Prediction of Bleeding in Pediatric Cardiac Surgery Using Clinical Characteristics and Prospective Coagulation Test Results.

Bleeding caused by coagulopathy is common in children undergoing cardiac surgery and causes adverse outcomes. Coagulation testing assists selection of treatments to stop bleeding but has an uncertain role for predicting bleeding. We aimed to evaluate how well prospective coagulation testing predicted excessive bleeding during and after cardiac surgery compared to prediction using clinical characteristics alone. The study was a single-center, prospective cohort study in children having a range of cardiac surgery procedures with coagulation testing at anesthetic induction and immediately after cardiopulmonary bypass. The primary outcome was clinical concern about bleeding (CCB), a composite of either administration of prohemostatic treatments in response to bleeding or a high chest drain volume after surgery. In 225 children, CCB occurred in 26 (12%) during surgery and in 68 (30%) after surgery. Multivariable fractional polynomial models using the clinical characteristics of the children alone predicted CCB during surgery (c-statistic 0.64; 95% confidence interval 0.53, 0.76) and after surgery (0.74; 0.67, 0.82). Incorporating coagulation test results into these models improved prediction (c-statistics 0.79; 0.70, 0.87, and 0.80; 0.74, 0.87, respectively). However, this increased the overall proportion of children classified correctly as CCB or not CCB during surgery by only 0.9% and after surgery by only 0.4%. Incorporating coagulation test results into predictive models had no effect on prediction of blood transfusion or postoperative complications. Prospective coagulation testing marginally improves prediction of CCB during and after cardiac surgery but the clinical impact of this is small when compared to prediction using clinical characteristics.

Health-related quality of life impact of minor and major bleeding events during dual antiplatelet therapy: a systematic literature review and patient preference elicitation study.

BACKGROUND: Dual antiplatelet therapy (DAPT) is the recommended preventative treatment for secondary ischaemic events, but increases the risk of bleeding, potentially affecting patients' health-related quality-of-life (HRQoL). Varied utility decrements have been used in cost-effectiveness models assessing alternative DAPT regimens, but it is unclear which of these decrements are most appropriate. Therefore, we reviewed existing sources of utility decrements for bleeds in patients receiving DAPT and undertook primary research to estimate utility decrements through a patient elicitation exercise using vignettes and the EuroQol EQ-5D. METHODS: MEDLINE, PubMed and references of included studies were searched. Primary research and decision analytic modelling studies reporting utility decrements for bleeds related to DAPT were considered. For the primary research study, 21 participants completed an elicitation exercise involving vignettes describing minor and major bleeds and the EQ-5D-3 L and EQ-5D-5 L. Utility decrements were derived using linear regression and compared to existing estimates. RESULTS: Four hundred forty-two citations were screened, of which 12 studies were included for review. Reported utility decrements ranged from - 0.002 to - 0.03 for minor bleeds and - 0.007 to - 0.05 for major bleeds. Data sources used to estimate the decrements, however, lacked relevance to our population group and few studies adequately reported details of their measurement and valuation approaches. No study completely adhered to reimbursement agency requirements in the UK according to the National Institute for Health and Care Excellence reference case. Our primary research elicited utility decrements overlapped existing estimates, ranging from - 0.000848 to - 0.00828 for minor bleeds and - 0.0187 to - 0.0621 for major bleeds. However, the magnitude of difference depended on the instrument, estimation method and valuation approach applied. CONCLUSIONS: Several sources of utility decrements for bleeds are available for use in cost-effectiveness analyses, but are of limited quality and relevance. Our elicitation exercise has derived utility decrements from a relevant patient population, based on standardised definitions of minor and major bleeding events, using a validated HRQoL instrument and have been valued using general population tariffs. We suggest that our utility decrements be used in future cost-effectiveness analyses of DAPT.

Measurement of myocardium at risk with cardiovascular MR: comparison of techniques for edema imaging.

PURPOSE: To determine variability and agreement for detecting myocardial edema with T2-weighted short-tau inversion recovery (STIR), acquisition for cardiac unified T2 edema (ACUT2E), T2 mapping, and early gadolinium enhancement (EGE) after successfully reperfused ST-segment-elevation myocardial infarction (STEMI) and diagnostic accuracy of each sequence to predict infarct-related artery (IRA). MATERIALS AND METHODS: Local ethics committee approved the study, with patient informed written consent. On day 2 after successful primary angioplasty for STEMI, 53 patients were prospectively enrolled; 40 patients (mean age, 60 years) completed study. Two sets of cardiac magnetic resonance (MR) images were obtained on same day 6 hours apart. Basal, midcavity, and apical sections were obtained with each sequence. Interobserver, intraobserver, and interimage variability (1 minus intraclass correlation coefficient) and agreement (Bland-Altman method) were assessed. RESULTS: Size of myocardial edema significantly differed. Mean size of myocardium at risk was similar between T2-weighted STIR (18.2 g) and T2 mapping (17.3 g) (P = .54). Mean size differed between T2-weighted STIR (18.2 g) and ACUT2E (14.0 g) (P = .01) and between T2-weighted STIR (18.2 g) and EGE (14.2 g) (P = .003). T2 mapping and EGE had best agreement (interobserver bias: T2-weighted STIR, -0.9 [mean difference] ± 9.6 [standard deviation]; ACUT2E, -2.5 ± 6.9; T2 mapping, -3.8 ± 4.7; EGE, -5.3 ± 5.9; interimage bias: T2-weighted STIR, 1.5 ± 5.8; ACUT2E, -0.8 ± 4.9; T2 mapping, 3.1 ± 4.0; EGE, 1.1 ± 4.9; intraobserver bias: T2-weighted STIR, 1.4 ± 5.8; ACUT2E, 0.6 ± 4.7; T2 mapping, 2.2 ± 3.1; EGE, 1.7 ± 2.9). Variability was lowest for T2 mapping (intraobserver, 0.05; interobserver, 0.09; interimage, 0.1) followed by EGE (intraobserver, 0.03; interobserver, 0.14; interimage, 0.14), with improved detection of territory of IRA versus ACUT2E (intraobserver, 0.11; interobserver, 0.22; interimage, 0.12) and T2-weighted STIR (intraobserver, 0.1; interobserver, 0.32; interimage, 0.1). CONCLUSION: Cardiac MR methods to detect and quantify infarct myocardial edema are not interchangeable; T2 mapping is the most reproducible method, followed by EGE, ACUT2E, and T2-weighted STIR. Clinical trial registration no. NCT01468662

Validity and reliability of nerve and muscle ultrasound.

INTRODUCTION: Nerve and muscle ultrasound has been studied in several conditions, but validity and reliability have not been assessed systematically. METHODS: Nerve cross-sectional area and muscle thickness were measured ultrasonographically at several sites in 4 cadavers, which were then dissected, and actual measurements were obtained. To assess intrarater and interrater reliability, between 3 and 5 ultrasonographers, with varying experience levels, made repeated measurements on healthy volunteers. RESULTS: Correlation coefficients for nerve and muscle validity were >0.968 (P < 0.001), and for intrarater reliability were >0.901 (P < 0.001) for still and real-time images. Correlation coefficients for interrater reliability were more varied, but for still images they were all significant at the P < 0.001 (0.542-0.998) level, and for real-time images they were significant at the P < 0.05 level for half the sites (0.243-0.981). CONCLUSION: Overall, nerve and muscle ultrasound is a valid and reliable diagnostic imaging technique.

Quantitative neuromuscular ultrasound in the intensive care unit.

INTRODUCTION: Intensive care unit acquired weakness (ICU-AW) results from a complex mixture of nerve and muscle pathology, and early identification is challenging. This pilot study was designed to examine the ultrasonographic changes that occur in muscles during ICU hospitalization. METHODS: Patients admitted to the ICU for acute respiratory failure were enrolled prospectively and underwent serial muscle ultrasound for thickness and gray-scale assessment of the tibialis anterior, rectus femoris, abductor digiti minimi, biceps, and diaphragm muscles over 14 days. RESULTS: Sixteen participants were enrolled. The tibialis anterior (P = 0.001) and rectus femoris (P = 0.041) had significant decreases in gray-scale standard deviation when analyzed over 14 days. No muscles showed significant changes in thickness. CONCLUSIONS: Ultrasound is an informative technique for assessing muscles of patients in the ICU, and lower extremity muscles demonstrated increased homogeneity during ICU stays. This technique should be examined further for diagnosing and tracking those with ICU-AW.

Epidemiological measures of childhood asthma: cross-sectional and longitudinal consistency.

BACKGROUND: Defining childhood asthma varies considerably, and the extent of agreement between various measures is not clearly understood in the absence of a recognized 'gold standard'. We compared different definitions of childhood asthma, identified characteristics that might have influenced their accuracy and an acquisition of an 'asthma' label in wheezy and treated children. METHODS: Using a prospective, population-based birth cohort of 623 children followed up to the age of 14 years the concordance between parental opinion, doctor's diagnosis reported by the parent and asthma's diagnosis in general practice (GP) was analysed using latent class analysis (LCA). RESULTS: At the age of eight, 'ever asthma' prevalences ranged from 15.5% (parental opinion) to 21.5% (GP record). 35% of children by the age of eight years had at least one reported label of asthma, reflecting both cross sectional and longitudinal inconsistencies. By the age of 14 years, 16% of children were inconsistently defined as 'ever asthmatic' by their parents. The prevalence of 'ever asthma' estimated by LCA was 19.3%, indicating a parental report of a doctor's diagnosis to be the most sensitive and specific definition. The likelihood of being labelled with asthma was higher in those with a parental or sibling history of asthma, but not determined by socio-demographic characteristics. CONCLUSIONS: Although the estimates of prevalence were similar for parental reports and GP records, agreement between the three sources was less than expected. Parental report of a doctor's diagnosis of asthma is sensitive, specific, longitudinally consistent and not subject to large socio-economic bias.

Recorded infections and antibiotics in early life: associations with allergy in UK children and their parents.

BACKGROUND: It is suggested that the inverse relationship between allergic disease and family size reflects reduced exposure to early life infections, and that antibiotic treatment in childhood diminishes any protective effect of such infection. METHODS: A birth cohort study was undertaken in 642 children recruited before birth and seen annually until the age of 8 years. Reported infections and prescribed antibiotics by the age of 5 years were counted from GP records and comparisons were made with a previous study of their parents. RESULTS: At the age of 8 years, 104 children (19%) were atopic, 79 (13%) were currently wheezy and 124 (21%) had seasonal rhinitis. 577 children (97%) had at least three infections recorded by age 5, a figure much higher than that of their parents (69%). By the age of 5 only 11 children (2%) had never received a prescription for antibiotics; the corresponding figure for the parents was 24%. Higher numbers of infections were recorded for firstborn children. After adjusting for parental atopy and birth order, there was no association between infection counts and atopy (OR 1.01 (95% CI 0.99 to 1.03) per infection). Significant positive associations were found for wheeze and seasonal rhinitis. An increased risk of current wheeze was found for each antibiotic prescription (adjusted OR 1.07 (95% CI 1.03 to 1.10)) but not for atopy. This was primarily explained by prescriptions for respiratory infections. Similar patterns were observed for seasonal rhinitis. CONCLUSIONS: Despite very high rates of recorded early life infections and antibiotic prescriptions, no plausibly causative relationships were found with subsequent respiratory allergies.