Auditory System Injury on the Battlefield-Solutions for Point-of-Injury and Prolonged Casualty Care: A DOTmLPF-P Analysis.

INTRODUCTION: "Good hearing" (DoDI 6030.03 6.5&6.6) is a combat multiplier, critical to service members' lethality and survivability on the battlefield. Exposure to an explosive blast or high-intensity continuous noise is common in operational settings with the potential to compromise both hearing and vestibular health and jeopardize safety and high-level mission performance. The Joint Trauma System Acoustic Trauma Clinical Practice Guideline was published in 2018, providing recommendations for the assessment and treatment of aural blast injuries and acoustic trauma in the forward deployed environment. Combat care capabilities responsive to current threat environments emphasize prolonged casualty care. Despite recommendations, auditory system health has not been assessed routinely or in its entirety on the battlefield. This is due primarily to the large footprint of an audiometric booth and to the heavy logistical burden of providing high-quality, comprehensive auditory system (including vestibular) examinations in the combat environment. MATERIALS AND METHODS: The Defense Health Agency Hearing Center of Excellence has completed a Doctrine, Organization, Training, Materiel, Leadership & Education, Personnel, Facilities, and Policy (DOTmLPF-P) analysis of battlefield auditory system assessment and treatment, using 67 existing DoD documents and artifacts related to operational medicine. RESULTS: Our analysis found that acoustic trauma is generally not addressed in any of the DOTmLPF-P domains. We recommend that auditory system assessment and treatment be incorporated across the continuum of care on the battlefield. This should be addressed through Prolonged Field Care and Tactical Combat Casualty Care guidance and in all Tactical Combat Casualty Care training programs. Equipment sets should be modified to include boothless technology and associated materiel for auditory system assessment. Policy and Doctrine changes would be required to mandate and support the implementation of these services. Uniformed audiologists should be added to the organizational structure at role 3 or higher to provide direct patient care; consult with other health care providers and commanders; develop and support enforcement of noise hazard guidelines; track hearing readiness; and, when necessary, provide specialized hearing protection devices that can compensate for hearing loss. CONCLUSIONS: These recommendations aim to help the DoD bring about necessary assessments and interventions for acoustic trauma so that service members can have better hearing outcomes and maintain critical auditory system function on the battlefield.

Heritage of army audiology and the road ahead: the Army Hearing Program.

Noise-induced hearing loss has been documented as early as the 16th century, when a French surgeon, Ambroise Paré, wrote of the treatment of injuries sustained by firearms and described acoustic trauma in great detail. Even so, the protection of hearing would not be addressed for three more centuries, when the jet engine was invented and resulted in a long overdue whirlwind of policy development addressing the prevention of hearing loss. We present a synopsis of hearing loss prevention in the US Army and describe the current Army Hearing Program, which aims to prevent noise-induced hearing loss in soldiers and to ensure their maximum combat effectiveness.

Grade III ischemia on presentation with acute myocardial infarction predicts rapid progression of necrosis and less myocardial salvage with thrombolysis.

We assessed the relation between baseline electrocardiographic ischemia grades and initial myocardial area at risk (AR) and final infarct size (IS) in 49 patients who had undergone (99m)Tc sestamibi single-photon emission computed tomography before and 6 +/- 1 days after thrombolysis. Patients were classed as having grade III ischemia (ST segment elevation with terminal QRS distortion, n = 19) or grade II ischemia (ST elevation but no terminal QRS distortion, n = 30). We compared AR and IS by baseline ischemia grade and treatment (adenosine vs. placebo) and assessed relations of infarction index (IS/AR ratio x100) to time to thrombolysis, baseline ischemia grade, and adenosine therapy. Time to thrombolysis was similar for grade II and grade III. For placebo- treated patients, the median AR did not differ significantly between grade II (38%) and grade III patients (46%, p = 0.47), nor did median IS (16 vs. 40%, p = 0.096), but the median infarction index was 66 vs. 90% (p = 0.006). For adenosine-treated patients, median AR (21 vs. 26%, p = 0.44), median IS (5 vs. 17%, p = 0.15), and their ratio (31 vs. 67%, p = 0.23) did not differ significantly between grade II and grade III patients. The infarction index independently related to grade III ischemia (p = 0.0121) and adenosine therapy (p = 0.045). Infarct size related to baseline ischemia grade and was reduced by adenosine treatment. Necrosis progressed slowlier with baseline grade II versus III ischemia, which could offer more time for myocardial salvage with reperfusion.