Iszet Campo-Bustillo

Cerebral Fat Microembolism and Cognitive Decline After Hip and Knee Replacement

Background and Purpose— Intra-operative cerebral microembolism may be a factor in the etiology of cognitive decline after orthopedic surgery. We here examine the impact of intra-operative microembolism on cognitive dysfunction after hip and knee replacement surgery. Methods— We enrolled 24 patients, at least 65 years old, requiring elective knee or hip replacement surgery. A transcranial Doppler shunt study was done to determine study eligibility so that the final study population consisted of 12 consecutive patients with and 12 consecutive patients without a venous-arterial shunt. A standard neuropsychological test battery was administered before surgery, at hospital discharge and 3 months after surgery. All patients were monitored intra-operatively for microemboli. Quality of life data were assessed at 1 year. Results— The mean age of patients was 74 years. All patients had intra-operative microemboli. The mean number of emboli was 9.9±18. Cognitive decline was present in 18/22 (75%) at discharge and in 10/22 (45%) at 3 months, despite improved quality of life measures. There was no correlation between cognitive decline and intra-operative microembolism. Conclusion— Cognitive decline was seen frequently after hip and knee surgery. Intra-operative microembolism occurred universally but did not significantly influence postoperative cognition. Quality of life and functional outcome demonstrated improvement in all cases in spite of cognitive dysfunction.

Outcomes in mild acute ischemic stroke treated with intravenous thrombolysis: a retrospective analysis of the Get With the Guidelines-Stroke registry.

IMPORTANCE Mild strokes have been poorly represented in thrombolytic trials and only a few series have reported outcomes after treatment with intravenous (IV) recombinant tissue plasminogen activator (rtPA) after mild stroke. OBJECTIVE To report treatment complications and short-term outcomes in patients with mild stroke who have received treatment with IV rtPA. DESIGN, SETTING, AND PARTICIPANTS Retrospective analysis of patients treated in the emergency department of hospitals that use the Get With the Guidelines-Stroke registry, a prospectively collected quality improvement registry used by hospitals across the United States. Patients were those admitted between May 1, 2010, and October 1, 2012, with acute ischemic stroke within 4.5 hours from symptom onset and a baseline National Institutes of Health Stroke Scale score of 5 or less. Univariable and multivariable analyses were performed to identify factors independently associated with discharge outcomes and treatment complications. INTERVENTION Intravenous rtPA. MAIN OUTCOMES AND MEASURES Treatment complications included symptomatic intracranial hemorrhage, life-threatening or serious systemic hemorrhage, other serious complications, and undetermined complications. The short-term outcomes analyzed were in-hospital mortality, discharge to home, independent ambulation at discharge, and length of stay. RESULTS Among 33,995 patients who arrived within 4.5 hours of symptom onset and were treated with IV rtPA, 7621 (22.4%) had a National Institutes of Health Stroke Scale score of 5 or less and 5910 had complete data for analysis. Treatment complications were infrequent: symptomatic intracranial hemorrhage, 1.8%; life-threatening or serious systemic hemorrhage, 0.2%; other serious complications, 1.8%; and complications of undetermined cause, 2.4%. Mortality was low (1.3%), but at discharge 30.3% could not ambulate independently, 29.4% could not go directly home, and 73.0% had a length of stay of 3 days or longer. Worse short-term outcomes were seen in older patients, African American patients, diabetic patients, and those who arrived by ambulance, after hours, or with a higher National Institutes of Health Stroke Scale score. CONCLUSIONS AND RELEVANCE Many patients with ischemic stroke treated with IV rtPA have a mild stroke. Symptomatic intracranial hemorrhage is infrequent, but approximately 30% of these patients are unable to return directly home or ambulate independently at discharge. Additional studies are needed to identify strategies to improve the outcomes in patients with mild stroke who receive thrombolysis.

Microemboli in Aneurysmal Subarachnoid Hemorrhage

The determinants of ischemic complications in subarachnoid hemorrhage (SAH) are not well defined. The objective of this study is to evaluate the role of microemboli in SAH‐related cerebral ischemia.

Transcranial Doppler Detection of Cerebral Fat Emboli and Relation to Paradoxical Embolism A Pilot Study

Background— The fat embolism syndrome is clinically characterized by dyspnea, skin petechiae, and neurological dysfunction. It is associated mainly with long bone fracture and bone marrow fat passage to the systemic circulation. An intracardiac right-to-left shunt (RLS) could allow larger fat particles to reach the systemic circulation. Transcranial Doppler can be a useful tool to detect both RLS and the fat particles reaching the brain. Methods and Results— We prospectively studied patients with femur shaft fracture with RLS evaluation, daily transcranial Doppler with embolus detection studies, and neurological examinations to evaluate the relation of RLS and microembolic signals to the development of fat embolism syndrome. Forty-two patients were included; 14 had an RLS detected. Seven patients developed neurological symptoms; all of them had a positive RLS (P=<0.001). The patients with an RLS showed higher counts and higher intensities of microembolic signals (P=<0.05 and P=<0.01, respectively) compared with those who did not have an RLS identified. The presence of high microembolic signal counts and intensities in patients with RLS was strongly predictive of the occurrence of neurological symptoms (odds ratio, 204; 95% confidence interval, 11 to 3724; P<0.001) with a positive predictive value of 86% and negative predictive value of 97%. Conclusions— In patients with long bone fractures, the presence of an RLS is associated with larger and more frequent microembolic signals to the brain detected by transcranial Doppler study and can predict the development of neurological symptoms.

High-Dose Atorvastatin Enhances Impaired Cerebral Vasomotor Reactivity

The influence of statin therapy on cerebral vasomotor function has not been fully characterized. We report the effects of high-dose atorvastatin therapy on cerebral vasomotor reactivity (VMR) in patients with controlled hypertension and dyslipidemia. We prospectively enrolled 36 patients with controlled hypertension and a low-density lipoprotein (LDL) cholesterol concentration >100 mg/dL. Atorvastatin 80 mg was given daily for 6 months and then discontinued. VMR was assessed by hypercapnic and hypocapnic transcranial Doppler challenge in both the right and left middle cerebral artery (MCA) at baseline, and after 3 and 6 months of therapy. Forty-five days after statin cessation, a repeat VMR was performed. VMR impairment was defined as ≤70%. Blood pressure, lipid levels, liver function, and creatine kinase level were monitored. Mean patient age was 60 years, 16 were men, and 13 had a previous history of subcortical infarction. Mean LDL cholesterol level before treatment was 154 ± 30 mg/dL. Atorvastatin lowered LDL by 53% at 3 months and by 46% at 6 months. Baseline VMR was 71% ± 21% in the right MCA and 70% ± 19% in the left MCA. No significant effect of atorvastatin on VMR was seen at 3 months and 6 months in the study population as a whole. In the subgroup of patients with baseline VMR impairment, atorvastatin therapy was associated with significantly improved VMR at both 3 and 6 months. This effect persisted for at least 45 days after discontinuation of therapy. Our findings indicate that high-dose atorvastatin therapy can significantly improve impaired cerebral VMR, and that the effects of atorvastatin on VMR persist for 1.5 months after discontinuation of therapy. We found no benefit of atorvastatin therapy in patients with preserved baseline vasoreactivity.

MR Imaging after Hip and Knee Replacement

Diffusion‐weighted (DW) imaging abnormalities often develop in patients after invasive procedures associated with cerebral microembolism. Cerebral microembolism has recently been shown during orthopedic surgery. We here examine the effects of intraoperative microembolism on acute magnetic resonance(MR) imaging in patients undergoing hip and knee replacement.

Distinct Short-Term Outcomes in Patients With Mild Versus Rapidly Improving Stroke Not Treated With Thrombolytics

Background and Purpose— Mild stroke (MS) and rapidly improving stroke (RIS) symptoms are common stroke presentations. Our objective is to describe the short-term outcomes in this population. Methods— A retrospective analysis of patients with ischemic stroke in the Get With The Guidelines–Stroke registry who arrived ⩽4.5 hours from symptom onset not treated with thrombolytics because of MS and RIS. Outcomes included in-hospital death, home discharge, independent ambulation at discharge, and length of stay; these were analyzed for the categories of MS, RIS, and MS+RIS. Multivariable models evaluated the associations of individual and hospital covariates with outcomes. Results— Among 42 394 patients with MS and RIS not treated with thrombolytics, 27% were not discharged directly home, 27.2% did not ambulate independently, and 61.1% had length of stay ≥3 days, despite a low in-hospital mortality of 0.8%. Adjusted outcomes were better for MS+RIS compared with MS; RIS also had better independent ambulation and home discharge compared with MS. Among those with a documented National Institutes of Health Stroke Scale, 25% of those with National Institutes of Health Stroke Scale 0 to 5 and half of those with National Institutes of Health Stroke Scale >5 could not be discharged directly to home or ambulate independently. Older individuals, women, blacks, transport by ambulance, delayed arrival, greater severity and greater burden of vascular risk factors, except for dyslipidemia, had worse adjusted outcomes for home discharge and independent ambulation. Conclusions— A significant proportion of patients with MS and RIS not treated with thrombolytics have suboptimal discharge outcomes. We found significant differences between MS, RIS, and MS+RIS and identified factors associated with worse outcomes.

Moderate correlation between breath-holding and CO(2) inhalation/hyperventilation methods for transcranial doppler evaluation of cerebral vasoreactivity.

Both CO2 inhalation followed by hyperventilation and breath‐holding have been utilized to measure cerebral vasomotor reactivity (VMR) but their correlation has been poorly studied and understood.

Transcranial Doppler Detection of Cerebral Fat Emboli and Relation to Paradoxical Embolism

Background— The fat embolism syndrome is clinically characterized by dyspnea, skin petechiae, and neurological dysfunction. It is associated mainly with long bone fracture and bone marrow fat passage to the systemic circulation. An intracardiac right-to-left shunt (RLS) could allow larger fat particles to reach the systemic circulation. Transcranial Doppler can be a useful tool to detect both RLS and the fat particles reaching the brain. Methods and Results— We prospectively studied patients with femur shaft fracture with RLS evaluation, daily transcranial Doppler with embolus detection studies, and neurological examinations to evaluate the relation of RLS and microembolic signals to the development of fat embolism syndrome. Forty-two patients were included; 14 had an RLS detected. Seven patients developed neurological symptoms; all of them had a positive RLS (P=<0.001). The patients with an RLS showed higher counts and higher intensities of microembolic signals (P=<0.05 and P=<0.01, respectively) compared with those who did not have an RLS identified. The presence of high microembolic signal counts and intensities in patients with RLS was strongly predictive of the occurrence of neurological symptoms (odds ratio, 204; 95% confidence interval, 11 to 3724; P<0.001) with a positive predictive value of 86% and negative predictive value of 97%. Conclusions— In patients with long bone fractures, the presence of an RLS is associated with larger and more frequent microembolic signals to the brain detected by transcranial Doppler study and can predict the development of neurological symptoms.

Transcranial Doppler Detection of Cerebral Fat Emboli and Relation to Paradoxical EmbolismClinical Perspective: A Pilot Study

Background— The fat embolism syndrome is clinically characterized by dyspnea, skin petechiae, and neurological dysfunction. It is associated mainly with long bone fracture and bone marrow fat passage to the systemic circulation. An intracardiac right-to-left shunt (RLS) could allow larger fat particles to reach the systemic circulation. Transcranial Doppler can be a useful tool to detect both RLS and the fat particles reaching the brain. Methods and Results— We prospectively studied patients with femur shaft fracture with RLS evaluation, daily transcranial Doppler with embolus detection studies, and neurological examinations to evaluate the relation of RLS and microembolic signals to the development of fat embolism syndrome. Forty-two patients were included; 14 had an RLS detected. Seven patients developed neurological symptoms; all of them had a positive RLS (P=<0.001). The patients with an RLS showed higher counts and higher intensities of microembolic signals (P=<0.05 and P=<0.01, respectively) compared with those who did not have an RLS identified. The presence of high microembolic signal counts and intensities in patients with RLS was strongly predictive of the occurrence of neurological symptoms (odds ratio, 204; 95% confidence interval, 11 to 3724; P<0.001) with a positive predictive value of 86% and negative predictive value of 97%. Conclusions— In patients with long bone fractures, the presence of an RLS is associated with larger and more frequent microembolic signals to the brain detected by transcranial Doppler study and can predict the development of neurological symptoms.