The development and evaluation of options for improving future U.K. blood component labelling--outcome of the 2013 U.K. hospital survey

BACKGROUND/OBJECTIVES

U.K. blood component labels have evolved to accommodate a plethora of information. Concern has, however, been expressed that current U.K. labelling is too 'cluttered', detracting from the clarity of critical information. This prompted a holistic review of labelling and available information technology (IT) with the aim of improving the situation.

METHODS/MATERIALS

A survey was circulated requiring U.K. hospital participants to rank each item of information on the label according to its 'criticality' and assess three novel 'future' and one 'transition' prototype labels. Prototypes were based on applicable regulatory standards, best practice guidance, international benchmark data and U.K. expert input. The prototypes support steps towards 'full face' label printing and utilise 2D and quick response (QR) barcodes.

RESULTS

Two-hundred eleven completed surveys were received identifying 110 contributing hospitals with 41% from clinical staff, 37% from transfusion laboratory staff and 22% from transfusion practitioners. There was excellent agreement between the three groups on the critical information, i.e., blood group, expiry date, blood component name, unique donation identification number (DIN) and blood component volume but far less on the other information, especially the various warning messages. Of the 'future' labels, option 3 (closest to the current 'quadrant model') was most popular. Option 1, with its additional inverted section replicating critical information was least popular and prompted significant safety concerns.

CONCLUSION

The prototype labels correctly identified the critical items of information and extensive comments confirmed that this was more prominently and clearly displayed. Laboratory staff commented that the transition label was essential to enable IT systems to be adapted.

Optimising outcome assessment to improve quality and efficiency of stroke trials

Substantial progress has been made in treatment of stroke and much of this has been driven by large scale, multi-centre, randomised controlled trials. Although stroke is a frequent cause of mortality, stroke-related disability and functional decline is of equal or greater concern to patients and carers. Thus, to prove efficacy of an intervention for stroke, we need robust methods of describing recovery. Various functional assessment scales are available, the tool recommended as trial end point by many specialist societies and regulatory authorities is the modified Rankin Scale (mRS). We will use the mRS as exemplar to discuss contemporary research around functional assessment for stroke trials, including recent work around structured assessments, assessor training and end point adjudication panels. We will present an overview and critique of these studies and give examples where strategies to improve mRS assessment are impacting on the quality of stroke clinical trials.

Robotic measurement of arm movements after stroke establishes biomarkers of motor recovery

BACKGROUND AND PURPOSE

Because robotic devices record the kinematics and kinetics of human movements with high resolution, we hypothesized that robotic measures collected longitudinally in patients after stroke would bear a significant relationship to standard clinical outcome measures and, therefore, might provide superior biomarkers.

METHODS

In patients with moderate-to-severe acute ischemic stroke, we used clinical scales and robotic devices to measure arm movement 7, 14, 21, 30, and 90 days after the event at 2 clinical sites. The robots are interactive devices that measure speed, position, and force so that calculated kinematic and kinetic parameters could be compared with clinical assessments.

RESULTS

Among 208 patients, robotic measures predicted well the clinical measures (cross-validated R(2) of modified Rankin scale=0.60; National Institutes of Health Stroke Scale=0.63; Fugl-Meyer=0.73; Motor Power=0.75). When suitably scaled and combined by an artificial neural network, the robotic measures demonstrated greater sensitivity in measuring the recovery of patients from day 7 to day 90 (increased standardized effect=1.47).

CONCLUSIONS

These results demonstrate that robotic measures of motor performance will more than adequately capture outcome, and the altered effect size will reduce the required sample size. Reducing sample size will likely improve study efficiency.

Translation inhibitors induce cell death by multiple mechanisms and Mcl-1 reduction is only a minor contributor

There is significant interest in treating cancers by blocking protein synthesis, to which hematological malignancies seem particularly sensitive. The translation elongation inhibitor homoharringtonine (Omacetaxine mepesuccinate) is undergoing clinical trials for chronic myeloid leukemia, whereas the translation initiation inhibitor silvestrol has shown promise in mouse models of cancer. Precisely how these compounds induce cell death is unclear, but reduction in Mcl-1, a labile pro-survival Bcl-2 family member, has been proposed to constitute the critical event. Moreover, the contribution of translation inhibitors to neutropenia and lymphopenia has not been precisely defined. Herein, we demonstrate that primary B cells and neutrophils are highly sensitive to translation inhibitors, which trigger the Bax/Bak-mediated apoptotic pathway. However, contrary to expectations, reduction of Mcl-1 did not significantly enhance cytotoxicity of these compounds, suggesting that it does not have a principal role and cautions that strong correlations do not always signify causality. On the other hand, the killing of T lymphocytes was less dependent on Bax and Bak, indicating that translation inhibitors can also induce cell death via alternative mechanisms. Indeed, loss of clonogenic survival proved to be independent of the Bax/Bak-mediated apoptosis altogether. Our findings warn of potential toxicity as these translation inhibitors are cytotoxic to many differentiated non-cycling cells.

Properties of proxy-derived modified Rankin Scale assessment

BACKGROUND

Cognitive or communication issues may preclude direct modified Rankin Scale interview, necessitating interview with a suitable surrogate. The clinimetric properties of this proxy modified Rankin Scale assessment have not been described.

AIMS

To describe reliability of proxy-derived modified Rankin Scale and compare with traditional direct patient interview.

METHODS

Researchers assessed consenting stroke inpatients and their proxies using a nonstructured modified Rankin Scale approach. Paired interviewers (trained in modified Rankin Scale) performed independent and blinded modified Rankin Scale assessment of patients and appropriate proxies. Interobserver variability and agreement between patient and proxy modified Rankin Scale were described using kappa statistics (k, 95% confidence interval) and percentage agreement.

RESULTS

Ninety-seven stroke survivors were assessed. Proxies were family members (n = 29), nurses (n = 50), or physiotherapists (n = 25). Median modified Rankin Scale from both patient and proxies was 3 [interquartile range (IQR): 2-4]. Reliability for patient modified Rankin Scale interview was weighted kappa = 0·70 (95% confidence interval: 0·30-1·00). Reliability for proxy modified Rankin Scale weighted kappa = 0·62 (95% confidence interval: 0·34-0·90). Subgroup analysis of various proxy information sources were as follows: family weighted kappa = 0·61; nurse weighted kappa = 0·58; therapist weighted kappa = 0·58. There was disagreement between patient-derived modified Rankin Scale and corresponding proxy modified Rankin Scale weighted kappa = 0·64 (95% CI: 0·42-0·86).

CONCLUSIONS

There is potential for substantial interobserver variability in proxy modified Rankin Scale and validity of certain proxy assessments is questionable. Direct modified Rankin Scale interview is preferred.

Abstract 2466: Inter-observer Reliability and Validity of Pre-morbid Modified Rankin Scale

Background and Purpose: The modified Rankin Scale (mRS) is the most prevalent outcome scale in stroke trials. Utility of standard mRS is limited by inter-observer variability. Pre-morbid function, described using mRS, is often used to determine eligibility for clinical trials or interventions. The clinimetric properties of pre-morbid mRS have not been described previously. We assessed the hypothesis that pre-morbid mRS would have acceptable reliability and validity for clinical use.

Methods: Over a four week period (June 2011), four researchers assessed consenting, sequential stroke unit admissions across two University Hospitals. Paired interviewers (trained in mRS) were randomised to perform independent and blinded mRS assessment of patients. Clinical and demographic details were collated independent of interview. Inter-observer variability was calculated for pre-morbid and standard mRS using kappa ( k ) and weighted kappa ( kw ) with 95% confidence interval (95%CI) and percentage agreement. Validity was assessed by comparing pre-morbid mRS with other markers of function. Number of medications and comorbidity index were compared to pre-morbid mRS (average of paired scores) using rank correlation; proportions living alone with no external care were compared for those with pre-morbid mRS≤1 versus pre-morbid mRS>1 (chi-square test).

Results: Seventy-four stroke survivors were assessed (four proxy assessments); including a variety of stroke types (TACS:13; PACS:27; POCS:9; LACS:15). Median age 72 years (IQR:62-79); median time since event 5 days (IQR:3-9). Median standard mRS was 4 (IQR:2-4). Median pre-morbid mRS was 1 (IQR:0-3; range:0-4); 27 (38%) patients had premorbid disability (mRS>1). Reliability for standard mRS interview was: 56% agreement; k =0.40 (95%CI:0.27-0.52); kw =0.55 (95%CI:0.39-0.71). Reliability of pre-morbid mRS was: 70% agreement; k =0.58 (95%CI:0.46-0.70); kw =0.70.(95%CI:0.53-0.87) Spearman’s Rho for pre-morbid mRS and comorbidity was 0.31 (95%CI:0.08-0.50); for pre-morbid mRS and number of medications was 0.33 (95%CI:0.11-0.52). There was no association between need for carers and pre-morbid mRS (p=0.10).

Conclusions: Inter-observer reliability of pre-morbid mRS is limited but comparable to standard mRS. Poor correlation between markers of previous function and pre-morbid mRS suggest suboptimal validity. Based on these data premorbid mRS may not be a suitable trial entry criterion. There is scope for improvement, improved training and guidance specific to premorbid mRS is a potential solution.

IL-6 promotes acute and chronic inflammatory disease in the absence of SOCS3

The lack of expression of the Suppressor of Cytokine Signalling-3 (SOCS3) or inactivation of the negative regulatory capacity of SOCS3 has been well documented in rheumatoid arthritis, viral hepatitis and cancer. The specific qualitative and quantitative consequences of SOCS3-deficiency on IL-6-mediated pro- and anti-inflammatory responses remain controversial in vitro and unknown in vivo. Mice with a conditional deletion of SOCS3 in hematopoietic cells develop lethal inflammatory disease during adult life and develop gross histopathological changes during experimental arthritis, typified by elevated IL-6 levels. To clarify the nature of the IL-6 responses in vivo, we generated mice deficient in SOCS3 (SOCS3^−/Δvav) or both SOCS3 and IL-6 (IL-6^−/−/SOCS3^−/Δvav) and examined responses in models of acute and chronic inflammation. Acute responses to IL-1β were lethal to SOCS3^−/Δvav mice but not IL-6^−/−/SOCS3^−/Δvav mice, indicating that IL-6 was required for the lethal inflammation induced by IL-1β. Administration of IL-1β to SOCS3^−/Δvav mice induced systemic apoptosis of lymphocytes in the thymus, spleen and lymph nodes that was dependent on the presence of IL-6. IL-6-deficiency prolonged survival of SOCS3^−/Δvav mice and ameliorated spontaneous inflammatory disease developing during adult life. Infection of SOCS3^−/Δvav mice with LCMV induced a lethal inflammatory response that was dependent on IL-6, despite SOCS3^−/Δvav mice controlling viral replication. We conclude that SOCS3 is required for survival during inflammatory responses and is a critical regulator of IL-6 in vivo.

Radial artery hypertrophy occurs in coronary atherosclerosis and is independent of blood pressure

Endothelial dysfunction, believed to underlie the structural changes of atherosclerosis, is a systemic phenomenon. Despite this, the radial artery has been considered as devoid of atherosclerosis and is commonly used as a conduit in coronary artery bypass grafting (CABG). Recently, histological study has shown intimal hyperplasia and other structural changes consistent with early atherosclerosis in the radial artery. The objective of the present study was to determine if structural changes in the radial artery could be detected in vivo in patients with coronary atherosclerosis. Using high resolution echo-tracking, measurements of radial artery internal diameter, wall thickness and wall cross-sectional area were made in 25 patients awaiting CABG and in 20 controls. Digital and brachial blood pressures were also recorded. Mean arterial pressures did not differ between the patient and control groups. All measures of wall thickness were greater in the patient than the control group. Neither current arterial pressures nor past history of hypertension correlated with wall thickness. Using a model of analysis of covariance, coronary artery disease was the best single predictor of intima-media thickness, R(2)=48%, n=44, P<0.0005. We concluded that increased radial artery wall thickness can be demonstrated in vivo in patients with coronary atherosclerosis. This is a novel observation which seems to be independent of blood pressure, and is consistent both with the hypothesis of systemic endothelial dysfunction leading to systemic structural changes and also to the recent histological evidence for atherosclerotic changes in this vessel.

Does potassium channel opening contribute to endothelium-dependent relaxation in human internal thoracic artery?

Opening of potassium channels can cause hyperpolarization and relaxation of vascular smooth muscle cells. The aim of this work was to investigate the contribution of potassium channel activation to vasorelaxation in internal thoracic artery taken from patients undergoing coronary artery bypass graft surgery. Relaxations to carbachol and sodium nitroprusside were studied in isolated rings of internal thoracic artery in the absence and presence of nitric oxide synthase inhibitors and potassium channel blockers. The nitric oxide synthase inhibitors Nomega-nitro-L-arginine methyl ester and NG-monomethyl-L-arginine abolished relaxations to carbachol. Relaxations to both carbachol and sodium nitroprusside were attenuated in the presence of raised extracellular potassium and the potassium channel blockers charybdotoxin, iberiotoxin and tetraethylammonium. Neither apamin nor glibenclamide modified relaxation. ODQ (1H-[1,2,4]oxadiazolol-[4,3a] quinoxalin-1-one), an inhibitor of soluble guanylate cyclase, abolished relaxation to carbachol in rings from some but not all subjects. These results suggest that potassium channel opening may make a small contribution to endothelium-dependent vasorelaxation in internal thoracic artery. The potassium channels had characteristics consistent with those of large-conductance calcium-dependent potassium channels.

Pharmacological characterisation of endothelium-dependent relaxation in human radial artery: comparison with internal thoracic artery

OBJECTIVE

The aim of this study was to investigate the contribution of nitric oxide/prostanoid-independent pathways to endothelium-dependent vasorelaxation in human conduit arteries.

METHODS

Rings of internal thoracic artery (ITA) and radial artery (RA) taken from patients undergoing coronary artery bypass graft surgery were suspended in 10-ml organ baths and relaxation to carbachol and bradykinin studied in the presence and absence of nitric oxide synthase (NOS) inhibitors and potassium channel blockers.

RESULTS

No significant relaxation to carbachol or bradykinin was observed in ITA after NOS inhibition. In contrast, in RA less than 40% attenuation of relaxation to carbachol or bradykinin was achieved with any of the NOS inhibitors. In the presence of 20 mM K+ relaxation to carbachol and bradykinin was inhibited by 28 +/- 9% and 42 +/- 9% while in the presence of L-NAME 200 microM + 20 mM K+ relaxation was inhibited by 66 +/- 6% and 70 +/- 4% respectively in this artery. Tetraethylammonium, glibenclamide, apamin and iberiotoxin had little effect on relaxation to carbachol but charybdotoxin alone and charybdotoxin plus apamin attenuated relaxation to carbachol by 23 +/- 4% and 49 +/- 9% in RA. In the presence of L-NAME 200 microM attenuation of these relaxations were increased to 60 +/- 4% and 78 +/- 4%.

CONCLUSION

In ITA relaxations to carbachol and bradykinin were mediated via nitric oxide. In contrast in RA, a conduit vessel of similar diameter, both nitric oxide-dependent and independent pathways appeared to contribute to vascular relaxation. This nitric oxide-independent relaxation involved opening of Ca2+ activated potassium channel(s). The existence of alternative pathways mediating endothelium-independent relaxation could be important under pathological conditions and may contribute to the long term survival of radial artery grafts.

The Toronto Tri-Hospital Gestational Diabetes Project. A preliminary review

In this study, we assessed maternal-fetal outcomes in untreated patients with increasing carbohydrate intolerance not meeting the current criteria for the diagnosis of gestational diabetes mellitus (GDM), examined the relationship between birth weight and mode of delivery among women with untreated borderline GDM, treated overt GDM, and normoglycemia, and established more efficient screening strategies for detection of GDM. This was a prospective analytic cohort study in which nondiabetic women aged > or = 24 years were eligible for enrollment. A 50-g glucose challenge test (GCT) and a 100-g oral glucose tolerance test (OGTT) were administered at 26 and 28 weeks gestational age, respectively. Risk factors for unfavorable maternal-fetal outcomes were recorded. Time since the last meal prior to the screening test was recorded, as well. Caregivers and patients were blinded to glucose values except when test results met the National Diabetes Data Group criteria for GDM. Maternal and fetal outcomes, including the mode of the delivery, were recorded in the postpartum period. Of 4,274 patients screened, 3,836 (90%) continued to the diagnostic oral glucose tolerance test. GDM was seen in 145 women. Increasing carbohydrate intolerance in women without overt gestational diabetes was associated with a significantly increased incidence of cesarean section, preeclampsia, macrosomia, and need for phototherapy, as well as an increased length of maternal and neonatal hospital stay. Multivariate analysis showed that increasing carbohydrate intolerance remained an independent predictor for various unfavorable outcomes, but the strength of the associations was diminished. Compared with normoglycemic control subjects, the untreated borderline GDM group had increased rates of macrosomia (28.7 vs. 13.7%, P < 0.001) and cesarean delivery (29.6 vs. 20.2%, P = 0.03). Usual care of known GDM patients normalized birth weights, but the cesarean delivery rate was about 33%, whether macrosomia was present or absent. An increased risk of cesarean delivery among treated patients compared with normoglycemic control subjects persisted after adjustment for multiple maternal risk factors. As for the screening tests, time since the last meal had a marked effect on mean plasma glucose. Receiver operating characteristic curve analysis allowed the selection of the most efficient cut points for the GCT based on the time since the last meal. These cut points were 8.2, 7.9, and 8.3 mmol/l (1 mmol/l = 18.015 mg/dl) for elapsed postprandial time of < 2, 2-3, and > 3 h, respectively. With this change from the current threshold of 7.8 mmol/l, the number of patients with a positive screening test dropped from 18.5 to 13.7%. There was an increase in positive predictive value from 14.4 to 18.7%. The overall rate of patient misclassification fell from 18.0 to 13.1%. In conclusion, increasing maternal carbohydrate intolerance in pregnant women without GDM is associated with a graded increase in adverse maternal and fetal outcomes. Infant macrosomia is an important factor in high cesarean delivery rates for women with untreated borderline GDM. Although detection and treatment of GDM normalizes birth weights, rates of cesarean delivery remain inexplicably high. Recognition of GDM may lead to a lower threshold for surgical delivery. The efficiency of screening for GDM can be enhanced by adjusting the current GCT threshold of 7.8 mmol/l to new values related to time since the last meal before screening. Further analyses are underway to elucidate whether maternal risk factors can be used to achieve additional efficiency gains in screening.

Impact of increasing carbohydrate intolerance on maternal-fetal outcomes in 3637 women without gestational diabetes. The Toronto Tri-Hospital Gestational Diabetes Project

OBJECTIVE

Our purpose was to assess maternal-fetal outcomes in patients with increasing carbohydrate intolerance not meeting the current criteria for the diagnosis of gestational diabetes.

STUDY DESIGN

We conducted a prospective analytic cohort study in which nondiabetic women aged > or = 24 years, receiving prenatal care in three Toronto teaching hospitals, were eligible for enrollment. A glucose challenge test and an oral glucose tolerance test were administered at 26 and 28 weeks' gestation, respectively; risk factors for unfavorable maternal-fetal outcomes were recorded. Caregivers and patients were blinded to glucose values except when test results met the current criteria for gestational diabetes.

RESULTS

Of 4274 patients screened, 3836 (90%) continued to the diagnostic oral glucose tolerance test. The study cohort was formed by the 3637 (95%) patients without gestational diabetes, carrying singleton fetuses. Increasing carbohydrate intolerance in women without overt gestational diabetes was associated with a significantly increased incidence of cesarean sections, preeclampsia, macrosomia, and need for phototherapy, as well as an increased length of maternal and neonatal hospital stay. Multivariate analysis showed that increasing carbohydrate intolerance is an independent predictor for various unfavorable outcomes.

CONCLUSION

Increasing maternal carbohydrate intolerance in pregnant women without gestational diabetes is associated with a graded increase in adverse maternal-fetal outcomes.

Impact of time since last meal on the gestational glucose challenge test. The Toronto Tri-Hospital Gestational Diabetes Project

OBJECTIVE

The purpose of the study was to evaluate the impact of time since the last meal on the glucose challenge test and to find cut points that are most likely to predict the outcome of the oral glucose tolerance test in patients screened for gestational diabetes.

STUDY DESIGN

This prospective analytic cohort study was carried out at the University of Toronto Perinatal Complex. A 50 gm glucose load was given at 26 weeks' gestation and the time since previous meal ingestion was recorded. At 28 weeks' gestation a 100 gm oral glucose tolerance test was administered. A total of 4274 eligible patients were screened.

RESULTS

Time since the last meal had a marked effect on mean plasma glucose. Receiver-operator characteristic curve analysis with National Diabetes Data Group criteria to interpret the oral glucose tolerance allowed the selection of the most efficient cut points for the glucose challenge test on the basis of time since the last meal. These cut points were 8.2, 7.9, and 8.3 mmol/L for elapsed postprandial times of < 2, 2 to 3, and > 3 hours, respectively. With this change from the current threshold of 7.8 mmol/L the number of patients with a positive screening test dropped from 18.5% to 13.7%. There was an increase in positive predictive value from 14.4% to 18.7%. The rate of patient misclassification fell from 18.0% to 13.1%.

CONCLUSION

We suggest that screening strategies for detection of gestational diabetes be reconsidered, to account for the impact of variable postprandial status on the test results.

Localization of islet cell tumors by dynamic CT: comparison with plain CT, arteriography, sonography, and venous sampling

Ten patients with suspected islet cell tumors (seven with possible gastrinomas, three with insulinomas) underwent diagnostic evaluation with dynamic CT scanning, routine CT scanning, angiography, and sonography. Venous sampling was also performed in selected instances. Nine sites of gastrinoma and three insulinomas were confirmed surgically in eight patients. Two patients had negative surgical explorations. Routine CT demonstrated five of the nine gastrinomas and one of two insulinomas. Angiography was positive in six of nine gastrinomas and all three insulinomas. Sonography showed only two of the nine gastrinomas and two of the three insulinomas. Dynamic CT scanning demonstrated three additional lesions (two gastrinomas, one insulinoma) not visible on routine CT scanning. Although most of these lesions were visible arteriographically, dynamic CT scans at the appropriate level localized the pathology in the transverse plane and greatly aided in surgical resection of these lesions. Dynamic CT scanning is a useful adjunct to routine angiographic and CT workup of patients with islet cell tumors.

The pre-operative electrocardiogram: an assessment

Electrocardiography is of limited value in pre-operative screening for cardiac disease. A short questionnaire has been shown to be helpful in assessing cardiac status and could permit a 30% reduction in the number of pre-operative ECGs performed.