Elevated C-reactive protein increases diagnostic accuracy of algorithm-defined stroke-associated pneumonia in afebrile patients.

BACKGROUND AND AIM: Pyrexia-dependent clinical algorithms may under or overdiagnose stroke-associated pneumonia. This study investigates whether inclusion of elevated C-reactive protein as a criterion improves diagnosis. METHODS: The contribution of C-reactive protein ≥30 mg/l as an additional criterion to a Centers for Disease Control and Prevention-based algorithm incorporating pyrexia with chest signs and leukocytosis and/or chest infiltrates to diagnose stroke-associated pneumonia was assessed in 1088 acute stroke patients from 37 UK stroke units. The sensitivity, specificity, and positive predictive value of different approaches were assessed using adjudicated stroke-associated pneumonia as the reference standard. RESULTS: Adding elevated C-reactive protein to all algorithm criteria did not increase diagnostic accuracy compared with the algorithm alone against adjudicated stroke-associated pneumonia (sensitivity 0.74 (95% CI 0.65-0.81) versus 0.72 (95% CI 0.64-0.80), specificity 0.97 (95% CI 0.96-0.98) for both; kappa 0.70 (95% CI 0.63-0.77) for both). In afebrile patients (n = 965), elevated C-reactive protein with chest and laboratory findings had sensitivity of 0.84 (95% CI 0.67-0.93), specificity of 0.99 (95% CI 0.98-1.00), and kappa 0.80 (95% CI 0.70-0.90). The modified algorithm of pyrexia or elevated C-reactive protein and chest signs with infiltrates or leukocytosis had sensitivity of 0.94 (95% CI 0.87-0.97), specificity of 0.96 (95% CI 0.94-0.97), and kappa of 0.88 (95% CI 0.84-0.93) against adjudicated stroke-associated pneumonia. CONCLUSIONS: An algorithm consisting of pyrexia or C-reactive protein ≥30 mg/l, positive chest signs, leukocytosis, and/or chest infiltrates has high accuracy and can be used to standardize stroke-associated pneumonia diagnosis in clinical or research settings. TRIAL REGISTRATION: http://www.isrctn.com/ISRCTN37118456.

Smoking and common mental disorders in patients with chronic conditions: An analysis of data collected via a web-based screening system.

OBJECTIVE: Smoking is the largest preventable cause of death and disability in the UK and remains pervasive in people with mental disorders and in general hospital patients. We aimed to quantify the prevalence of mental disorders and smoking, examining associations between mental disorders and smoking in patients with chronic physical conditions. METHOD: Data were collected via routine screening systems implemented across two London NHS Foundation Trusts. The prevalence of mental disorder, current smoking, nicotine dependence and wanting help with quitting smoking were quantified, and the relationships between mental disorder and smoking were examined, adjusting for age, gender and physical illness, with multiple regression models. RESULTS: A total of 7878 patients were screened; 23.2% screened positive for probable major depressive disorder, and 18.5% for probable generalised anxiety disorder. Overall, 31.4% and 29.2% of patients with probable major depressive disorder or generalised anxiety disorder respectively were current smokers. Probable major depression and generalised anxiety disorder were associated with 93% and 44% increased odds of being a current smoker respectively. Patients with depressive disorder also reported higher levels of nicotine dependence, and the presence of common mental disorder was not associated with odds of wanting help with quitting smoking. CONCLUSION: Common mental disorder in patients with chronic physical health conditions is a risk factor for markedly increased smoking prevalence and nicotine dependence. A general hospital encounter represents an opportunity to help patients who may benefit from such interventions.

Association between nasogastric tubes, pneumonia, and clinical outcomes in acute stroke patients.

OBJECTIVE: To investigate whether nasogastric tubes (NGTs) increase poststroke pneumonia (PSP), mortality, or poor outcomes in nil-by-mouth acute stroke patients. METHODS: This study analyzed prespecified outcomes of PSP at 14 days and mortality and function measured by the modified Rankin Scale at 90 days in 1,217 nil-by-mouth stroke patients at ≤48 hours of symptom onset in a multicenter randomized controlled trial of preventive antibiotics between April 21, 2008, and May 17, 2014. Generalized mixed models adjusted for age, comorbidities, stroke type and severity, and quality of care were used. No patients were lost to follow-up at 14 days, and 36 (3%) were lost at 90 days. RESULTS: Patients with NGT (298 of 1,217 [24.4%]) had more severe strokes (median NIH Stroke Scale score 17 vs 14, p = 0.0001) and impaired consciousness (39% vs 28%, p = 0.001). NGT did not increase PSP (43 of 298 [14.4%] vs 80 of 790 [10.1%], adjusted odds ratio [OR] 1.26 [95% confidence interval (CI) 0.78-2.03], p = 0.35) or 14- and 90-day mortality (33 of 298 [11.1%] vs 78 of 790 [9.9%], adjusted OR 1.10 [95% CI 0.67-1.78], p = 0.71; and 79 of 298 [26.5%] vs 152 of 790 [19.2%], adjusted OR 0.95 [95% CI 0.67-1.33], p = 0.75, respectively). Ninety-day modified Rankin Scale score distribution was comparable between groups (adjusted OR 1.14 [95% CI 0.87-1.56], p = 0.08). PSP independently increased 90-day mortality (40 of 123 [32.5%] vs 191 of 965 [19.8%], adjusted OR 1.71 [95% CI 1.11-2.65], p = 0.015) and was not prevented by antibiotics in patients with NGT (adjusted OR 1.1 [95% CI 0.89-1.54], p = 0.16). CONCLUSIONS: Early NGT does not increase PSP incidence, mortality, or poor functional outcomes and can be used safely in acute stroke patients.

Comparison of the diagnostic utility of physician-diagnosed with algorithm-defined stroke-associated pneumonia.

OBJECTIVE: Diagnosing stroke-associated pneumonia (SAP) is challenging and may result in inappropriate antibiotic use or confound research outcomes. This study evaluates the diagnostic accuracy of algorithm-defined versus physician-diagnosed SAP in 1088 patients who had dysphagic acute stroke from 37 UK stroke units between 21 April 2008 and 17 May 2014. METHODS: SAP in the first 14 days was diagnosed by a criteria-based algorithm applied to blinded patient data and independently by treating physicians. Patients in whom diagnoses differed were reassigned following blinded adjudication of individual patient records. The sensitivity, specificity, positive predictive value (PPV) and diagnostic OR of algorithmic and physician diagnosis of SAP were assessed using adjudicated SAP as the reference standard. Agreement was assessed using the κ statistic. RESULTS: Physicians diagnosed SAP in 176/1088 (16%) and the algorithm in 123/1088 (11.3%) patients. Diagnosis agreed in 885/1088 (81.3%) patients (κ 0.22 (95% CI 0.14 to 0.29)). On a blinded review, 129/1088 (11.8%) patients were adjudicated as patients with SAP. The algorithm and the physicians had high specificity (97% (95% CI 96% to 98%) and 90% (95% CI 88% to 92%), respectively) but only moderate sensitivity (72% (95% CI 64% to 80%) and 65% (95% CI 56% to 73%), respectively) in diagnosing SAP. The algorithm showed better PPV (76% (95% CI 67% to 83%) vs 48% (95% CI 40% to 55%)), diagnostic OR (80 (95% CI 42 to 136) vs 18 (95% CI 12 to 27)) and agreement (κ 0.70 (95% CI 0.63 to 0.78) vs 0.48 (95% CI 0.41 to 0.54)) than physician diagnosis with adjudicated SAP. CONCLUSIONS: Algorithm-based approaches can standardise SAP diagnosis for clinical practice and research. TRIAL REGISTRATION NUMBER: ISRCTN37118456; Post-results.

The impact of early specialist management on outcomes of patients with in-hospital stroke.

Delays in treatment of in-hospital stroke (IHS) adversely affect patient outcomes. We hypothesised that early referral and specialist management of IHS patients will improve outcomes at 90 days. Baseline characteristics, assessment delays, thrombolysis eligibility, 90-day functional outcomes and all-cause mortality were compared between IHS patients referred for specialist stroke management within 3 hours of symptom onset (early referrals) and later referrals. Patients were identified from a prospective stroke registry between January 2009 and December 2010. Inclusion criteria were primary admission with a non-stroke diagnosis, onset of new neurological deficits after admission and early ischaemic changes on CT or MR imaging. Eighty four (4.6%) of 1836 stroke patients had IHS (mean age 74 year; 51% male, median NIHSS score 10). There were no significant differences in baseline characteristics between 53 (63%) early and 31 (37%) late referrals. Thrombolysis was performed in 29 (76%) of the 37/78 (47%) potentially eligible patients; 7 patients were excluded because specialist referral was delayed beyond 4.5 hours despite symptom recognition within 3 hours of onset. Early referral improved functional outcomes (modified Rankin Scale 0-2 at 90 days 40% v 7%, p = 0.001) and was an independent predictor of mRS 0-2 at 90 days after adjusting for age, pre-morbid function, primary cause for hospital admission and stroke severity [OR 1.13 (95% C.I.  = 1.10-1.27), p = 0.002]. Early referral and specialist management of IHS patients that includes thrombolysis is associated with better functional outcomes at 90 days.

Health professionals' knowledge of driving restrictions following stroke and TIA: experience from a hyperacute stroke centre.

BACKGROUND AND PURPOSE: Assessment of fitness to drive (FTD) is important after stroke or transient ischaemic attack (TIA) to ensure that neither patients nor public are at risk. This is particularly important in patients with TIAs or minor stroke as many are discharged directly from emergency departments by a range of health professionals. We assessed stroke-related FTD knowledge among physicians' and allied health professionals' (AHPs) treating patients with stroke at a hyperacute stroke centre. METHODS: Knowledge of FTD restrictions following a stroke or TIA for domestic and commercial use was assessed in 195 physicians and 45 AHPs using a multiple-choice questionnaire between January and December 2009. The effect of discipline, seniority, previous instruction in FTD restrictions and experience in stroke medicine on FTD was assessed. RESULTS: The correct driving restriction following stroke with domestic and commercial license was known to 29% and 73% of physicians, respectively. For AHPs, these figures were 36% and 20%. For TIA with domestic and commercial license, this was 37% and 43% for physicians, and 44% and 11% for AHPs. 25% of physicians and 11% of AHPs believed that no driving restrictions applied after a TIA. The correct office for reporting FTD was known to 180 (92%) doctors and 31 (69%) AHPs (p=0.0001); 160 (82%) physicians and 27 (60%) AHPs correctly identified that reporting was the patients' responsibility (p=0.001). FTD knowledge correlated with post in stroke (OR 3.2 (95% CI 1.6 to 6.2, p=0.001)) but not with seniority or previous FTD education. CONCLUSIONS: Health professionals providing stroke care showed limited knowledge of FTD regulations after minor stroke or TIA. Imparting accurate information on driving restrictions is an important but neglected part of stroke management.

Influence of age on thrombolysis outcome in wake-up stroke.

BACKGROUND AND PURPOSE: Thrombolysis in patients >80 years remains controversial; we hypothesized that >80-year-old patients with wake-up ischemic stroke (WUIS) will benefit from thrombolysis despite risks because of poor outcomes with no treatment. METHODS: The study included 68 thrombolysed patients with WUIS (33 [48%] >80 years), 54 nonthrombolysed patients with WUIS (21 [39%] >80 years), and 117 patients (>80 years old) thrombolysed within 4.5 hours of symptom onset (reference group). Mortality and modified Rankin Scale (mRS) were assessed at 90 days. RESULTS: Baseline characteristics of thrombolysed and nonthrombolysed >80 and ≤80-year-old patients with WUIS were comparable. Thrombolysis outcomes in >80-year-old patients with WUIS were better than in nonthrombolysed >80-year-old patients with WUIS (90-day mortality: 24% versus 47%, P=0.034; mRS 0-2: 30% versus 5%, P=0.023; mRS 0-1: 15% versus 5%, P=0.24) and comparable with thrombolysed ≤80-year-old patients with WUIS. Thrombolysis was associated with odds ratio 0.27 (95% confidence interval, 0.05-0.97) for mortality and odds ratio 28.6 (95% confidence interval, 1.8-448) for mRS 0 to 2 at 90 days in >80-year-old patients with WUIS after adjusting for stroke severity and risk factors. CONCLUSIONS: Thrombolysis may be associated with greater benefit in >80-year-old patients with WUIS but a selection bias favoring thrombolysis in those most likely to benefit may significantly reduce interpretability of these findings.

A case-controlled comparison of thrombolysis outcomes between wake-up and known time of onset ischemic stroke patients.

BACKGROUND AND PURPOSE: Wake-up ischemic stroke (WUIS) patients are not thrombolysed even if they meet other criteria for treatment. We hypothesized that patients with WUIS showing no or early ischemic changes on brain imaging will have thrombolysis outcomes comparable with those with known time of symptom onset. METHODS: Consecutive sampling of a prospective registry of patients with stroke between January 2009 and December 2010 identified 394 thrombolysed patients meeting predefined inclusion criteria, 326 presenting within 0 to 4.5 hours of symptom onset (Reference Group) and 68 WUIS patients. Inclusion criteria were last seen normal<12 hours or >4.5 hours (WUIS) or presented <4.5 hours (Reference Group), had National Institutes of Health Stroke Scale score ≥5, and no or early ischemic changes on imaging at presentation. The primary outcome measure was the modified Rankin Scale of 0 to 2 at 90 days measured by trained assessors blinded to patient grouping. Other outcome measures were symptomatic intracerebral hemorrhage, modified Rankin Scale 0 to 1, and mortality at 90 days. RESULTS: The groups were comparable for mean age (72.8 versus 73.9 years; P=0.58) and baseline median National Institutes of Health Stroke Scale score (median 13 versus 12; P=0.34). The proportions of patients with modified Rankin Scale 0 to 2 (38% versus 37%; P=0.89) and modified Rankin Scale 0 to 1 (24% versus 16%; P=0.18) at 90 days, any ICH (20% versus 22%; P=0.42) and symptomatic intracerebral hemorrhage (3.4% versus 2.9%; P=1.0) were comparable after adjusting for age, stroke severity, and imaging changes. Only 9/394 (2%) patients were lost to follow-up. CONCLUSIONS: Thrombolysis in selected patients with WUIS is feasible, and its outcomes are comparable with those thrombolysed with 0 to 4.5 hours.

An observational study of thrombolysis outcomes in wake-up ischemic stroke patients.

BACKGROUND AND PURPOSE: Wake-up ischemic stroke (WUIS) patients are not eligible for thrombolysis; the a priori hypothesis was that thrombolysis of selected WUIS patients who meet clinical and imaging criteria for treatment is associated with better outcomes. METHODS: The sample consisted of consecutive WUIS patients who fulfilled predefined criteria: (1) were last seen normal >4.5 hours and <12 hours before presentation; (2) National Institute of Health Stroke Scale score ≥ 5; (3) No or early ischemic changes <1/3 middle cerebral artery territory on computed tomography imaging; (4) No absolute contraindications to thrombolysis. The primary outcome measure was the modified Rankin Scale of 0 to 2 at 90 days. Other outcome measures were mortality and symptomatic intracerebral hemorrhage. RESULTS: WUIS patients constituted 10.5% (193/1836) of all stroke admissions. Inclusion criteria were fulfilled by 122 (63%) patients, of whom 68 (56%) were thrombolysed. Thrombolysed and nonthrombolysed patients were comparable for baseline characteristics, but the median baseline National Institute of Health Stroke Scale score was higher in thrombolysed patients (9 versus 11.5; P=0.034). There was no difference in modified Rankin Scale 0 to 2 (25 [37%] versus 14 [26%]; P=0.346), death (10 [15%] versus 14 [26%]; P=0.122), and symptomatic intracerebral hemorrhage (2 versus 0; P=0.204) between thrombolysed and nonthrombolysed patients. After adjusting for age, sex, and baseline National Institute of Health Stroke Scale score thrombolysis was associated with odds ratio of 5.2 (95% confidence interval 1.3-20.3), P=0.017 for modified Rankin Scale 0 to 2 at 90 days and odds ratio of 0.09 (95% confidence interval 0.02-0.44), P=0.003 for death. CONCLUSIONS: Thrombolysis in selected WUIS patients is feasible and may have potential of benefit.

Transcranial Doppler and cerebral augmentation in acute ischemic stroke.

BACKGROUND: Collateral flow augmentation using partial aortic occlusion may improve cerebral perfusion in acute stroke. We assessed the effect of partial aortic occlusion on arterial flow velocities of acute stroke patients. METHODS: Patients with neurological deficits following thrombolysis were treated with partial aortic occlusion. Transcranial Doppler ultrasound (TCD) was used to measure arterial flow velocities at baseline, before and during balloon inflation. The augmented mean flow velocity (MFV), peak systolic velocity (PSV), and end diastolic velocity flow percentages (aMFV%, aPSV%, aEDV%) were calculated and compared based on outcome. RESULTS: Of 11 patients, 3 did not have a temporal window and thus were excluded from our analysis. Six of the remaining 8 patients had middle cerebral artery (MCA) occlusions; the final 2 had terminal internal carotid artery (TICA) occlusions. Three of these 8 patients had good outcome at 90 days (mRS < 3). Before intra-aortic balloon inflation (IABI), the mean affected artery MFV was 23 ± 11 cm/s; during the procedure it was 26 ± 12 cm/s (P = .2). Mean affected artery PSV at baseline and during balloon inflation were 37 ± 16 and 46 ± 23, respectively (P = .1). Mean augmented affected artery MFV% in patients with good long-term outcome was 65.4 ± 46, while the result in those with poor outcome was -3.7 ± 21 (P = .03). Three patients developed anterior cross-filling, and of these 2 had good long-term outcome. CONCLUSION: TCD monitoring of patients treated with IABI may help in predicting outcome in this novel device.

Safety and clinical outcome of thrombolysis in ischaemic stroke using a perfusion CT mismatch between 3 and 6 hours.

OBJECTIVE: It may be possible to thrombolyse ischaemic stroke (IS) patients up to 6 h by using penumbral imaging. We investigated whether a perfusion CT (CTP) mismatch can help to select patients for thrombolysis up to 6 h. METHODS: A cohort of 254 thrombolysed IS patients was studied. 174 (69%) were thrombolysed at 0-3 h by using non-contrast CT (NCCT), and 80 (31%) at 3-6 h (35 at 3-4.5 h and 45 at 4.5-6 h) by using CTP mismatch criteria. Symptomatic intracerebral haemorrhage (SICH), the mortality and the modified Rankin Score (mRS) were assessed at 3 months. Independent determinants of outcome in patients thrombolysed between 3 and 6 h were identified. RESULTS: The baseline characteristics were comparable in the two groups. There were no differences in SICH (3% v 4%, p = 0.71), any ICH (7% v 9%, p = 0.61), or mortality (16% v 9%, p = 0.15) or mRS 0-2 at 3 months (55% v 54%, p = 0.96) between patients thrombolysed at 0-3 h (NCCT only) or at 3-6 h (CTP mismatch). There were no significant differences in outcome between patients thrombolysed at 3-4.5 h or 4.5-6 h. The NIHSS score was the only independent determinant of a mRS of 0-2 at 3 months (OR 0.89, 95% CI 0.82-0.97, p = 0.007) in patients treated using CTP mismatch criteria beyond 3 h. CONCLUSIONS: The use of a CTP mismatch model may help to guide thrombolysis decisions up to 6 h after IS onset.

Screening for right-to-left shunts with contrast transcranial Doppler in hereditary hemorrhagic telangiectasia.

BACKGROUND AND PURPOSE: Contrast transthoracic echocardiography (TTCE) is used to screen hereditary hemorrhagic telangiectasia (HHT) patients for right-to-left shunts (RLS) associated with increased stroke risk. We hypothesized that contrast transcranial Doppler (TCDc), shown to be highly sensitive for detecting RLS in patent foramen ovale, will be as comparable to TTCE for screening HHT patients. METHODS: We compared TTCE and TCDc for detecting RLS in 12 patients with HHT who also underwent CT pulmonary studies to determine pulmonary arteriovenous malformation (PAVM) presence. The sensitivity and specificity of TTCE and TCDc in detecting PAVM were determined and the agreement between TTCE and TCDc in detecting RLS was assessed. RESULTS: Both TTCE and TCDc had 100% sensitivity in detecting underlying PAVM; the specificity was 25% and 38%, respectively. The agreement in detecting RLS between TTCE and TCD was high (κ=0.76). TCD was well-tolerated with no immediate adverse or embolic events over the next 3 months. CONCLUSIONS: TCDc offers a simple office-based alternative to TTCE for screening RLS associated with PAVM in HHT patients.

Blood pressure management in acute intracerebral haemorrhage guidelines are poorly implemented in clinical practice.

BACKGROUND: Optimal management of blood pressure (BP) in spontaneous intracerebral haemorrhage (ICH) is controversial. We assessed adherence to BP guidelines and its management in ICH in a tertiary Canadian Stroke Centre. METHODS: We conducted a retrospective analysis of 142 CT confirmed primary ICH patients admitted within 24h of symptoms between 2005 and 2006. Initial practice with respect to BP control was reviewed and compared with current guidelines. This retrospective sample was compared with a prospective cohort participating in a BP lowering trial for the attainment of pre-defined BP targets. We also assessed the effect of BP treatment on hematoma expansion and mortality. RESULTS: Blood pressure treatment orders were established in 73% of the 142 patients (median age 71 years, 61% male). Only 26% of patients had target orders as advised in the current AHA guidelines. Only 54% achieved BP targets as compared with 83% of the prospective cohort within 1h. Patients with established BP orders were more likely to have repeat brain imaging (70.2%) than those without (39.5%; p=0.001 Mortality rates were 29.8% and 47.4% in those with and without BP targets respectively (p=0.051). CONCLUSIONS: Management of BP varies considerably and there appears to be little adherence to recommended guidelines. Targets are achieved more rapidly if a BP treatment protocol is utilized.

Emergency department or general practitioner following transient ischaemic attack? A comparison of patient behaviour and speed of assessment in England and Canada.

OBJECTIVE: Many patients present late after a transient ischaemic attack (TIA). This delays intervention and may partly depend on where patients first present--emergency department (ED) or general practitioner (GP). Studying this behaviour could improve stroke prevention through better targeting of public education and allocation of resources. METHODS: Patients with TIA or minor stroke referred to neurovascular clinics in the UK and Canada were studied and the delay from onset to first medical presentation, whether at an ED or GP, was measured. Clinical features, timing and place of presentation were compared. RESULTS: Of 666 patients (469 in the UK and 197 in Canada), only 42% presented on the day of the TIA. The majority (77%) of patients presenting to an ED presented on the same day compared with only 11% of those who presented to a GP. GP delays were longer at weekends. Motor or speech symptoms and prolonged duration were associated with presenting early and to an ED. High-risk patients (ABCD2 score 6-7) in Canada were also more likely to go to an ED. Overall, 65% of Canadian patients and 40% of UK patients went to an ED. CONCLUSIONS: Most patients presenting to an ED go urgently, whereas most going to a GP delay, particularly at weekends. Most Canadian patients, particularly those at high risk, go to an ED whereas most UK patients go to a GP. One way to reduce delay, particularly in the UK, would be to direct all patients with TIA to go to an ED rather than to their GP.

Sodium imaging intensity increases with time after human ischemic stroke.

OBJECTIVE: Establishing time of onset is important in acute stroke management. Current imaging modalities do not allow determination of stroke onset time. Although correlations between sodium magnetic resonance imaging signal intensity within ischemic lesions and time of onset have been shown in animal models, the relation to onset time has not been established in human stroke. Utilizing high-quality sodium images, we tested the hypothesis that sodium signal intensity increases with time from symptom onset in human ischemic stroke. METHODS: Twenty-one stroke patients (63 +/- 15 years old) were scanned 4 to 104 hours after symptom onset. Follow-up images were obtained in 10 patients at 23 to 161 hours after onset, yielding a total of 32 time points. A standard stroke imaging protocol was acquired at 1.5 Tesla, followed by sodium magnetic resonance imaging at 4.7 Tesla. Relative sodium signal intensity within each lesion was measured with respect to the contralateral side. RESULTS: The sodium image quality was sufficient to visualize each acute lesion (lesion volume range, 1.7-217cm(3)). Relative sodium signal intensity increased nonlinearly over time after stroke onset. Sodium images acquired within 7 hours (n = 5) demonstrated a relative increase in lesion intensity of 10% or less, whereas the majority beyond 9 hours demonstrated increases of 23% or more, with an eventual leveling at 69 +/- 18%. INTERPRETATION: Increases of sodium signal intensity within the ischemic lesion are related to time after stroke onset. Thus, noninvasive imaging of sodium may be a novel metabolic biomarker related to stroke progression. Ann Neurol 2009;66:55-62.

Hemicraniectomy for massive middle cerebral artery infarction: a review.

Hemicraniectomy and opening underlying dura mater permits the expansion of infarcted, swollen brain outwards, reversing dangerous intracranial pressure elevations and the risk of fatal transtentorial temporal lobe or diencephalic herniation. Recently published randomized controlled trials have proven this procedure a powerful life-saving measure in the setting of malignant middle cerebral artery infarction and allayed concerns that a reduction in mortality is accompanied by an unacceptable increase in patients suffering severe neurological impairments. Appropriate patients are relatively young, in the first five decades of life, suffering infarction of a majority of the middle cerebral artery (MCA) territory in either hemisphere, and decompression should be performed prior to progression to coma or two dilated, fixed pupils. Lethargy combined with midline shift and uncal herniation on neuroimaging is an appropriate trigger to consider and discuss surgical intervention. Families and, when possible, patients themselves, should be informed of the certainty of at least moderate to mild permanent deficits, and the possibility of worse. To be successful decompression must be extensive, targeting a bone flap measuring 14 cm from front to back, and extending 1 to 2 cm lateral to the midline sagittal suture to the floor of the middle cranial fossa at the level of the coronal suture. An augmentation duraplasty is mandatory.

Repeatability of non-invasive measurement of intracerebral pulse wave velocity using transcranial Doppler.

In the present study, the repeatability of three techniques for measuring peripheral PWV (pulse wave velocity) has been studied. A transcranial Doppler provided a wave reading from the middle cerebral artery. Using the transit time between the R-wave of an ECG and the 'foot' of this wave we were able to calculate a PWV (PWV-brain). An ear clip transducer provided a pressure wave reading (PWV-ear). A third pressure reading came from a Finapres transducer on the left middle finger (PWV-finger). The PWV was calculated as distance between two points/transit time of the pulse wave. Eleven volunteers had three sets of readings averaged for each technique taken in two separate sessions. There was good agreement between observers for the mean PWV values, and good agreement for mean results in different sessions. The RC%s (repeatability coefficient percentages) for between-observer repeatability in each session were good and approximately equivalent for PWV-finger (5-7%) and PWV-brain (5-7%). The repeatability of the PWV-ear measurement was less satisfactory (8-18%). The RC% for the same observer between sessions was less good, being 11% for the PWV-finger, 16-17% for PWV-brain and 11-19% for PWV-ear. The RC%s for the inter-session inter-observer measurements were between 10.7-12.1% for the PWV-finger, 14.7-19.5% for PWV-brain and 8.3-15% for PWV-ear. The transit time RC%s were lower in most measurements. The between-observer repeatability of all measures was satisfactory. Owing to the less good repeatability on different occasions, the use of PWV-brain and PWV-ear will depend on the magnitude of differences to be expected.