A Review of Implementation Concepts and Strategies Surrounding Traumatic Brain Injury Clinical Care Guidelines

Despite considerable efforts to advance the science surrounding traumatic brain injury (TBI), formal efforts supporting the current and future implementation of scientific findings within clinical practice and healthcare policy are limited. While many and varied guidelines inform the clinical management of TBI across the spectrum, clinicians and healthcare systems are not broadly adopting, implementing, and/or adhering to them. As part of the Brain Trauma Blueprint TBI State of the Science, an expert workgroup was assembled to guide this review article, which describes: (1) possible etiologies of inadequate adoption and implementation; (2) enablers to successful implementation strategies; and (3) strategies to mitigate the barriers to adoption and implementation of future research.

Epidemiology of Chronic Effects of Traumatic Brain Injury

Although many patients diagnosed with traumatic brain injury (TBI), particularly mild TBI, recover from their symptoms within a few weeks, a small but meaningful subset experience symptoms that persist for months or years after injury and significantly impact quality of life for the person and their family. Factors associated with an increased likelihood of negative TBI outcomes include not only characteristics of the injury and injury mechanism, but also the person’s age, pre-injury status, comorbid conditions, environment, and propensity for resilience. In this article, as part of the Brain Trauma Blueprint: TBI State of the Science framework, we examine the epidemiology of long-term outcomes of TBI, including incidence, prevalence, and risk factors. We identify the need for increased longitudinal, global, standardized, and validated assessments on incidence, recovery, and treatments, as well as standardized assessments of the influence of genetics, race, ethnicity, sex, and environment on TBI outcomes. By identifying how epidemiological factors contribute to TBI outcomes in different groups of persons and potentially impact differential disease progression, we can guide investigators and clinicians toward more-precise patient diagnosis, along with tailored management, and improve clinical trial designs, data evaluation, and patient selection criteria.

Sediment Characterization at the Equatorial Mid-Atlantic Ridge From P-to-S Teleseismic Phase Conversions Recorded on the PI-LAB Experiment

Accurate marine sediment characteristics, for example, thickness and seismic velocity, are important for constraining sedimentation rates with implications for climate variations and for seismic imaging of deeper structures using ocean bottom seismic deployments. We analyze P-to-S seismic phase conversions from the sediment-crust boundary recorded by the Passive Imaging of the Lithosphere-Asthenosphere Boundary (PI-LAB) experiment to infer the sediment thickness across the Mid-Atlantic Ridge covering 0- to 80-Myr-old seafloor. We find P d s-P delay times of 0.04-0.37 s, or 5- to 82-m thickness. Sediment thickness increases with age. Thickness agrees with global estimates for young (<15-20 Myr) seafloor but is thinner on older lithosphere. Our result may represent a lower limit on sediment thickness, given that several of our stations are on topographic highs. The sedimentation rate decrease observed from 5 to 1.2 mm/kyr at ∼10 Myr suggests a recent increase in productivity related to climate change, eolian dust fluxes, and/or biogenic marine activity.

Pediatric bacteremia caused by Chromobacterium haemolyticum/Chromobacterium aquaticum

We present a case of pediatric bacteremia caused by Chromobacterium haemolyticum, a β-hemolytic, non-pigmented, Gram-negative bacilli recovered from a blood culture and initially identified as Chromobacterium violaceum using phenotypic and proteomic methods. 16S rRNA sequencing of the patient isolated demonstrated a high degree of sequence homology with the type strain of C. haemolyticum. The patient recovered following treatment with meropenem, gentamicin, and trimethoprim/sulfamethoxazole. This case highlights the potential misidentification of C. haemolyticum as non-pigmented C. violaceum due to limitations of the currently available identification methodologies.

A new direct test of bladder permeability

PURPOSE

A proposed cause of interstitial cystitis is increased bladder permeability but to our knowledge this theory has not been proved by direct testing. We developed a safe, relatively painless, direct test of bladder permeability.

MATERIALS AND METHODS

The original permeability test involved placing 4% lactulose and 1% rhamnose intravesically, then drawing blood to assay for these sugars. Initial feasibility studies were performed in rabbits with bladder epithelium that was intact or disrupted by a 50% acetone rinse. In humans the initial goal was to distinguish intact bladders from those known to have increased permeability. Since distention is known to increase permeability temporarily, we studied patients with interstitial cystitis immediately after distention.

RESULTS

Neither sugar was absorbed from intact rabbit bladders, while each was absorbed from acetone rinsed bladders at 10, 20 and 30 minutes. We used 100 ml. of solution in the initial 8 humans, including 6 with interstitial cystitis and 2 controls. At 30 minutes each sugar was absorbed from interstitial cystitis bladders but neither was absorbed from intact bladders. The test solution was then changed to 5% rhamnose. Mean rhamnose absorption plus or minus standard deviation was much greater in the 6 patients with interstitial cystitis than in 8 controls (26.3 + or - 26.1 versus 0.78 + or - 0.87 nmol. /ml. serum, p = 0.008). With 1 exception interstitial cystitis serum levels were at least 4-fold higher than the highest control level.

CONCLUSIONS

This new permeability test clearly distinguishes intact versus distended bladders. It may be performed to test whether bladder permeability is increased in interstitial cystitis.

Reliability of potential clinical measures of muscle tone in the elbows of patients after stroke

OBJECTIVES

This study investigated the reliability of joint resting position (EJP), resistance to passive movement (ERM), and the angle of appearance of the resistance (EAR) as measures of muscle hypertonus of elbow flexors in patients after stroke. Previously, similar measures had been found reliable when applied to measuring shoulder and wrist hypertonus in patients after stroke.

METHOD

Forty-five subjects with stroke were randomly selected from occupational therapy admissions at two rehabilitation centers. Tone of elbow flexors was measured twice at the same sitting by two examiners. EJP and EAR were measured with a goniometer, and ERM was measured with a resistance rating scale. Correlations were calculated between first and second measurements by center and by high tone and poor upper extremity function subgroups (with correction for multiple correlations) to determine reliability.

RESULTS

Each of the three measures was highly reliable as demonstrated by a high correlation in at least one of the subgroups (Center 1: EJP, r = .964 for high tone subgroup; ERM, r = .789, EAR, r = .902, both in poor upper extremity function subgroup; and Center 2: EJP, r = .892, ERM, r = .938, both in poor upper extremity function subgroup; EAR, r = .666 for all subjects; all p values < .05). Correlations were especially high when data for subjects with high upper extremity function were eliminated.

CONCLUSION

Reliability of these three methods of measuring upper extremity muscle tone enhances their usefulness as well as therapists' confidence in their judicial application.