Tissue plasminogen activator for acute ischemic stroke: calculation of dose based on estimated patient weight can increase the risk of cerebral bleeding

The accuracy of total body weight estimation in adults - A systematic review and meta-analysis

BACKGROUND

Weight estimation is required in adult patients when weight-based medication must be administered during emergency care, as measuring weight is often impossible. Inaccurate estimations may lead to inaccurate drug doses, which may cause patient harm. Little is known about the relative accuracy of different methods of weight estimation that could be used during resuscitative care. The aim of this study was to evaluate the performance and suitability of existing weight estimation methods for use in adult emergency care.

METHODS

A systematic literature search was performed for suitable articles that studied the accuracy of weight estimation systems in adults. The study characteristics, the quality of the studies, the weight estimation methods evaluated, the accuracy data, and any information on the ease-of-use of the method were extracted and evaluated.

RESULTS

A total of 95 studies were included, in which 27 different methods of total body weight estimation were described, with 42 studies included in the meta-analysis. The most accurate methods, determined from the pooled estimates of accuracy (the percentage of estimates within 10% of true weight, with 95% confidence intervals) were 3-D camera estimates (88.8% (85.8 to 91.8%)), patient self-estimates (88.7% (87.7 to 89.7%)), the Lorenz method (77.5% (76.4 to 78.6%)) and family estimates (75.0% (71.5 to 78.6%)). However, no method was without significant potential limitations to use during emergency care.

CONCLUSION

Patient self-estimations of weight were generally very accurate and should be the method of choice during emergency care, when possible. However, since alternative estimation methods must be available when confused, or otherwise incapacitated, patients are unable to provide an estimate, alternative strategies of weight estimation should also be available.

Thrombolysis related symptomatic intracranial hemorrhage in estimated versus measured body weight

BACKGROUND AND AIM

In acute ischemic stroke, under- or overestimation of body weight can lead to dosing errors of recombinant tissue plasminogen activator with consequent reduced efficacy or increased risk of hemorrhagic complications. Measurement of body weight is more accurate than estimation of body weight but potentially leads to longer door-to-needle times. Our aim was to assess if weight modality (estimation of body weight versus measurement of body weight) is associated with (i) symptomatic intracranial hemorrhage rate, (ii) clinical outcome, and (iii) door-to-needle times.

METHODS

Consecutive patients treated with intravenous thrombolysis between 2009 and 2016 from 14 hospitals were included. Baseline characteristics and outcome parameters were retrieved from medical records. We defined symptomatic intracranial hemorrhage according to the European Cooperative Acute Stroke Study (ECASS)-III definition and clinical outcome was assessed with the modified Rankin Scale. The association of weight modality and outcome parameters was estimated with regression analyses.

RESULTS

A total of 4801 patients were included. Five hospitals used measurement of body weight (n = 1753), six hospitals used estimation of body weight (n = 2325), and three hospitals (n = 723) changed from estimation of body weight to measurement of body weight during the study period. In 2048 of the patients (43%), measurement of body weight was used and in 2753 (57%), estimation of body weight. In the measurement of body weight group, an inbuilt weighing bed was used in 1094 patients (53%) and a patient lift scale in 954 patients (47%). In the estimation of body weight group, policy regarding estimation was similar. Estimation of body weight was not associated with increased symptomatic intracranial hemorrhage risk (adjusted odds ratio = 1.16; 95% confidence interval 0.83-1.62) or favorable outcome (adjusted odds ratio = 0.99; 95% confidence interval 0.82-1.21), but it was significantly associated with longer door-to-needle times compared to measurement of body weight using an inbuilt weighing bed (adjusted B = 3.57; 95% confidence interval 1.33-5.80) and shorter door-to-needle times compared to measurement of body weight using a patient lift scale (-3.96; 95% confidence interval -6.38 to -1.53).

CONCLUSION

We did not find evidence that weight modality (estimation of body weight versus measurement of body weight) to determine recombinant tissue plasminogen activator dose in intravenous thrombolysis eligible patients is associated with symptomatic intracranial hemorrhage or clinical outcome. We did find that estimation of body weight leads to longer door-to-needle times compared to measurement of body weight using an inbuilt weighing bed and to shorter door-to-needle times compared to measurement of body weight using a patient lift scale.

Different doses of tenecteplase vs alteplase in thrombolysis therapy of acute ischemic stroke: evidence from randomized controlled trials

Background

Recent studies showed inconsistent results of tenecteplase vs alteplase for acute ischemic stroke (AIS) with safety and efficacy.

Methods

A meta-analysis was performed to explore the value of tenecteplase and alteplase in AIS treatment. Medline, Embase, and Cochrane Library from January 2001 to April 2018 were searched for randomized controlled trials (RCTs) with tenecteplase vs alteplase for AIS.

Results

The primary outcomes were early neurological improvement at 24 h and functional outcome at 3 months. We pooled 1,390 patients from four RCTs. Tenecteplase showed a significant early neurological improvement (P=0.035) compared with alteplase. In addition, tenecteplase showed a neutral effect on excellent outcome (P=0.309), good functional outcome (P=0.275), and recanalization (P=0.3). No significant differences in safety outcomes were demonstrated. In subgroup analysis, 0.25 mg/kg dose of tenecteplase showed a significantly increased early neurological improvement (P<0.001). In serious stroke at baseline (National Institutes of Health Stroke Scale [NIHSS] >12) subgroup, tenecteplase showed a dramatic early neurological improvement (P=0.002) and low risks of any intracranial hemorrhage (ICH) (P=0.027).

Conclusion

Tenecteplase provided better early neurological improvement than alteplase. The 0.25 mg/kg dose of tenecteplase subgroup specially showed better early neurological improvement and lower any ICH tendency than that of alteplase. In addition, in serious stroke at baseline subgroup, tenecteplase showed a lower risk of any ICH.

Efficacy and safety of low dose alteplase for intravenous thrombolysis in Asian stroke patients: a meta-analysis

Whether low dose alteplase is comparable to standard dose in efficacy and safety for intravenous thrombolysis (IVT) in Asian stroke patients remains unverified. PubMed, EMBASE, and Cochrane Library Database from the beginning to June 30, 2017 were searched. IVT efficacy was measured by favorable outcome (modified Rankin Scale scores of 0–1) at 3 months, and safety measured by mortality within 3 months and symptomatic intracerebral hemorrhage (SICH). Pooled estimates were conducted using fixed- or random-effects model depending on heterogeneity. For SICH, studies were pooled separately according to different definitions. Twelve studies involving 7,905 participants were included. No association was found between alteplase dose and favorable outcome (OR = 0.94, 95% CI 0.78–1.14, P = 0.5; heterogeneity: P_hetero = 0.01, I² = 57.3%) and mortality (OR = 0.87, 95% CI 0.74–1.02, P = 0.08; P_hetero = 0.83, I² = 0) using random- and fixed-effects models, respectively. Low dose alteplase was associated with lower SICH as defined by the National Institute of Neurological Disorders and Stroke study (OR = 0.79, 95% CI 0.64–0.99, P = 0.04; P_hetero = 0.57, I² = 0) using fixed-effects model. Subgroup and sensitivity analysis could change the results significantly. Current limited evidence was insufficient to support the speculation that low dose alteplase was comparable to standard dose in thrombolytic efficacy and safety in Asian stroke patients.

Purification and characterization of a novel fibrinolytic enzyme from Whitmania pigra Whitman

A fibrinolytic enzyme was purified from the dry body of Whitmania pigra Whitman. The fibrinolytic enzyme was purified to homogeneity with a yield of 0.003% and a purification of 630.7 fold. The molecular weight of the enzyme was estimated to be 26.7 kDa by reduced sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme was tested by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) and it showed that the enzyme was a novel fibrinolytic enzyme. The optimal pH and temperature of the enzyme were 8.5 and 55°C, respectively. Enzyme activity was enhanced by Na⁺, Mg^2+, and K⁺. On the contrary, the proteolytic activity was significantly inhibited by Mn²⁺, Fe²⁺, Fe³⁺, ethylenediaminetetraacetic acid (EDTA), and ethylenebis(oxyethylenenitrilo)tetraacetic acid (EGTA). Fibrinolytic and fibrinogenolytic assays showed that the enzyme preferentially hydrolyzed fibrinogen Aα-chains, followed by Bβ- and γ-chains. The α-, β-, and γ-γ-chains of fibrin were also degraded by the enzyme.