Cerebral hemodynamics in patients with carotid artery occlusion and contralateral moderate or severe internal carotid artery stenosis

2001 ◽  
Vol 94 (4) ◽  
pp. 559-564 ◽  
Author(s):  
Fabrizio Vernieri ◽  
Patrizio Pasqualetti ◽  
Marina Diomedi ◽  
Patrizia Giacomini ◽  
Paolo M. Rossini ◽  
...  

Object. The purpose of this study was to evaluate cerebral hemodynamics in patients suffering from occlusion of the carotid artery (CA) and contralateral CA stenosis. Methods. Using transcranial Doppler ultrasonography, the cerebrovascular reactivity to hypercapnia in the middle cerebral arteries was evaluated by calculating the breath-holding index (BHI) of 69 symptomatic patients suffering from internal CA (ICA) occlusion and moderate or severe contralateral ICA stenosis. To evaluate which variables influenced BHIs ipsilateral to the site of ICA occlusion, a multiple stepwise linear regression analysis was performed that included the following factors: patient age, percentage of contralateral ICA stenosis, contralateral BHI, number of collateral pathways, and presence of hypertension, diabetes, smoking, and hyperlipidemia. An analysis of variance was conducted to evaluate the impact of the type of collateral vessels on the BHI. A regression analysis showed that the BHI ipsilateral to the site of ICA occlusion could be accounted for by the contralateral BHI (which was entered at the first step of the analysis, p < 0.001) and by the number of collateral pathways (which was entered at the second step, p = 0.033). Neither the degree of contralateral ICA stenosis nor the other variables could be added to improve the model. The analysis demonstrated that the absence of collateral pathways and the presence of the anterior communicating artery (ACoA) alone were associated with lower BHI values than those found in the presence of two or three collateral vessels, regardless of the presence of an anterior collateral pathway. Conclusions. On the basis of these data one can infer that the cerebral hemodynamic status of patients with occlusive disease of the CA is influenced by individual anatomical and functional characteristics. Because improvement in contralateral hemodynamics after surgical correction of an ICA stenosis can only be expected in the presence of an ACoA, the planning of strategies for influencing cerebral blood flow distal to an ICA occlusion and, in particular, the consideration of a contralateral carotid endarterectomy, should be preceded by a careful evaluation of the intracranial hemodynamic adaptive status of the patient. Particular attention should be paid to cerebrovascular reactivity and the number and type of collateral vessels that are present.

Neurology ◽  
2017 ◽  
Vol 90 (4) ◽  
pp. e307-e315 ◽  
Author(s):  
Simona Lattanzi ◽  
Luciano Carbonari ◽  
Gabriele Pagliariccio ◽  
Marco Bartolini ◽  
Claudia Cagnetti ◽  
...  

ObjectiveTo evaluate in patients with TIA and ipsilateral high-grade internal carotid artery (ICA) stenosis whether changes in cognitive performance and cerebral hemodynamics occurred after carotid endarterectomy (CEA) and to explore their relationship.MethodsParticipants were patients who underwent CEA, had TIA within the last 6 months, and had an ipsilateral severe ICA stenosis. Coloured Progressive Matrices (CPM) plus Complex Figure Copy Test (CFCT) and phonemic (ph) plus categorical (ca) Verbal Fluency (VF) tests were performed to assess right and left hemisphere cognitive functions, respectively. Hemodynamics was assessed with transcranial Doppler ultrasonography by means of the cerebral vasomotor reactivity (CVR) to hypercapnia.ResultsA total of 137 patients were included. Before CEA, patients with right ICA obtained lower scores on the CPM and CFCT; patients with left ICA stenosis performed worse on the phonemic and categorical VF tests. The CVR was decreased on the side of the stenosis. At 6 months from CEA, CVR and cognitive performance were significantly improved. The performance change in cognitive tests exploring the revascularized hemisphere was positively associated with the ipsilateral CVR variation (CPM: R2 for linear regression = 0.759, adjR2 = 0.737; CFCT: R2 = 0.734, adjR2 = 0.710; (ph)VF: R2 = 0.774, adjR2 = 0.749; (ca)VF: R2 = 0.732, adjR2 = 0.703).ConclusionCognitive performance was enhanced at 6 months since CEA, and the improvement was related to the CVR increase. Cerebral hemodynamics may be an independent and potentially reversible determinant of cognitive dysfunction in severe carotid artery disease.


1997 ◽  
Vol 87 (6) ◽  
pp. 940-943 ◽  
Author(s):  
Fernando L. Vale ◽  
Winfield S. Fisher ◽  
William D. Jordan ◽  
Cheryl A. Palmer ◽  
Jiri Vitek

✓ Carotid endarterectomy (CEA) is the treatment of choice for asymptomatic and symptomatic disease causing greater than 60% internal carotid artery (ICA) stenosis. Recently, percutaneous transluminal angioplasty (PTA) with stent placement has been investigated as a therapeutic option for the treatment of ICA stenosis. In this report the authors document CEA performed after PTA with stent placement and describe the pathological findings. A standard CEA was performed. The surgical intervention was more difficult secondary to the following variables: the length of the exposure necessary to dissect out the metallic stent, the difficulty with opening and cutting the artery, and the care required to remove the stent to avoid vessel wall perforation. Pathological examination of the specimen demonstrated classic atherosclerotic changes revealing persistence of native disease. The metallic stent was embedded within the plaque. Many questions remain unanswered regarding the physiological and biological changes that occur in the carotid vessel wall after PTA with stent placement. It is concluded that CEA of a stent-containing carotid artery is feasible and should be considered as an alternative when recurrent stenosis occurs after PTA.


1998 ◽  
Vol 89 (4) ◽  
pp. 667-670 ◽  
Author(s):  
Demetrius K. Lopes ◽  
Robert A. Mericle ◽  
Ajay K. Wakhloo ◽  
Lee R. Guterman ◽  
L. Nelson Hopkins

✓ The authors report the occurrence of ipsilateral transient cavernous sinus syndrome during balloon test occlusion (BTO) of the cervical internal carotid artery (ICA) and discuss the involved pathomechanisms. The authors reviewed their series of 129 BTOs of the ICA performed between 1989 and 1996. Two patients developed facial paresthesias and transient palsies of the third through sixth cranial nerves during test occlusion of the cervical ICA. The tests were performed prior to planned permanent carotid artery occlusion for the treatment of a neck sarcoma in one patient and a giant cavernous carotid artery aneurysm in the other. The patients' symptoms resolved with deflation of the balloon. When the balloon was subsequently inflated above the inferior cavernous sinus artery (ICSA), one of the patients complained of mild facial discomfort. There was no contralateral weakness or mental status change during test occlusion in either patient. Angiography demonstrated good filling of the ipsilateral intracranial circulation via collateral vessels of the circle of Willis. In these two cases, the cranial nerves in the cavernous sinus were likely supplied by the ICA via the meningohypophyseal trunk and the ICSA. In each case, there was excellent blood supply to the ipsilateral cerebral hemisphere; however, there was probably inadequate retrograde filling of the cranial nerve collateral vessels located where the meningohypophyseal trunk and ICSA originated. These cases emphasize the importance of a patent external carotid artery—ICA connection for successful cervical carotid artery occlusion. Neurological examination during BTO was critical to interpret the clinical manifestations caused by the hemodynamic changes.


1992 ◽  
Vol 76 (5) ◽  
pp. 752-758 ◽  
Author(s):  
Patrick W. McCormick ◽  
Robert F. Spetzler ◽  
Julian E. Bailes ◽  
Joseph M. Zabramski ◽  
James L. Frey

✓ A retrospective review of 42 patients (mean age 61.4 years) with surgically managed symptomatic internal carotid artery occlusion is reported. A standardized surgical protocol aimed at restoration of flow in the vessel was used. Presenting symptoms included hemispheric transient ischemic attacks in 68% of patients, new fixed neurological deficits in 28%, amaurosis fugax in 28%, and stroke-in-evolution in 9%. Twenty-four arteries were successfully reopened. A proximal remnant angioplasty (stumpectomy) was performed alone in nine patients or in combination with an external carotid endarterectomy in nine. In four patients with persisting symptoms who failed to achieve primary restoration of flow, a superficial temporal-to-middle cerebral artery bypass procedure was performed. The permanent surgical morbidity rate was 2% and the surgical mortality rate was 0%. Transient postoperative deficits were present in three patients (7%). Follow-up review at a mean of 40 months was obtained in 39 patients (93%). Following surgical intervention, five patients died of unrelated causes, two had neurological events consistent with a transient cerebral ischemic attack, and two had vertebrobasilar insufficiency. No patient suffered from stroke. Of the 24 successfully reopened vessels, follow-up ultrasound evaluations were obtained in 17 (73%) at a mean of 28 months after surgery. In 15 patients (88%) the vessels were widely patent, one (5.8%) had stenosis greater than 70%, and one (5.8%) showed asymptomatic reocclusion. Reopening occluded internal carotid arteries in selected patients is associated with low surgical morbidity and mortality rates. Further studies are necessary to determine the impact of this surgical therapy on the natural history of this condition.


1984 ◽  
Vol 61 (2) ◽  
pp. 254-262 ◽  
Author(s):  
A. Russell Lokkeberg ◽  
Richard M. Grimes

✓ An evaluation was made of the impact of non-treatment variables on severely injured head trauma patients. The principal findings were: 1) severity of injury was the best predictor of outcome; 2) patient's age had a statistically significant but marginally useful impact on outcome; 3) a regression analysis showed that duration of transport, up to 4 hours, had no impact on outcome; 4) time from accident to intubation had a marginal impact on outcome; and 5) one-way analysis of variance showed that mode of transportation, whether helicopter, ambulance, or other means had no impact on outcome.


2002 ◽  
Vol 96 (5) ◽  
pp. 830-836 ◽  
Author(s):  
Adnan I. Qureshi ◽  
M. Fareed K. Suri ◽  
Gishel New ◽  
Daniel C. Wadsworth ◽  
Joan Dulin ◽  
...  

Object. Carotid artery (CA) angioplasty with stent placement has been proposed as an alternative technique for revascularization in cases of CA stenosis. In this report the authors review the results of a multicenter Phase I study in which they evaluated the safety and feasibility of using a new self-expanding nitinol stent, the Bard Memotherm, to treat CA stenosis. Methods. Enrollment was limited to patients in whom there was either 50% or greater symptomatic or 70% or greater asymptomatic stenosis of the internal CA. The primary endpoint was a technically successful implantation procedure (delivery of the stent to the target site and retrieval of the delivery device), resulting in less than 30% residual stenosis demonstrated on immediate postprocedure (control) angiograms, and no incidence of mortality, ipsilateral stroke, Q-wave myocardial infarction, or other major cardiovascular events immediately after or within 30 days following the procedure. Stent placement was attempted for 73 lesions in 71 patients (mean age 71.3 ± 8.5 years), 43 (61%) of whom were men. The mean degree of stenosis was 82.6 ± 9%. The stenosis was symptomatic in 27 (37%) and asymptomatic in 46 (63%) of 73 lesions. In four procedures the stent could not be delivered or released. The mean residual stenosis observed on angiograms was 3.8 ± 6.9% in the 69 lesions treated with the Bard Memotherm stent; residual stenosis was greater than 30% in one of the 69 procedures. The primary endpoint was achieved in 65 (89%) of the 73 procedures. One patient experienced a major ischemic stroke and another patient died of intracerebral hemorrhage. The overall 1-month stroke rate was 2.7% for 73 attempted procedures. One patient died of pneumonia and acute respiratory distress syndrome, which occurred 3 weeks after the stent procedure and was unrelated to the procedure. Conclusions. The Memotherm stent can be used to treat patients with CA stenosis and is associated with a low periprocedure complication rate. Long-term follow-up studies are underway to determine the impact of stent placement on the risk of ipsilateral ischemic events.


1971 ◽  
Vol 35 (5) ◽  
pp. 571-576 ◽  
Author(s):  
Aneel N. Patel ◽  
Alan E. Richardson

✓ An analysis of 3000 ruptured intracranial aneurysms revealed 58 cases in patients under the age of 19 years. There was a striking incidence of aneurysms of the carotid termination and anterior cerebral complex, accounting for 43 of 58 cases, and of these 20 involved the terminal portion of the carotid artery. Vasospasm occurred slightly less often than in adults and infarction was only seen in one postmortem examination. The surgical mortality in alert patients was 7% whereas in a comparable bedrest group it was 38%. This good tolerance to surgery was evident whether intracranial operation or carotid ligation was used, but the surgical method was not randomly allocated.


2016 ◽  
Vol 16 (3) ◽  
pp. 307-322 ◽  
Author(s):  
Hossein Karimi ◽  
Timothy R.B. Taylor ◽  
Paul M. Goodrum ◽  
Cidambi Srinivasan

Purpose This paper aims to quantify the impact of craft worker shortage on construction project safety performance. Design/methodology/approach A database of 50 North American construction projects completed between 2001 and 2014 was compiled by taking information from a research project survey and the Construction Industry Institute Benchmarking and Metrics Database. The t-test and Mann-Whitney test were used to determine whether there was a significant difference in construction project safety performance on projects with craft worker recruiting difficulty. Poisson regression analysis was then used to examine the relationship between craft worker recruiting difficulty and Occupational Safety and Health Administration Total Number of Recordable Incident Cases per 200,000 Actual Direct Work Hours (TRIR) on construction projects. Findings The result showed that the TRIR distribution of a group of projects that reported craft worker recruiting difficulty tended to be higher than the TRIR distribution of a group of projects with no craft worker recruiting difficulty (p-value = 0.004). Moreover, the average TRIR of the projects that reported craft worker recruiting difficulty was more than two times the average TRIR of projects that experienced no craft recruiting difficulty (p-value = 0.035). Furthermore, the Poisson regression analysis demonstrated that there was a positive exponential relationship between craft worker recruiting difficulty and TRIR in construction projects (p-value = 0.004). Research limitations/implications The projects used to construct the database are heavily weighted towards industrial construction. Practical implications There have been significant long-term gains in construction safety within the USA. However, if recent craft shortages continue, the quantitative analyses presented herein indicate a strong possibility that more safety incidents will occur unless the shortages are reversed. Innovative construction means and methods should be developed and adopted to work in a safe manner with a less qualified workforce. Originality/value The Poisson regression model is the first model that quantifiably links project craft worker availability to construction project safety performance.


2002 ◽  
Vol 96 (6) ◽  
pp. 1013-1019 ◽  
Author(s):  
Rupert Kett-White ◽  
Peter J. Hutchinson ◽  
Pippa G. Al-Rawi ◽  
Marek Czosnyka ◽  
Arun K. Gupta ◽  
...  

Object. The aim of this study was to investigate potential episodes of cerebral ischemia during surgery for large and complicated aneurysms, by examining the effects of arterial temporary clipping and the impact of confounding variables such as blood pressure and cerebrospinal fluid (CSF) drainage. Methods. Brain tissue PO2, PCO2, and pH, as well as temperature and extracellular glucose, lactate, pyruvate, and glutamate were monitored in 46 patients by using multiparameter sensors and microdialysis. Baseline data showed that brain tissue PO2 decreased significantly, below a mean arterial pressure (MAP) threshold of 70 mm Hg. Further evidence of its relationship with cerebral perfusion pressure was shown by an increase in mean brain tissue PO2 after drainage of CSF from the basal cisterns (Wilcoxon test, p < 0.01). Temporary clipping was required in 31 patients, with a mean total duration of 14 minutes (range 3–52 minutes), causing brain tissue PO2 to decrease and brain tissue PCO2 to increase (Wilcoxon test, p < 0.01). In patients in whom no subsequent infarction developed in the monitored region, brain tissue PO2 fell to 11 mm Hg (95% confidence interval 8–14 mm Hg). A brain tissue PO2 level below 8 mm Hg for 30 minutes was associated with infarction in any region (p < 0.05 according to the Fisher exact test); other parameters were not predictive of infarction. Intermittent occlusions of less than 30 minutes in total had little effect on extracellular chemistry. Large glutamate increases were only seen in two patients, in both of whom brain tissue PO2 during occlusion was continuously lower than 8 mm Hg for longer than 38 minutes. Conclusions. The brain tissue PO2 decreases with hypotension, and, when it is below 8 mm Hg for longer than 30 minutes during temporary clipping, it is associated with increasing extracellular glutamate levels and cerebral infarction.


2014 ◽  
Vol 19 (2) ◽  
pp. 69-82 ◽  
Author(s):  
Ahmet Yildiz ◽  
Sidika Kaya

Purpose – This article aims to investigate perceptions of Turkish nurses on the impact of accreditation on quality of care and the effect of accreditation on quality results. Design/methodology/approach – This study was performed as a cross-sectional, questionnaire-based survey on 258 nurses who started working in the hospital before it was accredited and continued to work during and after accrediation and who therefore knew both the hospital's pre-accrediation and post-accreditation periods. In this study, descriptive statistical analyses (means and standard deviations) were carried out to explore the views of the participants on “quality results,” “benefits of accreditation” and “participation of employees.” “Quality results” was considered to be the dependent variable, while “benefits of accreditation” and “participation of employees” were accepted as the independent variables. The relationship between the dependent variable and the independent variables was tested using Pearson correlation and multiple regression analysis. External patient satisfaction data collected by the quality department of the hospital before and after accreditation were also investigated. Findings – It was found that nurses had generally high scores for the items concerning the benefits of accreditation. There was a statistically significant positive correlation between the dependent variable (quality results) and the independent variables (benefits of accreditation and participation of employees). Regression analysis indicated that R2=0.461 and the extent to which the independent variables explained the dependent variable was 46.1 per cent, which is a high rate. Patient satisfaction scores increased after accreditation. Practical implications – Our study suggest that providing support for nurses, especially nurses with administrative responsibilities and incorporating employees into the process are important for exercising quality standards. Originality/value – Hospital accreditation has a positive impact on quality results especially on quality of care provided to patients and patient satisfaction. Study findings could guide policy makers and hospital managers in Turkey and in other countries who are preparing or implementing accreditation.


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