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Dive into the research topics where Mark I. Langdorf is active.

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Featured researches published by Mark I. Langdorf.


Academic Emergency Medicine | 2011

Test characteristics of focused assessment of sonography for trauma for clinically significant abdominal free fluid in pediatric blunt abdominal trauma.

J. Christian Fox; Megan Boysen; Laleh Gharahbaghian; Seric Cusick; Suleman S. Ahmed; Craig L. Anderson; Michael Lekawa; Mark I. Langdorf

OBJECTIVES Focused assessment of sonography in trauma (FAST) has been shown useful to detect clinically significant hemoperitoneum in adults, but not in children. The objectives were to determine test characteristics for clinically important intraperitoneal free fluid (FF) in pediatric blunt abdominal trauma (BAT) using computed tomography (CT) or surgery as criterion reference and, second, to determine the test characteristics of FAST to detect any amount of intraperitoneal FF as detected by CT. METHODS This was a prospective observational study of consecutive children (0-17 years) who required trauma team activation for BAT and received either CT or laparotomy between 2004 and 2007. Experienced physicians performed and interpreted FAST. Clinically important FF was defined as moderate or greater amount of intraperitoneal FF per the radiologist CT report or surgery. RESULTS The study enrolled 431 patients, excluded 74, and analyzed data on 357. For the first objective, 23 patients had significant hemoperitoneum (22 on CT and one at surgery). Twelve of the 23 had true-positive FAST (sensitivity = 52%; 95% confidence interval [CI] = 31% to 73%). FAST was true negative in 321 of 334 (specificity = 96%; 95% CI = 93% to 98%). Twelve of 25 patients with positive FAST had significant FF on CT (positive predictive value [PPV] = 48%; 95% CI = 28% to 69%). Of 332 patients with negative FAST, 321 had no significant fluid on CT (negative predictive value [NPV] = 97%; 95% CI = 94% to 98%). Positive likelihood ratio (LR) for FF was 13.4 (95% CI = 6.9 to 26.0) while the negative LR was 0.50 (95% CI = 0.32 to 0.76). Accuracy was 93% (333 of 357, 95% CI = 90% to 96%). For the second objective, test characteristics were as follows: sensitivity = 20% (95% CI = 13% to 30%), specificity = 98% (95% CI = 95% to 99%), PPV = 76% (95% CI = 54% to 90%), NPV = 78% (95% CI = 73% to 82%), positive LR = 9.0 (95% CI = 3.7 to 21.8), negative LR = 0.81 (95% CI = 0.7 to 0.9), and accuracy = 78% (277 of 357, 95% CI = 73% to 82%). CONCLUSION In this population of children with BAT, FAST has a low sensitivity for clinically important FF but has high specificity. A positive FAST suggests hemoperitoneum and abdominal injury, while a negative FAST aids little in decision-making.


Annals of Emergency Medicine | 1990

Computerized tracking of emergency medicine resident clinical experience

Mark I. Langdorf; Gary R Strange; Philip Macneil

Although we commonly assume that because residents spend a given number of months in the emergency department they achieve adequate exposure to all necessary clinical entities, this has never been shown. We suspect, rather, that great variability exists among residents in the number and variety of patients they see; and that with respect to the ED, there are important diagnoses that are rare or absent in the clinical pathology of a training program. To confirm these hypotheses, we implemented a computerized system of recording patients and diagnoses managed in the ED by the 33 residents of the University of Illinois Affiliated Hospitals Emergency Medicine Residency. We collected data for nine months and accumulated 2,152 shifts of clinical experience. These data confirm our hypotheses. We found that senior residents managed an average of 11.9 +/- 2.3 patients per ten-hour shift, but the quickest resident saw almost twice as many patients as the slowest. Junior residents saw fewer patients, 8.5 +/- 1.4 patients per shift, but maintained a twofold difference between the fastest and slowest. Furthermore, there are important diagnoses that present too rarely for each resident to become facile in their management. We found that 22.7% of the 554 diagnoses listed in the Emergency Medicine Core Content never once presented to the ED. An additional 34.7% of these diagnoses did present, but so rarely that each resident could not possibly manage one case during a residency. The Length of Training Report of the American College of Emergency Physicians provides objective guidelines for the number of encounters a resident should have with 283 clinical entities. In this study, residents fell short of these guidelines with 50.5% of diagnoses. While absolute quantity of exposure does not assure competence in management, we recommend that each residency monitor the experience of its residents. This allows a residency to change its curriculum to make optimum use of available pathology, as well as to supplement deficiencies in clinical experience with case simulations.


Journal of Emergency Medicine | 1998

Quantification of Procedures and Resuscitations in an Emergency Medicine Residency

Mark I. Langdorf; Brian J. Montague; Brian Bearie; Craig S Sobel

Currently, there are no data that govern the number of procedures that are necessary to promote competence during emergency medicine (EM) training. Nonetheless, the Residency Review Committee requires each program to report the average number of procedures and resuscitations performed by its residents. For 7 years, we have used a computer database to track resuscitation and procedure experience for 42 residents. We have documented resident experience both in our 36,000-visit Level I Trauma Center emergency department and during off-service rotations in our 400-bed university teaching hospital. We report data from four graduating classes (n = 24). We estimate that residents have recorded 60% of the actual procedures performed. The 24 residents documented 11,947 procedures, averaging 498 per resident (range 264-1055), and participated in 3432 resuscitations, or 143 per resident (range 64-379). Mean and standard deviations are reported for 20 specific EM procedures and 4 types of resuscitations. EM residents perform a large number of procedures, but there is wide inter-resident variability. There is no documentation that some residents perform even one of some rare but critical procedures. This tracking system suggests, then, that procedure simulations, or cadaver and animal models, must be developed and used to enhance experience. This program can be modified to track resident experience in any specialty, as well as to document supervision by faculty and support credentialling inquiries.


Annals of Emergency Medicine | 2015

Prevalence and clinical import of thoracic injury identified by chest computed tomography but not chest radiography in blunt trauma: Multicenter prospective cohort study presented at the western regional society for academic emergency medicine meeting, March 2014, Irvine, CA; And the Society for Academic Emergency Medicine national meeting, May 2014, Dallas, TX.

Mark I. Langdorf; Anthony J. Medak; Gregory W. Hendey; Daniel K. Nishijima; William R. Mower; Ali S. Raja; Brigitte M. Baumann; Deirdre Anglin; Craig L. Anderson; Shahram Lotfipour; Karin E. Reed; Nadia Zuabi; Nooreen A. Khan; Chelsey A. Bithell; Armaan A. Rowther; Julian Villar; Robert M. Rodriguez

STUDY OBJECTIVE Chest computed tomography (CT) diagnoses more injuries than chest radiography, so-called occult injuries. Wide availability of chest CT has driven substantial increase in emergency department use, although the incidence and clinical significance of chest CT findings have not been fully described. We determine the frequency, severity, and clinical import of occult injury, as determined by changes in management. These data will better inform clinical decisions, need for chest CT, and odds of intervention. METHODS Our sample included prospective data (2009 to 2013) on 5,912 patients at 10 Level I trauma center EDs with both chest radiography and chest CT at physician discretion. These patients were 40.6% of 14,553 enrolled in the parent study who had either chest radiography or chest CT. Occult injuries were pneumothorax, hemothorax, sternal or greater than 2 rib fractures, pulmonary contusion, thoracic spine or scapula fracture, and diaphragm or great vessel injury found on chest CT but not on preceding chest radiography. A priori, we categorized thoracic injuries as major (having invasive procedures), minor (observation or inpatient pain control >24 hours), or of no clinical significance. Primary outcome was prevalence and proportion of occult injury with major interventions of chest tube, mechanical ventilation, or surgery. Secondary outcome was minor interventions of admission rate or observation hours because of occult injury. RESULTS Two thousand forty-eight patients (34.6%) had chest injury on chest radiography or chest CT, whereas 1,454 of these patients (71.0%, 24.6% of all patients) had occult injury. Of these, in 954 patients (46.6% of injured, 16.1% of total), chest CT found injuries not observed on immediately preceding chest radiography. In 500 more patients (24.4% of injured patients, 8.5% of all patients), chest radiography found some injury, but chest CT found occult injury. Chest radiography found all injuries in only 29.0% of injured patients. Two hundred and two patients with occult injury (of 1,454, 13.9%) had major interventions, 343 of 1,454 (23.6%) had minor interventions, and 909 (62.5%) had no intervention. Patients with occult injury included 514 with pulmonary contusions (of 682 total, 75.4% occult), 405 with pneumothorax (of 597 total, 67.8% occult), 184 with hemothorax (of 230 total, 80.0% occult), those with greater than 2 rib fractures (n=672/1,120, 60.0% occult) or sternal fracture (n=269/281, 95.7% occult), 12 with great vessel injury (of 18 total, 66.7% occult), 5 with diaphragm injury (of 6, 83.3% occult), and 537 with multiple occult injuries. Interventions for patients with occult injury included mechanical ventilation for 31 of 514 patients with pulmonary contusion (6.0%), chest tube for 118 of 405 patients with pneumothorax (29.1%), and 75 of 184 patients with hemothorax (40.8%). Inpatient pain control or observation greater than 24 hours was conducted for 183 of 672 patients with rib fractures (27.2%) and 79 of 269 with sternal fractures (29.4%). Three of 12 (25%) patients with occult great vessel injuries had surgery. Repeated imaging was conducted for 50.6% of patients with occult injury (88.1% chest radiography, 11.9% chest CT, 7.5% both). For patients with occult injury, 90.9% (1,321/1,454) were admitted, with 9.1% observed in the ED for median 6.9 hours. Forty-four percent of observed patients were then admitted (4.0% of patients with occult injury). CONCLUSION In a more seriously injured subset of patients with blunt trauma who had both chest radiography and chest CT, occult injuries were found by chest CT in 71% of those with thoracic injuries and one fourth of all those with blunt chest trauma. More than one third of occult injury had intervention (37.5%). Chest tubes composed 76.2% of occult injury major interventions, with observation or inpatient pain control greater than 24 hours in 32.4% of occult fractures. Only 1 in 20 patients with occult injury was discharged home from the ED. For these patients with blunt trauma, chest CT is useful to identify otherwise occult injuries.


American Journal of Emergency Medicine | 2009

The worsening of ED on-call coverage in California: 6-year trend

Scott E. Rudkin; Mark I. Langdorf; Jennifer A. Oman; Christopher A. Kahn; Hayley White; Craig L. Anderson

To reassess problems with on-call physician coverage in California, we repeated our anonymous 2000 survey of the California chapter of the American College of Emergency Physicians. Physicians responded from 77.4% of California emergency departments (EDs), 51.0% of ED directors, and 34% of those surveyed. Of 21 specialties, on-call availability worsened since 2000 for 9, was unchanged for 11, and improved for 1. Of ED directors, 54% report medical staff rules require on-call duty, down from 72% in 2000. Hospitals have increased specialist on-call payments (from 21% to 35%, with 75% paying at least one specialty). Most emergency physicians (80.3%) report insurance status negatively affects on-call physician responsiveness, up from 42% in 2000. Emergency departments with predominantely minority or uninsured patients had fewer specialists and more trouble accessing them. Insurance status has a major negative effect on ED consultation and follow-up care. The on-call situation in California has worsened substantially in 6 years.


Prehospital and Disaster Medicine | 2006

Success and complication rates with prehospital placement of an esophageal-tracheal combitube as a rescue airway.

Thomas R. Calkins; Kenneth L. Miller; Mark I. Langdorf

INTRODUCTION Previous studies have proven the success of the Esophageal-Tracheal Combitube (ETC) as a primary airway, but not as a rescue airway. OBJECTIVE The object of this study was to observe success and complication rates of paramedic placement of an ETC as a rescue airway, and to compare success rates with endotracheal tube (ETT) intubation. The primary outcome indicator was placement with successful ventilation. Complication rates, esophageal placement, and return of spontaneous circulation (ROSC) were secondary measures. METHODS A retrospective review of the records of patients who had ETC attempts by Emergency Medical Services (EMS) was conducted for a period of three years. Complications were defined a priori. The ETC is used primarily as rescue airway for a failed attempt at an endotracheal tube (ETT) intubation. A control group for ETT placements was drawn from the EMS quality assurance (QA) database for the same period. RESULTS Esophageal-Tracheal Combitube insertion was attempted on 162 patients, of which, 113 (70%) were successful, 46 (28%) failed, and the outcome of three (2%) was not recorded. Inability to place the ETC occurred in 29 (18%) patients, and accounted for 48% (22/46) of failures. The use of the ETC caused dental trauma in one patient, and one placement of the ETC was related to the onset of subcutaneous emphysema. Blood in the ETC from active upper gatrointestinal bleeding occurred in nine patients (6%), and four tubes (3%) became dislodged en route to the hospital. The apriori complication rate was 44/162 (27%). Inability to determine placement of the ETC due to emesis from both ports occurred in 21 cases. Combining these problems with the apriori complications, the overall rate was 40% (65/162). Esophageal-Tracheal Combitube location was noted in a subset of 90 charts, of which, 76 (84%) were esophageal, and 14 (16%) were tracheal. Thirteen of 126 (10%) patients in cardiac arrest had return of spontaneous circulation (ROSC) in the field after placement of the ETC. An ETT was attempted in 128 control patients, of which, 107 (84%) were successful, 21 (16%) failed (odds ratio (OR) for ETT vs. ETC = 2.1; 95% CI = 1.12-3.86). CONCLUSION Despite a low ROSC rate, the complication and success rates of ETC are acceptable for a rescue airway device. Tracheal placement of the Combitube is uncommon, but requires fail-safe discrimination. Similar to previous reports, the success ratio for ETT was greater than for the ETC.


PLOS Medicine | 2015

Derivation and validation of two decision instruments for selective chest CT in blunt trauma: a multicenter prospective observational study (NEXUS Chest CT).

Robert M. Rodriguez; Mark I. Langdorf; Daniel K. Nishijima; Brigitte M. Baumann; Gregory W. Hendey; Anthony J. Medak; Ali S. Raja; Isabel E. Allen; William R. Mower

Background Unnecessary diagnostic imaging leads to higher costs, longer emergency department stays, and increased patient exposure to ionizing radiation. We sought to prospectively derive and validate two decision instruments (DIs) for selective chest computed tomography (CT) in adult blunt trauma patients. Methods and Findings From September 2011 to May 2014, we prospectively enrolled blunt trauma patients over 14 y of age presenting to eight US, urban level 1 trauma centers in this observational study. During the derivation phase, physicians recorded the presence or absence of 14 clinical criteria before viewing chest imaging results. We determined injury outcomes by CT radiology readings and categorized injuries as major or minor according to an expert-panel-derived clinical classification scheme. We then employed recursive partitioning to derive two DIs: Chest CT-All maximized sensitivity for all injuries, and Chest CT-Major maximized sensitivity for only major thoracic injuries (while increasing specificity). In the validation phase, we employed similar methodology to prospectively test the performance of both DIs. We enrolled 11,477 patients—6,002 patients in the derivation phase and 5,475 patients in the validation phase. The derived Chest CT-All DI consisted of (1) abnormal chest X-ray, (2) rapid deceleration mechanism, (3) distracting injury, (4) chest wall tenderness, (5) sternal tenderness, (6) thoracic spine tenderness, and (7) scapular tenderness. The Chest CT-Major DI had the same criteria without rapid deceleration mechanism. In the validation phase, Chest CT-All had a sensitivity of 99.2% (95% CI 95.4%–100%), a specificity of 20.8% (95% CI 19.2%–22.4%), and a negative predictive value (NPV) of 99.8% (95% CI 98.9%–100%) for major injury, and a sensitivity of 95.4% (95% CI 93.6%–96.9%), a specificity of 25.5% (95% CI 23.5%–27.5%), and a NPV of 93.9% (95% CI 91.5%–95.8%) for either major or minor injury. Chest CT-Major had a sensitivity of 99.2% (95% CI 95.4%–100%), a specificity of 31.7% (95% CI 29.9%–33.5%), and a NPV of 99.9% (95% CI 99.3%–100%) for major injury and a sensitivity of 90.7% (95% CI 88.3%–92.8%), a specificity of 37.9% (95% CI 35.8%–40.1%), and a NPV of 91.8% (95% CI 89.7%–93.6%) for either major or minor injury. Regarding the limitations of our work, some clinicians may disagree with our injury classification and sensitivity thresholds for injury detection. Conclusions We prospectively derived and validated two DIs (Chest CT-All and Chest CT-Major) that identify blunt trauma patients with clinically significant thoracic injuries with high sensitivity, allowing for a safe reduction of approximately 25%–37% of unnecessary chest CTs. Trauma evaluation protocols that incorporate these DIs may decrease unnecessary costs and radiation exposure in the disproportionately young trauma population.


CJEM | 2001

Motivations for a career in emergency medicine: a profile of the 1996 US applicant pool.

Amin Antoine Kazzi; Mark I. Langdorf; Delaram Ghadishah; Neal Handly

INTRODUCTION Although some studies have tried to assess the factors leading to choice of specialty, none have been specific to emergency medicine (EM). With a doubling of the number of EM residency programs in the past decade, an assessment of the career motivations of residents is in order. OBJECTIVES To identify and rank the factors that lead candidates to choose EM as a career. METHODS Fifty-four participating EM programs returned a total of 393 anonymous surveys completed by their 1996 National Residency Matching Program (NRMP) interviewees. The survey asked respondents to rank 12 factors on a 5-point (0-4) Likert scale. RESULTS Respondents ranked the 12 motivating factors in the following descending order of importance: diversity in clinical pathology, emphasis on acute care, flexibility in choice of practice location, flexibility of EM work schedules, previous work experience in EM, greater availability of EM faculty for bedside teaching, strong influence of an EM faculty advisor or mentor, relatively shorter length of training, better salaries for EM than for primary care specialties, the presence of an EM residency at the students medical school, perception that EM residents have more time to moonlight and popularity of EM among medical students. CONCLUSION US applicants appear to choose a career in EM largely because of clinical factors (diversity of clinical pathology and emphasis on acute care) and practice-related factors (flexibility in practice location and schedule).


Prehospital and Disaster Medicine | 2000

Earthquake epidemiology : The 1994 Los Angeles earthquake emergency department experience at a community hospital

A. Antoine Kazzi; Mark I. Langdorf; Neal Handly; Karen White; Ken Ellis

INTRODUCTION To assess the volume of patients and the composition of their injuries and illnesses that presented to an emergency department (ED) close to the epicenter of an earthquake that occurred in a seismically prepared area. METHODS A retrospective analysis of data abstracted from charts and ED logs for patient census and types of injuries and illnesses of the patients who presented in the ED of a community hospital before and after the earthquake (6.8 Richter scale) that occurred in 1994 in Los Angeles. Illnesses were classified as trauma- and non-trauma related. Data were compared with epidemiological profiles of earthquakes in seismically prepared and unprepared areas. RESULTS A statistically significant increase in ED patient census over baseline lasted 11 days. There was a large increase in the number of traumatic injuries such as lacerations and orthopedic injuries during the first 48 hours. Beginning on the third day after the event, primary care conditions predominated. When the effects of the LA quake were compared with those of similar Richter magnitude and disruptive capability, the ED epidemiology profile was similar to those in seismically unprepared areas, except for the total number of casualties. CONCLUSION The majority of patients with traumatic injuries presented within the first 48 hours. The increase relative to baseline lasted 11 days. Efforts to develop disaster response systems from resources outside the disaster-stricken area should focus on providing mostly primary care assistance. Communities in seismically prepared areas could require external medical assistance for their EDs for up to two weeks following the event.


Western Journal of Emergency Medicine | 2015

Ultrafest: A Novel Approach to Ultrasound in Medical Education Leads to Improvement in Written and Clinical Examinations

Kiah Connolly; Lancelot Beier; Mark I. Langdorf; Craig L. Anderson; John Christian Fox

Introduction Our objective was to evaluate the effectiveness of hands-on training at a bedside ultrasound (US) symposium (“Ultrafest”) to improve both clinical knowledge and image acquisition skills of medical students. Primary outcome measure was improvement in multiple choice questions on pulmonary or Focused Assessment with Sonography in Trauma (FAST) US knowledge. Secondary outcome was improvement in image acquisition for either pulmonary or FAST. Methods Prospective cohort study of 48 volunteers at “Ultrafest,” a free symposium where students received five contact training hours. Students were evaluated before and after training for proficiency in either pulmonary US or FAST. Proficiency was assessed by clinical knowledge through written multiple-choice exam, and clinical skills through accuracy of image acquisition. We used paired sample t-tests with students as their own controls. Results Pulmonary knowledge scores increased by a mean of 10.1 points (95% CI [8.9–11.3], p<0.00005), from 8.4 to a posttest average of 18.5/21 possible points. The FAST knowledge scores increased by a mean of 7.5 points (95% CI [6.3–8.7] p<0.00005), from 8.1 to a posttest average of 15.6/21. We analyzed clinical skills data on 32 students. The mean score was 1.7 pretest and 4.7 posttest of 12 possible points. Mean improvement was 3.0 points (p<0.00005) overall, 3.3 (p=0.0001) for FAST, and 2.6 (p=0.003) for the pulmonary US exam. Conclusion This study suggests that a symposium on US can improve clinical knowledge, but is limited in achieving image acquisition for pulmonary and FAST US assessments. US training external to official medical school curriculum may augment students’ education.

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