Measuring atmospheric turbulence along folded paths using a laser-illuminated differential image motion monitor.

A laser-illuminated differential image motion monitor (DIMM) is presented that is able to measure the atmospheric coherence length r 0 along horizontal ground paths. This is accomplished by implementing a mono-static setup in which the transmitter and receiver are co-located and transmit to a retroreflective target. The impact of propagating along a folded path through the same volume of turbulent atmosphere is investigated in detail and the overall impact to angle-of-arrival measurements described. In addition, an outdoor test campaign was conducted to validate the findings by testing two commercial scintillometers and the laser DIMM side by side in both bi-static and mono-static configurations. Both analytical and experimental results show that under certain conditions, folded-path propagation can be treated identically to traditional single-path propagation.

Numerical simulation of a large area scintillometer and laser differential image motion monitor.

Measurements of atmospheric turbulence along a path can be quantified by scintillometers and differential image motion monitors (DIMMs). The two instruments often measure different levels of turbulence, sometimes varying by nearly an order of magnitude. A high-fidelity numerical simulation was leveraged to assess the measurement performance of both a scintillometer and a DIMM system. When a non-ideal detector is combined with range-dependent turbulence, significant differences between the scintillometer and DIMM are observed. The difference in measurements obtained with the numerically simulated scintillometer and DIMM was consistent with those observed in side-by-side measurements with the instruments.

Relative Position of the Third Characteristic Peak of the Intracranial Pressure Pulse Waveform Morphology Differentiates Normal-Pressure Hydrocephalus Shunt Responders and Nonresponders.

INTRODUCTION: The diversion of cerebrospinal fluid (CSF) remains the principal treatment option for patients with normal-pressure hydrocephalus (NPH). External lumbar drain (ELD) and overnight intracranial pressure (ICP) monitoring are popular prognostic tests for differentiating which patients will benefit from shunting. Using the morphological clustering and analysis of continuous intracranial pulse (MOCAIP) algorithm to extract morphological metrics from the overnight ICP signal, we hypothesize that changes in the third peak of the ICP pulse pressure waveform can be used to differentiate ELD responders and nonresponders. MATERIALS AND METHODS: Our study involved 66 patients (72.2 ± 9.8 years) undergoing evaluation for possible NPH, which included overnight ICP monitoring and ELD. ELD outcome was based on clinical notes and divided into nonresponders and responders. MOCAIP was used to extract mean ICP, ICP wave amplitude (waveAmp), and a metric derived to study P3 elevation (P3ratio). RESULTS: Of the 66 patients, 7 were classified as nonresponders and 25 as significant responders. The mean ICP and waveAmp did not vary significantly (p = 0.19 and p = 0.41) between the outcome groups; however, the P3ratio did show a significant difference (p = 0.04). CONCLUSION: Initial results suggest that the P3ratio might be used as a prognostic indicator for ELD outcome.

Model of Current Practice Regarding Prescriptions of Controlled Substances and the Perceived Benefits of E-Prescribing in an Academic Medical Center.

To review current practices regarding prescribing controlled substances at an academic medical center and describe possible advantages of electronic prescribing of controlled substances (EPCS). A 10-question multiple choice survey was sent electronically to all house staff at an academic medical center. Aggregated data was analyzed for trends. 193 surveys (18.8 %) were completed. Of all respondents, 46.6 % were not able to write their own prescriptions. 70.0 % have used another provider's prescription pad to write prescriptions. 53.4 % have had prescriptions rejected or not filled by a pharmacy for being written incorrectly. 59.6 % kept a patient as an inpatient for a longer period of time due to the inability to obtain a prescription, costing an estimated $3.28 million per year. 58.0 % needed to have a patient return to the hospital to pick up prescriptions for an estimated 1583 return trips to the hospital yearly. 35.1 % had a patient return to the emergency department due to uncontrolled pain, estimated at $139,000 in yearly emergency department patient charges. The authors' survey highlights some of the financial, legal, efficiency, and satisfaction disadvantages due to the inability to use EPCS. Implementing EPCS and making it ubiquitous may limit some inefficiencies in academic hospital systems.

Automated extraction of decision rules for predicting lumbar drain outcome by analyzing overnight intracranial pressure.

BACKGROUND: Extended lumbar drain (ELD) has become a popular pre-shunt workup test to help diagnose normal pressure hydrocephalus (NPH). Unfortunately, this procedure requires a substantial time investment for both the family and hospital. In this study, we investigate how accurate the prediction of ELD outcome can be achieved by using simple decision rules automatically derived from pulse morphological metrics of overnight ICP recordings. Our ultimate goal is to test the hypothesis that overnight ICP monitoring, empowered by subsequent signal analysis, could be an alternative to ELD. METHODS: The present study involved 54 patients with both ELD and overnight ICP recordings; the ICP morphological analysis was performed using the MOCAIP algorithm. Furthermore, the distribution of individual metric from the overnight recording was characterized using five aggregation functions (features). Then an algorithm was developed to automatically discover the most accurate "if-then" decision rule for each of the five feature functions. In addition, the best combination of two decision rules, either using "AND" or "OR" operator, was obtained. FINDINGS: Rules based on five individual feature functions achieved an accuracy of 70.4%, 72.2%, 74.1%, 72.2%, and 79.6% respectively. However, "OR" combination of two features improved accuracy to 88.9%. CONCLUSION: We showed an algorithm to discover decision rules that can potentially predict ELD outcome.

Quantification of pulsatile cerebrospinal fluid flow within the prepontine cistern.

BACKGROUND: Phase-contrast MRI (PC-MRI) has previously been used for the quantification of CSF and blood flow throughout the body. We propose a new method of semi-automated segmentation for the prepontine cistern based on anatomical and pulsatility information. METHODS: Scans were conducted on 48 patients (69.83 ± 14.28 years) ranging in age from 32 to 88 years along with an additional 11 controls (51.91 ± 21.13 years) ranging in age from 22 to 72 years. The segmentation algorithm developed consists of four stages: anatomical, flow quantification for the aqueduct and prepontine cistern, and blood vessel detection. RESULTS: Complete results are presented in Table 1, the 37 preoperative patients and controls had a prepontine cistern stroke volume of 464.32 ± 202.30 and 447.38 ± 75.49 respectively. CONCLUSION: Reliable quantification of volumetric CSF flow in complex cisternal spaces is possible using a methodology combining known anatomical features with the pulsatile nature of CSF flow.

Characteristics of the National Applicant Pool for Clinical Informatics Fellowships (2018-2020).

In a prior survey, we found that applicants for 2017 ACGME-accredited clinical informatics fellowship positions were only 24% female and only 3% were members of underrepresented minorities (URM, consisting of American Indian or Alaska Native, Black or African American, Hispanic, Latino, or Spanish Origin, or Native Hawaiian or Other Pacific Islander). Since 2018, applications for clinical informatics fellowships have been accepted through the AAMC's Electronic Residency Application Service (ERAS). We analyzed national data from ERAS on applicants to clinical informatics fellowship programs for 2018 to 2020 positions. We also obtained applicants' subsequent success in starting clinical informatics fellowship training from the AAMC's GME Track survey. Over these 3 years, we found that the fellowship applicant pool grew from 63 to 74 (17%) and the number of positions offered grew from 34 to 41 (17%). The proportion of women applicants grew to 34% by 2020 and the proportion of underrepresented minorities grew to 12% by 2020. By comparison, medical students 7 years earlier (2013) were 47% female (P=.01) and 16% URM (P>.20), and applicants to many other subspecialties were similar. Applicants' sex and URM membership were not associated with success in starting fellowship training. We conclude that the underrepresentation of women and URM members in clinical informatics fellowships has improved but not resolved. Urgent efforts are needed to increase the both the numbers and the diversity of clinical informatics applicants by promoting the field among medical students and residents, particularly among women and URM members.

Distinct components of alert fatigue in physicians' responses to a noninterruptive clinical decision support alert.

OBJECTIVE: Clinical decision support (CDS) alerts may improve health care quality but "alert fatigue" can reduce provider responsiveness. We analyzed how the introduction of competing alerts affected provider adherence to a single depression screening alert. MATERIALS AND METHODS: We analyzed the audit data from all occurrences of a CDS alert at a large academic health system. For patients who screen positive for depression during ambulatory visits, a noninterruptive alert was presented, offering a number of relevant documentation actions. Alert adherence was defined as the selection of any option offered within the alert. We assessed the effect of competing clinical guidance alerts presented during the same encounter and the total of all CDS alerts that the same provider had seen in the prior 90 days, on the probability of depression screen alert adherence, adjusting for physician and patient characteristics. RESULTS: The depression alert fired during 55 649 office visits involving 418 physicians and 40 474 patients over 41 months. After adjustment, physicians who had seen the most alerts in the prior 90 days were much less likely to respond (adjusted OR highest-lowest quartile, 0.38; 95% CI 0.35-0.42; P < .001). Competing alerts in the same visit further reduced the likelihood of adherence only among physicians in the middle two quartiles of alert exposure in the prior 90 days. CONCLUSIONS: Adherence to a noninterruptive depression alert was strongly associated with the provider's cumulative alert exposure over the past quarter. Health systems should monitor providers' recent alert exposure as a measure of alert fatigue.

Optimizing Inpatient Blood Utilization Using Real-Time Clinical Decision Support.

BACKGROUND: Red blood cell (RBC) transfusion is a common medical procedure. While it offers clinical benefits for many, hemodynamically stable patients are often subjected to unwarranted transfusions, with the potential to lead to adverse consequences. We created a real-time clinical decision support (CDS) tool in the electronic health record system to address this problem and optimize transfusion practice as part of an institutional multidisciplinary, team-based patient blood management program. METHODS: The real-time CDS tool incorporated the transfusion guidelines published by the AABB. The tool was deployed as a dynamic order set within the computerized provider order entry interface. Prior to implementation, extensive education and outreach to increase provider engagement were provided. The CDS tool was launched in September 2015. RESULTS: The percentage of guideline-indicated RBC transfusions increased from a baseline of 43.6 to 54.2% while the percentage of multiunit (≥ 2 units) RBC transfusions decreased from 31.3 to 22.7% between September 2014 and July 2019. The estimated minimum cost saving over the entire study period was $36,519.36. CONCLUSION: Our intervention increased guideline-indicated transfusions by 10.6% and reduced multiunit transfusions by 8.6%. The adoption of a dynamic order set for the CDS tool, as opposed to an interruptive alert that displays static alert messages, allowed for more customized and tighter control of RBC orders, leading to a sustained improvement in our transfusion practice.

Falling as a strategy to decrease knee loading during landings: Implications for ACL injury prevention.

Anterior cruciate ligament (ACL) injuries often occur when individuals land primarily on a single leg. Falling has been proposed as a potential strategy to decrease knee loading during landings. The purpose of this study was to compare impact forces, knee angles, and knee moments during natural landings, soft landings, and landings followed by falling after forward and vertical jumps, each under single or double-leg conditions. Sixteen male and sixteen female participants (age: 22.0 ± 2.9 years) completed each landing condition while kinematics and ground reaction forces were collected. In the natural landing condition, participants landed as they would in a sport setting. In the soft landing condition, participants landed as softly as possible with increased knee and hip flexion. In the falling condition, participants landed softly and then fell forward or backward onto a mat after forward and vertical jumps, respectively. The falling condition demonstrated the greatest initial and peak knee flexion angles, the least peak vertical ground reaction forces, and the least peak knee extension and adduction moments compared to the natural landing and soft landing conditions. The soft landing condition resulted in similar changes in landing mechanics compared to the natural landing, but the effect was limited for single-leg landings compared to double-leg landings. When the sports environment allows, falling appears to be a potential strategy to decrease knee loading when individuals must land on a single leg with sub-optimal body postures. Future studies are needed to develop progressive training of effective and safe falling techniques.

How Patients Use a Patient Portal: An Institutional Case Study of Demographics and Usage Patterns.

BACKGROUND: Given the widespread electronic health record adoption, there is increasing interest to leverage patient portals to improve care. OBJECTIVE: To determine characteristics of patient portal users and the activities they accessed in the patient portal. METHODS: We performed a retrospective analysis of patient portal usage at University of California, Los Angeles, Health from July 2014 to May 2015. A total dataset of 505,503 patients was compiled with 396,303 patients who did not register for the patient portal and 109,200 patients who registered for a patient portal account. We compared patients who did not register for the online portal to the top 75th percentile of users based on number of logins, which was done to exclude those who only logged in to register. Finally, to avoid doing statistical analysis on too large of a sample and overpower the analysis, we performed statistical tests on a random sample of 300 patients in each of the two groups. RESULTS: Patient portal users tended to be older (49.45 vs. 46.22 years in the entire sample, p = 0.008 in the random sample) and more likely female (62.59 vs. 54.91% in the entire sample, p = 0.035 in the random sample). Nonusers had more monthly emergency room (ER) visits on average (0.047 vs. 0.014, p < 0.001). The most frequently accessed activity on the portal was viewing laboratory results (79.7% of users looked at laboratory results). CONCLUSION: There are differences between patient portal users and nonusers, and further understanding of these differences can serve as foundation for further investigation and possible interventions to drive patient engagement and health outcomes.

Opposing CSF hydrodynamic trends found in the cerebral aqueduct and prepontine cistern following shunt treatment in patients with normal pressure hydrocephalus.

BACKGROUND: This study investigated cerebrospinal fluid (CSF) hydrodynamics using cine phase-contrast MRI in the cerebral aqueduct and the prepontine cistern between three distinct groups: pre-shunt normal pressure hydrocephalus (NPH) patients, post-shunt NPH patients, and controls. We hypothesized that the hyperdynamic flow of CSF through the cerebral aqueduct seen in NPH patients was due to a reduction in cisternal CSF volume buffering. Both hydrodynamic (velocity, flow, stroke volume) and peak flow latency (PFL) parameters were investigated. METHODS: Scans were conducted on 30 pre-treatment patients ranging in age from 58 to 88 years along with an additional 12 controls. Twelve patients also received scans following either ventriculoatrial (VA) or ventriculoperitoneal (VP) shunt treatment (9 VP, 3 VA), ranging in age from 74 to 89 years with a mean follow up time of 6 months. RESULTS: Significant differences in area, velocity, flow, and stroke volume for the cerebral aqueduct were found between the pre-treatment NPH group and the healthy controls. Shunting caused a significant decrease in both caudal and cranial mean flow and stroke volume in the cerebral aqueduct. No significant changes were found in the prepontine cistern between the pre-treatment group and healthy controls. For the PFL, no significant differences were seen in the cerebral aqueduct between any of the three groups; however, the prepontine cistern PFL was significantly decreased in the pre-treatment NPH group when compared to the control group. CONCLUSIONS: Although several studies have quantified the changes in aqueductal flow between hydrocephalic groups and controls, few studies have investigated prepontine cistern flow. Our study was the first to investigate both regions in the same patients for NPH pre- and post- treatment. Following shunt treatment, the aqueductal CSF metrics decreased toward control values, while the prepontine cistern metrics trended up (not significantly) from the normal values established in this study. The opposing trend of the two locations suggests a redistribution of CSF pulsatility in NPH patients. Furthermore, the significantly decreased latency of the prepontine cisternal CSF flow suggests additional evidence for CSF pulsatility dysfunction.

An algorithm for extracting intracranial pressure latency relative to electrocardiogram R wave.

Intracranial pressure (ICP) latency is defined as the time interval between the peak of the QRS complex of the electrocardiogram (ECG) and the corresponding onset of intracranial pressure (ICP) pulse. Due to its inherent relationship with arterial pulse wave velocity, ICP latency may allow continuous monitoring of pathophysiological changes in the cerebrovasculature. The objective of the present work was to develop and validate a computerized algorithm for extracting ICP latency in a beat-by-beat fashion. The proposed ICP latency extraction algorithm exploits the mature technique of ECG QRS detection and includes a new adaptive peak detection methodology. The results were validated by comparing the performance of two human observers versus the algorithm in terms of locating the onset points of ICP pulses for 59 recordings extracted from 25 adult patients. The average ICP latency was 72.6+/-19.5 ms (range 40.0-159.8). The ICP pulse detection algorithm demonstrated a baseline sensitivity of 0.97 and a positive predictivity of 0.88. No difference was found in the mean location errors from comparing the results obtained by the two observers and those from comparing the results from the algorithm to those from the two observers. Further investigation is needed to demonstrate the role of ICP latency in characterizing dynamic cerebral vascular pathophysiological changes in clinical states such as subarachnoid hemorrhage and traumatic brain injury.

Characteristics of the National Applicant Pool for Clinical Informatics Fellowships (2016-2017).

We conducted a national study to assess the numbers and diversity of applicants for 2016 and 2017 clinical informatics fellowship positions. In each year, we collected data on the number of applications that programs received from candidates who were ultimately successful vs. unsuccessful. In 2017, we also conducted an anonymous applicant survey. Successful candidates applied to an average of 4.2 and 5.5 programs for 2016 and 2017, respectively. In the survey, unsuccessful candidates reported applying to fewer programs. Assuming unsuccessful candidates submitted between 2-5 applications each, the total applicant pool numbered 42-69 for 2016 (competing for 24 positions) and 52-85 for 2017 (competing for 30 positions). Among survey respondents (n=33), 24% were female, 1 was black and none were Hispanic. We conclude that greater efforts are needed to enhance interest in clinical informatics among medical students and residents, particularly among women and members of underrepresented minority groups.

Visual and cognitive predictors of performance on brake reaction test: Salisbury eye evaluation driving study.

OBJECTIVES: Concern for driving safety has prompted research into understanding factors related to performance. Brake reaction speed (BRS), the speed with which persons react to a sudden change in driving conditions, is a measure of performance. Our aim is to determine the visual, cognitive, and physical factors predicting BRS in a population sample of 1425 older drivers. METHODS: The Maryland Department of Motor Vehicles roster of persons aged 67-87 and residing in Salisbury, MD, was used for recruitment of the study population. Procedures included the following: habitual, binocular visual acuity using ETDRS charts, contrast sensitivity using a Pelli-Robson chart, visual fields assessed with a 81-point screening Humphrey field at a single intensity threshold, and a questionnaire to ascertain medical conditions. Cognitive status was assessed using a standard battery of tests for attention, memory, visuo-spatial, and scanning. BRS was assessed using a computer-driven device that measured separately the initial reaction speed (IRS) (from light change to red until removing foot from accelerator) and physical response speed (PRS) (removing foot from accelerator to full brake depression). Five trial times were averaged, and time was converted to speed. RESULTS: The median brake reaction time varied from 384 to 5688 milliseconds. Age, gender, and cognition predicted total BRS, a non-informative result as there are two distinct parts to the task. Once separated, decrease in IRS was associated with low scores on cognitive factors and missing points on the visual field. A decrease in PRS was associated with having three or more physical complaints related to legs and feet, and poorer vision search. Vision was not related to PRS. CONCLUSION: We have demonstrated the importance of segregating the speeds for the two tasks involved in brake reaction. Only the IRS depends on vision. Persons in good physical condition may perform poorly on brake reaction tests if their vision or cognition is compromised.

The UCLA Health Resident Informaticist Program - A Novel Clinical Informatics Training Program.

Few opportunities exist for physician trainees to gain exposure to, and training in, the field of clinical informatics, an Accreditation Council for Graduate Medical Education-accredited, recently board-certified specialty. Currently, 21 approved programs exist nationwide for the formal training of fellows interested in pursuing careers in this discipline. Residents and fellows training in medical and surgical fields, however, have few avenues available to gain experience in clinical informatics. An early introduction to clinical informatics brings an opportunity to generate interest for future career trajectories. At University of California Los Angeles (UCLA) Health, we have developed a novel, successful, and sustainable program, the Resident Informaticist Program, with the goals of exposing physician trainees to the field of clinical informatics and its academic nature and providing opportunities to expand the clinical informatics workforce. Herein, we provide an overview of the development, implementation, and current state of the UCLA Health Resident Informaticist Program, with a blueprint for development of similar programs.

Straight talk: new approaches in healthcare. Integrated revenue cycle operations--leveraging technology and human capital.

This is the third installment in a series of group discussions by top executives on key issues in healthcare today. Straight Talk is presented by Modern Healthcare and PricewaterhouseCoopers. This session tackles the subject of revenue-cycle management. Moderated by Charles S. Lauer, the discussion was held on May 7, 2002 at Modern Healthcare's Chicago headquarters.

Straight talk new approaches in healthcare. Performance management: assuring your financial and performance goals are met.

Performance management is a topic thrown around a lot in executive suites, but its key tenets are sometimes misunderstood. To be successful, performance management involves setting strategy at the board and executive levels and making day-to-day decisions at the line-manager level. But the process won't work unless those line managers have clearly defined goals to achieve as well as relevant reliable and timely information to assist them in monitoring their performance and making operational decisions to improve outcomes. Modern Healthcare and Pricewaterhouse Coopers present Straight Talk in the tenth installment of Straight Talk we discuss the steps necessary to build a successful performance-management program. The session was held at Modern Healthcare's Chicago head-quarters on January 7, 2003. Charles S. Lauer, publisher of Modern Healthcare, was the moderator.

Older drivers and rapid deceleration events: Salisbury Eye Evaluation Driving Study.

Drivers who rapidly change speed while driving may be more at risk for a crash. We sought to determine the relationship of demographic, vision, and cognitive variables with episodes of rapid decelerations during five days of normal driving in a cohort of older drivers. In the Salisbury Eye Evaluation Driving Study, 1425 older drivers aged 67-87 were recruited from the Maryland Motor Vehicle Administration's rolls for licensees in Salisbury, Maryland. Participants had several measures of vision tested: visual acuity, contrast sensitivity, visual fields, and the attentional visual field. Participants were also tested for various domains of cognitive function including executive function, attention, psychomotor speed, and visual search. A custom created driving monitoring system (DMS) was used to capture rapid deceleration events (RDEs), defined as at least 350 milli-g deceleration, during a five day period of monitoring. The rate of RDE per mile driven was modeled using a negative binomial regression model with an offset of the logarithm of the number of miles driven. We found that 30% of older drivers had one or more RDE during a five day period, and of those, about 1/3 had four or more. The rate of RDE per mile driven was highest for those drivers driving<59 miles during the 5-day period of monitoring. However, older drivers with RDE's were more likely to have better scores in cognitive tests of psychomotor speed and visual search, and have faster brake reaction time. Further, greater average speed and maximum speed per driving segment was protective against RDE events. In conclusion, contrary to our hypothesis, older drivers who perform rapid decelerations tend to be more "fit", with better measures of vision and cognition compared to those who do not have events of rapid deceleration.