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The effectiveness of mechanical thrombectomy (MT) in elderly stroke patients remains debated. We aimed to describe outcomes and their predictors in a cohort of patients aged ≥ 85 years treated with MT.
Data from consecutive patients aged ≥ 85 years undergoing MT at two stroke centers between January 2016 and November 2019 were reviewed. Admission National Institutes of Health Stroke Scale (NIHSS), pre-stroke, and 3-month modified Rankin scale (mRS) were collected. Successful recanalization was defined as modified thrombolysis in cerebral ischemia score ≥ 2b. Good outcome was defined as mRS 0–3 or equal to pre-stroke mRS at 3 months.
Of 151 included patients, successful recanalization was achieved in 74.2%. At 3 months, 44.7% of patients had a good outcome and 39% had died. Any intracranial hemorrhage (ICH) and symptomatic ICH occurred in 20.3% and 3.6%, respectively. Logistic regression analysis identiﬁed lower pre-stroke mRS score (adjusted odds ratio [aOR], 0.52; 95% CI, 0.36–0.76), lower admission NIHSS score (aOR, 0.90; 95% CI, 0.83–0.97), successful recanalization (aOR, 3.65; 95% CI, 1.32–10.09), and absence of ICH on follow-up imaging (aOR, 0.42; 95% CI, 0.08–0.75), to be independent predictors of good outcome. Patients with successful recanalization had a higher proportion of good outcome (45.3% vs 34.3%, p = 0.013) and lower mortality at 3 months (35.8% vs 48.6%, p = 0.006) compared to patients with unsuccessful recanalization.
Among patients aged ≥ 85 years, successful recanalization with MT is relatively common and associated with better 3-month outcome and lower mortality than failed recanalization. Attempting to achieve recanalization in elderly patients using MT appears reasonable.
Intravenous thrombolytic therapy (IV) with recombinant tissue-plasminogen activator (alteplase; 0.9 mg/kg over 1h) is beneficial for acute ischaemic stroke patients with potentially disabling neurological deficits, and without contraindications, when started =4.5h of onset. Benefit is time-dependent: among 1000 patients, IVT =3h lessen long-term disability in 178 patients, between 3-4.5h in 66. IVT under 4.5h is associated with an increase in symptomatic haemorrhage, but not an increase in death or severe disability. Based on trial evidence, IVT =3h is strongly endorsed, and between 3-4.5 hours moderately endorsed, by guidelines on 5 continents. Benefit is evident in patients under and over age 80, and in patients with up to moderate, but not extensive (more than 100 cc), early ischaemic changes on initial CT or MRI. IVT is also beneficial for patients =4.5h after onset with substantial salvageable tissue on penumbral CT or MR imaging. Systems of care should be optimized to start IVT =60m, and optimally =30m, after ED arrival. Large-scale trials are needed to further enhance IVT, testing: faster treatment start in mobile stroke units (mobile CT ambulances): fibrinolytic agent and concomitant lytic-enhancing combinations; bridging neuroprotection and collateral enhancement; and the optimal way to combine intravenous thrombolytic therapy and endovascular mechanical thrombectomy.
Endovascular thrombectomy (EVT) with highly effective reperfusion devices is beneficial for: 1) relatively broadly selected acute ischaemic stroke patients with anterior circulation large vessel occlusions (LVOs) who have failed or are ineligible for intravenous fibrinolysis, up to 7 h after onset; and 2) imaging-selected patients with a favorable penumbral profile (small core and substantial salvageable tissue) 6–24h after onset. Among early-presenting patients, benefit is strongly time-dependent; for every 4 m delay in door-to-reperfusion time, 1 of every 100 patients has a worse disability outcome. Based on the trial evidence, EVT is strongly endorsed by guidelines worldwide. Within the first 7h, benefit is evident in patients under and over age 80, and in patients with up to moderate early ischaemic changes on imaging (ASPECTS 6-10). Systems of care should be optimized to deliver likely LVO patients to endovascular-capable stroke centers, and for procedure start (arterial puncture) within 75m, and optimally within 45m, after ED arrival. Large-scale trials are testing: best prehospital recognition and routing protocols: novel device designs to increase reperfusion rates in large and also medium vessel occlusions; bridging neuroprotection and collateral enhancement; potential benefit in patients with large cores; and best concomitant therapies, including sedation mode and post-procedure blood pressure management.
A successful liver transplant requires a number of procedures, including donor hepatectomy, preparation of the donor liver, recipient hepatectomy, and implantation of the liver graft. A midline laparotomy and sternotomy are performed and can be extended using transverse abdominal incisions to maximize surgical access. Preparation of the liver for transplantation is usually performed following a period of efficient cooling in an ice box and transportation to the recipient center. The hepatectomy begins with division of the left triangular ligament, falciform ligament, and lesser omentum before moving to the hilum. The greatest challenge when performing the portal venous anastomosis is the presence of portal vein thrombosis (PVT), which was originally an absolute contraindication to liver transplantation, but is now part of standard practice. Reperfusion of the liver is often the most dangerous part of the transplant procedure, and close communication between surgeon and anesthetist is crucial.
Remote ischaemic pre-conditioning and cardiac ischaemic post-conditioning provide myocardial protection in cardiac surgery. However, these two endogenous strategies have not been directly compared in a clinical setting. The purpose of this study was to compare the efficacy of remote ischaemic pre-conditioning and post-conditioning in providing myocardial protection to children undergoing cardiopulmonary bypass for surgical repair of ventricular septal defect.
We randomly assigned 60 paediatric patients scheduled for surgical correction of congenital ventricular septal defect to the post-conditioning group (n = 20), remote pre-conditioning group (n = 20), or control group (n = 20). Post-conditioning consisted of 30 seconds of ischaemia and 30 seconds of reperfusion achieved by clamping and unclamping the aorta, repeated three times over 3 minutes immediately after cardioplegic arrest. Remote ischaemic pre-conditioning consisted of 5 minutes of lower limb ischaemia followed by 5 minutes of reperfusion using a blood-pressure cuff inflated to a pressure of 200 millimetres of mercury, also repeated three times over 30 minutes. We assayed creatine kinase-MB, troponin I.
Mean age, cardiopulmonary bypass times, and aortic cross-clamp times were matched across groups. Both post-conditioning and remote ischaemic pre-conditioning reduced the peak release of creatine kinase-MB (86.1 plus or minus 24.1 units per litre and 92.8 plus or minus 20.6 units per litre, respectively, versus 111.0 plus or minus 44.6 units per litre in the control, p less than 0.05) and troponin I (0.28 plus or minus 0.10 nanogram per millilitre and 0.26 plus or minus 0.09 nanogram per millilitre, respectively, versus 0.49 plus or minus 0.19 nanogram per millilitre in the control group, p less than 0.05).
Our study demonstrates that ischaemic post-conditioning and remote ischaemic pre-conditioning provide comparable myocardial benefit in children undergoing cold blood cardioplegic arrest.
Timely reperfusion therapy for ST-elevation myocardial infarction (STEMI) is an important determinant of outcome, yet targets for time to treatment are frequently unmet in North America. Prehospital strategies can reduce time to reperfusion. We sought to determine the extent to which emergency medical services (EMS) use these strategies in Canada.
We carried out a cross-sectional survey in 2007 of ground EMS operators in British Columbia, Alberta, Ontario, Quebec and Nova Scotia. We focused on the use of 4 prehospital strategies: 1) 12-lead electrocardiogram (ECG), 2) routine expedited emergency department (ED) transfer of STEMI patients (from a referring ED to a percutaneous coronary intervention [PCI] centre), 3) prehospital bypass (ambulance bypass of local EDs to transport patients directly to PCI centres) and 4) prehospital fibrinolysis.
Ninety-seven ambulance operators were surveyed, representing 15 681 paramedics serving 97% of the combined provincial populations. Of the operators surveyed, 68% (95% confidence interval [CI] 59%–77%) had ambulances equipped with 12-lead ECGs, ranging from 40% in Quebec to 100% in Alberta and Nova Scotia. Overall, 47% (95% CI 46%-48%) of paramedics were trained in ECG acquisition and 40% (95% CI 39%–41%) were trained in ECG interpretation. Only 18% (95% CI 10%–25%) of operators had prehospital bypass protocols; 45% (95% CI 35%–55%) had protocols for expedited ED transfer. Prehospital fibrinolysis was available only in Alberta. All EMS operators in British Columbia, Alberta and Nova Scotia used at least 1 of the 4 prehospital strategies, and one-third of operators in Ontario and Quebec used 0 of 4. In major urban centres, at least 1 of the 3 prehospital strategies 12-lead ECG acquisition, bypass or expedited transfer was used, but there was considerable variation within and across provinces.
The implementation of widely recommended prehospital STEMI strategies varies substantially across the 5 provinces studied, and relatively simple existing technologies, such as prehospital ECGs, are underused in many regions. Substantial improvements in prehospital services and better integration with hospital-based care will be necessary in many regions of Canada if optimal times to reperfusion, and associated outcomes, are to be achieved.
Postconditioning by brief episodes of ischaemia performed just at the time of reperfusion have been shown to reduce the size of infarcts in animal models, and in the clinical setting of percutaneous cardiac intervention. The clinical applicability of postconditioning in cardiac surgery remains to be determined. We investigated the effect of postconditioning on myocardial protection in children undergoing cardiac surgery.
We randomly assigned 40 patients scheduled for surgical correction of congenitally malformed hearts under cold blood cardioplegic arrest to postconditioning or control treatment. Postconditioning was performed by two cycles of 30 seconds ischaemia and 30 seconds reperfusion using aortic reclamping, and declamping started 30 seconds after cardioplegic arrest. We assayed creatine kinase-MB, troponin I, transcardiac release of lactate and neutrophil counts.
The types of procedure, age, bypass and aortic cross-clamping times were similar in both groups. The postoperative peaks of creatine kinase-MB and troponin I were lower after aortic de-clamping in the postconditioned patients compared with their controls (128 ± 48 units per liter as opposed to 199 ± 79 units per liter, p = 0.016, and 0.34 ± 0.21 nanograms per milliliter as opposed to 0.61 ± 0.53 nanograms per milliliter, p = 0.05), with reduced inotropic scores in those submitted to postconditioning compared with their controls (4.8 ± 3.1 versus 2.3 ± 1.5, p = 0.036). Transcardiac release of lactate was reduced in the postconditioned patients compared with their controls (0.10 ± 0.27 as opposed to 0.37 ± 0.43 millimols per liter, p = 0.048). No differences between groups were found for transcardiac neutrophil count during reperfusion (10.8 ± 6.3% for postconditioning versus 14.0 ± 8.7% for controls, p = 0.48).
Our study demonstrates that postconditioning may protect the myocardium of children undergoing cold blood cardioplegic arrest. These data support the need for a larger clinical trial of postconditiong in children undergoing cardiac surgery.
We have previously shown that dietary red palm oil (RPO) supplementation improves functional recovery in hearts subjected to ischaemia–reperfusion. However, little knowledge exists concerning the effects of RPO supplementation of a high-cholesterol diet on ischaemia–reperfusion injury. The signalling mechanisms responsible for RPO's effects in the presence of cholesterol also remain to be elucidated. Therefore, the aim of the present study was to examine the effects of RPO, given with a high-cholesterol diet, on mitogen-activated protein kinase (MAPK) phosphorylation and apoptosis. Long–Evans rats were fed a control diet, a control diet containing 2 % cholesterol, or a control diet containing 2 % cholesterol and 7 g RPO per kg (CRPO) for 5 weeks. Hearts were excised and mounted on an isolated working heart perfusion apparatus. Cardiac function was measured after which hearts were freeze-clamped and used to assess MAPK phosphorylation and to evaluate apoptosis. Cholesterol supplementation caused a poor aortic output (AO) recovery compared with the control group (35·5 (sem 6·2) v. 55·4 (sem 2·5) %), but when RPO was added, the percentage AO increased significantly. The cholesterol group's poor AO was associated with a significant increase in p38-MAPK phosphorylation, whereas the CRPO-supplemented group showed as significant reduction in p38-MAPK phosphorylation when compared with the cholesterol-supplemented group. This significant reduction in p38-MAPK was also associated with reduced apoptosis as indicated by significant reductions in caspase-3 and poly(ADP-ribose) polymerase cleavage.
The prehospital 12-lead electrocardiogram (ECG) has become a standard of care. For the prehospital 12-lead ECG to be useful clinically, however, cardiologists and emergency physicians (EP) must view the test as useful. This study measured physician attitudes about the prehospital 12-lead ECG.
This study tested the hypothesis that physicians had “no opinion” regarding the prehospital 12-lead ECG.
An anonymous survey was conducted to measure EP and cardiologist attitudes toward prehospital 12-lead ECGs. Hypothesis tests against “no opinion” (VAS = 50 mm) were made with 95% confidence intervals (CIs), and intergroup comparisons were made with the Student-t-test.
Seventy-one of 87 (81.6%) surveys were returned. Twenty-five (67.6%) cardiologists responded and 45 (90%) EPs responded. Both groups of physicians viewed prehospital 12-lead ECGs as beneficial (mean = 69 mm; 95% CI = 65–74mm). All physicians perceived that ECGs positively influence preparation of staff (mean = 63 mm; 95% CI = 60–72mm) and that ECGs transmitted to hospitals would be beneficial (mean = 66 mm; 95% CI = 60–72mm). Cardiologists had more favorable opinions than did EPs. The ability of paramedics to interpret ECGs was not seen as important (mean = 50 mm; 95% CI = 43–56mm). The justifiable increase in field time was perceived to be 3.2 minutes (95% CI = 2.7–3.8 minutes), with 23 (32.8%) preferring that it be done on scene, 46 (65.7%) during transport, and one (1.4%) not at all.
Prehospital 12-lead ECGs generally are perceived as worthwhile by cardiologists and EPs. Cardiologists have a higher opinion of the value and utility of field ECGs. Since the reduction in mortality from the 12-lead ECG is small, it is likely that positive physician attitudes are attributable to other factors.
Ischaemia and reperfusion phases represent critical events during liver transplantation. The purpose of this study was to describe morphological alterations of both vascular and parenchymal compartments after ischaemia and reperfusion and to evaluate the possible relationship between morphometric parameters and biochemical/clinical data. Three needle biopsies were drawn from 20 patients who underwent orthotopic liver transplantation. The first biopsy was taken before flushing with preservation solution, and the second and the third to evaluate respectively the effects of cold ischaemia and of warm ischaemia/reperfusion. Biopsies were examined by an image analyser and morphometric parameters related to the liver parenchyma were evaluated. At the second biopsy we observed a decrease of the endothelium volume fraction while the same parameter referred to the sinusoidal lumen achieved a peak value. The hepatocytes showed a lower surface parenchymal/vascular sides ratio. This parameter was reversed at the end of the reperfusion phase; furthermore the third biopsy revealed endothelial swelling and a decreased volume fraction of the sinusoidal lumen. The results quantify the damage to the sinusoidal bed which, as already known, is one of the main targets of cold ischaemia; warm ischaemia and reperfusion accentuate endothelial damage. The end of transplantation is characterised by damage chiefly to parenchymal cells. Hepatocytes show a rearrangement of their surface sides, probably related to the alterations of the sinusoidal bed. In addition, the fluctuations of morphometric parameters during ischaemia/reperfusion correlate positively with biochemical data and clinical course of the patients.
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