and rheology (Table 1). While the prevalence and clinical significance of hypercoagulability are becoming increasingly apparent to physicians in general, this pathologic state is an especially practical concern to vascular interventionalists, as hypercoagulability is an important cause of early thrombosis after otherwise uncomplicated arterial interventional procedures. The purpose of this review is to describe the clinical presentation, diagnosis, and treatment of the hypercoagulability syndromes most likely to be encountered by the interventional radiologist.

Animals↗
PubMed1995

The influence of anesthetic method on infrainguinal bypass graft patency: a closer look.

Although several studies have demonstrated a reduced incidence of postoperative deep venous thrombosis among patients who receive regional anesthesia, the influence of anesthetic method on early arterial bypass graft patency has not been well studied. The records of 78 consecutive patients undergoing elective femoro-popliteal (FP) or femoro-tibial (FT) bypass grafts, and who were randomized to receive general anesthesia and postoperative patient-controlled intravenous narcotic analgesia (GEN, n = 41), or epidural anesthesia and postoperative continuous epidural analgesia (EPI, n = 37), were retrospectively reviewed. The two groups were evenly matched with respect to demographic characteristics, risk factors, and vascular variables. There was one death in each group, yielding an operative mortality of 2.6 per cent, and leaving 76 patients available for further analysis. Graft occlusion occurred in 11 (14.5%) cases within the first 7 postoperative days, including 9 (22.5%) GEN and 2 (5.6%) EPI patients (P < 0.05). There were two (4.4%) FP occlusions, including two (8.7%) GEN and 0(0%) EPI cases; there were nine FT occlusions, including seven (41.2%) GEN and two (14.3%) EPI cases. Graft occlusion occurred in 11 (17.1%) of the 64 limb salvage cases, including nine (27.3%) GEN and two (6.5%) EPI cases (P < 0.05), and in seven (12.7%) of 55 greater saphenous vein grafts, including six (22.2%) GEN and 1 (3.6%) EPI cases (P < 0.05). By multivariate analysis, FT grafts, preoperative plasminogen activator inhibitor-1 (PAI-1) levels, and GEN were predictive of early graft occlusion (P < 0.05). Furthermore, the levels of circulating PAI-1 were higher 24 hours postoperatively among patients in the GEN group (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Carotid endarterectomy--is intensive care unit care necessary?

PURPOSE: The purpose of this study was to determine whether postoperative intensive care unit care is necessary for all patients undergoing carotid endarterectomy and whether a subgroup of patients at low-risk not requiring treatment in the intensive care unit could be identified. METHODS: Case control analysis of random numbers sample over the last decade of 50% of patients undergoing isolated carotid endarterectomy at a tertiary care hospital. One hundred twenty-nine patients undergoing carotid endarterectomy were identified. Preoperative risk factors, intraoperative course, intensive case unit interventions including vasoactive agents, myocardial ischemia/infarction, arrhythmias, bronchospasm, reintubation, neurologic events, and need for reoperation, were recorded. Timing of interventions, length of stay in intensive care unit, and postoperative course were all recorded. Financial impact was assessed. RESULTS: Among 129 patients only 31 patients did not require intensive care unit interventions. A multivariate linear regression analysis demonstrated a model in which a preoperative history of hypertension, myocardial infarction, arrhythmia, and chronic renal failure were 83% predictive of the need for an intensive care unit bed. Specifically, patients could be stratified into a low-risk group before the operation by less than four risk factors. Additionally, all patients requiring interventions or with adverse outcomes were identified by the eight postoperative hour. CONCLUSIONS: In preoperative scheduling of intensive care unit beds, patients with less than four risk factors can be stratified to monitoring beds and those with greater than or equal to four can be stratified to intervention beds. After 8 hours, if no interventions are necessary or adverse outcomes occur, then floor recovery is safe. Patients who satisfy this algorithm would save 50% of current intensive care unit charges.

Adult↗
PubMed1994

Vascular disease in the elderly patient.

At a time of potentially dramatic changes in health care policy in this country, and in view of the necessity for health care cost containment, physicians are expected to exercise serious introspection in the selection of treatment for the elderly patient with peripheral arterial disease. These decisions should be made while acknowledging that it is the goal of the health-care provider "to postpone chronic illness, to maintain vigor, and to slow social and psychological involution." For the elderly patient with an abdominal aortic aneurysm, with significant carotid disease, or with limb-threatening peripheral ischemia, the evidence is compelling that timely surgical intervention in properly selected patients is well tolerated and will satisfy this goal.

Aged↗
PubMed1994

Visceral lipid peroxidation occurs at reperfusion after supraceliac aortic cross-clamping.

PURPOSE: Recently, we have reported that lipid peroxidation specific to oxygen free radical-mediated injury increased immediately after reperfusion of human liver allografts. However, in the human liver transplantation setting it was impossible to disassociate the contributions to lipid peroxidation caused by the warm and cold ischemic phases from those caused by reperfusion. Therefore we now have studied lipid peroxidation at reperfusion after supraceliac aortic cross-clamping in patients with normal livers. METHODS: Ethane, a noninvasive biomaker of lipid peroxidation, was measured in exhaled breath of patients before and during cross-clamping of the thoracic aorta and at sequential time intervals after visceral reperfusion. RESULTS: Approximately a two-fold transient increase in the ethane level was observed at around 15 minutes after reperfusion in those patients whose aortas were cross-clamped for more than 18 minutes. CONCLUSIONS: These results indicate that free radical-mediated lipid peroxidation occurs at reperfusion of warm ischemic viscera in the clinical setting of aortic repair. This observation supports the hypothesis that substantial lipid peroxidation occurs when tissues are subjected to cold or warm ischemia followed by reperfusion.

Aged↗
PubMed1994

Carotid endarterectomy in the very elderly: is it worthwhile?

BACKGROUND: Stroke continues to be the third leading cause of death in this country, its incidence and corresponding mortality rate increase with age, and in the majority of cases it results from arteriosclerosis of the carotid artery. Although recent studies have clearly shown the benefit of carotid endarterectomy in reducing the incidence of stroke, performance of this procedure in very elderly patients, the patient population for whom it should be most beneficial, has been challenged by some investigators on the basis of perceived increased operative risk. METHODS: The records of all carotid endarterectomies (n = 63) performed during the last 12 years for all patients (n = 59) with a minimum age of 75 years were reviewed to define the short-term risk of operative mortality, stroke and other major complications, and the long-term outcome. RESULTS: No (0%) operative deaths and three (4.8%) perioperative strokes occurred. Major cardiac complications occurred in five cases (7.9%). Follow-up, ranging from 1 to 122 months (mean, 27.4 months), was available for 54 patients (91.5%). Cumulative freedom from stroke was 92% at 2 years and 80% at 5 and 10 years of follow-up. Long-term survival rate was 80% at 5 years and 52% at 10 years, and stroke-free survival rate was 68% at 5 years and 42% at 10 years of follow-up. CONCLUSIONS: Carotid endarterectomy can be performed in very elderly patients with low operative risk and excellent long-term results.

Aged↗
PubMed1993

Unintentional hypothermia is associated with postoperative myocardial ischemia. The Perioperative Ischemia Randomized Anesthesia Trial Study Group.

BACKGROUND: Hypothermia occurs commonly during surgery and can be associated with increased metabolic demands during rewarming in the postoperative period. Although cardiac complications remain the leading cause of morbidity after anesthesia and surgery, the relationship between unintentional hypothermia and myocardial ischemia during the perioperative period has not been studied. METHODS: One hundred patients undergoing lower extremity vascular reconstruction received continuous Holter monitoring throughout the first 24 h postoperatively. Myocardial ischemia was determined by a cardiologist masked to clinical variables. The patient's sublingual temperature on arrival at the intensive care unit immediately after the surgical procedure was used to divide the patients into two groups: hypothermic (temperature, < 35 degrees C; n = 33) and normothermic (temperature, > or = 35 degrees C; n = 67). The relationship between intentional hypothermia and myocardial ischemia occurring during the first postoperative day was evaluated by univariate and multivariate analyses. RESULTS: A greater percentage of patients had electrocardiographic changes consistent with myocardial ischemia in the hypothermic group (36%, 12 of 33) compared with those in the normothermic group (13%, 9 of 67, P = 0.008). Preoperative risk factors for perioperative cardiac morbidity were similar between the two groups, except for patient age. The mean age was 70 +/- 2 yr and 62 +/- 1 yr in the hypothermic and normothermic groups, respectively (P = 0.001). When subgroup and multivariate analyses were used to adjust for differences in age, temperature remained an independent predictor of ischemia (odds ratio, 1.82 per degree Celsius; 95% confidence interval, 1.09-3.02). The incidence of postoperative angina was greater in the hypothermic group (18%, 6 of 33) than in the normothermic group (1.5%, 1 of 67, P = 0.002). The incidence of PaO2 < 80 mmHg in the arterial blood was greater in the hypothermic group (52%, 17 of 33) than in the normothermic group (30%, 20 of 67, P = 0.03). CONCLUSIONS: Unintentional hypothermia is associated with myocardial ischemia, angina, and PaO2 < 80 mmHg during the early postoperative period in patients undergoing lower extremity vascular surgery.

Adult↗
PubMed1993

Perioperative morbidity in patients randomized to epidural or general anesthesia for lower extremity vascular surgery. Perioperative Ischemia Randomized Anesthesia Trial Study Group.

BACKGROUND: Perioperative morbidity may be modifiable in high risk patients by the anesthesiologist's choice of either regional or general anesthesia. This clinical trial compared outcomes between epidural (EA) and general (GA) anesthesia/analgesia regimens in a group of patients at high risk for cardiac and other morbidity who were undergoing similarly stressful surgical procedures. METHODS: One hundred patients scheduled for elective vascular reconstruction of the lower extremities were randomized to receive either EA for surgery followed by epidural analgesia, or GA for surgery followed by intravenous patient-controlled analgesia. Hemodynamic monitoring, blood pressure, and heart rate limits were determined prior to randomization. Management of anesthesia in the immediate postoperative period was standardized. The data collected included continuous electrocardiographic monitoring from the day before surgery through the third postoperative day, serial electrocardiograms, and cardiac enzymes. Cardiac ischemia, myocardial infarction, unstable angina, and cardiac death were identified by a cardiologist blinded to the type of anesthesia received. Other major morbidity was determined at the time of hospital discharge and at 1 and 6 months after surgery. RESULTS: Eleven patients who received GA required regrafting or an embolectomy during their hospital stay, compared with two patients who received EA. This association of GA with reoperation remained significant after adjustment for baseline differences. Cardiac outcomes were similar in the two groups with respect to perioperative death (1 EA and 1 GA), death within 6 months (4 EA and 3 GA), nonfatal myocardial infarction within 7 days (2 EA and 2 GA), unstable angina (0 EA and 2 GA), and myocardial ischemia following randomization (17 EA and 23 GA). Rates of major infections in the two groups (1 EA and 2 GA), renal failure (3 EA and 3 GA), and pulmonary complications (3 EA and 7 GA) also were similar. CONCLUSIONS: Carefully conducted epidural and general anesthesia appear to be associated with comparable rates of cardiac and most other morbidity in patients undergoing lower extremity vascular surgery. However, compared with general anesthesia, epidural anesthesia is associated with a lower incidence of reoperation for inadequate tissue perfusion and, therefore, may be advantageous for this surgical population.

Aged↗
PubMed1993

The effects of different anesthetic regimens on fibrinolysis and the development of postoperative arterial thrombosis. Perioperative Ischemia Randomized Anesthesia Trial Study Group.

BACKGROUND: The purpose of this clinical trial was to compare the effects of different anesthetic and analgesic regimens on hemostatic function and postoperative arterial thrombotic complications. METHODS: Ninety-five patients scheduled for elective lower extremity vascular reconstruction were randomized to receive either epidural anesthesia followed by epidural fentanyl (RA) or general anesthesia followed by intravenous morphine (GA). Intraoperative and postoperative care were controlled by protocol using predetermined limits for heart rate, blood pressure, and other monitoring criteria. Data collection included serial physical examinations, electrocardiograms, and cardiac isoenzymes to detect arterial thrombosis (defined as unstable angina, myocardial infarction, or vascular graft occlusion requiring reoperation). Fibrinogen, plasminogen activator inhibitor-1 (PAI-1), and D-dimer levels were measured preoperatively and at 24 and 72 h postoperatively. RESULTS: Preoperative fibrinogen levels were similar in both groups, remained unchanged after 24 h, and increased equally (45%) in the first 72 h postoperatively. PAI-1 levels in the GA group increased from 13.6 +/- 2.1 activity units (AU)/ml to 20.2 +/- 2.6 AU/ml at 24 h and returned to baseline at 72 h. In contrast, PAI-1 levels in the RA group remained unchanged over time. Twenty-two of 95 patients (23%) had postoperative arterial thrombosis, 17 of whom had received GA and 5 of whom, RA. Preoperative PAI-1 levels were higher in patients who developed postoperative arterial thrombosis (20.5 +/- 3.6 AU/ml vs. 11.2 +/- 1.4 AU/ml). Multiple logistic regression analysis indicated that GA and preoperative PAI-1 levels were predictive of postoperative arterial thrombotic complications. CONCLUSIONS: Impaired fibrinolysis may be related causally to postoperative arterial thrombosis. Because RA combined with epidural fentanyl analgesia appears to prevent postoperative inhibition of fibrinolysis, this form of perioperative management may decrease the risk of arterial thrombotic complications in patients undergoing lower extremity revascularization.

Aged↗
PubMed1993

Angioplasty, bypass surgery, and amputation for lower extremity peripheral arterial disease in Maryland: a closer look.

Tunis and colleagues attempted to assess the effect of peripheral angioplasty in a large population with descriptive epidemiologic methods. Their study suffered from a vague statement of purpose, inappropriate and inadequate outcome measures, undetermined differences in prevalence of peripheral vascular disease and prevalence of risk factors for bypass/amputation in 1989 versus 1979, no differentiation between levels of amputation or between primary and secondary amputation, lack of a unique ICD-9-CM code indicating angioplasty for peripheral vascular disease of the lower extremities, lack of unique patient identifiers, a mistaken perception of the adoption of angioplasty as "widespread" in Maryland, and the assumption of uniform coding accuracy throughout the period of study. We conclude that the study design of Tunis et al was inadequate to determine the beneficial effects of angioplasty or bypass surgery in the treatment of peripheral vascular disease. Moreover, the conclusion by Coffman (2) that "invasive procedures are indicated only for the severely ischemic limb" is completely unsupported by the study data. Physicians should not attempt to apply the results of the study by Tunis et al to individual case situations. It should be further appreciated that the study findings do not provide an adequate basis for policy-making decisions. It is clear that important clinical questions concerning the roles of angioplasty, bypass, and amputation should be answered with more definitive studies.

Algorithms↗
PubMed1993

Preoperative spinal artery localization and its relationship to postoperative neurologic complications.

PURPOSE: To evaluate the risk of spinal cord revascularization and ascertain the relationship between preoperative spinal arteriography and the frequency of postoperative neurologic injury and overall morbidity and mortality in patients who require surgical repair of thoracoabdominal aortic aneurysms. MATERIALS AND METHODS: Fifty patients scheduled for surgical repair of a thoracoabdominal aortic aneurysm underwent spinal arteriography. All patients were divided into a positive spinal artery group (in which the spinal artery was identified) or negative spinal artery group (in which the spinal artery was not identified) and further divided based on extent of disease. RESULTS: The complication rate of spinal arteriography was 4.6%; no patient had a permanent neurologic injury. No significant difference existed between the positive and negative spinal artery groups in occurrence of neurologic injury (P = .88) or combined morbidity and mortality (P = 51). CONCLUSION: Patients who require spinal cord revascularization do not have greater frequency of neurologic injury or overall morbidity and mortality than those without this requirement. Spinal arteriography enables definitive spinal cord revascularization and thereby reduces the risk of neurologic injury.

Adult↗
PubMed1993

Surgical treatment of femoral pseudoaneurysm following cardiac catheterization.

Over a period of 8 years, 31 femoral pseudoaneurysms following cardiac catheterization were surgically repaired in 15 men and 15 women ranging in age from 38 to 89 (mean 68.1) years. The catheterizations were performed for evaluation of coronary artery disease in 23 patients (77%), valvular heart disease in three (10%), both coronary artery disease and valvular disease in two (7%) and for other reasons in two (7%). Percutaneous transluminal coronary angioplasty was performed in eight patients (27%) and aortic valvuloplasty in one (3%). Surgical repair was performed from 1 to 47 (mean 10.2) days after catheterization under local anesthesia in 16 patients (52%), regional anesthesia in ten (32%) and general anesthesia in five (16%). All lesions were repaired by primary suture. The operating time ranged from 25 to 90 (mean 50.5) min and intraoperative blood loss from 50 to 900 (mean 259.2) ml. There were no operative deaths and one postoperative myocardial infarction. No patients have developed recurrent pseudoaneurysm, with follow-up ranging from 1 to 53 (mean 11.4) months. These results demonstrate that the surgical repair of femoral pseudoaneurysm following cardiac catheterization is safe, effective and durable.

Adult↗
PubMed1993

Rotational muscle flaps to treat localized prosthetic graft infection: long-term follow-up.

PURPOSE: The conventional management of prosthetic graft infection (PGI), including graft excision and extraanatomic revascularization, continues to be associated with substantial morbidity. Rotational muscle flap (RMF) closure of the infected wound, with preservation of the graft, is an alternative, albeit controversial, approach. METHODS: Over the last 7 years, 22 RMF procedures have been performed to close 19 wounds in 18 patients, ranging in age from 39 to 79 (mean 63.7) years, with PGI. Twenty-one grafts constructed of Dacron (13) or polytetrafluoroethylene (8) were covered in the groin (16), neck (2), or chest (1). The clinical presentations included abscess or purulent drainage in 14 grafts, hemorrhage in three, and infected false aneurysm in two wounds; positive bacterial culture results were obtained in each case. RESULTS: There was one (5.6%) operative death. Healing was achieved in the 18 wounds of the 17 operative survivors. No patients have been lost to follow-up. Three (17.6%) of these 17 patients had recurrent infection, including one patient who underwent a secondary RMF procedure with graft salvage, one who underwent excision of an occluded graft, and one who underwent excision and extraanatomic bypass and died. Four other patients died 1 to 6 (mean 3) months after RMF closure with healed wounds. Eleven (92%) of the 12 survivors have healed wounds and intact grafts with follow-up ranging from 8 to 83 (mean 39) months. For the entire series 15 (88%) of these 17 patients had healed wounds and intact grafts, with a mean follow-up of 30 months. CONCLUSIONS: These results suggest that RMF procedures are well tolerated and can achieve acceptable long-term graft salvage in selected patients with PGI.

Adult↗