- Emergency Medicine
Clinical Associate Professor, Emergency Medicine
Clinical Associate Professor, Pediatrics
Medical Director, Call Back Nurse Program, Stanford Healthcare Emergency Department (2011 - 2016)
Associate Medical Director, APP Fellowship, Stanford School of Medicine Emergency Medicine (2016 - 2018)
Associate Medical Director (Informatics and Data Analytics), Stanford School of Medicine Emergency Medicine (2021 - Present)
Assistant Medical Director (Informatics and Data Analytics), Stanford School of Medicine Emergency Medicine (2016 - 2021)
Assistant Medical Director, Stanford School of Medicine Emergency Medicine (2014 - 2016)
Medical Informatics Director, Stanford Healthcare (2011 - Present)
Board Certification: American Board of Emergency Medicine, Emergency Medicine (2004)
Medical Education: Hahnemann University Medical College (2000) PA
Board Certification: American Board of Preventive Medicine, Clinical Informatics (2015)
Residency: Johns Hopkins University School of Medicine (2003) MD
Internship: Johns Hopkins University School of Medicine (2001) MD
Impact of telemedicine on clinical practice patterns for patients with chest pain in the emergency department.
International journal of medical informatics
2022; 161: 104726
BACKGROUND: The outbreak of the COVID-19 pandemic has led to the rapid adoption of novel telemedicine programs within the emergency department (ED) to minimize provider exposure and conserve personal protective equipment (PPE). In this study, we sought to assess how the adoption of telemedicine in the ED impacted clinical order patterns for patients with chest pain. We hypothesize that clinicians would rely more on imaging and laboratory workup for patients receiving telemedicine due to limitation in physical exams.METHODS: A single-center, retrospective, propensity score matched study was designed for patients presenting with chest pain at an ED. The study period was defined between April 1st, 2020 and September 30th, 2020. The frequency of the most frequent lab, imaging, and medication orders were compared. In addition, poisson regression analysis was performed to compare the overall number of orders between the two groups.RESULTS: 455 patients with chest pain who received telemedicine were matched to 455 similar patients without telemedicine with standardized mean difference<0.1 for all matched covariates. The proportion of frequent lab, imaging, and medication orders were similar between the two groups. However, telemedicine patients received more orders overall (RR, 1.19, 95% CI, 1.11, 1.28, p-value<0.001) as well as more imaging, lab, and nursing orders. The number of medication orders between the two groups remained similar.CONCLUSIONS: Frequent labs, imaging, and medications were ordered in similar proportions between the two cohorts. However, telemedicine patients had more orders placed overall. This study is an important objective assessment of the impact that telemedicine has upon clinical practice patterns and can guide future telemedicine implementation after the COVID-19 pandemic.
View details for DOI 10.1016/j.ijmedinf.2022.104726
View details for PubMedID 35228006
Examination of physician characteristics in opioid prescribing in the emergency department.
The American journal of emergency medicine
2021; 50: 207-210
AIM: We aimed to better understand variation in opioid prescribing practices by investigating physician factors at one academic suburban Emergency Department (ED).METHODS: We retrospectively reviewed the electronic medical records of all patients given opioid prescriptions in the Stanford Health Care ED from 2009 to 2018. We described the variation in opioid prescriptions over time from 2009 to 2018, then dove deeper into a single year (July 1, 2017 to July 1, 2018). We described the number and type of opioid prescriptions at discharge and variation in attending physician opioid prescribing patterns using independent t-tests and a Fischer's exact test.RESULTS: From 2009 to 2018, 657,037 patient visits occurred; 92,612 (14.1%) opioid prescriptions were written. Opioid prescriptions increased from 2009, peaked in 2015, then decreased. Individual providers wrote opioid prescriptions for 1 to 17% of their discharged patients. There was no significant difference in opioid prescribing based on provider gender (p = 0.456), fellow or attending status (p = 0.390), residency completed at Stanford Hospital (p = 0.593), residency completed within California (p = 0.493), or residency completed after 2010 (p = 0.589). Of the 371 providers who wrote opioid prescriptions from 2009 through 2018, 120 wrote prescriptions for patients who had already received at least three opioid prescriptions in the same year from the same department.CONCLUSION: This study could inform policymakers by describing patterns of variation in opioid prescribing over time and between providers. Although we did see significant differences in prescribing patterns from one provider to the next, those were not explained by the factors we examined. Further studies could investigate factors such as provider experience with pain and addiction, bias regarding particular pathologies, and concern around patient satisfaction scores.
View details for DOI 10.1016/j.ajem.2021.07.051
View details for PubMedID 34390904
Using a Real-Time Locating System to Evaluate the Impact of Telemedicine in an Emergency Department During COVID-19: Observational Study.
Journal of medical Internet research
Telemedicine has been deployed by healthcare systems in response to the COVID-19 pandemic to enable healthcare workers to provide remote care for both outpatients and inpatients. Although it is reasonable to suspect telemedicine visits limit unnecessary personal contact and thus decrease the risk of infection transmission, the impact of the use of such technology on clinician workflows in the emergency department is unknown.To use real-time locating systems (RTLS) to evaluate the impact of a new telemedicine platform, which permitted clinicians located outside patient rooms to interact with patients who were under isolation precautions in the emergency department, on in-person interaction between healthcare workers and patients.A pre-post analysis was conducted using a badge-based RTLS platform to collect movement data including entrances and duration of stay within patient rooms of the emergency department for nursing and physician staff. Movement data was captured between March 2nd, 2020, the date of the first patient screened for COVID-19 in the emergency department, and April 20th, 2020. A new telemedicine platform was deployed on March 29th, 2020. Number of entrances and duration of in-person interactions per patient encounter, adjusted for patient length of stay, were obtained for pre- and post-implementation phases and compared with t-tests to determine statistical significance.There were 15,741 RTLS events linked to 2,662 encounters for patients screened for COVID-19. There was no significant change in number of in-person interactions between the pre- and post-implementation phases for both nurses (5.7 vs 7.0 entrances per patient, p=0.07) and physicians (1.3 vs 1.5 entrances per patient, p=0.12). Total duration of in-person interaction did not change (56.4 vs 55.2 minutes per patient, p=0.74) despite significant increases in telemedicine videoconference frequency (0.6 vs 1.3 videoconferences per patient, p<0.01 for change in daily average) and duration (4.3 vs 12.3 minutes per patient, p<0.01 for change in daily average).Telemedicine was rapidly adopted with the intent of minimizing pathogen exposure to healthcare workers during the COVID-19 pandemic, yet RTLS movement data did not reveal significant changes for in-person interactions between staff and patients under investigation for COVID-19 infection. Additional research is needed to better understand how telemedicine technology may be better incorporated into emergency departments to improve workflows for frontline healthcare clinicians.
View details for DOI 10.2196/29240
View details for PubMedID 34236993
Prehospital Identification of Large Vessel Occlusions Using Modified National Institutes of Health Stroke Scale: A Pilot Study.
Frontiers in neurology
2021; 12: 643356
Stroke identification is a key step in acute ischemic stroke management. Our objectives were to prospectively examine the agreement between prehospital and hospital Modified National Institutes of Health Stroke Scale (mNIHSS) assessments as well as assess the prehospital performance characteristics of the mNIHSS for identification of large vessel occlusion strokes. Method: In this prospective cohort study conducted over a 20-month period (11/2016-6/2018), we trained 40 prehospital providers (paramedics) in Emergency Neurological Life Support (ENLS) curriculum and in mNIHSS. English-speaking patients aged 18 and above transported for an acute neurological deficit were included. Using unique identifiers, we linked the prehospital assessment records to the hospital record. We calculated the agreement between prehospital and hospital mNIHSS scores using the Bland-Altman analysis and the sensitivity and specificity of the prehospital mNIHSS. Results: Of the 31 patients, the mean difference (prehospital mNIHSS-hospital mNIHSS) was 2.4, 95% limits of agreement (-5.2 to 10.0); 10 patients (32%) met our a priori imaging definition of large vessel occlusion and the sensitivity of mNIHSS ≥ 8 was 6/10 or 0.60 (95% CI: 0.26-0.88) and the specificity was 13/21 or 0.62 (95% CI: 0.38-0.82), respectively. Conclusions: We were able to train prehospital providers to use the prehospital mNIHSS. Prehospital and hospital mNIHSS had a reasonable level of agreement and and the scale was able to predict large vessel occlusions with moderate sensitivity.
View details for DOI 10.3389/fneur.2021.643356
View details for PubMedID 34054691
Emergency Department Access During COVID-19: Disparities in Utilization by Race/Ethnicity, Insurance, and Income
Western Journal of Emergency Medicine
In March 2020, shelter-in-place orders were enacted to attenuate the spread of coronavirus 2019 (COVID-19). Emergency departments (EDs) experienced unexpected and dramatic decreases in patient volume, raising concerns about exacerbating health disparities.We queried our electronic health record to describe the overall change in visits to a two-ED healthcare system in Northern California from March-June 2020 compared to 2019. We compared weekly absolute numbers and proportional change in visits focusing on race/ethnicity, insurance, household income, and acuity. We calculated the z-score to identify whether there was a statistically significant difference in proportions between 2020 and 2019.Overall ED volume declined 28% during the study period. The nadir of volume was 52% of 2019 levels and occurred five weeks after a shelter-in-place order was enacted. Patient demographics also shifted. By week 4 (April 5), the proportion of Hispanic patients decreased by 3.3 percentage points (pp) (P = 0.0053) compared to a 6.2 pp increase in White patients (P = 0.000005). The proportion of patients with commercial insurance increased by 11.6 pp, while Medicaid visits decreased by 9.5 pp (P < 0.00001) at the initiation of shelter-in-place orders. For patients from neighborhoods <300% federal poverty levels (FPL), visits were -3.8 pp (P = 0.000046) of baseline compared to +2.9 pp (P = 0.0044) for patients from ZIP codes at >400% FPL the week of the shelter-in-place order. Overall, 2020 evidenced a consistently elevated proportion of high-acuity Emergency Severity Index (ESI) level 1 patients compared to 2019. Increased acuity was also demonstrated by an increase in the admission rate, with a 10.8 pp increase from 2019. Although there was an increased proportion of high-acuity patients, the overall census was decreased.Our results demonstrate changing ED utilization patterns circa the shelter-in-place orders. Those from historically vulnerable populations such as Hispanics, those from lower socioeconomic areas, and Medicaid users presented at disproportionately lower rates and numbers than other groups. As the pandemic continues, hospitals should use operations data to monitor utilization patterns by demographic, in addition to clinical indicators. Messaging about availability of emergency care and other services should include vulnerable populations to avoid exacerbating healthcare disparities.
View details for DOI 10.5811/westjem.2021.1.49279
Social Determinants of Hallway Bed Use.
The western journal of emergency medicine
2020; 21 (4): 949–58
INTRODUCTION: Hallway beds in the emergency department (ED) produce lower patient satisfaction and inferior care. We sought to determine whether socioeconomic factors influence which visits are assigned to hallway beds, independent of clinical characteristics at triage.METHODS: We studied 332,919 visits, across 189,326 patients, to two academic EDs from 2013-2016. We estimated a logistic model of hallway bed assignment, conditioning on payor, demographics, triage acuity, chief complaint, patient visit frequency, and ED volume. Because payor is not generally known at the time of triage, we interpreted it as a proxy for other observable characteristics that may influence bed assignment. We estimated a Cox proportional hazards model of hallway bed assignment on length of stay.RESULTS: Median patient age was 53. 54.0% of visits were by women. 42.1% of visits were paid primarily by private payors, 37.1% by Medicare, and 20.7% by Medicaid. A total of 16.2% of visits were assigned to hallway beds. Hallway bed assignment was more likely for frequent ED visitors, for lower acuity presentations, and for psychiatric, substance use, and musculoskeletal chief complaints, which were more common among visits paid primarily by Medicaid. In a logistic model controlling for these factors, as well as for other patient demographics and for the volume of recent ED arrivals, Medicaid status was nevertheless associated with 22% greater odds of assignment to a hallway bed (odds ratio 1.22, [95% confidence interval, CI, 1.18-1.26]), compared to private insurance. Visits assigned to hallway beds had longer lengths of stay than roomed visits of comparable acuity (hazard ratio for departure 0.91 [95% CI, 0.90-0.92]).CONCLUSION: We find evidence of social determinants of hallway bed use, likely involving epidemiologic, clinical, and operational factors. Even after accounting for different distributions of chief complaints and for more frequent ED use by the Medicaid population, as well as for other visit characteristics known at the time of triage, visits paid primarily by Medicaid retain a disproportionate association with hallway bed assignment. Further research is needed to eliminate potential bias in the use of hallway beds. [West J Emerg Med. 2020;21(4)949-958.].
View details for DOI 10.5811/westjem.2020.4.45976
View details for PubMedID 32726269
- Rates of Co-infection Between SARS-CoV-2 and Other Respiratory Pathogens. JAMA 2020
Emergency department implementation of abbreviated magnetic resonance imaging for pediatric traumatic brain injury.
Journal of the American College of Emergency Physicians open
2020; 1 (5): 994–99
Pediatric head injury is a common presenting complaint in the emergency department (ED), often requiring neuroimaging or ED observation for diagnosis. However, the traditional diagnostic neuroimaging modality, head computed tomography (CT), is associated with radiation exposure while prolonged ED observation impacts patient flow and resource utilization. Recent scientific literature supports abbreviated, or focused and shorter, brain magnetic resonance imaging (MRI) as a feasible and accurate diagnostic alternative to CT for traumatic brain injury. However, this is a relatively new application and its use is not widespread. The aims of this review are to describe the science and applications of abbreviated brain MRI and report a model protocol's development and ED implementation in the evaluation of children with head injury for replication in other institutions.
View details for DOI 10.1002/emp2.12055
View details for PubMedID 33145550
View details for PubMedCentralID PMC7593499
Characteristics of Emergency Department Patients With COVID-19 at a Single Site in Northern California: Clinical Observations and Public Health Implications.
Academic emergency medicine : official journal of the Society for Academic Emergency Medicine
In December 2019, a novel coronavirus disease (COVID-19) emerged in Wuhan, China and spread globally, resulting in the first World Health Organization (WHO) classified pandemic in over a decade.1 As of April 2020, the United States (US) has the most confirmed COVID-19 cases worldwide, but public health interventions and testing availability have varied across the country. 2.
View details for DOI 10.1111/acem.14003
View details for PubMedID 32344458
Paramedic Detection of Large Vessel Occlusions Using mNIHSS: A Prospective Cohort Pilot Study.
LIPPINCOTT WILLIAMS & WILKINS. 2019
View details for Web of Science ID 000478733401029
Introduction of a Horizontal and Vertical Split Flow Model of Emergency Department Patients as a Response to Overcrowding.
Journal of emergency nursing: JEN : official publication of the Emergency Department Nurses Association
ED overcrowding is an issue that is affecting every emergency department and every hospital. The inability to maintain patient flow into and out of the emergency department paralyzes the ability to provide effective and timely patient care. Many solutions have been proposed on how to mitigate the effects of ED overcrowding. Solutions involve either hospital-wide initiatives or ED-based solutions. In this article, the authors seek to describe and provide metrics for a patient flow methodology that targets ESI 3 patients in a vertical flow model.In the Stanford Emergency Department, a vertical flow model was created from existing ED space by removing fold-down horizontal stretchers and replacing them with multiple chairs that allowed for assessment and medical management in an upright sitting position. The model was launched and sustained through frequent interdisciplinary huddles, detailed inclusion and exclusion criteria, scripted text on how to promote the flow model to patients, and close analytics of metrics. Metrics for success included patient length of stay (LOS) for those triaged to the vertical flow area compared with ESI 3 patients triaged to the traditional emergency department as a comparison group. The secondary outcome is the total number of patients seen in the vertical flow area. This was a 6-month-September 2014, to February 2015-retrospective pre- and postintervention study that examined LOS as a marker for effective launch and implementation of a vertical patient workflow model.The patients triaged to the vertical flow area in the study period tended to be younger than in the control period (43 years versus 52 years, P = 0.00). There was a significant decrease in our primary end point: the total LOS for ESI 3 patients triaged to the vertical flow area (270 minutes versus 384 minutes, P = 0.00).Implementation of a vertical patient flow strategy can decrease LOS for the vertical ESI 3 patients based upon the inclusion and exclusion criteria. Furthermore, this is accomplished with minimal financial investment within the physical constraints of an existing emergency department.
View details for DOI 10.1016/j.jen.2017.10.017
View details for PubMedID 29169818
The expanded scope of emergency medical practice necessary for initial disaster response: lessons from Haiti.
Journal of special operations medicine : a peer reviewed journal for SOF medical professionals
2012; 12 (1): 31-36
A team of emergency physicians and nurses from Stanford University responded to the devastating January 2010 earthquake in Haiti. Because of the extreme nature of the situation, combined with limited resources, the team provided not only acute medical and surgical care to critically injured and ill victims, but was required to uniquely expand its scope of practice. Using a narrative format and discussion, it is the purpose of this paper to highlight our experience in Haiti and use these to estimate some of the skills and capabilities that will be useful for physicians who respond to similar future disasters.
View details for PubMedID 22427047
- Civil-Military Collaboration in the Initial Medical Response to the Earthquake in Haiti NEW ENGLAND JOURNAL OF MEDICINE 2010; 362 (10)
Immune-Based Resistance to the Formation of v-src-lnduced Distal Tumors
1993; 197 (1): 480-484
Although v-src, the oncogene of Rous sarcoma virus, has been shown to be capable of inducing lethal tumors at visceral sites distal to the primary tumor mass, the mechanisms opposing visceral tumor formation remain to be elucidated. In the present study, we show that visceral tumors, many of which represent a metastasis spawned by the primary mass, are found only in hosts exhibiting reduced levels of tumor immunity. We conclude that it is the weakness of the tumor immune response, rather than a lack of expression of tumor antigen on visceral tumor cells, that is a major underpinning of the formation of v-src-induced visceral tumors.
View details for DOI 10.1006/viro.1993.1617
Pion absorption in light nuclei
Phys. Rev. C
1992; 46 (1): 273-278
View details for DOI 10.1103/PhysRevC.46.273
Energy dependence of the total 12C(π+, 2p) cross section
Physics Letters B
1992; 278 (4): 419-422
View details for DOI 10.1016/0370-2693(92)90578-R
Cluster-impact-fusion yields: No collective effect observed for small water clusters
Phys. Rev. Lett.
1991; 67 (25): 3567-3570
View details for DOI 10.1103/PhysRevLett.67.3567