Wearable Sensors Incorporating Compensatory Reserve Measurement for Advancing Physiological Monitoring in Critically Injured Trauma Patients.

Vital signs historically served as the primary method to triage patients and resources for trauma and emergency care, but have failed to provide clinically-meaningful predictive information about patient clinical status. In this review, a framework is presented that focuses on potential wearable sensor technologies that can harness necessary electronic physiological signal integration with a current state-of-the-art predictive machine-learning algorithm that provides early clinical assessment of hypovolemia status to impact patient outcome. The ability to study the physiology of hemorrhage using a human model of progressive central hypovolemia led to the development of a novel machine-learning algorithm known as the compensatory reserve measurement (CRM). Greater sensitivity, specificity, and diagnostic accuracy to detect hemorrhage and onset of decompensated shock has been demonstrated by the CRM when compared to all standard vital signs and hemodynamic variables. The development of CRM revealed that continuous measurements of changes in arterial waveform features represented the most integrated signal of physiological compensation for conditions of reduced systemic oxygen delivery. In this review, detailed analysis of sensor technologies that include photoplethysmography, tonometry, ultrasound-based blood pressure, and cardiogenic vibration are identified as potential candidates for harnessing arterial waveform analog features required for real-time calculation of CRM. The integration of wearable sensors with the CRM algorithm provides a potentially powerful medical monitoring advancement to save civilian and military lives in emergency medical settings.

The Preoperative Sinus CT: Avoiding a "CLOSE" Call with Surgical Complications.

Although functional endoscopic sinus surgery is an effective means of treating patients with recurrent and refractory sinusitis, the procedure is not without risk of serious surgical complications. Preoperative computed tomography (CT) affords radiologists the opportunity to prospectively identify anatomic variants that predispose patients to major surgical complications; however, these critical variants are not consistently evaluated or documented on preoperative imaging reports. The purpose of this review is to illustrate important anatomic variants and landmarks on the preoperative sinus CT with a focus on those that predispose patients to surgical complications. These critical variants and landmarks can be quickly recalled and incorporated into the preoperative imaging report through the use of the mnemonic "CLOSE": Cribriform plate, Lamina papyracea, Onodi cell, Sphenoid sinus pneumatization, and (anterior) Ethmoidal artery. This approach will greatly enhance the value of the preoperative imaging report for referring otolaryngologists and help reduce the risk of surgical complications. (©) RSNA, 2016 Online supplemental material is available for this article.

Establishment of the Clinician-Scientist Investigator Opportunity Network to Develop Military Medical Research Leaders.

INTRODUCTION: The ability of military clinicians to conduct military medical research is often limited because of competing priorities and a lack of research mentorship. The Clinician-Scientist Investigator Opportunity Network (CSION) was developed with the intent of training clinicians how to engage in requirements-driven research within the DoD. MATERIALS AND METHODS: Three to five academic medical faculties were selected from a pool of applicants each year to participate in a 2-year research fellowship. To be eligible for the CSION program, applicants had to meet the following criteria: (1) Completed residency graduate medical education training, (2) not be currently enrolled as a graduate medical education trainee, and (3) obtained permission from their department leadership to focus 25% of their duty hours on CSION participation to include didactic and research efforts. The remaining 75% of fellows' time was dedicated to clinical duties. Monthly didactics, intensive mentorship, and consistent support were offered to each fellow by the CSION leadership team. Metrics were recorded to include both research and clinical productivity. RESULTS: Between January 2019 and December 2022, 12 CSION fellows graduated from the program (four in the class of 2020, three in 2021, and five in 2022). From 2019 to 2021, the 12 CSION fellows initiated 204 research protocols, generated 489 publications/presentations, and secured 33 research grants. All graduates of the program remain active in clinical research with multiple graduates currently assigned to research positions. CONCLUSIONS: The CSION research education program is a 2-year additional duty research fellowship producing clinician-scientists conducting military-relevant medical research and publications and may be considered a low-cost/highly efficient alternative to achieve the reported benefits of the MD-PhD tract. The expansion of the CSION program may improve the quality of military medical research and health care.

Current approaches to diagnosis and management of rhinitis.

Rhinitis affects >20% of the population and is a common reason patients visit their primary care physician. Proper therapeutic intervention initially requires differentiating rhinitis from acute and chronic rhinosinusitis. After establishing rhinitis as the etiology of a patient's symptoms, a careful, thoughtful history and physical examination aids the cause. Rhinitis can be allergic, nonallergic, or mixed (having features of both allergic and nonallergic rhinitis). Therapeutic interventions vary, depending on the etiology of rhinitis. Symptoms that are refractory to avoidance and pharmacotherapy warrant referral to an allergist or otolaryngologist for consideration of immunotherapy or surgical intervention. In many cases, adhering to an evidence-based therapeutic treatment algorithm will allow physicians to effectively manage rhinitis.

Acute sinusitis.

Sinusitis is a common patient complaint that carries with it a large economic burden. It is one of the most common reasons patients visit their primary care physician. Acute bacterial rhinosinusitis (ABRS) can be distinguished from other forms of rhinosinusitis based on symptom duration of <4 weeks in a patient with purulent rhinorrhea associated with facial pain or pressure. Native upper aerodigestive tract bacteria are the most common etiologic agents. Treatment of ABRS is targeted primarily at symptom improvement. Amoxicillin can be used based on the clinical scenario and patient comorbidities. Computed tomographic scans are reserved for complicated presentations or when there is concern for intracranial extension or other complications. A systematic approach to ABRS will allow for improved patient quality of life and a decreased overall economic burden of this common entity.

Approaching chronic sinusitis.

Chronic sinusitis is a common disease that encompasses a number of syndromes that are characterized by sinonasal mucosal inflammation. Chronic sinusitis can be defined as two or more of the following symptoms lasting for more than 12 consecutive weeks: discolored rhinorrhea, postnasal drip, nasal obstruction, facial pressure or pain, or decreased sense of smell. Chronic sinusitis is further classified as chronic sinusitis with polyposis, chronic sinusitis without polyposis, or allergic fungal sinusitis using physical examination, and histologic and radiographic findings. Treatment methods for chronic sinusitis are based upon categorization of the disease and include oral and inhaled corticosteroids, nasal saline irrigations, and antibiotics in selected patients. Understanding the various forms of chronic sinusitis and managing and ruling out comorbidities are key to successful management of this common disorder.

The predictive utility of the 22-item sino-nasal outcome test (SNOT-22): A scoping review.

BACKGROUND: The 22-item sino-nasal outcome test (SNOT-22) is a widely used and powerful patient-reported outcomes measure for chronic rhinosinusitis (CRS). More recently; however, the SNOT-22 has been evaluated as a predictive tool for multiple conditions. The objective of this scoping review is to investigate the extent to which SNOT-22 is used in this manner and present this information in a way useful for clinicians. METHODS: A systematic search of PubMed, Scopus, Cochrane Library, and Web of Science was performed. Studies that evaluated SNOT-22s predictive utility were considered for eligibility in this scoping review. RESULTS: A total of 39 studies met eligibility. The SNOT-22 was found to be used as a predictive tool in three broad categories: (1) to predict a diagnosis, (2) to predict an outcome of an intervention, and (3) to predict a patient treatment preference. Thirteen studies were included in the diagnosis category, which made up ten different individual predictions. Twenty-four studies were included in the outcomes category and investigated 17 different individual predictions. Finally, two studies were included in the patient preferences category, which together made one prediction. CONCLUSIONS: The SNOT-22 is a versatile tool that has the potential to be used in predicting various diagnoses, outcomes, and patient preferences. However, care must be taken in applying these predictions to clinical practice, as further research must be done in validating these predictions based on SNOT-22 responses.

Local Effect of Ballistic Fragments Embedded Along the Carotid Sheath of a Porcine Animal Model.

INTRODUCTION: Energized ballistic fragments from improvised explosive devices were the most common cause of injury to coalition service personnel during conflicts in Iraq and Afghanistan. Surgical excision of retained fragments is not routinely performed unless there is a concern for injury to vital structures. However, no clear guidelines dictate when or if a fragment should be removed, reflecting a lack of objective evidence of their long-term effects. Using a porcine model, we aimed to evaluate changes to the carotid artery produced by retained fragments over time. MATERIALS AND METHODS: Institutional Animal Care and Use Committee approval for all experiments was obtained before commencement of the study. Eighteen female swine (mean mass 62.0 ± 3.4 kg) were randomized into three study groups corresponding to the time of survival after implantation of ballistic fragments: 1, 6, and 12 weeks. Two animals from each group were randomly assigned to have one of the three different fragments implanted within the right carotid sheath in zones 1-3 of the neck. The left carotid served as the control. The vascular flow rate and arterial diameter were measured at each level before implantation and again after the survival interval. Baseline and interval angiograms were performed to identify gross vascular changes. RESULTS: No abnormalities were identified on baseline or interval angiograms. No significant difference was found when the baseline was compared to interval measurements or when compared to the control side for all gross and physiological measures at 1 and 6 weeks (P = .053-.855). After 12 weeks, the flow and diameter changed significantly (P < .001-.03), but this significant change was found in both the control and affected carotid. CONCLUSIONS: The lack of significant gross anatomical and physiological changes at 6 weeks postimplantation lends evidence toward the current policy that early removal of retained ballistic fragments around cervical vessels is not required. Changes were significant after 12 weeks which suggest that surveillance may be required; however, such changes could be explained by physiological animal growth.

Battlefield Vital Sign Monitoring in Role 1 Military Treatment Facilities: A Thematic Analysis of After-Action Reviews from the Prehospital Trauma Registry.

INTRODUCTION: The Prehospital Trauma Registry (PHTR) captures after-action reviews (AARs) as part of a continuous performance improvement cycle and to provide commanders real-time feedback of Role 1 care. We have previously described overall challenges noted within the AARs. We now performed a focused assessment of challenges with regard to hemodynamic monitoring to improve casualty monitoring systems. MATERIALS AND METHODS: We performed a review of AARs within the PHTR in Afghanistan from January 2013 to September 2014 as previously described. In this analysis, we focus on AARs specific to challenges with hemodynamic monitoring of combat casualties. RESULTS: Of the 705 PHTR casualties, 592 had available AAR data; 86 of those described challenges with hemodynamic monitoring. Most were identified as male (97%) and having sustained battle injuries (93%), typically from an explosion (48%). Most were urgent evacuation status (85%) and had a medical officer in their chain of care (65%). The most common vital sign mentioned in AAR comments was blood pressure (62%), and nearly one-quarter of comments stated that arterial palpation was used in place of blood pressure cuff measurements. CONCLUSIONS: Our qualitative methods study highlights the challenges with obtaining vital signs-both training and equipment. We also highlight the challenges regarding ongoing monitoring to prevent hemodynamic collapse in severely injured casualties. The U.S. military needs to develop better methods for casualty monitoring for the subset of casualties that are critically injured.

Methylene blue enhances polyethylene glycol-fusion repair of completely severed rat sciatic nerves.

Complete transection of peripheral mixed nerves immediately produces loss of sensory perception, muscle contractions and voluntary behavior mediated by the severed distal axons. In contrast to natural regeneration (~1 mm/d) of proximal axons that may eventually reinnervate denervated targets, re-innervation is restored within minutes by PEG-fusion that consists of neurorrhaphy and a sequence of well specified hypo- and isotonic calcium-free or calcium-containing solutions, the anti-oxidant methylene blue (MB) and the membrane fusogen polyethylene glycol (PEG). In this study, we examined the relative efficacy of PEG-fusion with no MB (0%), 0.5% MB, or 1% MB on the recovery of voluntary behaviors by female Sprague-Dawley rats with a complete mid-thigh severance of their sciatic nerve bathed in extracellular fluid or calcium-containing isotonic saline. The recovery of voluntary behaviors is the most relevant measure of success of any technique to repair peripheral nerve injuries. We assessed recovery by the sciatic functional index, a commonly used measure of voluntary hindlimb behaviors following complete sciatic transections. We reported that both 1% MB and 0.5% MB in sterile distilled water in our PEG-fusion protocol with neurorrhaphy significantly increased the rate and extent of behavioral recovery compared to PEG plus neurorrhaphy alone. Furthermore, 0.5% MB was as effective as 1% MB in voluntary behavioral recovery as assessed by the sciatic functional index. Since sterile 1% MB is no longer clinically available, we therefore recommend that 0.5% MB be included in upcoming human clinical trials to evaluate the safety and efficacy of PEG-fusion. All animal procedures were approved by the University of Texas Institutional Animal Care and Use Committee (AUP-2019-00225) on September 9, 2020.

Neuroprotectin D1 Attenuates Blast Overpressure Induced Reactive Microglial Cells in the Cochlea.

OBJECTIVE/HYPOTHESIS: We examined a neuroinflammatory response associated with glial activation in the cochlea exposed to blast overpressure and evaluated the potential therapeutic efficacy of specialized pro-resolving mediators such as neuroprotectin D1, NPD1; (10R, 17S-dihydroxy-4Z, 7Z, 11E, 13E, 15Z, 19Z-docosahexaenoic acid) in a rodent blast-induced auditory injury model. STUDY DESIGN: Animal Research. METHODS: A compressed-air driven shock tube was used to expose anesthetized adult male Long-Evan rats to shock waves simulating an open-field blast exposure. Approximately 30 minutes after blast exposure, rats were treated with NPD1 (100 ng/kg body wt.) or vehicle delivered intravenously via tail vein injection. Rats were then euthanized 48 hours after blast exposure. Unexposed rats were included as controls. Tissue sections containing both middle and inner ear were prepared with hematoxylin-eosin staining to elucidate histopathological changes associated with blast exposure. Cochlear tissues were evaluated for relative expression of ionized calcium-binding adaptor 1 (Iba1), as an indicator of microglial activation by immunohistochemistry and western blot analyses. RESULTS: Our animal model resulted in an acute injury mechanism manifested by damage to the tympanic membrane, hemorrhage, infiltration of inflammatory cells, and increased expression of Iba1 protein. Moreover, therapeutic intervention with NPD1 significantly reduced Iba1 expression in the cochlea, suggesting a reduction of a neuroinflammatory response caused by blast overpressure. CONCLUSIONS: Blast overpressure resulted in an increased expression of proteins involved in gliosis within the auditory system, which were reduced by NPD1. Treatment of NPD1 suggests an effective strategy to reduce or halt auditory microglial cell activation due to primary blast exposure. LEVEL OF EVIDENCE: NA Laryngoscope, 131:E2018-E2025, 2021.

Unsuccessful frontal balloon sinuplasty for recurrent sinus barotrauma.

The standard of care treatment for diffuse recurrent sinus barotrauma (RSB) is an endoscopic sphenoethmoidectomy with a complete frontal dissection. Successful healing leaves the RSB patient with no ethmoid sinuses and endoscopically patent frontal, sphenoid, and maxillary ostia. In persistent cases, patients with small frontal ostia will go on to require a frontal drillout. Patients presenting for surgical management of RSB generally have minimal sinus disease despite significant symptoms during flight and the prospect of extensive surgical management can be unappealing. With the advent of balloon sinuplasty, military otolaryngologists anticipated this technology would permit therapeutic dilation of sinus ostia without the extensive surgical dissection and prolonged recovery typical for standard of care management. This case report is a cautionary note to the wider flight community to recognize a mechanism for recurrence of the underlying pathology when balloon sinuplasty is used that is not possible after properly performed standard of care sinus surgery for RSB.

Endoscopic frontal sinus drillout for recurrent barotrauma: a procedure to save a pilot's career.

INTRODUCTION: Complete sphenoethmoidectomy with a Draf IIA frontal dissection is the standard of care surgical management for medically resistant diffuse recurrent sinus barotrauma. Surgical failures still occur with this technique mainly due to the propensity of the frontal outflow tract to stenose. Endoscopic frontal revisions are notoriously prone to failure and historically represented the only option for aircrew afflicted by this career-ending complication of surgery. The frontal sinus drillout or endoscopic modified Lothrop procedure (EMLP) offers a highly successful salvage surgery for postoperative frontal ostium stenosis and is particularly suited to the physiologic requirements of the aviator. CASE: A high-performance aircraft pilot developed frontal stenosis after extensive sinus surgery for recurrent sinus barotrauma. Multiple failed endoscopic attempts to rehabilitate his sinuses finally gave way to success using the EMLP. He was returned permanently to flight duty at 6 wk post-op. DISCUSSION: This case report represents the first published successful application of the modified endoscopic Lothrop procedure to a pilot with recurrent frontal sinus barotrauma.

Is Skin the Most Allogenic Tissue in Vascularized Composite Allotransplantation and a Valid Monitor of the Deeper Tissues?

Since the 1960s, skin has been considered to be the most allogenic tissue in humans. This tenet has remained unquestioned in the reconstructive transplant arena, which has led to skin serving as the sole monitor for early rejection in vascularized composite allotransplantation. In this article, the authors question the validity of this belief. The authors' hypothesis is that skin is not always an accurate monitor of rejection in the deep tissues, thus questioning the positive and negative predictive value of the punch biopsy for suspected vascularized composite allotransplantation rejection. A search was carried out identifying vascularized composite allotransplantation publications where the allogenicity of transplanted skin was evaluated. Eighteen publications claimed skin was found to be the most allogenic tissue in humans, justifying its use as a superior monitor for rejection. Eight publications demonstrated skin to be a poor monitor of rejection deeper to the skin. Two vascularized composite allotransplantation animal studies reported skin rejecting simultaneously with the deeper tissues. Finally, three publications discussed a skin and kidney allograft, transplanted simultaneously, indicating skin allogenicity was equivalent to the that of the kidney allograft. Much of the literature in human vascularized composite allotransplantation claims skin to be an excellent monitor of the deep tissues. The conclusion from this study is that skin does not always function as a good monitor for what could be rejecting in the deep tissues. The authors believe continued research is necessary to focus on expanding novel monitoring techniques and technologies to accurately diagnose vascularized composite allotransplantation rejection without tissue destruction.

Postoperative Continuous Positive Airway Pressure Use and Nasal Saline Rinses After Endonasal Endoscopic Skull Base Surgery in Patients With Obstructive Sleep Apnea: A Practice Pattern Survey.

BACKGROUND: Endoscopic skull base surgery continues to evolve in its indications, techniques, instrumentation, and postoperative care. As surgery of the skull base will often violate dura, intraoperative and postoperative cerebrospinal fluid (CSF) leak is not uncommon and represents a potential conduit for air and bacterial contamination. Patients with obstructive sleep apnea (OSA) requiring continuous positive airway pressure (CPAP) therapy undergoing skull base surgery represent a challenging group. However, there appears to be a paucity of consensus regarding the postoperative management of this patient population. The objective of this study is to examine practice patterns and expert opinion on the use of postoperative CPAP and nasal saline in patients with OSA. METHODS: A 14-item survey was generated by consensus among expert authors and distributed online to members of the North American Skull Base society and other international skull base community members. Data were analyzed for median, mean, and standard deviation variables. Subgroup analysis was completed between surgeons from different geographical locations and operative experience. SPSS22 was utilized for all complex statistical analysis and figures. RESULTS: Seventy-one responses were collected from skull base surgeons. In patients with OSA, respondents would resume patients' CPAP therapy after a mean of 10.1 days (median, 7; standard deviation [SD], 10.2), without a CSF leak. In the presence of a small CSF leak, the mean duration would increase to 14.3 days (median, 14; SD, 9.8) and to 20.7 days (median, 21; SD, 11.8) in the presence of a larger leak. A surgeon's choice to attribute the relationship between delaying the start of nasal saline and CPAP after the endoscopic skull base surgery with progressively more challenging skull base repair was found to be statistically significant ( P < .001). CONCLUSION: Saline and CPAP therapies are initiated after the endoscopic skull base surgical repairs by surgeons at an increasing temporal delay in relation to the degree and complexity of the skull base defect repaired.

Construct validity of a low-cost medium-fidelity endoscopic sinus surgery simulation model.

OBJECTIVE: Assess construct validity of a low-cost medium-fidelity silicone injection molded model task trainer for endoscopic sinus surgery (ESS) training. METHODS: Fellowship-trained rhinologists, otolaryngology attendings, and otolaryngology residents at various levels of training performed sinus endoscopy and seven procedures on the model. Construct validity was evaluated by comparing novice to various levels of experienced performance using a validated checklist. RESULTS: Thirty-two subjects participated in this study. Otolaryngology attendings and postgraduate year (PGY) 3 to 5 otolaryngology residents significantly outperformed PGY 1 to 2 otolaryngology residents on most tasks in the task-specific checklist. CONCLUSIONS: This study demonstrated the construct validity of the low-cost medium-fidelity ESS model. LEVEL OF EVIDENCE: NA Laryngoscope, 129:1505-1509, 2019.

International assessment of inter- and intrarater reliability of the International Frontal Sinus Anatomy Classification system.

BACKGROUND: Inconsistencies in the nomenclature of structures of the frontal sinus have impeded the development of a validated "reference standard" classification system that surgeons can reliably agree upon. The International Frontal Sinus Anatomy Classification (IFAC) system was developed as a consensus document, based on expert opinion, attempting to address this issue. The purposes of this study are to: establish the reliability of the IFAC as a tool for classifying cells in the frontal recess among an international group of rhinologists; and improve communication and teaching of frontal endoscopic sinus surgery (ESS). METHODS: Forty-two computed tomography (CT) scans, each with a marked frontal cell, were reviewed by 15 international fellowship-trained rhinologists. Each marked cell was classified into 1 of 7 categories described in the IFAC, on 2 occasions separated by 2 weeks. Inter- and intrarater reliability were evaluated using Light's kappa (κ), the interclass correlation coefficient (ICC), and simple proportion of agreement. RESULTS: Interrater reliability showed pairwise κ values ranging from 0.7248 to 1.0, with a mean of 0.9162 (SD, 0.0537). The ICC was 0.98. Intrarater reliability showed κ values ranging from 0.8613 to 1.0, with a mean of 0.9407 (SD, 0.0376). The within-rater ICC was 0.98. CONCLUSION: Among a diverse sample of rhinologists (raters), there was substantial to almost perfect agreement between raters, and among individual raters at different timepoints. The IFAC is a reliable tool for classification of cells in the frontal sinus. Further outcome studies are still needed to determine the validity of the IFAC.

Isolated posterior table frontal sinus fractures do not form mucoceles in a goat model.

OBJECTIVE: The goal of this study was to investigate how patency of the nasofrontal outflow tract would affect frontal sinus healing in the setting of displaced, comminuted, posterior table fractures in the adult goat (Capra hircus). STUDY DESIGN: Prospective animal study. SUBJECTS AND METHODS: Posterior table fractures were created in 20 adult goats. The nasofrontal outflow tract was left patent in 10 goats (Group 1) and obstructed in 10 (Group 2). Gross, radiologic, and histologic evaluation were carried out six months postoperatively. RESULTS: One of nine subjects subjects (11%) in Group 1 developed a mucocele while eight of 10 (80%) in Group 2 developed mucoceles (P = 0.004). No subjects (100%) in Group 1 had gross, radiologic, or histologic evidence of mucosal ingrowth into the posterior table, while two of 10 (20%) in Group 2 showed evidence of mucosal ingrowth into, but not through, the posterior table. In both groups 100% of the subjects had gross and histologic evidence of intact posterior tables abutting the dura. CONCLUSION: An occluded nasofrontal outflow tract leads to an increased mucocele formation rate at six months. In an unobstructed nasofrontal outflow tract there is no gross, radiologic, or histologic evidence of mucosal ingrowth into the posterior table at six months. These findings would suggest that not all comminuted, significantly displaced posterior table fractures need to be surgically addressed if the nasofrontal outflow tract is patent.

Aerosinusitis: pathophysiology, prophylaxis, and management in passengers and aircrew.

Patients presenting before flight with an upper respiratory infection are at risk for aerosinusitis. Prophylaxis of this condition consists of an oral decongestant before flight and nasal decongestant spray during the flight just prior to descent. Evaluation of the patient presenting with aerosinusitis consists of a careful physical exam with emphasis on diagnosing treatable nasal and sinus pathology. Categorization of the patient into the Weissman classification is important for determining prognostic factors for recovery. Management of this condition is based on the Weissman stage. Stage I or II lesions are generally treated conservatively with a 1-wk course of topical sprays, analgesics, a tapering course of steroids, and oral decongestants. Use of antibiotics is reserved for those cases initiated by bacterial sinusitis. Additionally, antihistamines are reserved for cases where allergies were the inciting cause. Stage III lesions are rarely seen in civilian air travelers due to the relatively low fluctuations in ambient air pressure. Aircrew that suffer Stage III aerosinusitis are at risk for recurrent sinus barotrauma that may require an expertly performed functional endoscopic sinus surgery to successfully manage it.