A protocol-driven approach to reduce lengths of stay for pediatric blunt liver and spleen injury patients.

BACKGROUND: Our institution updated blunt liver and spleen injury (BLSI) protocols in 2019 in adherence to updated American Pediatric Surgery Association recommendations. This retrospective study compares resource utilization for pediatric BLSI patients treated under old and updated guidelines. METHODS: Blunt liver and spleen injury patients without severe non-abdomen injuries younger than 18 years treated with prior (April 2015 to June 2019) and updated (June 2019 to December 2022) guidelines were retrospectively reviewed and compared. Each patient received an adjusted Injury Severity Score (ISS) to control for non-BLSI injuries. Multivariate analysis examined protocol group differences while controlling for adjusted ISS and BLSI grades. Primary outcomes were intensive care unit (ICU) length of stay (LOS), hospital LOS (analyzed using Cox regression), and patient costs (linear regression). Secondary outcomes include readmission in 2 weeks and death rates (logistic regression). RESULTS: A total of 176 and 170 BLSI patients were treated with old and updated protocols, respectively. Patient demographics, average BLSI grade, and adjusted ISS were similar in both groups. Patients treated with old protocols indicate decreased hazard, showing significantly more days before ICU discharge (coefficient, -0.3868; p < 0.0009) and hospital discharge (coefficient, -0.5507; p < 0.0001). Patient costs (coefficient, 0.0921; p = 0.1874) trend toward being lower in the new protocol. Readmission rates were significantly higher in the new protocol (coefficient, -1.1731; p = 0.0465), and death rates (coefficient, 0.0519; p = 0.9710) were comparable. CONCLUSIONS: Blunt liver and spleen injury patients treated under new American Pediatric Surgery Association guidelines compared with old guidelines had significant decreases in ICU and hospital LOS, a decreasing trend in costs, and comparable death rates but higher readmission rates. Future studies with larger sample sizes and detailed cost analysis would explore whether updated guidelines reduce patient costs and help elucidate the veracity or potential cause of the increased readmission rates. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level III.

The use of ectopic volar fibroblasts to modify skin identity.

Skin identity is controlled by intrinsic features of the epidermis and dermis and their interactions. Modifying skin identity has clinical potential, such as the conversion of residual limb and stump (nonvolar) skin of amputees to pressure-responsive palmoplantar (volar) skin to enhance prosthesis use and minimize skin breakdown. Greater keratin 9 (KRT9) expression, higher epidermal thickness, keratinocyte cytoplasmic size, collagen length, and elastin are markers of volar skin and likely contribute to volar skin resiliency. Given fibroblasts' capacity to modify keratinocyte differentiation, we hypothesized that volar fibroblasts influence these features. Bioprinted skin constructs confirmed the capacity of volar fibroblasts to induce volar keratinocyte features. A clinical trial of healthy volunteers demonstrated that injecting volar fibroblasts into nonvolar skin increased volar features that lasted up to 5 months, highlighting a potential cellular therapy.

Standoff photoacoustic detection of explosives using quantum cascade laser and an ultrasensitive microphone.

Standoff detections of explosives using quantum cascade lasers (QCLs) and the photoacoustic (PA) technique were studied. In our experiment, a mid-infrared QCL with emission wavelength near 7.35 µm was used as a laser source. Direct standoff PA detection of trinitrotoluene (TNT) was achieved using an ultrasensitive microphone. The QCL output light was focused on explosive samples in powder form. PA signals were generated and detected directly by an ultrasensitive low-noise microphone with 1 in. diameter. A detection distance up to 8 in. was obtained using the microphone alone. With increasing detection distance, the measured PA signal not only decayed in amplitude but also presented phase delays, which clearly verified the source location. To further increase the detection distance, a parabolic sound reflector was used for effective sound collection. With the help of the sound reflector, standoff PA detection of TNT with distance of 8 ft was demonstrated.

Cost-effective low timing jitter passively Q-switched diode-pumped solid-state laser with composite pumping pulses.

A novel scheme that combines gain switching with passive Q switching of a miniature diode-pumped solid-state laser is proposed and implemented. A composite pumping pulse, consisting of a long, low-intensity pulse and a following short, high-intensity pulse, is used to reduce the timing jitter. A greater-than-tenfold reduction in timing jitter is demonstrated.