A Pediatric Cervical Spine Clearance Guideline Leads to Fewer Unnecessary Computed Tomography Scans and Decreased Radiation Exposure.

OBJECTIVES: Physical examination and computed tomography (CT) are useful to rule out cervical spine injury (CSI). Computed tomography scans increase lifetime cancer risk in children from radiation exposure. Most CSI in children occur between the occiput and C4. We developed a cervical spine (C-spine) clearance guideline to reduce unnecessary CTs and radiation exposure in pediatric trauma patients. METHODS: A pediatric C-spine clearance guideline was implemented in September 2018 at our Level 2 Pediatric Trauma Center. Guidance included CT of C1 to C4 to scan only high-yield regions versus the entire C-spine and decrease radiation dose. A retrospective cohort study was conducted comparing preguideline and postguideline of all pediatric trauma patients younger than 8 years screened for CSI from July 2017 to December 2020. Primary endpoints included the following: number of full C-spine and C1 to C4 CT scans and radiation dose. Secondary endpoints were CSI rate and missed CSI. Results were compared using χ 2 and Wilcoxon rank-sum test with P < 0.05 significant. RESULTS: The review identified 726 patients: 273 preguideline and 453 postguideline. A similar rate of total C-spine CTs were done in both groups (23.1% vs 23.4%, P = 0.92). Full C-spine CTs were more common preguideline (22.7% vs 11.9%, P < 0.001), whereas C1 to C4 CT scans were more common post-guideline (11.5% vs 0.4%, P < 0.001). Magnetic resonance imaging utilization and CSIs identified were similar in both groups. The average radiation dose was lower postguideline (114 vs 265 mGy·cm -1 ; P < 0.001). There were no missed CSI. CONCLUSIONS: A pediatric C-spine clearance guideline led to increasing CT of C1 to C4 over full C-spine imaging, reducing the radiation dose in children. LEVEL OF EVIDENCE: Level IV, therapeutic.

Severe liver dysfunction in a toddler receiving nonprescription phytocannabinoid.

BACKGROUND: Nonprescription cannabis products are becoming widely available and being promoted for various health conditions. Safety profile of these products apart from psychoactive effects has not been studied and published well. Liver dysfunction is well described in literature with high doses of recreational tetrahydrocannabinol and cannabidiol products but not with nonprescription phytocannabinoids products used for various medicinal values. CASE SUMMARY: A 2-year-old unimmunized male with infantile spasms and refractory seizures, managed with clobazam and zonisamide, presented for respiratory illness and incidentally diagnosed with severe liver dysfunction with elevated coagulation markers. He did not manifest any clinical signs of liver failure. On further review, it was found that parents were using nonprescription phytocannabinoids (hemp extract) for his neurological condition. He required supportive care for his liver dysfunction, and liver enzymes down trended gradually after holding his phytocannabinoid products. The World Health Organization-Uppsala Monitoring Centre approach puts the presentation as probable/likely category of adverse reaction for liver dysfunction with phytocannabinoid ingestion. PRACTICAL IMPLICATIONS: The case we present shows the detrimental effects of over-the-counter phytocannabinoid products, which could point toward the role of phytocannabinoids in this pathophysiology. The case highlights the importance of awareness of potential life-threatening consequences of these products and educating the patient and the caregivers of these risks. The case also emphasizes the need for serial liver enzymes monitoring for patients receiving these therapies as well as extensive research focusing on safety profile of these products in terms of different organ system affection other than their psychoactive potential.

A Survey Assessing Pediatric Transport Team Composition and Training.

OBJECTIVE: The aim of this study was to assess national pediatric/neonatal specialty transport teams' composition and training requirements to determine if any current standardization exists. METHODS: This was a survey of the transport teams listed with the American Academy of Pediatrics via SurveyMonkey. RESULTS: While most of the teams maintain internal criteria for team competency and training, there is large variation across team compositions. The vast majority of the teams have a nurse-led team with the addition of another nurse, medic, and/or respiratory therapist regardless of mode of transport. Many of the teams report adjusting team composition based on acuity. Fewer than 15% of teams have a physician as a standard team member. More than 80% required a minimum number of supervised intubations prior to independent practice; however, the number varied largely from as little as 3 to as many as 30. Eighty-eight percent of the teams report using simulation as part of their education program, but again there were marked differences between teams as to how it was used. CONCLUSIONS: There is tremendous variability nationally among pediatric/neonatal transport teams regarding training requirements, certifications, and team composition. The lack of standardization regarding team member qualifications or maintenance of competency among specialized transport teams should be looked at more closely, and evidence-based guidelines may help lead to further improved outcomes in the care of critically ill pediatric patients in the prehospital setting.

VU6005806/AZN-00016130, an advanced M4 positive allosteric modulator (PAM) profiled as a potential preclinical development candidate.

This letter describes progress towards an M4 PAM preclinical candidate that resulted in the discovery of VU6005806/AZN-00016130. While the thieno[2,3-c]pyridazine core has been a consistent feature of key M4 PAMs, no work had previously been reported with respect to alternate functionality at the C3 position of the pyridazine ring. Here, we detail new chemistry and analogs that explored this region, and quickly led to VU6005806/AZN-00016130, which was profiled as a putative candidate. While, the ß-amino carboxamide moiety engendered solubility limited absorption in higher species precluding advancement (or requiring extensive pharmaceutical sciences formulation), VU6005806/AZN-00016130 represents a new, high quality preclinical in vivo probe.

Does Simulation Improve Recognition and Management of Pediatric Septic Shock, and If One Simulation Is Good, Is More Simulation Better?

OBJECTIVES: Determine whether serial simulation training sessions improve resident recognition and initial septic shock management in a critically ill simulated septic shock patient, and to determine whether serial simulations further improve resident task performance when compared with a single simulation session. DESIGN: Prospective observational cohort study with a live expert review of trainee simulation performance. Expert reviewers blinded to prior trainee performance. SETTING: A PICU room in a quaternary-care children's hospital, featuring a hi-fidelity pediatric patient simulator. SUBJECTS: Postgraduate year-2 and postgraduate year-3 pediatric residents who rotate through the PICU. INTERVENTIONS: Postgraduate year-3 residents as the control cohort, completing one simulation near the start of their third residency year. Postgraduate year-2 residents as the intervention cohort, completing two simulations during their second residency year and one near the start of their third residency year. MEASUREMENTS AND MAIN RESULTS: Resident objective performance was measured using a validated 27-item checklist (graded 0/1) related to monitoring, data gathering, and interventions in the diagnosis and management of pediatric septic shock. The intervention cohort had a higher mean performance percentage score during their third simulation than the control cohort completing their single simulation (87% vs 77%; p < 0.001). Septic shock was correctly diagnosed more often in the intervention cohort at the time of their third simulation (100% vs 78%; p < 0.001). Appropriate broad-spectrum antibiotics were administered correctly more often in the intervention cohort (83% vs 50%; p < 0.001). CONCLUSIONS: Simulations significantly improved resident performance scores in the management of septic shock with repetitive simulation showing significant ongoing improvements. Further studies are needed to determine long-term impact on knowledge and skill retention and whether results attained in a simulation environment are translatable into clinical practice in improving bedside care.

Quasi-phase matched second-harmonic generation through thermal poling in femtosecond laser-written glass waveguides.

Quasi-phase matched second-harmonic generation at 532 nm is demonstrated in a channel waveguide that is written in bulk fused silica using a femtosecond laser. The second-order nonlinear grating is fabricated using uniform thermal poling followed by periodic erasure inside an e-beam deposition system caused, by what we believe to be, x-rays. A SHG conversion efficiency of 2 x10(-5) %/W-cm(2) was obtained for a 1 cm long device, corresponding to an effective nonlinear coefficient of 0.0075 pm/V.

Microfluidic sorting system based on optical waveguide integration and diode laser bar trapping.

Effective methods for manipulating, isolating and sorting cells and particles are essential for the development of microfluidic-based life science research and diagnostic platforms. We demonstrate an integrated optical platform for cell and particle sorting in microfluidic structures. Fluorescent-dyed particles are excited using an integrated optical waveguide network within micro-channels. A diode-bar optical trapping scheme guides the particles across the waveguide/micro-channel structures and selectively sorts particles based upon their fluorescent signature. This integrated detection and separation approach streamlines microfluidic cell sorting and minimizes the optical and feedback complexity commonly associated with extant platforms.

Nanoindentation and birefringence measurements on fused silica specimen exposed to low-energy femtosecond pulses.

Femtosecond laser pulses used in a regime below the ablation threshold have two noticeable effects on Fused Silica (a-SiO2): they locally increase the material refractive index and modify its HF etching selectivity. The nature of the structural changes induced by femtosecond laser pulses in fused silica is not fully understood. In this paper, we report on nanoindentation and birefringence measurements on fused silica exposed to low-energy femtosecond laser pulses. Our findings further back the hypothesis of localized densification effect even at low energy regime.

Monolithic optofluidic ring resonator lasers created by femtosecond laser nanofabrication.

We designed, fabricated, and characterized a monolithically integrated optofluidic ring resonator laser that is mechanically, thermally, and chemically robust. The entire device, including the ring resonator channel and sample delivery microfluidics, was created in a block of fused-silica glass using a 3-dimensional femtosecond laser writing process. The gain medium, composed of Rhodamine 6G (R6G) dissolved in quinoline, was flowed through the ring resonator. Lasing was achieved at a pump threshold of approximately 15 µJ mm(-2). Detailed analysis shows that the Q-factor of the optofluidic ring resonator is 3.3 × 10(4), which is limited by both solvent absorption and scattering loss. In particular, a Q-factor resulting from the scattering loss can be as high as 4.2 × 10(4), suggesting the feasibility of using a femtosecond laser to create high quality optical cavities.

Fabrication of high-aspect ratio, micro-fluidic channels and tunnels using femtosecond laser pulses and chemical etching.

We present novel results obtained in the fabrication of high-aspect ratio micro-fluidic microstructures chemically etched from fused silica substrates locally exposed to femtosecond laser radiation. A volume sampling method to generate three-dimensional patterns is proposed and a systematic SEM-based analysis of the microstructure is presented. The results obtained gives new insights toward a better understanding of the femtosecond laser interaction with fused silica glass (a-SiO(2)).

Fabrication and characterization of microstructures with optical quality surfaces in fused silica glass using femtosecond laser pulses and chemical etching.

We present a study of the sidewall surface quality inside microchannels fabricated in fused silica glass by femtosecond laser pulses and chemical etching. Multiple combinations of laser exposure and etching solution parameters were examined. Results of scanning electron microscopy, atomic force microscopy, and optical reflection analyses of the surfaces are presented. The results obtained demonstrate the feasibility of optical quality surface fabrication, which in turn demonstrates the feasibility of fabricating complex integrated devices containing microfluidic channels and optical waveguides in the glass substrates.

Waveguide electro-optic modulator in fused silica fabricated by femtosecond laser direct writing and thermal poling.

An integrated electro-optic waveguide modulator is demonstrated in bulk fused silica. A Mach-Zehnder interferometer waveguide structure is fabricated by direct writing with a femtosecond laser followed by thermal poling. A 20 degrees electro-optic phase shift is achieved at an operating wavelength of 1.55 microm with an applied voltage of 400 V and an interaction length of 25.6 mm, which correspond to an estimated effective electro-optic coefficient of 0.17 pm/V for the TE-polarized mode.