Post-thrombotic syndrome in children: Measurement properties of CAPTSure, a new diagnostic tool.

BACKGROUND: CAPTsure (Clinical Assessment of PTS) is a new tool for diagnosis and severity rating of pediatric postthrombotic syndrome (PTS). Our objective was to test the reliability, measurement error, and minimal detectable change of CAPTSure. METHODS: Children aged newborn to 18 years who sustained upper extremity or lower extremity deep vein thrombosis (DVT) were enrolled ≥ 6 months after DVT diagnosis. Patients were assessed by 2 raters to determine the reliability of the clinician assessment component (CC) of CAPTSure. Patients/proxies completed CAPTSure at baseline and approximately 2 weeks later to assess test-retest reliability of the symptoms component (SC). RESULTS: Of 148 patients enrolled in the study; 30 had sustained either bilateral or both upper and lower extremity DVT. Hence, 178 extremities were assessed for PTS signs (86 upper extremity, 92 lower extremity). Intraclass correlation coefficient (ICC) for the CC was 0.89 (95% confidence interval [CI], 0.84-0.93) for upper extremity and 0.88 (95% CI, 0.83-0.92) for lower extremity. Nonclinicians performed 59% of measurements. Ninety-eight patients completed the SC at baseline and follow-up, for a total of 60 upper extremity and 61 lower extremity assessments. ICC for the SC was 0.89 (95% CI, 0.84-0.93) for upper extremity and 0.92 (0.87-0.95) for lower extremity. ICC for CAPTSure was 0.92 (95% CI, 0.87-0.95) for upper extremity and 0.93 (95% CI, 0.88-0.95) for lower extremity assessment. Measurement error ranged between 1.7 and 4.3 of 100 points. A change of approximately 11 of 100 points in CAPTSure score would be required to be confident that there was a change in PTS severity. CONCLUSION: CAPTSure has excellent reliability and a small measurement error, even when applied by nonhematologists.

Outcomes and risk factors of massive and submassive pulmonary embolism in children: a retrospective cohort study.

BACKGROUND: Little is known about severe pulmonary embolism in children. We aimed to report pulmonary embolism outcomes, identify risk factors for unfavourable outcomes, and evaluate the discriminative ability of two clinical-severity indices in children. METHODS: In this retrospective cohort study, we included consecutive patients aged 18 years or younger with acute pulmonary embolism, objectively diagnosed radiologically or pathologically, between Jan 1, 2000, and Dec 31, 2016, from two Canadian paediatric hospitals (The Hospital for Sick Children, Toronto, ON, and the Children's Hospital of Eastern Ontario, Ottawa, ON). Exclusion criteria were sudden death without radiological or pathological pulmonary embolism confirmation and non-thromboembolic pulmonary embolism. The primary outcome was a composite of unfavourable outcomes of pulmonary embolism-related death and pulmonary embolism recurrence or progression. Potential predictors of the composite unfavourable outcome (ie, age at pulmonary embolism diagnosis, sex, underlying cardiac disease, severity of the pulmonary embolism, presence of a central venous catheter, associated venous thromboembolism, family history of thrombosis, treatment modalities, thrombophilia, obesity, and recent surgery) were explored with logistic regression. We calculated pulmonary embolism severity index (PESI) and simplified PESI (sPESI) using age-adjusted parameters; we estimated the ability of PESI and sPESI to predict mortality using receiver-operating characteristic (ROC) curve analysis. FINDINGS: Of the 170 patients included, 37 (22%) had massive, 12 (7%) submassive, and 121 (71%) non-massive pulmonary embolism. Patients with massive or submassive pulmonary embolism were younger (median age 12·5 years [IQR 0·6-15·1] vs 14·4 years [9·3-16·1], p<0·0001), more likely to have a cardiac condition (16 [33%] vs 17 [14%] patients, p=0·009), and had more central venous catheters (29 [59%] vs 48 [40%] patients, p=0·027) than patients with non-massive pulmonary embolism. Aggressive treatment modalities were more commonly used in massive or submassive pulmonary embolism (22 [45%] vs 7 [6%] patients, p<0·0001). Of the predictors tested, only pulmonary embolism severity was associated with the composite unfavourable outcome in the multivariable analysis (odds ratio 3·53, 95% CI 1·69-7·36; p=0·011). The area under the ROC curve for PESI to predict 30-day mortality was 0·76 (95% CI 0·64-0·87). Sensitivity of sPESI was 100% and specificity was 30%. INTERPRETATION: Massive or submassive pulmonary embolism led to higher rates of unfavourable outcomes than non-massive pulmonary embolism in children. Further adaptations of PESI and sPESI are required to improve their clinical usefulness in paediatric patients. FUNDING: Trainee Start-Up Fund (The Hospital for Sick Children).

Postthrombotic syndrome and other outcomes of lower extremity deep vein thrombosis in children.

Pediatric lower extremity deep vein thrombosis (LE-DVT) can lead to postthrombotic syndrome (PTS) and other adverse events. We investigated the outcomes of LE-DVT in children. Three groups were compared: non-line-related (Non-LR) DVT, LR DVT in neonates (LRneonates), and LR DVT in non-neonates (LRnon-neonates). A total of 339 children were included (Non-LR, n = 56; LRneonates, n = 95; and LRnon-neonates, n = 188). We found a statistically significant difference in the frequency of PTS (P = .04; 62.5%, 40.0%, and 46.3% in Non-LR, LRneonates, and LRnon-neonates, respectively), of recurrent LE-DVT (P = .001; 10.7% and 2.0% in Non-LR and LRnon-neonates, respectively), and pulmonary embolism (PE) (P < .001; 19.6% and 3.2% in Non-LR and LRnon-neonates, respectively) among groups. There was no difference in DVT resolution (P = .41). Multivariable analysis showed that DVT resolution, triggering event, and sex predicted Modified Villalta Scale (MVS; for pediatric PTS) scores >1; there was an interaction between DVT triggering event and sex. The time to reach an MVS >1 was significantly different when comparing groups (log-rank test, P < .001). Moreover, we found a significant difference in baseline MVS scores among groups, but the difference did not appear to change over time. In conclusion, LR LE-DVT had more benign outcomes than Non-LR DVT. Sex, DVT triggering event, and DVT resolution predicted LE-PTS in our cohort.

A critical review of scoring options for clinical measurement tools.

BACKGROUND: The aim of this paper is twofold: (1) to describe the fundamental differences between formative and reflective measurement models, and (2) to review the options proposed in the literature to obtain overall instrument summary scores, with a particular focus on formative models. METHODS: An extensive literature search was conducted using the following databases: MEDLINE, EMBASE, PsycINFO, CINAHL and ABI/INFORM, using "formative" and "reflective" as text words; relevant articles' reference lists were hand searched. RESULTS: Reflective models are most frequently scored by means of simple summation, which is consistent with the theory underlying these models. However, our review suggests that formative models might be better summarized using weighted combinations of indicators, since each indicator captures unique features of the underlying construct. For this purpose, indicator weights have been obtained using choice-based, statistical, researcher-based, and combined approaches. CONCLUSION: Whereas simple summation is a theoretically justified scoring system for reflective measurement models, formative measures likely benefit from the use of weighted scores that preserve the contribution of each of the aspects of the construct.

Normal values for segmental bioimpedance spectroscopy in pediatric patients.

INTRODUCTION: Localized limb edema is a clinically relevant sign in diseases such as post-thrombotic syndrome and lymphedema. Quantitative evaluation of localized edema in children is mainly done by measuring the absolute difference in limb circumference, which includes fat and fat-free mass. Bioimpedance spectroscopy (BIS) provides information on the fluid volume of a body segment. Our objective was to determine normal ranges for segmental (arm and leg) BIS measurements in healthy children. Additionally, we determined the normal ranges for the difference in arm and ankle circumference and explored the influence of handedness and the correlation between techniques. METHODS: Healthy children aged 1-18 years were recruited. The ratio of extracellular fluid content between contralateral limbs (estimated as the inter-arm and inter-leg extracellular impedance ratio), and the ratio of extracellular to intracellular fluid content for each limb (estimated as the intracellular to extracellular impedance ratio) were determined with a bioimpedance spectrometer. Arm and ankle circumference was determined with a Gulick II tape. RESULTS: We recruited 223 healthy children (48 infants, 54 preschoolers, 66 school-aged children, and 55 teenagers). Normal values for arm and leg BIS measurements, and for the difference in arm and ankle circumference were estimated for each age category. No influence of handedness was found. We found a statistically significant correlation between extracellular impedance ratio and circumference difference for arms among teenagers. CONCLUSION: We determined normal BIS ranges for arms and legs and for the difference in circumference between arms and between ankles in children. There was no statistically significant correlation between extracellular impedance ratio and difference in circumference, except in the case of arms in adolescents. This may indicate that limb circumference measures quantities other than fluid, challenging the adequacy of this technique to determine the presence of localized edema in most age groups.