Arterial Occlusion Effectiveness of Space Blanket‒Improvised Tourniquets for the Remote Setting.

INTRODUCTION: Control of severe extremity hemorrhage by tourniquet can save lives. In remote areas or in mass casualty incidents with multiple severely bleeding victims, lack of conventional tourniquets may make it necessary to improvise tourniquets. METHODS: Occlusion of the radial artery and delayed onset of capillary refill time resulting from windlass-type tourniquets were experimentally investigated by comparing a commercial tourniquet and a space blanket‒improvised tourniquet with a carabiner as a rod. This observational study was conducted on healthy volunteers in optimal application circumstances. RESULTS: Operator-applied Combat Application Tourniquets were deployed more swiftly (27 s, 95% CI: 25.7-30.2 vs 94 s, 95% CI: 81.7-114.4) and achieved 100% complete radial occlusion compared with improvised tourniquets, as assessed by Doppler sonography (P<0.001). When space blanket‒improvised tourniquets were used, traces of radial perfusion persisted in 48% of the applications. In Combat Application Tourniquets, capillary refill times were significantly delayed (7 s, 95% CI: 6.0-8.2 vs 5 s, 95% CI: 3.9-6.3) compared with those when using improvised tourniquets (P=0.013). CONCLUSIONS: Improvised tourniquets should be considered only in dire circumstances with uncontrolled extremity hemorrhage and when no commercial tourniquets are available. Complete arterial occlusion was achieved in only half of the applications using a space blanket‒improvised tourniquet when a carabiner was used as a windlass rod. The speed of application was inferior to that for Combat Application Tourniquets. Similar to Combat Action Tourniquets, the correct assembly and application of space blanket‒improvised tourniquets on upper and lower extremities have to be trained. TRIAL REGISTRATION: ClinicalTrials.gov identifier: BASG No.: 13370800/15451670.

Rescue Blankets as Multifunctional Rescue Equipment in Alpine and Wilderness Emergencies-A Narrative Review and Clinical Implications.

The utilization of rescue blankets in pre-hospital emergency medicine exceeds protection from hypothermia and enhanced visibility by far. In this narrative review, we focus on emphasizing the alternative applications of these fascinating multifunctional tools in the pre-hospital setting. A literature search in PubMed® and Web of ScienceTM yielded 100 results (last update was on 8 July 2022), a total number of 26 of which were included in this narrative review. Nine articles assessing alternative functions of rescue blanket were further evaluated and described in more detail. In addition, we performed various experimental and observational trials to test the functionality of rescue practice in mountain emergency medicine. Newly fabricated rescue blankets proved to possess impressive robustness. We evaluated rescue blankets in their applicability to not only protect from hypothermia, but also as practical tools to treat catastrophic hemorrhage and bleeding limbs, to perform open pneumothorax chest seals in sucking chest wounds, to prevent damage to unprotected eyes on the glacier and as alternative instruments for transportation in the inaccessible areas. Rescue blankets are important rescue equipment in alpine and wilderness emergencies with multifunctional applications, and must be part of every personal medical kit.

Electromagnetic Interference from Heated Gloves May Compromise Avalanche Transceiver Function.

INTRODUCTION: Rapid location of avalanche victims by companions using avalanche transceivers is of utmost importance to prevent asphyxiation. The objective was to determine whether electromagnetic interference from heating elements in gloves worn by rescuers or victims can impair the receiving or transmitting function of avalanche beacons. METHODS: Commercially available heated gloves from 3 different manufacturers were examined during a simulated search with 3 common brands of avalanche transceivers. Distance to target beacon at first signal detection and accuracy of direction to target, as indicated by the arrow from the direction indicator, were evaluated. RESULTS: Preliminary tests showed that transmitting and receiving signals are degraded by electromagnetic interference caused by rectangular pulses emitted by activated heating elements. Field tests revealed significantly reduced distances of first signal detection when heated gloves were turned on near receiving avalanche transceivers (P<0.001; Wilcoxon signed-rank test). Decreased distance to target beacon ranged between 1.9 m (5%) and 41.5 m (94%) at first detection, depending on the avalanche transceiver used. CONCLUSIONS: Avalanche transceivers are susceptible to electromagnetic interference from gloves with electric heating elements. We do not recommend using heated gloves when performing a transceiver search for avalanche victims because it can lead to a delay in rescue.

Thin foil body-shield resuscitation barrier device to protect from blood: an experimental study.

In times of collective concern about pandemics, body-shield resuscitation barrier devices are more and more considered to protect against transmission of different pathogens between rescuers and patients. The objective of this experimental study was to investigate the characteristics of blood drops dispersed on the surface of four different foils suitable for blanketing patients during resuscitation. We analyzed run-off characteristics of blood stains depending on surface properties of polyvinyl chloride, polyethylene, polyethylene terephthalate and aluminum-coated polyethylene terephthalate. Confocal fluorescence microscopy revealed less cellular density and lack of fibrin networks in blood stains on the four foil surfaces than on paper towel. Delayed clotting went along with larger areas of contamination indicating a greater likelihood of coming into contact with potential germs but a smaller chance of contracting an infection. Space blankets as obligatory components of first aid kits are readily available for rescuers and serve as a mechanical barrier between rescuers and patients during resuscitation.

Rescue blankets as multifunctional rescue equipment in alpine and wilderness emergencies: a commentary.

Emergency applications of rescue blankets go far beyond protection from hypothermia. In this review alternative applicabilities of these remarkable multifunctional tools were highlighted. Newly fabricated rescue blankets prove impressive robustness. The high tensile strength along with its low weight enable further applications, e.g. immobilization of injured extremities, splinting, wound dressing, a makeshift chest seal in sucking chest wounds, amongst others. Furthermore, the foil can be used as a vapour barrier, as eye protection and it can even be used to construct a stopgap bivouac sack, as alternative tool for transportation in the remote area and a wind shield or a water reservoir in the wilderness. During search-and-rescue missions the light reflection from the gold surface enhances visibility and increases the chance to be found. Rescue blankets are essential parts of first aid kits and backpacks in alpine and wilderness environment with multifunctional applicabilities. In this commentary to a review we want to evaluate the numerous applicabilities of rescue blankets in the treatment of emergencies by wilderness medicine and pre-hospital EMS.

Rescue Blanket as a Provisional Seal for Penetrating Chest Wounds in a New Ex Vivo Porcine Model.

BACKGROUND: Open pneumothorax after a penetrating thorax trauma is a life-threatening disease with high mortality. An emergency application of a chest seal (CS) allowing the release of trapped air is the optimum initial therapy until surgical chest drainage is available. METHODS: In a newly developed experimental porcine model of open pneumothorax, we tested 3 different materials regarding their applicability for acute treatment of sucking chest wounds in prehospital emergency care, namely a commonly used rescue blanket (RB), plastic foil from a gauze package (packing material), and a commercial CS. RESULTS: An ex vivo open pneumothorax model using a porcine chest wall and a vacuum-assisted drainage system was successfully established. RB segments sized 70 × 100 mm achieved significantly higher rates of successful sealing than plastic foils from a gauze package sized 100 × 100 mm when the devices were applied to the moistened chest wall and fixed on 3 sides (5/5 [100%] vs 0/5 [0%], respectively; P = .002). Loosely fixed RBs efficiently released injected air (10/10 [100%]) and consequently sealed the wound in all cases (10/10). CONCLUSIONS: RBs, applied wet, are appropriate CSs with good occlusive and adherence properties. Fixation on 2 sides of the dressing is sufficient to allow trapped air to exit while providing appropriate sealing of the chest wound. RBs were superior to plastic foils from a gauze package and were seen to function as a potent makeshift CS when no commercial CS is available.

Barrier resuscitation by lay rescuers during COVID-19 pandemic.

Aerosols generated from chest compressions and ventilation attempts in patients with cardiac arrest may cause airborne infections. Accordingly, the interim international resuscitation guidelines have restricted basic life support by lay rescuers to compression only and the use of an automated external defibrillator during the COVID-19 pandemic. Although these measures may diminish the risk of infection for laypersons, the missing respiratory support can be detrimental for patients with hypoxia-related cardiac arrest. To overcome this shortcoming we want to introduce a special tool that allows ventilation during barrier resuscitation by laypersons. We hypothesize that the application of a device made of a polyvinyl chloride shield with a centrally installed S-shaped ventilation pipe with integrated filter can provide adequate ventilation while concurrently protecting patient and rescuer from airborne agents. Aerosols from air leakage are removed by adhesion and drainage below the barrier. No specific training other than basic life support is needed. We suggest that a tool of this kind be considered essential equipment and stored together with disposable gloves in public access locations.

High Tensile Strength Increases Multifunctional Use of Survival Blankets in Wilderness Emergencies.

INTRODUCTION: Metallic survival blankets are multifunctional medical devices frequently used to provide thermal insulation in sport and leisure activities and in emergency care. To assess further properties of survival blankets, we investigated their breaking strength under laboratory conditions. METHODS: An experimental study was performed with 2 commercially available survival blankets used by emergency medical services. Breaking strength measured with a tensile testing machine was determined consecutively with 10 tests conducted per brand. RESULTS: Breaking strength (mean±SD) of the tested brands was 3.8±0.4 kN, (range: 2.8-4.1 kN) and 4.0±0.5 kN (range: 3.2-4.6 kN). When using the windlass of a commercially available tourniquet for the longitudinally folded survival blanket, the windlass bent at a force of 0.8 kN; when using a carabiner, the force exceeded 3.6 kN before failure occurred in both blanket brands. CONCLUSIONS: Both brands of survival blankets show impressive tensile strength, indicating that they have the potential to serve as temporary pelvic binders or even as makeshift tourniquets when urgent bleeding control is needed.

High-energy visible light transparency and ultraviolet ray transmission of metallized rescue sheets.

Metallized rescue sheets are essential components in first aid boxes and professional emergency equipment for provision of thermal insulation. We investigated the transparency for visual light and the transmission of ultraviolet radiation and high-energy visible light in the violet/blue band of rescue sheets under laboratory conditions to evaluate the potential of blocking solar radiation during outdoor activities. An experimental study was performed using two commercially available brands of rescue sheets. Transmission of visible light and ultraviolet light was assessed by optometry. Single-layer transparency for visible light was between 1% and 8%. Transmission for high-energy visible light in the violet/blue band and ultraviolet A rays was between 1% and 13% for the single layer and between 0% and 3% for the double layer of the rescue sheets. Transmission for ultraviolet B rays afforded by each tested rescue sheet brand was between 0% and 1% for the single layer. Double-layer rescue sheets blocked 100% of ultraviolet B radiation. In conclusion, single layer rescue sheets were sufficiently permeable for visible light and diminished transmission for ultraviolet radiation and high-energy visible light in the violet/blue band to potentially protect from solar radiation if used for facial protection and as makeshift sun googles.