Biomedical subjects

J F McKinsey

Publications and source records attributed to J F McKinsey.

5 recordsLinked to original sources

PubMed1996

Mechanisms of neurologic deficits and mortality with carotid endarterectomy.

OBJECTIVE: To evaluate the incidence and etiology of perioperative complications of carotid endarterectomy. DESIGN: Retrospective review of carotid endarterectomies performed over 13 years. Risk factors, indications, results of electroencephalographic (EEG) monitoring, and outcomes were evaluated. SETTING: University medical center. PATIENTS: Three hundred sixty-seven consecutive primary carotid endarterectomies were performed on 336 patients. Indications for operation included transient ischemic attack (48.5%), asymptomatic stenosis (24%), stroke (17%), nonlateralizing ischemia (9.5%), and stroke-in-evolution (1%). MAIN OUTCOME MEASURES: Postoperative neurologic deficits (permanent and transient) and deaths were correlated with preoperative symptoms, probable mechanism of the neurologic event, intraoperative EEG changes, and the use of intraoperative shunts. RESULTS: Four new permanent neurologic deficits (1.1%) and one transient postoperative deficit were noted. Of the five deficits, three were related to undiagnosed intraoperative cerebral ischemia and two were related to perioperative emboli. Three perioperative deaths (0.8%) occurred: two of myocardial infarction and one of an intracerebral hemorrhage from a ruptured arteriovenous malformation. Intraoperative EEG tracings for the most recent consecutive 175 procedures were analyzed. Shunts were used in 45 patients (26%), 38 of whom demonstrated significant EEG changes with carotid clamping. CONCLUSIONS: Carotid endarterectomy can be performed with a low risk of stroke (1.1%) and death (0.8%). Stroke was due to cerebral ischemia or embolization. With meticulous surgical technique, death is due to myocardial ischemia and not neurologic events.

Adult↗

PubMed1995

Extra-anatomic reconstruction.

Extra-anatomic bypass grafts have proven to be effective in bypassing infected regions, in avoiding hostile abdomens, and in patients with limited life expectancy. The extra-anatomic bypass graft can be used as a temporizing conduit while infected fields are definitively treated. The recommendation to expand the role of extra-anatomic bypass grafts over more direct revascularization with an aortobifemoral artery bypass graft must be critically evaluated. With advances in anesthesia and critical care management, the postoperative mortality for aortobifemoral bypass is 3% to 5%, with an incidence of myocardial infarction of 2%. Long-term primary patency of the aortofemoral bypass graft is 80% to 92% at 5 years. The 5-year primary patency rate for the axillofemoral bypass graft of 50% to 73% does not strongly support the expanded role of extra-anatomic bypass in otherwise healthy patients undergoing aortoiliac bypass. Yet the extra-anatomic bypasses have a vital role in the management of selected patients and should be in the armamentarium of all vascular surgeons.

Arterial Occlusive Diseases↗

PubMed1994

Premedication with oral and transdermal clonidine provides safe and efficacious postoperative sympatholysis.

We studied 61 patients undergoing elective major non-cardiac surgery in a randomized, double-blind, placebo-control clinical trial to test the hypothesis that the addition of clonidine to a standardized general anesthetic could safely provide postoperative sympatholysis for patients with known or suspected coronary artery disease. Patients were allocated randomly to receive either placebo (n = 31) or clonidine (n = 30). The treatment group received premedication with a transdermal clonidine system (0.2 mg/d) the night prior to surgery, which was left in place for 72 h, and 0.3 mg oral clonidine 60-90 min before surgery. Clonidine reduced enflurane requirements, intraoperative tachycardia, and myocardial ischemia (1/28 clonidine patients vs 5/24 placebo, P = 0.05). However, clonidine decreased heart rates only during the first five postoperative hours; the incidence of postoperative myocardial ischemia (6/28 clonidine vs 5/26 placebo) did not differ between the two groups. Patients who experienced postoperative myocardial ischemia tended to have higher heart rates after surgery. Clonidine significantly reduced the plasma levels of epinephrine (P = 0.009) and norepinephrine (P = 0.026) measured on the first postoperative morning. There were no differences in the need for intravenous fluid therapy or antihypertensive therapy after surgery. The number of hours spent in an intensive care setting and the number of days spent in hospital were not different between the two groups. These results suggest that larger doses of clonidine should be investigated for their ability to decrease postoperative tachycardia and myocardial ischemia.

Administration, Cutaneous↗

PubMed1994

Use of the Greenfield filter in patients with major trauma.

Patients with major trauma often cannot be given the benefit of preventive measures such as pneumatic compression boots and low-dose heparin against pulmonary embolism. The Greenfield filter is accepted as a safe and effective method of prophylaxis of this complication. The aim of this study was to evaluate the efficacy of placement of the Greenfield filter in 161 patients with major trauma. Between January 1984 and July 1988, 94 patients with an injury severity score (ISS) of > 16 were treated. This score is predictive of a mortality rate of at least 10% and defines major trauma based on anatomic injury. Some 20% (19 of 94) of these patients developed deep vein thrombosis despite standard prophylactic measures and 8% (eight of 94) suffered pulmonary embolism, two of which were fatal. Pulmonary embolism occurred without antecedent evidence of deep vein thrombosis in another 15% of patients (14 of 94), three of which caused death. From August 1988 until July 1992, of 67 other patients with an ISS > 16, 13% (nine of 67) developed deep vein thrombosis and 1% (one of 67) had a pulmonary embolism; this was not statistically significant (P > 0.25). Of these 67 patients who were considered to be at high risk of pulmonary embolism, because of a contraindication to anticoagulation or physical impediment to sequential compression boots, 29 had prophylactic placement of a Greenfield filter. No pulmonary emboli occurred in these patients. During long-term follow-up (mean 32.8 (range 4-58) months), 84% of the surviving patients (21 of 25) underwent duplex ultrasonography of the inferior vena cava; patency of the vessel was confirmed in all patients.

Adolescent↗

PubMed1990

Carotid patch angioplasty: immediate and long-term results.

To determine the benefit of carotid patch angioplasty, a retrospective study of 1000 consecutive carotid endarterectomies was done. Based on the type of carotid endarterectomy closure, patients were divided into four groups: 250 had primary closure, 250 had expanded polytetrafluoroethylene patch, 250 had Dacron patch, and 250 had saphenous vein patch. On the basis of operative technique or type of carotid artery closure, no statistical difference was found in the incidence of postoperative stroke (p greater than 0.25): primary closure 1.6% (4), expanded polytetrafluoroethylene 2.0% (5), Dacron patch 1.6% (4), and saphenous vein patch (0). Postoperative carotid patency was determined by B-mode ultrasonography, and 717 patients were evaluated in follow-up extending to 6 years (mean 37.8 months). Based on the method of carotid endarterectomy closure, no significant difference (p greater than 0.25) was found in the incidence of significant restenosis (greater than 50% diameter reduction): primary closure 4.0% (7), expanded polytetrafluoroethylene 4.0% (6), Dacron 5.4% (9), and saphenous vein 1.0% (2). Significant restenosis was most frequent in habitual smokers (93%, 25/28) and females (78%, 22/28) despite the method of carotid endarterectomy closure. No statistical difference was found in the incidence of late ipsilateral stroke either (p greater than 0.25): primary closure 2.9% (5), expanded polytetrafluoroethylene 2% (3), Dacron 5% (3), and saphenous vein 0%. These results indicate that the incidence of postoperative stroke, regardless of method of arterial closure, was not statistically different. The method of carotid closure did not appear to affect the occurrence of late ipsilateral stroke or restenosis; however, patch angioplasty with saphenous vein appears appropriate in habitual smokers, and likely in patients with small internal carotid arteries.

Blood Vessel Prosthesis↗