Distinguishing Between Stroke and Mimic at the Bedside

BACKGROUND AND PURPOSE

The bedside clinical assessment of the patient with suspected stroke has not been well studied. Improving clinical skills may accelerate patient progress through the emergency department. We aimed to determine the frequency and nature of stroke mimics and to identify the key clinical features that distinguish between stroke and mimic at the bedside.

METHODS

Consecutive presentations to an urban teaching hospital with suspected stroke were recruited. A standard bedside clinical assessment was performed. The final diagnosis was determined by an expert panel, which had access to clinical features, brain imaging, and other tests. Univariate and multivariate analyses determined the bedside features that distinguished stroke from mimic.

RESULTS

There were 350 presentations by 336 patients. The final diagnosis was stroke in 241 of 350 (69%) and mimic in 109 (31%). The mimics included 44 events labeled "possible stroke or TIA." Eight items independently predicted the diagnosis in patients presenting with brain attack: cognitive impairment and abnormal signs in other systems suggested a mimic, an exact time of onset, definite focal symptoms, abnormal vascular findings, presence of neurological signs, being able to lateralize the signs to the left or right side of the brain, and being able to determine a clinical stroke subclassification suggested a stroke.

CONCLUSIONS

The bedside clinical assessment can be streamlined substantially. This has important implications for teaching less experienced clinicians how to assess the patient with suspected stroke.

A systematic review of barriers to delivery of thrombolysis for acute stroke

BACKGROUND AND PURPOSE

Barriers within the patient pathway can prevent early administration of thrombolytic therapy in patients admitted with acute stroke. This systematic review aimed to identify such barriers that have been reported in the medical literature.

METHODS

We searched MEDLINE and EMBASE for prospective and retrospective observational studies that assessed the nature of barriers to delivery of thrombolysis for acute stroke.

RESULTS

We identified 54 eligible studies (including a total of 39030 patients). The reported barriers included: (i). the patient or family did not recognise symptoms of stroke or seek urgent help, (ii). the general practitioner (rather than an ambulance) was called first, (iii). the paramedics and emergency department staff triaged stroke as non-urgent, (iv). delays in neuroimaging, (v). inefficient process of in-hospital emergency stroke care, (vi). difficulties in obtaining consent for thrombolysis, and (vii). physicians' uncertainty about administering thrombolysis.

CONCLUSIONS

We identified important pre-hospital and in-hospital barriers that should be overcome if thrombolysis is to be administered to stroke patients efficiently and equitably.

Evidence for inverse agonism of SR141716A at human recombinant cannabinoid CB1 and CB2 receptors

The cannabinoid receptor antagonist SR141716A has been suggested to be an inverse agonist at CB1 receptors in some isolated intact tissues. We found that the basal incorporation of [35S]-GTPgammaS in Chinese hamster ovary cells expressing human recombinant CB1 and CB2 receptors was inhibited by SR141716A (mean pEC50s 8.26 and 6.00, respectively), whereas cannabinol (10 microM) had no significant effect at hCB1 receptors but inhibited the binding at hCB2 receptors. As cannabinol had no effect on basal [35S]-GTPmicroS binding at hCB1 at a concentration 100 fold higher than its binding affinity (K = 0.1 microM), we conclude that endogenous cannabinoid receptor agonists are not a confounding factor and suggest the actions of SR141716A at the hCB1 receptor, and the actions of SR141716A and cannabinol at the hCB2 receptor, are due to inverse agonism.

Early neurological deterioration in acute stroke: clinical characteristics and impact on outcome

BACKGROUND

A significant proportion of acute stroke patients suffer neurological deterioration during the first few days of recovery.

AIM

To explore the frequency, clinical characteristics, and consequences of early neurological deterioration during the acute recovery period.

METHODS

We assessed all consecutive patients admitted to a University hospital with suspected stroke. We recorded the following on admission: baseline characteristics, physiological parameters and laboratory results. On day 5 we recorded occurrence of complications, and functional outcome. Early neurological deterioration was defined as an increase in National Institute of Health Stroke Score (NIHSS) by two or more points (or stroke-related death) between admission and day 5.

RESULTS

We recruited 188 stroke patients, of whom 36 (19%) suffered early neurological deterioration. Patients with early neurological deterioration were significantly more likely to: (i) arrive at the hospital earlier (median 2.25 vs. 7.2 h, p = 0.015); (ii) have a history of atrial fibrillation (33% vs. 16%, p = 0.039); (iii) be current non-smokers (24% vs. 11%, p = 0.041); (iv) have a severe stroke-more total anterior circulation strokes (67% vs. 26%, p < 0.001) and worse NIHSS and GCS scores; (v) have intracerebral haemorrhage (22% vs. 7%, p = 0.011); (vi) have higher serum urea (mean 7.8 vs. 6.5 mmol/l, p = 0.035) and leukocyte count (mean 12.6 vs. 9.7 x 10(9)/l, p = 0.044); and (vi) die in hospital (44% vs. 10%, OR 12.8, 95%CI 3.8-43.1, p < 0.001).

DISCUSSION

Early neurological deterioration is a frequent and important complication in acute stroke, with a poor short-term prognosis. Effective treatment strategies are urgently needed to reduce its occurrence and impact on recovery.

Global Impact of COVID-19 on Stroke Care and IV Thrombolysis

OBJECTIVE

To measure the global impact of COVID-19 pandemic on volumes of IV thrombolysis (IVT), IVT transfers, and stroke hospitalizations over 4 months at the height of the pandemic (March 1 to June 30, 2020) compared with 2 control 4-month periods.

METHODS

We conducted a cross-sectional, observational, retrospective study across 6 continents, 70 countries, and 457 stroke centers. Diagnoses were identified by their ICD-10 codes or classifications in stroke databases.

RESULTS

There were 91,373 stroke admissions in the 4 months immediately before compared to 80,894 admissions during the pandemic months, representing an 11.5% (95% confidence interval [CI] -11.7 to -11.3, p < 0.0001) decline. There were 13,334 IVT therapies in the 4 months preceding compared to 11,570 procedures during the pandemic, representing a 13.2% (95% CI -13.8 to -12.7, p < 0.0001) drop. Interfacility IVT transfers decreased from 1,337 to 1,178, or an 11.9% decrease (95% CI -13.7 to -10.3, p = 0.001). Recovery of stroke hospitalization volume (9.5%, 95% CI 9.2-9.8, p < 0.0001) was noted over the 2 later (May, June) vs the 2 earlier (March, April) pandemic months. There was a 1.48% stroke rate across 119,967 COVID-19 hospitalizations. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was noted in 3.3% (1,722/52,026) of all stroke admissions.

CONCLUSIONS

The COVID-19 pandemic was associated with a global decline in the volume of stroke hospitalizations, IVT, and interfacility IVT transfers. Primary stroke centers and centers with higher COVID-19 inpatient volumes experienced steeper declines. Recovery of stroke hospitalization was noted in the later pandemic months.

Infection after acute stroke is associated with poor short-term outcome

BACKGROUND

We sought to explore the frequency, risk factors, and clinical consequences of post-stroke infections (PSI).

METHODS

We assessed consecutive patients admitted with suspected stroke. On day 1, we recorded the patients' baseline characteristics, stroke subtype and severity, physiological parameters, and laboratory results. On day 5, we recorded the occurrence of complications including infections, and functional outcome.

RESULTS

We recruited 439 patients [398 with stroke and 41 with transient ischaemic attack (TIA)], of whom 73 (17%) had PSI (67 with stroke and 6 with TIA) by day 5. Compared to patients without PSI, those with PSI were significantly more likely to: (i) be older (mean age 78 vs 73 years, P=0.001); (ii) be dependent before admission (47% vs 24%, P<0.001); (iii) have total anterior circulation strokes (40% vs 20%, P<0.001); (iv) be hypoxic on arrival (35% vs 17%, P=0.001); (v) have urinary catheters (43% vs 16%, P<0.001), and (vi) develop pressure sores (7% vs 2%, P=0.022) and seizures (12% vs 2%, P<0.001). After adjusting for case mix, PSI was significantly associated with in-hospital death (OR 2.50, 95% CI 1.27-4.90, P=0.008) and institutionalization on discharge (OR 1.86, 95% CI 1.00-3.43, P=0.049).

CONCLUSIONS

Post-stroke infection can affect patients admitted with TIA as well as acute stroke, and it may be associated with poor short-term outcomes.

Cost-effectiveness of thrombolysis with recombinant tissue plasminogen activator for acute ischemic stroke assessed by a model based on UK NHS costs

BACKGROUND AND PURPOSE

Thrombolytic therapy is licensed for use in highly selected patients with acute ischemic stroke. We aimed to model the health economic impact of limited use of thrombolytic therapy and to assess whether it was likely to be cost-effective when used more widely in the UK National Health Service (NHS).

METHODS

The authors formed a discussion panel to develop the decision-analysis model of acute stroke care. It consisted of Markov state-transition processes, with probabilities of different health states determined by certain key variables. The range of estimates of efficacy of recombinant tissue plasminogen activator (rt-PA) was taken from an update to a Cochrane systematic review of randomized trials of thrombolysis. Data on outcome after stroke were taken from our hospital-based stroke register, supplemented by data derived from relevant literature sources.

RESULTS

The model suggested that compared with standard care, if eligible patients were treated with rt-PA up to 6 hours, there was a 78% probability of a gain in quality-adjusted survival during the first year, at a cost of pound 13 581 per quality-adjusted life-year (QALY) gained. Over a lifetime, rt-PA was associated with cost-savings of pound 96 565 per QALY. However, the estimates were imprecise and highly susceptible to the assumptions used in the economic model; under several plausible assumptions, rt-PA was much less cost-effective than standard care, and under others, a great deal more cost-effective.

CONCLUSIONS

The estimates of effectiveness and cost-effectiveness were imprecise. Although the benefits appeared promising, the data did not support the widespread use of thrombolytic therapy outside the terms of the current restricted license in routine clinical practice in the NHS. There is a case for new large-scale randomized trials comparing thrombolytic therapy with control up to 6 hours to determine more precisely the effects of rt-PA on short-term and long-term survival and its cost-effectiveness when used in a wider range of patients.

Fall risk-assessment tools compared with clinical judgment: an evaluation in a rehabilitation ward

OBJECTIVES

to compare the use of two falls risk-identification tools (Downton and STRATIFY) with clinical judgment (based upon the observation of wandering behaviour) in predicting falls of medically stable patients in a rehabilitation ward for older people.

METHODS

in a prospective observational study, with blinded end-point evaluation, 200 patients admitted to a geriatric rehabilitation hospital had a STRATIFY and Downton Fall Risk assessment and were observed for wandering behaviour.

RESULTS

wandering had a predictive accuracy of 78%. A total of 157/200 were identified correctly compared to 100/200 using the Downton score (P < 0.0001 95%, CI 0.18-0.42), or 93/200 using STRATIFY (P < 0.0001; 95% CI 0.15-0.37). The Downton and STRATIFY tools demonstrated predictive accuracies of 50% and 46.5%, respectively, with no statistical significance between the two (P = 0.55; 95% CI 0.77-1.71). Sensitivity for predicting falls using wandering was 43.1% (22/51). This was significantly worse than Downton 92.2% (47/51: P < 0.001) and STRATIFY 82.3% (42/51: P < 0.001).

CONCLUSIONS

this study showed that clinical observation had a higher accuracy than two used falls risk-assessment tools. However it was significantly less sensitive implying that fewer patients who fell were correctly identified as being at risk.

Improving the efficiency of delivery of thrombolysis for acute stroke: a systematic review

BACKGROUND

Thrombolytic therapy with recombinant tissue plasminogen activator (rt-PA) is licensed for use within 3 h of acute ischaemic stroke. The less the delay to treatment, the more likely it is to be effective.

AIMS

To assess the effectiveness of interventions designed to overcome barriers to rapid administration of thrombolytic therapy.

DESIGN

Systematic review of previous clinical studies.

METHODS

We searched for studies that evaluated the effect of an intervention to reduce delays to administration of rt-PA. We searched MEDLINE, EMBASE, the trials register of the Cochrane Stroke Group, and the Cochrane Controlled Trials Register. We sought randomized and non-randomized controlled trials, before-and-after studies, interrupted time series, and observational studies.

RESULTS

We identified 10 non-randomized studies that evaluated interventions that could speed up admission to hospital and administration of rt-PA. The types of interventions included: (a) education programmes for the public to improve their knowledge about symptoms of acute stroke; (b) training programmes for paramedical staff to improve their accuracy of stroke diagnosis and hasten transport of the patient to hospital; (c) helicopter transfer of patients to hospital; (d) training programmes in acute stroke therapy for emergency department staff; and (e) re-organization of in-hospital systems to streamline acute stroke care. Several programmes were multifaceted interventions.

DISCUSSION

We identified important areas that could be targets for interventions to improve the efficiency of delivering thrombolysis for acute stroke. Multifaceted programmes might be more likely to be successful in reducing delays to therapy.

In-hospital care pathways for stroke

BACKGROUND

Stroke care pathways have the potential to promote organised and efficient patient care that is based on best evidence and guidelines, but evidence to support their use is unclear.

OBJECTIVES

We aimed to assess the effects of care pathways, compared with standard medical care, among patients with acute stroke who had been admitted to hospital.

SEARCH STRATEGY

We searched the Cochrane Stroke Group Trials Register (last searched in June 2003), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 2, 2003), MEDLINE (1975 to June 2003), EMBASE (1980 to June 2003), CINAHL (1982 to June 2003), ISI Proceedings: Science & Technology (1990 to November 2003), and HealthSTAR (1994 to May 2001). We also handsearched the Journal of Integrated Care Pathways (2001 to 2003), formerly Journal of Managed Care (1997 to 1998) and Journal of Integrated Care (1998 to 2001). Reference lists of articles were searched.

SELECTION CRITERIA

We considered randomised controlled trials and non-randomised studies that compared care pathway care with standard medical care.

DATA COLLECTION AND ANALYSIS

One reviewer selected studies for inclusion and the other independently checked the decisions. Two reviewers independently assessed the methodological quality of the studies. One reviewer extracted the data and the other checked the extracted data.

MAIN RESULTS

Three randomised controlled trials (340 patients) and 12 non-randomised studies (4081 patients) were included. There was significant statistical heterogeneity in the analysis of many of the outcomes. We found no significant difference between care pathway and control groups in terms of death or discharge destination. Patients managed with a care pathway were: (a) more dependent at discharge (P = 0.04); (b) less likely to suffer a urinary tract infection (Odds Ratio (OR) 0.51, 95% Confidence Interval (CI) 0.34 to 0.79); (c) less likely to be readmitted (OR 0.11, 95% CI 0.03 to 0.39); and (d) more likely to have neuroimaging (OR 2.42, 95% CI 1.12 to 5.25). Evidence from randomised trials suggested that patient satisfaction and quality of life were significantly lower in the care pathway group (P = 0.02 and P < 0.005 respectively).

REVIEWERS' CONCLUSIONS

Use of stroke care pathways may be associated with positive and negative effects. Since most of the results have been derived from non-randomised studies, they are likely to be influenced by potential biases and confounding factors. There is currently insufficient supporting evidence to justify the routine implementation of care pathways for acute stroke management or stroke rehabilitation.

Circulating tumor necrosis factor-alpha concentrations in a native Canadian population with high rates of type 2 diabetes mellitus

Recent research suggests that tumor necrosis factor-alpha (TNF alpha) may play an important role in obesity-associated insulin resistance and diabetes. We studied the relationship between TNF alpha and the anthropometric and physiological variables associated with insulin resistance and diabetes in an isolated Native Canadian population with very high rates of type 2 diabetes mellitus (DM). A stratified random sample (n = 80) of participants was selected from a population-based survey designed to determine the prevalence of type 2 DM and its associated risk factors. Fasting blood samples for glucose, insulin, triglyceride, leptin, and TNF alpha were collected; a 75-g oral glucose tolerance test was administered, and a second blood sample was drawn after 120 min. Insulin resistance was estimated using the homeostasis assessment (HOMA) model. Systolic and diastolic blood pressure (BP), height, weight, and waist and hip circumferences were determined, and percent body fat was estimated using biological impedance analysis. The relationship between circulating concentrations of TNF alpha and the other variables was assessed using Spearman correlation coefficients, analysis of covariance, and multiple linear regression. The mean TNF alpha concentration was 5.6 pg/mL (SD = 2.18) and ranged from 2.0-12.9 pg/mL, with no difference between men and women (P = 0.67). There were moderate, but statistically significant, correlations between TNF alpha and fasting insulin, HOMA insulin resistance (HOMA IR) waist circumference, fasting triglyceride, and systolic BP (r = 0.23-0.34; all P < 0.05); in all cases, coefficients for females were stronger than those for males. Individuals with normal glucose tolerance had lower log TNF alpha concentrations than those with impaired glucose tolerance or type 2 DM (both P = 0.03, adjusted for age and sex), although differences were not significant after adjustment for HOMA IR (both P > 0.25). Regression analysis indicated that log HOMA IR and log systolic BP were significant independent contributors to variations in log TNF alpha concentration (model r2 = 0.32). We conclude that in this homogeneous Native Canadian population, circulating TNF alpha concentrations are positively correlated with insulin resistance across a spectrum of glucose tolerance. The data suggest a possible role for TNF alpha in the pathophysiology of insulin resistance.

Fear of recurrence and beliefs about preventing recurrence in persons who have suffered a stroke

OBJECTIVES

The aim of this study was to investigate fear of recurrent stroke and beliefs about its causes and prevention.

METHODS

Eighty-nine patients participated 1 month following stroke and 81 were followed up at 9 months. Interviews addressed fears and beliefs about stroke, causes, recurrence and prevention by using closed and open-ended questions. Responses were subject to quantitative and qualitative analysis, respectively.

RESULTS

Fear of recurrence was common. Profound disability was a particularly feared outcome. Participants were knowledgeable about causes. However, causal controllability ratings were low. Some reported concern about preventative strategies (e.g., difficulty stopping smoking). Many reported idiosyncratic beliefs (e.g., avoiding overexertion) or fatalistic ideas about strokes (e.g., 'nothing' can prevent them). Similar quantitative results were obtained at follow-up.

CONCLUSIONS

Many patients fear stroke recurrence. They lack a sense of control over causes and have fears associated with idiosyncratic and fatalistic beliefs. There is a need to elicit and address individuals' own fears and beliefs about stroke before providing evidence-based secondary prevention recommendations.

Ras-independent transformation by v-Src

Signaling by a variety of receptor and nonreceptor tyrosine kinases is mediated by Ras, a membrane-associated GTPase. Expression of v-Src, a transforming nonreceptor tyrosine kinase, results in Ras activation, and inhibition of Ras function in NIH 3T3 cells suppresses transformation by v-Src, indicating that in these cells Ras-dependent signaling pathways are required for v-Src to exert its biological effects. However, we show here that Ras was not activated in Rat-2 fibroblasts transformed by wild-type v-Src, or in chicken embryo fibroblasts transformed by SRX5, a v-Src mutant with a linker insertion at the major site of autophosphorylation. Expression of a dominant-negative mutant of Ras completely inhibited the ability of v-Src to activate the mitogen-activated protein kinase ERK2, which is downstream of Ras. However, dominant-negative Ras did not suppress transformation by v-Src as judged by a variety of criteria. Thus, v-Src can transform at least some cell types in the absence of Ras activation or Ras-stimulated ERK2 activity, and in these cells activation of Ras-independent signaling pathways must therefore be sufficient for transformation.

Personality change after stroke: some preliminary observations

OBJECTIVES

To describe changes in personality after stroke and effects on carers.

METHODS

A consecutive series of patients was recruited from hospital admissions with stroke. A novel questionnaire was administered to the patients' main carer at nine months after the stroke to determine their perception of the patients' pre-stroke and post-stroke personality. Personality change was identified by changes in these ratings, and associations between personality change and the following variables explored: emotional disorder in patients and carers (measured using the hospital anxiety and depression scale and a structured psychiatric interview), stroke classification (Oxford community stroke classification), residual disability (Barthel index and Nottingham extended activities of daily living scale), and lesion characteristics on computed tomography (CT).

RESULTS

Carers of 35 patients with stroke took part. Reported changes in personality after stroke included: reduced patience and increased frustration (both p<0.0001, t test of difference), reduced confidence, more dissatisfaction, and a less easy going nature (all p<0.005). Occasionally, aspects of personality change were seen as positive by carers. There were relations between greater personality change and interviewer rated patient depression or anxiety (p<0.001) but not when this was self rated; and between personality change and both emotional disorder in carers (p<0.005) and greater disability (p<0.01) but not CT lesion characteristics.

CONCLUSIONS

Carers commonly perceive personality change in stroke patients. This is associated with self rated emotional distress in the carer. More research is needed to understand what carers mean by "personality change" and what factors contribute to the perceived change.

Estrogens influence growth, maturation, and amyloid beta-peptide production in neuroblastoma cells and in a beta-APP transfected kidney 293 cell line

During development in vivo and in vitro, estrogens: a) increase brain excitability, particularly in limbic structures; b) are responsible for the maturation and cyclicity of limbic-hypothalamic interrelations; c) enhance myelinogenesis; and d) may act with NGF to stimulate neurite formation. In senescence, estrogen administration would improve memory in postmenopausal women. The absence or low levels of estrogens after menopause would increase prevalence of Alzheimer's dementia (AD) more in women than men, irrespective of age or ethnicity. In the present study, addition of 17-beta estradiol to cultured human neuroblastoma cells affected growth slightly, but stimulated cell maturation as shown by increased tyrosine hydroxylase activity. The extracellular deposition in brain tissue and around blood vessels of the amyloid beta-peptide (A beta), a 4.3 kD fragment of the larger integral membrane protein, beta-amyloid precursor protein (beta-APP), is considered an important characteristic of AD. We investigated whether 17-beta estradiol may influence the formation of the A beta (thus the abnormal accumulation of amyloid proteins) in neuroblastoma cells and in a beta-APP transfected human kidney 293 cell line. Two doses of 17 beta-estradiol were added to the cultures of both cell lines. Cells were grown until confluence, metabolically labeled with 35S-methionine, immunoprecipitated with the rabbit antiserum R1282, gel electrophoresed and autoradiographed in order to compare levels of A beta under the different estradiol concentrations. While in neuroblastoma cells, levels of A beta were only slightly reduced after estradiol and a dose-effect relationship with the hormone could not be demonstrated, in the 293 cells, A beta band intensity decreased as concentration of estradiol increased. These data support the role of estrogen in normal and abnormal brain metabolism and suggest potential hormonal interventions which may reduce or prevent the formation of amyloid deposits occur in AD.

Effects of introducing an integrated care pathway in an acute stroke unit

BACKGROUND AND PURPOSE

integrated care pathways are often implemented to guide acute stroke therapy and improve organisation of care, but there is not sufficient evidence to support their routine use. We sought to evaluate the effects of introducing an integrated care pathway for acute stroke.

METHODS

we performed a before-and-after study. The 'before' (control) group comprised 154 consecutive stroke patients admitted to the acute stroke unit over a 9-month period. The 'after' (intervention) group comprised 197 consecutive patients admitted to the same unit over a 9-month period in the year after the introduction of the integrated care pathway. Effectiveness was assessed with a variety of measures: quality of documentation; process of care; occurrence of complications; death and discharge destination. Results were adjusted for case mix using a validated model.

RESULTS

the baseline characteristics of the two groups were similar, although there were more total anterior circulation strokes (29% versus 18%, P = 0.005) and fewer partial anterior circulation strokes (30% versus 42% P = 0.04) in the intervention group. In the intervention group, we found that urinary tract infections were significantly less frequent (OR 0.37, CI 0.15-10.91) and the quality of several aspects of care (e.g. CT scanning < 48 hours) and documentation were significantly better. However, there were no significant differences in deaths, discharge destination, or length of stay between the two groups.

CONCLUSION

this before-and-after study has provided further evidence that introducing an integrated care pathway for acute stroke may improve the quality of documentation and process of care, and reduce the risk of certain post-stroke complications.

Reproducibility of Tl-201 and Tc-99m sestamibi gated myocardial perfusion SPECT measurement of myocardial function

BACKGROUND

We compared the reproducibility of thallium 201 and technetium 99m sestamibi (MIBI) gated single photon emission computed tomography (SPECT) measurement of myocardial function using the Germano algorithm (J Nucl Med 1995;36:2138-47).

METHODS AND RESULTS

Gated SPECT acquisition was repeated in the same position in 30 patients who received Tl-201 and in 26 who received Tc-99m-MIBI. The quantification of end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF) on Tl-201 and Tc-99m-MIBI gated SPECT was processed independently with Cedars-Sinai QGS (Quantitative Gated SPECT) software. The reproducibility of the measurement of ventricular function on Tl-201 gated SPECT was compared with that of Tc-99m-MIBI gated SPECT. Correlation between the 2 measurements for volumes and EF was excellent for the repeated gated SPECT studies of Tl-201 (r = 0.928 to 0.986, P <.05) and Tc-99m-MIBI (r = 0.979 to 0.997, P <.05). However, Bland-Altman analysis revealed the 95% limits of agreement (2 SDs) for volumes and EF were narrower by repeated Tc-99m-MIBI gated SPECT (EDV 14.1 mL, ESV 9.4 mL, EF 5.5%) than by repeated Tl-201 gated SPECT (EDV 24.1 mL, ESV 18.6 mL, EF 10.3%). The root-mean-square values of the coefficient of variation for volumes and EF were smaller by repeated Tc-99m-MIBI gated SPECT (EDV 2.1 mL, ESV 2.7 mL, EF 2.3%) than by repeated Tl-201 gated SPECT (EDV 3.2 mL, ESV 3.5 mL, EF 5.2%).

CONCLUSIONS

QGS provides an excellent correlation between repeated gated SPECT with Tl-201 and Tc-99m-MIBI. However, Tc-99m-MIBI provides more reproducible volumes and EF than Tl-201. Tc-99m-MIBI gated SPECT is the preferable method for the clinical monitoring of ventricular function.

Does cognitive impairment affect rehabilitation outcome?

OBJECTIVES

To assess how cognitive impairment affects rehabilitation outcomes and to determine whether individual benefit regardless of cognition.

DESIGN

Prospective open observational study.

SETTING

Two rehabilitation wards admitting older adults after admissions with medical or surgical problems.

PARTICIPANTS

Two hundred forty-one individuals admitted to two rehabilitation wards, 144 female, mean age 84.4 ± 7.3 (range: 59-103).

MEASUREMENTS

The Mini-Mental State Examination (MMSE) was administered, and participants were categorized into four groups: cognitively intact (MMSE score: 27-30), mildly impaired (MMSE score: 21-26), moderately impaired (MMSE score: 11-20), and severely impaired (MMSE score: 0-10). Barthel activity of daily living score was calculated on admission, at 2 and 6 weeks (if appropriate), and at discharge to assess level of independence and improvement or deterioration in function. Information relating to mortality, discharge destination, and length of stay was also collected.

RESULTS

After adjusting for comorbidities and age, all four groups showed improvement in Barthel score from admission to discharge. This improvement was highly significant (P = .005) in participants with normal cognition and mild to moderate impairment. Severely impaired participants also made significant improvement (P = .01). Length of stay was significantly longer for participants with lower cognitive scores. Discharge of 50% of participants occurred by 26, 28, 38, and 47 days for Groups 1 to 4, respectively (P = .001). Higher rates of institutionalization and mortality (P = .02) were associated with lower MMSE score.

CONCLUSION

All participants improved functionally regardless of cognition. Likelihood of institutionalization, mortality, length of stay, and adverse incidents was higher with lower MMSE scores.

Assessing dynamic cerebral autoregulation after stroke using a novel technique of combining transcranial Doppler ultrasonography and rhythmic handgrip

OBJECTIVES

Dynamic cerebral autoregulation (CA) is impaired after stroke. Methods employed to assess this phenomenon usually involve deliberate alterations in blood pressure (BP) by physical means. We performed a pilot study to assess dynamic CA in acute stroke patients using a novel technique of combining transcranial Doppler (TCD) ultrasonography with rhythmic handgrip.

METHODS

Ten patients with ischaemic stroke in the middle cerebral artery (MCA) territory were studied. We performed continuous recordings of bilateral MCA velocities and used rhythmic handgrip to induce BP oscillations. Changes in autoregulation were indicated by changes in phase shift and gain of MCA velocity in relation to BP. Patients were examined at <7 days, 6 weeks, and 3 months after stroke.

RESULTS

There were no significant differences in phase shift or gain between the affected and unaffected cerebral hemispheres. Combining the results from both hemispheres, there was a trend of increasing phase shift (P=0.04) and decreasing gain (P=0.24) over the first three months after stroke, indicating improving CA. Rhythmic handgrip produced an average percentage change in BP (peak-to-trough) of 10% around the mean, and the frequency of the induced BP oscillations was very similar to that of the rhythmic handgrip.

CONCLUSIONS

Combining TCD with rhythmic handgrip appeared to be a useful technique for assessing dynamic CA and it deserves further studies. In this pilot study, there was some evidence that CA might improve up to 3 months after ischaemic stroke.

Circadian infusion of floxuridine in patients with metastatic renal cell carcinoma

A total of 42 patients with metastatic renal cell carcinoma received floxuridine infusion for 14 days at monthly intervals. The drug was delivered via an external programmable pump on a time-modified or circadian schedule; the highest dose of 68% was given between 3 and 9 p.m. Of the 42 patients 25 (60%) had undergone prior nephrectomy. Of the 40 evaluable patients 4 (10%, 95% confidential interval 3 to 24%) achieved a partial response: 3 of the 4 had undergone prior nephrectomy, while 1 had undergone renal angioinfarction. Another 4 patients (10%) had responses at metastatic sites but no response in the primary kidney tumor. The median duration of response for these 2 groups of patients was 65 and 27 weeks, respectively, and the most responsive site was the lungs. The treatment was generally well tolerated and could be administered on an outpatient basis. Our study confirms the limited but definite activity of floxuridine infused on a circadian schedule in patients with metastatic renal cell carcinoma. We observed responses in metastasis equally in patients with or without prior nephrectomy.

Aspirin resistance is more common in lacunar strokes than embolic strokes and is related to stroke severity

The aim of this study was to investigate the relationship between aspirin resistance, ischaemic stroke subtype, stroke severity, and inflammatory cytokines. Aspirin resistance was assessed by thrombelastography in 45 people with ischaemic stroke and 25 controls. Plasma interleukin (IL)-6 was measured. Stroke severity was assessed using the modified Rankin scale and National Institute of Health Stroke Score within 72 h of stroke. Aspirin resistance was more common in the stroke than the control group (67% versus 40%, P=0.028), and within the stroke group the aspirin-resistant group had a higher Rankin score (4.0 versus 2.0, P=0.013). Aspirin resistance was greater in lacunar than embolic strokes (platelet activation 79% versus 59%, P=0.020). The stroke aspirin-resistant group had higher levels of IL-6 than the stroke aspirin-sensitive group (2.4+/-1 versus 1.8+/-0.9 ng/mL, P=0.037). Using multivariate analysis, we examined the interrelationships between aspirin resistance, IL-6, and stroke severity. These analyses showed that IL-6 was independently associated with stroke severity as the outcome (B=3.738, P=0.036), and aspirin resistance was independently associated with IL-6 (B=0.765, P=0.005) as the outcome. In conclusion, aspirin resistance is related to stroke severity and aspirin resistance is more common in lacunar strokes than embolic strokes.