A Novel 3D-Printed Gravity-Independent Air-Eliminating Filter for Rapid Intravenous Infusions.

INTRODUCTION: The absence of a consistent downward G vector can make separation of gases from liquids challenging, such as in field medicine without stable upright equipment or during spaceflight. This limits the use of medical equipment and procedures like administration of intravenous (IV) fluids in microgravity and can make field medicine hazardous. Administering IV fluids and medications in microgravity requires a technique to separate air from the liquid phase. Current commercial filters for separation of gases are incompatible with high flow and blood. We present a novel filter designed to provide adequate air clearance without a consistent downward G vector.METHODS: Inline air-eliminating filters were designed for use with IV fluid tubing in microgravity using computer-aided design software and printed using nylon 12 on an EOS Selective Laser Sintering 3D printer. A 0.2-µm membrane filter was adhered around a central, hollow pillar with external spiral baffles allowing separation and venting of air from the fluid. Results were compared against commercially available inline air-eliminating filters.RESULTS: The 3D-printed filters outperformed the commercial filters in both percentage of air removed and flow rates. The centrifugal, baffled filter had flow rates that far exceeded the commercial filters during rapid transfusion.DISCUSSION: IV fluid administration is an often underappreciated and a necessary basic requirement for medical treatment. An air-eliminating filter compatible with blood and rapid transfusion was developed and validated with crystalloid solutions to allow the successful administration of IV fluid and medication without a consistent downward G vector.Formanek A, Townsend J, Ottensmeyer MP, Kamine TH. A novel 3D-printed gravity-independent air-eliminating filter for rapid intravenous infusions. Aerosp Med Hum Perform. 2024; 95(6):327-332.

Effects of whole-body vibration or resistive-vibration exercise on blood clotting and related biomarkers: a systematic review.

Whole-body vibration (WBV) and resistive vibration exercise (RVE) are utilized as countermeasures against bone loss, muscle wasting, and physical deconditioning. The safety of the interventions, in terms of the risk of inducing undesired blood clotting and venous thrombosis, is not clear. We therefore performed the present systematic review of the available scientific literature on the issue. The review was conducted following the guidelines by the Space Biomedicine Systematic Review Group, based on Cochrane review guidelines. The relevant context or environment of the studies was "ground-based environment"; space analogs or diseased conditions were not included. The search retrieved 801 studies; 77 articles were selected for further consideration after an initial screening. Thirty-three studies met the inclusion criteria. The main variables related to blood markers involved angiogenic and endothelial factors, fibrinolysis and coagulation markers, cytokine levels, inflammatory and plasma oxidative stress markers. Functional and hemodynamic markers involved blood pressure measurements, systemic vascular resistance, blood flow and microvascular and endothelial functions. The available evidence suggests neutral or potentially positive effects of short- and long-term interventions with WBV and RVE on variables related to blood coagulation, fibrinolysis, inflammatory status, oxidative stress, cardiovascular, microvascular and endothelial functions. No significant warning signs towards an increased risk of undesired clotting and venous thrombosis were identified. If confirmed by further studies, WBV and RVE could be part of the countermeasures aimed at preventing or attenuating the muscular and cardiovascular deconditioning associated with spaceflights, permanence on planetary habitats and ground-based simulations of microgravity.

A 3D-Printed Portable Sterilizer to Be Used During Surgical Procedures in Spaceflight.

INTRODUCTION: During spaceflight, it is important to consider the mechanisms by which surgeries and medical procedures can be safely and efficiently conducted. Instruments used to carry out these processes need to be sterilized. Thus, we have designed and tested a three-dimensional-printed (3D-printed) portable sterilizer that implements far ultraviolet-C (Far UV-C) light radiation to disinfect bacteria and microorganisms from surgical instruments.METHODS: The sterilizer was 3D-printed with polylactic acid filament. Effectiveness was assessed through three trials at differing times of sterilization and compared against a control group of no sterilization and against Clorox wipes. Cultures were incubated on agar dishes and counted with ImageJ.RESULTS: Increasing time under Far UV-C light radiation increased the percentage of sterilization up to 100% at 10 min. The 3D-printed sterilizer was significantly better than Clorox wipes and control.DISCUSSION: As sterilization will be necessary for surgical procedures in microgravity and upmass is a significant concern, we have successfully demonstrated a 3D-printable portable sterilizer for surgical instruments that achieves 100% success in using Far UV-C light to disinfect its surface of bacteria with a 10-min sterilizing time. Further research is necessary to test this design in microgravity and with differently sized and shaped instruments.Kovalski E, Salazar L, Levin D, Kamine TH. A 3D-printed portable sterilizer to be used during surgical procedures in spaceflight. Aerosp Med Hum Perform. 2023; 94(11):857-860.

Characteristics of acute sexual assault care in New England emergency departments.

Objective: Interventions such as written protocols and sexual assault nurse examiner programs improve outcomes for patients who have experienced acute sexual assault. How widely and in what ways such interventions have been implemented is largely unknown. We sought to characterize the current state of acute sexual assault care in New England. Methods: We conducted a cross-sectional survey of individuals acute with knowledge of emergency department (ED) operations in relation to sexual assault care at New England adult EDs. Our primary outcomes included the availability and coverage of dedicated and non-dedicated sexual assault forensic examiners in EDs. Secondary outcomes included frequency of and reasons for patient transfer; treatment before transfer; availability of written sexual assault protocols; characteristics and scope of practice of dedicated and non-dedicated sexual assault forensic examiners (SAFEs), provision of care in SAFEs' absence; availability, coverage, and characteristics of victim advocacy and follow-up resources; and barriers to and facilitators of care. Results: We approached all 186 distinct adult EDs in New England to recruit participants; 92 (49.5%) individuals participated, most commonly physician medical directors (n = 34, 44.1%). Two thirds of participants reported they at times have access to a dedicated (n = 52, 65%, 95% confidence interval [CI], 54.5%-75.5%) or non-dedicated (n = 50, 64.1%; 95% CI, 53.5%-74.7%) SAFE, but fewer reported always having this access (n = 9, 17.3%; 95% CI, 7%-27.6%; n = 13, 26%; 95% CI, 13.8%-38.2%). We describe in detail findings related to our secondary outcomes. Conclusions: Although SAFEs are recognized as a strategy to provide high-quality acute sexual assault care, their availability and coverage is limited.

Impact of Telemedicine on Extended Focused Assessment With Sonography for Trauma Performance and Workload by Critical Care Transport Personnel.

INTRODUCTION: There are currently no reports on whether telementoring for extended focused assessment with sonography for trauma (eFAST) improves critical care transport providers' performance in prehospital settings. Our objective was to determine the impact of teleguidance on eFAST performance and quantify workload experience. METHODS: Eight trauma injury modules were selected on simulated patients. Critical care transport (CCT) providers were tasked to complete one independent and one emergency physician-telementored eFAST. The time to completion and the percent of correct findings were obtained. Participants completed the NASA Task Load Index after each iteration to assess workload. RESULTS: Eight independent and 8 telementored eFASTs were completed. The mean times to complete the independent and telementored eFAST were 5 minutes 16 seconds (95% confidence interval [CI], 3 minutes 32 seconds, 6 minutes 59 seconds) and 8 minutes 27 seconds (95% CI, 5 minutes 14 seconds, 11 minutes 39 seconds), respectively (P = .06). The percentage of correctly identified injuries for the independent versus the teleguided eFAST was 65% versus 92.5% (P = .01). The CCT providers experienced higher mental (P = .004), temporal (P = .01), and effort (P = .004) demands; greater frustration (P = .001); and subjective lower performance (P = .003) during independent trials. The emergency physician experienced higher mental (P = .001), temporal (P = .02), effort (P = .005), and frustration (P = .001) demands than the CCT members. CONCLUSION: The teleguided eFAST yielded higher accuracy than the independent eFAST. The CCT providers relied on teleguidance of the remote physician when performing the eFAST. Teleguidance may improve the accuracy of ultrasounds performed by prehospital personnel in real-life scenarios.

Pathophysiology, risk, diagnosis, and management of venous thrombosis in space: where are we now?

The recent incidental discovery of an asymptomatic venous thrombosis (VT) in the internal jugular vein of an astronaut on the International Space Station prompted a necessary, immediate response from the space medicine community. The European Space Agency formed a topical team to review the pathophysiology, risk and clinical presentation of venous thrombosis and the evaluation of its prevention, diagnosis, mitigation, and management strategies in spaceflight. In this article, we discuss the findings of the ESA VT Topical Team over its 2-year term, report the key gaps as we see them in the above areas which are hindering understanding VT in space. We provide research recommendations in a stepwise manner that build upon existing resources, and highlight the initial steps required to enable further evaluation of this newly identified pertinent medical risk.

Feasibility and Acceptance of a Teletrauma Surgery Consult Service to Rural and Community Hospitals: A Pilot Study.

BACKGROUND: Many trauma patients currently transferred from rural and community hospitals (RCH) to Level I trauma centers (LITC) for trauma surgery evaluation may instead be appropriate for immediate discharge or admission to the local facility after evaluation by a trauma and acute care surgery (TACS) surgeon. Unnecessary use of resources occurs with current practice. We aimed to demonstrate the feasibility and acceptance of a teletrauma surgery consultation service between LITC and RCH. STUDY DESIGN: LITC TACS surgeons provided telehealth consults on trauma patients from 3 local RCHs. After consultation, appropriate patients were transferred to LITC; selected patients remained at or were discharged from RCH. Participating TACS surgeons and RCH physicians were surveyed. RESULTS: A total of 28 patients met inclusion criteria during the 5-month pilot phase, with 7 excluded due to workflow issues. The mean ± SD age was 63 ± 17 years. Of 21 patients, 7 had intracranial hemorrhage; 12 had rib fractures. The mean ± SD Injury Severity Score was 8.1 ± 4.0). A total of 6 patients were discharged from RCH, 4 admitted to RCH hospitalist service, 2 transferred to a LITC emergency room, and 9 transferred to LITC as direct admission. There was one 30-day readmission and no missed injuries or complications, or deaths. RCH providers were highly satisfied with the teletrauma surgery consultation service, TACS surgeons, and equipment used. Mental demand and effort of consulting TACS surgeons decreased significantly as the consult number increased. CONCLUSIONS: Teletrauma surgery consultation involving 3 RCH within our system is feasible and acceptable. A total of 10 transfers and 19 emergency department visits were avoided. There was favorable acceptance by RCH providers and TACS surgeons.

American Helicopter Emergency Medical Service Pilots Report to Work Despite High Rates of Sleepiness.

OBJECTIVE: Previous studies on helicopter emergency medical service (HEMS) pilots found a positive correlation among fatigue, nodding off in flight, and accidents. We sought to quantify the amount of sleepiness in HEMS pilots using the Epworth Sleepiness Scale (ESS). METHODS: An anonymous survey was sent via the National EMS Pilots Association emergency medical services listserv including demographics, the ESS, and subjective effects of fatigue on flying. Statistical analyses were performed using the t-test and analysis of variance. RESULTS: Thirty-one surveys were returned. Twenty-one (65%) reported an ESS > 10, indicating excessive daytime sleepiness. Twelve (39%) reported nodding off in flight; 20 (65%) indicated that they should have refused to fly, but only 14 (45%) actually did. En route was the most likely phase of flight to be affected by fatigue (23 [74%]), whereas takeoff (2 [7%]) and landing (2 [7%]) were the least likely to be affected. CONCLUSION: Many HEMS pilots in this small study reported excessive daytime sleepiness. Most respondents indicated that they should have turned down a flight because of fatigue. More research is necessary to quantify the burden of fatigue among HEMS pilots.

Search for Venous Endothelial Biomarkers Heralding Venous Thromboembolism in Space: A Qualitative Systematic Review of Terrestrial Studies.

Background: The recent discovery of a venous thrombosis in the internal jugular vein of an astronaut has highlighted the need to predict the risk of venous thromboembolism in otherwise healthy individuals (VTE) in space. Virchow's triad defines the three classic risk factors for VTE: blood stasis, hypercoagulability, and endothelial disruption/dysfunction. Among these risk factors, venous endothelial disruption/dysfunction remains incompletely understood, making it difficult to accurately predict risk, set up relevant prophylactic measures and initiate timely treatment of VTE, especially in an extreme environment. Methods: A qualitative systematic review focused on endothelial disruption/dysfunction was conducted following the guidelines produced by the Space Biomedicine Systematic Review Group, which are based on Cochrane review guidelines. We aimed to assess the venous endothelial biochemical and imaging markers that may predict increased risk of VTE during spaceflight by surveying the existing knowledge base surrounding these markers in analogous populations to astronauts on the ground. Results: Limited imaging markers related to endothelial dysfunction that were outside the bounds of routine clinical practice were identified. While multiple potential biomarkers were identified that may provide insight into the etiology of endothelial dysfunction and its link to future VTE, insufficient prospective evidence is available to formally recommend screening potential astronauts or healthy patients with any currently available novel biomarker. Conclusion: Our review highlights a critical knowledge gap regarding the role biomarkers of venous endothelial disruption have in predicting and identifying VTE. Future population-based prospective studies are required to link potential risk factors and biomarkers for venous endothelial dysfunction to occurrence of VTE.

Impact of Time Delay on Simulated Operative Video Telementoring: A Pilot Study.

INTRODUCTION: As NASA and private spaceflight companies push forward with plans for missions to cis-lunar and interplanetary space, the risk of surgical emergency increases. At latencies above 500 ms, telesurgery is not likely to be successful, so near-real-time telementoring is a more viable option. We examined the effect of a 700-ms time delay on the performance of first year surgical residents on a simulated task requiring significant feedback from a mentor in a pilot study.METHODS: A simulated surgical task requiring precision and accuracy with built-in error detection was used. Each resident underwent two trials, one with a mentor in the same room and one with the mentor using a teleconference with time delay. Outcomes measured included time to complete task, game pieces successfully removed, number of errors, and scores on the NASA Task Load Index by both mentor and operator. Data were analyzed using paired t-tests.RESULTS: The time delay group removed significantly fewer pieces successfully than the real time group (3.0 vs. 1.6, P = 0.02). There was no difference in the NASA Task Load Index (TLX) scores for the operators between the two groups, but the mentor reported significantly higher scores on Mental Demand (5.6 vs. 12.0, P = 0.04) and Effort (6.2 vs. 11.8, P = 0.05) during the time-delayed trials.DISCUSSION: A 750-ms time delay significantly degraded performance on the task. Though operator TLX scores were not affected, mentor TLX scores indicated significantly increased mental load. Telementoring is viable, but more onerous than in-person mentoring.Kamine TH, Smith BW, Fernandez GL. Impact of time delay on simulated operative video telementoring: a pilot study. Aerosp Med Hum Perform. 2022; 93(2):123-127.

Use of Learning Teams to Improve the Educational Environment of General Surgery Residency.

OBJECTIVE: Recent surgical education literature has focused on means of improving structured educational experience in residency, particularly in the context of limited working hours. In addition, prior studies have illustrated a void in training regarding leadership. Learning teams have been adopted in several medical schools with an aim to improve the educational experience. We instituted resident learning teams with a goal of improving resident education. DESIGN: In the 2015 to 2016 academic year, we implemented a team-based learning (TBL) system of 5 teams each led by 1 to 2 chief residents and containing an approximately equal number of residents from postgraduate year (PGY)1-4. The learning teams competed for points based on weekly quizzes, preparation of materials for resident teaching, and American Board of Surgery In-Training Exam (ABSITE) scores. After a full year of TBL, residents were surveyed on their view of the learning teams with respect to the educational experience in the residency with a series of Likert-type questions. Median ABSITE scores of categorical interns were compared between the 3 years after the implementation of the learning teams and the 4 years prior with a Mann-Whitney U test. SETTING: Beth Israel Deaconess Medical Center, Boston, MA; Tertiary Care Center. PARTICIPANTS: All residents from 2011 to 2018. RESULTS: After TBL implementation, median ABSITE percentile scores of PGY2-5 residents increased (35-44, p = 0.04). PGY1 scores were not significantly changed. After TBL implementation, a majority of residents agreed or strongly agreed that they studied more consistently, felt more prepared for the ABSITE, were more prepared for resident school, learned more in resident school, and that the learning teams improved the educational experience of the residency. CONCLUSIONS: Learning teams subjectively improved the educational experience in our residency and engaged residents in studying and participating. In addition, PGY2-5 ABSITE scores were significantly improved. Learning teams are a program that can be easily adopted by surgical residencies elsewhere.

Abdominal insufflation for laparoscopy increases intracranial and intrathoracic pressure in human subjects.

BACKGROUND: Laparoscopy has emerged as an alternative to laparotomy in select trauma patients. In animal models, increasing abdominal pressure is associated with an increase in intrathoracic and intracranial pressures. We conducted a prospective trial of human subjects who underwent laparoscopic-assisted ventriculoperitoneal shunt placement (lap VPS) with intraoperative measurement of intrathoracic, intracranial and cerebral perfusion pressures. METHODS: Ten patients undergoing lap VPS were recruited. Abdominal insufflation was performed using CO2 to 0, 8, 10, 12 and 15 mmHg. ICP was measured through the ventricular catheter simultaneously with insufflation and with desufflation using a manometer. Peak inspiratory pressures (PIP) were measured through the endotracheal tube. Blood pressure was measured using a noninvasive blood pressure cuff. End-tidal CO2 (ETCO2) was measured for each set of abdominal pressure level. Pressure measurements from all points of insufflation were compared using a two-way ANOVA with a post hoc Bonferroni test. Mean changes in pressures were compared using t test. RESULTS: ICP and PIP increased significantly with increasing abdominal pressure (both p < 0.01), whereas cerebral perfusion pressure (CPP) and mean arterial pressure did not significantly change with increasing abdominal pressure over the range tested. Higher abdominal pressure values were associated with decreased ETCO2 values. CONCLUSION: Increased ICP and PIP appear to be a direct result of increasing abdominal pressure, since ETCO2 did not increase. Though CPP did not change over the range tested, the ICP in some patients with 15 mmHg abdominal insufflation reached values as high as 32 cmH2O, which is considered above tolerance, regardless of the CPP. Laparoscopy should be used cautiously, in patients who present with baseline elevated ICP or head trauma as abdominal insufflation affects intracranial pressure.

Decrease in junior resident case volume after 2011 ACGME work hours.

OBJECTIVE: To determine how the new 2011 Accreditation Council for Graduate Medical Education work hours affected case volume across postgraduate year (PGY) levels of surgical trainees. DESIGN: Retrospective review of Accreditation Council for Graduate Medical Education case logs of surgical residents at Beth Israel Deaconess Medical Center from 2006 to 2013. SETTING: Tertiary care center. PARTICIPANTS: All categorical surgical residents from 2006 to 2013. RESULTS: PGY-1 cases decreased from 139 (122.25-172.5) to 111.5 (102.25-117.5) (p = 0.003). PGY-2 case volume decreased as well from 162 (151.5-192) to 126 (95.5-173) (p = 0.011). Only 45% of PGY-2 residents performed more than 250 major cases after the work hours changed compared with 82% of residents before 2011. PGY-3 cases increased from 263 (215-309) to 309 (282-340) (p = 0.0038). Cases performed by PGY-4 and PGY-5 residents were not statistically different. Total cases performed by graduating chiefs, however, has increased from 987 (848.5-1050) to 1090 (1033-1145) (p = 0.0006). CONCLUSIONS: Intern and PGY-2 case volume has declined at our institution as new work-hour regulations took effect in 2011. However, PGY-3 case volume increased significantly, and graduating chiefs are graduating with more cases. The work hours do not appear to have had the intended result of improving intern educational experience from a standpoint of case volume. Significant programmatic changes will likely be required to achieve the 250-case minimum by the end of PGY-2 year, as per 2014 American Board of Surgery requirements.

Effect of abdominal insufflation for laparoscopy on intracranial pressure.

IMPORTANCE: Increased abdominal pressure may have a negative effect on intracranial pressure (ICP). Human data on the effects of laparoscopy on ICP are lacking. We retrospectively reviewed laparoscopic operations for ventriculoperitoneal shunt placement to determine the effect of insufflation on ICP. OBSERVATIONS: Nine patients underwent insufflation with carbon dioxide (CO(2)) at pressures ranging from 8 to 15 mm Hg and ICP measured through a ventricular catheter. We used a paired t test to compare ICP with insufflation and desufflation. Linear regression correlated insufflation pressure with ICP. The mean ICP increase with 15-mm Hg insufflation is 7.2 (95% CI, 5.4-9.1 [P < .001]) cm H(2)O. The increase in ICP correlated with increasing insufflation pressure (P = .04). Maximum ICP recorded was 25 cm H(2)O. CONCLUSIONS AND RELEVANCE: Intracranial pressure significantly increases with abdominal insufflation and correlates with laparoscopic insufflation pressure. The maximum ICP measured was a potentially dangerous 25 cm H(2)O. Laparoscopy should be used cautiously in patients with a baseline elevated ICP or head trauma.

Effects of the new Accreditation Council for Graduate Medical Education work hour rules on surgical interns: a prospective study in a community teaching hospital.

BACKGROUND: On July 1, 2011, the Accreditation Council for Graduate Medical Education (ACGME) eliminated 30-hour call in an attempt to improve resident wakefulness. We surveyed interns on the Newton Wellesley Hospital (NWH) surgery service before and after the transition from Q4 overnight call to a night float schedule. METHODS: For 15 weeks, interns completed weekly surveys including the Epworth Sleepiness Scale (ESS). The service changed to a night float schedule after 3 weeks (ie, first to 3-4 and then to 6 nights in a row). RESULTS: The average ESS score rose from 9.8 ± 5.2 to 14.9 ± 3.1 and 14.4 ± 4.5 (P = .042) on the 3/4 and 6/1 schedules, respectively. Interns were more likely to be abnormally tired on either night float schedule (relative risk = 2.86; 95% confidence interval, 1.17-6.97, P = .029). CONCLUSIONS: The new ACGME work hours increased the ESS scores among interns at NWH and caused interns to be more tired than interns on the Q4 schedule. This is likely caused by the multiple nights of poor sleep without a post-call day to make up sleep.

Visual display angles of conventional and a remotely piloted aircraft.

INTRODUCTION: Instrument display separation and proximity are important human factor elements used in the design and grouping of aircraft instrument displays. To assess display proximity in practical operations, the viewing visual angles of various displays in several conventional aircraft and in a remotely piloted vehicle were assessed. METHODS: The horizontal and vertical instrument display visual angles from the pilot's eye position were measured in 12 different types of conventional aircraft, and in the ground control station (GCS) of a remotely piloted aircraft (RPA). A total of 18 categories of instrument display were measured and compared. RESULTS: In conventional aircraft almost all of the vertical and horizontal visual display angles lay within a "cone of easy eye movement" (CEEM). Mission-critical instruments particular to specific aircraft types sometimes displaced less important instruments outside the CEEM. For the RPA, all horizontal visual angles lay within the CEEM, but most vertical visual angles lay outside this cone. DISCUSSION: Most instrument displays in conventional aircraft were consistent with display proximity principles, but several RPA displays lay outside the CEEM in the vertical plane. Awareness of this fact by RPA operators may be helpful in minimizing information access cost, and in optimizing RPA operations.