Airway management is at the forefront for combat medics dealing with battlefield trauma. For military service members, compromised airways are the second leading cause of potentially survivable death on the battlefield, accounting for one in ten preventable combat deaths. Effective suction is a critical component of airway clearance. However, currently available devices are too heavy and bulky to be carried by combat medics and are insufficiently powered. The industry has not responded to the need, with companies continuing to produce models using 1970s technology. A literature review was completed with the assistance of a librarian. The databases searched included: Biomedical Research Database (BRD), Computer Retrieval of Information of Scientific Projects (CRISP), Federal Research in Progress (FEDRIP), Defense Technical Information Center (DTIC), Pub Med/Medline, and OVID. Additionally, a Google Scholar search was performed to identify nonstandard sources. After screening, a total of 40 articles were used. There were no randomized controlled trials or other high-quality evidence that addressed the issues; there was limited peer-reviewed literature on the use, effectiveness, adverse effects, and safety of suction for use in combat casualty care. A review of the available literature revealed no standards, either proposed, validated, or accepted, for the safety or avoidance of adverse effects for portable suction device use in combat casualty care. Similarly, there are no accepted standards to guide the safe use and anticipated adverse effects of suction for use in prehospital combat or emergency care. Nevertheless, there are meaningful data that can be extracted from the few studies available combined with non-clinical studies, narrative reviews and case reports, and expert opinions.

Airway clearance is a foremost priority for combat medics dealing with battlefield trauma. This life saving intervention starts with inspection, clearing any obstructions from the airway, and if necessary, placement of an endotracheal tube to secure the airway. For inspecting and clearing the airway under complicated battlefield conditions, combat medics require a portable suction device that is compact, lightweight, rugged, and capable of rapidly evacuating a mix of liquid and solid particles, which may include bone fragments or broken teeth. While several portable suction devices are available on the market, none were developed specifically for the combat environment. Interviews with combat medics and other relevant personnel revealed that currently available systems are limited in utility to the point of often being intentionally omitted from their kits. In addition, these discussions identified several design specifications for a desired system, such as size (30 × 10 × 10 cm), weight (≤1 kg), fluid flowrate (1 L/min), and canister size (0.5–1 L), among others. This research focused on developing and characterizing a functional prototype within the specified design criteria. After designing and fabricating the device, evacuation of water, blood mimicking solution, and simulated vomitus solution were assessed. In addition, a comparative analysis was carried out between the five different commercially available suction catheters by assessing fluid flow rate and obstruction resistance. The results demonstrate the first proof-of-concept characterization for a novel combat-oriented suction system and provide a basis for comparing the performance of suction systems and catheters used in airway management.

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Background: Photothermal therapies have shown promise for treating pancreatic ductal adenocarcinoma when they can be applied selectively, but off-target heating can frustrate treatment outcomes. Improved strategies leveraging selective binding and localized heating are possible with precision medical approaches such as functionalized gold nanoparticles, but careful control of optical dosage and thermal generation would be imperative. However, the literature review revealed many groups assume liver properties for pancreas tissue or rely on insufficiently rigorous characterization studies. Objective: The objective of this study was to determine the thermal conductivity and optical properties at 808/1064 nm wavelengths in healthy samples of fresh and frozen porcine pancreas ex vivo. Methods: Thermal conductivity of the porcine pancreas tissue was measured by utilizing a hot plate and two K-type thermocouples. Experimental variables such as tissue sample thickness, hot plate temperature, and heat convection coefficient were estimated through the control experiments utilizing specimens with known thermal conductivity. Optical evaluations assessed light attenuation at the 808 and 1064 nm wavelengths (continuous wave, collimated beam) by measuring the light transmittance and reflectance of different tissue thicknesses. In turn, these measurements were input into an inverse adding-doubling program to estimate the optical absorption and reduced scattering coefficients. Results: Interestingly, pancreas tissue thermal conductivity was demonstrated to have no significant difference (p > 0.5) between samples that were fresh, frozen for 7 days, or frozen for 14 days. Conversely, optical property assessment exhibited a significant difference (p < 0.001) between fresh and frozen tissue samples, with increased absorbance and reflectance within the frozen group. However, the optical attenuation values measured were substantially less than that of the liver or reported in previous pancreas studies, suggesting a wide overestimation of these properties. Conclusions: These thermal and optical properties are critical to the development of novel therapeutic strategies like plasmonic photothermal therapy, but perhaps more importantly, are invaluable towards informing better surgical planning and operative technique among the existing thermal approaches for treating pancreas tissue. K E Y W O R D Sabsorption coefficient, fresh versus frozen porcine pancreas tissue, porcine pancreas optical properties, porcine pancreas thermal conductivity, scattering coefficient

Plasmonic photothermal therapy (PPTT) has potential as a superior treatment method for pancreatic cancer, a disease with high mortality partially attributable to the currently non-selective treatment options. PPTT utilizes gold nanoparticles infused into a targeted tissue volume and exposed to a specific light wavelength to induce selective hyperthermia. The current study focuses on developing this approach within an ex vivo porcine pancreas model via an innovative fiberoptic microneedle device (FMD) for co-delivering light and gold nanoparticles. The effects of laser wavelengths (808 vs. 1064 nm), irradiances (20–50 mW·mm−2), and gold nanorod (GNR) concentrations (0.1–3 nM) on tissue temperature profiles were evaluated to assess and control hyperthermic generation. The GNRs had a peak absorbance at ~800 nm. Results showed that, at 808 nm, photon absorption and subsequent heat generation within tissue without GNRs was 65% less than 1064 nm. The combination of GNRs and 808 nm resulted in a 200% higher temperature rise than the 1064 nm under similar conditions. A computational model was developed to predict the temperature shift and was validated against experimental results with a deviation of <5%. These results show promise for both a predictive model and spatially selective, tunable treatment modality for pancreatic cancer.