Dynamic vapor microextraction of ignitable liquid from casework containers.

Dynamic vapor microextraction (DVME) is a headspace concentration method that can be used to collect ignitable liquid (IL) from fire debris onto chilled adsorbent capillaries. Unlike passive headspace concentration onto activated carbon strips (ACSs) that must be eluted with a toxic solvent (carbon disulfide), DVME employs a relatively benign solvent (acetone) to recover the adsorbed IL residue, and each headspace collection is monitored for breakthrough. Here, for the first time, we extend DVME to casework containers while exploring a realistic range of oven temperatures and collection volumes. We investigated metal cans sealed with friction lids (container 1), metal cans sealed within polymer bags (container 2), and glass jars sealed with two-piece lids (container 3). Without additional containment, container 1 was found to leak so excessively that flow through the capillary was unreliable. Therefore, for containers 2 and 3 only, we determined the total number of target compounds collected from 50% weathered gasoline for oven temperatures from 54 °C to 96 °C and collection volumes from 47 standard cubic centimeters (scc) to 90 scc. Only high-volatility species with retention times (tR)< n-decane on a non-polar column were recovered from polymer bags, whereas headspace concentration from glass jars led to the recovery of target compounds across the entire volatility range. DVME at 90 °C from 2-mL containers showed that the presence of polymer bag material leads to IL vapor losses, particularly for low-volatility species with tR> n-decane. DVME was strongly influenced by the casework container, whereas oven temperature and collection volume had a minor influence for the IL samples explored here.

Children's Hospital Transfers From Referring Emergency Departments: Which Patients Bypassed the Pediatric Emergency Department?

OBJECTIVES: Children are increasingly transferred from emergency departments (EDs) to children's hospitals for inpatient care. The existing literature on the use of direct admission (DA) specifically among pediatric patients transferred from referring EDs remains sparse.The objective of this study was to identify demographic, clinical, and contextual factors associated with the use of direct-to-inpatient versus ED-to-inpatient admission among patients transferred to children's hospitals from EDs. METHODS: This was a retrospective chart review of nontrauma patients admitted to inpatient services at a single tertiary children's hospital after interfacility transfer from EDs between July 1, 2016, and June 30, 2017. Characteristics of the patient population and referring EDs were described; unadjusted associations between rates of DA and the demographic, clinical, and contextual variables of encounters were performed; and a logistic model quantified the relevant associations as odds ratios (ORs). RESULTS: Of 2939 study encounters, 78% resulted in DA. Among White patients, private insurance was associated with decreased direct admission (OR, 0.5; 95% confidence interval [CI], 0.4-0.8). Younger patients and patients with respiratory diagnoses (OR, 3.9; 95% CI, 2.8-5.3) had increased likelihood of DA. Patients with gastrointestinal diagnoses had decreased likelihood of DA (OR, 0.6; 95% CI, 0.4-0.7). CONCLUSIONS: At a tertiary hospital with a high rate of DA among patients transferred from other EDs, we identified factors that were associated with the use of direct versus ED admission. Our results identify specific populations in which future work could inform admission processes for interfacility transfers.

Interrater Reliability of the Pediatric Neuromuscular Recovery Scale for Spinal Cord Injury.

Background: In synergy with the mounting scientific evidence for the capacity of recovery after spinal cord injury (SCI) and training, new evidence-based therapies advancing neuromuscular recovery are emerging. There is a parallel need for outcome instruments that specifically address recovery. The Pediatric Neuromuscular Recovery Scale (Pediatric NRS) is one example with established content validity to assess neuromuscular capacity within task performance. Objective: The objective of this study was to determine interrater reliability of the Pediatric NRS to classify motor capacity in children after SCI. Methods: Pediatric physicians (3), occupational therapists (5), and physical therapists (6) received standardized training in scoring the scale, then rated video assessments of 32 children post SCI, 2-12 years of age, 78% non-ambulatory. Interrater reliability was analyzed using Kendall coefficient of concordance for individual Pediatric NRS items and overall score. Results: The interrater reliability coefficient was determined to be near 1 for the overall Pediatric NRS score (ICC = 0.966; 95% CI, 0.89-0.98). Twelve of 16 individual items exhibited high concordance coefficients (Kendall's W ≥ 0.8) and four items demonstrated concordance coefficients, < 0.8 and > 0.69. Interrater reliability was equivalent among groups defined by age and neurological level, but lower among non-ambulatory individuals. Conclusion: Strong interrater reliability was demonstrated by pediatric clinicians who scored children with SCI using the Pediatric NRS.

A log rank test for clustered data with informative within-cluster group size.

The log rank test is a popular nonparametric test for comparing survival distributions among groups. When data are organized in clusters of potentially correlated observations, adjustments can be made to account for within-cluster dependencies among observations, eg, tests derived from frailty models. Tests for clustered data can be further biased when the number of observations within each cluster and the distribution of groups within cluster are correlated with survival times, phenomena known as informative cluster size and informative within-cluster group size. In this manuscript, we develop a log rank test for clustered data that adjusts for the potentially biasing effect of informative cluster size and within-cluster group size. We provide the results of a simulation study demonstrating that our proposed test remains unbiased under cluster-based informativeness, while other candidate tests not accounting for the clustering structure do not properly maintain size. Furthermore, our test exhibits power advantages under scenarios in which traditional tests are appropriate. We demonstrate an application of our test by comparing time to functional progression between groups defined initial functional status in a spinal cord injury data set.