Introduction Nonoperative management of hemodynamically stable patients with blunt splenic and/or... more Introduction Nonoperative management of hemodynamically stable patients with blunt splenic and/or hepatic injury has been widely accepted in the pediatric population. However, variability exists in the utilization and timing of repeat imaging to assess for delayed complications during index hospitalization. Recent level-IV evidence suggests that repeat imaging in children should be performed based on a patient’s clinical status rather than on a routine basis. The aim of this study is to examine the rate of delayed complications and interventions in pediatric trauma patients with blunt splenic and/or hepatic injuries who undergo repeat imaging prompted either by a clinical change (CC) or non-clinical change (NCC). Methods A 9-year (2011-2019), retrospective, dual-institution study was performed of children (0-17 years) with blunt splenic and/or hepatic injuries. Patients were grouped based on reason for repeat imaging: CC or NCC. The rate of organ-specific delayed complications and i...
OBJECTIVE This study examined differences in clinical and resuscitation characteristics between i... more OBJECTIVE This study examined differences in clinical and resuscitation characteristics between injured children with and without severe traumatic brain injury (sTBI) and aimed to identify resuscitation characteristics associated with improved outcomes following sTBI. METHODS This is a post hoc analysis of a prospective observational study of injured children younger than 18 years (2018–2019) transported from the scene, with elevated shock index pediatric-adjusted on arrival and head Abbreviated Injury Scale score of ≥3. Timing and volume of resuscitation products were assessed using χ2 t test, Fisher's exact t test, Kruskal-Wallis, and multivariable logistic regression analyses. RESULTS There were 142 patients with sTBI and 547 with non-sTBI injuries. Severe traumatic brain injury patients had lower initial hemoglobin (11.3 vs. 12.4, p < 0.001), greater initial international normalized ratio (1.4 vs. 1.1, p < 0.001), greater Injury Severity Score (25 vs. 5, p < 0.001),...
BACKGROUND The purpose of this study was to determine the relationship between timing and volume ... more BACKGROUND The purpose of this study was to determine the relationship between timing and volume of crystalloid before blood products and mortality, hypothesizing that earlier transfusion and decreased crystalloid before transfusion would be associated with improved outcomes. METHODS A multi-institutional prospective observational study of pediatric trauma patients younger than 18 years, transported from the scene of injury with elevated age-adjusted shock index on arrival, was performed from April 2018 to September 2019. Volume and timing of prehospital, emergency department, and initial admission resuscitation were assessed including calculation of 20 ± 10 mL/kg crystalloid boluses overall and before transfusion. Multivariable Cox proportional hazards and logistic regression models identified factors associated with mortality and extended intensive care, ventilator, and hospital days. RESULTS In 712 children at 24 trauma centers, mean age was 7.6 years, median (interquartile range...
Additional file 5. Post-hoc tests from Univariate Anovas comparing frequency of strain reported b... more Additional file 5. Post-hoc tests from Univariate Anovas comparing frequency of strain reported by the different professions, across all types of operations.
Proceedings of the Human Factors and Ergonomics Society Annual Meeting
Context dependent gaze metrics, derived from eye movements explicitly associated with how a task ... more Context dependent gaze metrics, derived from eye movements explicitly associated with how a task is being performed, are particularly useful for formative assessment that includes feedback on specific behavioral adjustments for skill acquisitions. In laparoscopic surgery, context dependent gaze metrics are under investigated and commonly derived by either qualitatively inspecting the videos frame by frame or mapping the fixations onto a static surgical task field. This study collected eye-tracking and video data from 13 trainees practicing the peg transfer task. Machine learning algorithms in computer vision were employed to derive metrics of tool speed, fixation rate on (moving or stationary) target objects, and fixation rate on tool-object combination. Preliminary results from a clustering analysis on the measurements from 499 practice trials indicated that the metrics were able to differentiate three skill levels amongst the trainees, suggesting high sensitivity and potential of ...
Team familiarity has been shown to be important for operative efficiency and number of complicati... more Team familiarity has been shown to be important for operative efficiency and number of complications, but it is unclear for which types of operations and for which team members familiarity matters the most. The objective of this study is to further our understanding of familiarity in the OR by quantifying the relative importance of familiarity among all possible core team dyads, and defining the impact of team level familiarity on outcomes. Using a retrospective chart and administrative data review, five years of data from two health systems (14 hospitals) and across two procedures, (knee arthroplasty and lumbar laminectomy) were included. Multilevel modeling approach and a dominance analysis were conducted. For each previous surgery that any two members of the core surgical team had participated in together, the length of surgery decreased significantly. The familiarity of the scrub and the surgeon was the most significant relationship for knee arthroplasty across the two hospitals, and laminectomies at one hospital. The relationship between familiarity of the surgical team and surgical efficiency may be more complex than previously articulated. Familiarity may be more important for certain types of procedures. The familiarity of certain dyads may be more important for certain types of procedures.
Background Strain episodes, defined as phases of higher workload, stress or negative emotions, oc... more Background Strain episodes, defined as phases of higher workload, stress or negative emotions, occur everyday in the operating room (OR). Accurate knowledge of when strain is most intense for the different OR team members is imperative for developing appropriate interventions. The primary goal of the study was to investigate temporal patterns of strain across surgical phases for different professionals working in the OR, for different types of operations. Methods We developed a guided recall method to assess the experience of strain from the perspective of operating room (OR) team members. The guided recall was completed by surgeons, residents, anesthesiologists, circulating nurses and scrub technicians immediately after 113 operations, performed in 5 departments of one hospital in North America. We also conducted interviews with 16 surgeons on strain moments during their specific operation types. Strain experiences were related to surgical phases and compared across different opera...
BackgroundEye-gaze metrics derived from areas of interest (AOIs) have been suggested to be effect... more BackgroundEye-gaze metrics derived from areas of interest (AOIs) have been suggested to be effective for surgical skill assessment. However, prior research is mostly based on static images and simulated tasks that may not translate to complex and dynamic surgical scenes. Therefore, eye-gaze metrics must advance to account for changes in the location of important information during a surgical procedure.MethodsWe developed a dynamic AOI generation technique based on eye gaze collected from an expert viewing surgery videos. This AOI updated as the gaze of the expert moved with changes in the surgical scene. This technique was evaluated through an experiment recruiting a total of 20 attendings and residents to view 10 videos associated with and another 10 without adverse events.ResultsDwell time percentage (i.e., gaze duration) inside the AOI differentiated video type (U = 13508.5, p < 0.001) between videos with the presence (Mdn = 16.75) versus absence (Mdn = 19.95) of adverse events. This metric also differentiated participant group (U = 14029.5, p < 0.001) between attendings (Mdn = 15.45) and residents (Mdn = 19.80). This indicates that our dynamic AOIs reflecting the expert eye gaze was able to differentiate expertise, and the presence of unexpected adverse events.ConclusionThis dynamic AOI generation technique produced dynamic AOIs for deriving eye-gaze metrics that were sensitive to expertise level and event characteristics.
Combat casualties have endured an increase in traumatic lower extremity amputations secondary to ... more Combat casualties have endured an increase in traumatic lower extremity amputations secondary to improvised explosive devices. Often surgical control of the proximal vasculature is required. We evaluate the safety profile of exploratory laparotomy (EXLAP) for proximal control (PC) in combat-injured patients. Records of 845 combat casualties from June 2009 to December 2011 were reviewed. Patients undergoing EXLAP were divided by indication into PC and non-PC groups. Demographics, Injury Severity Score, mechanism of injury, transfusion requirements, EXLAP findings, reoperation rates, and abdominal-related complications were recorded. 44 patients were identified as PC and 91 as non-PC. Age was similar (23.7 ± 4.1 vs. 24.0 ± 4.6, p = 0.7138), and all were male. Improvised explosive devices blast was the most common mechanism of injury. Injury Severity Score (25.8 ± 8.2 vs. 21.4 ± 9.1, p = 0.0075), lower extremity amputation (93.1% vs. 28.6%, p = 0.0001), and transfusion requirements wer...
Gekkonoid lizards increase in body size throughout life, and the present study investigates wheth... more Gekkonoid lizards increase in body size throughout life, and the present study investigates whether changes in auditory function accompany these increases. Middle-ear structures in four groups of animals, adults and juveniles of two gekkonoid species (Eublepharis macularius and Oedura marmorata), were examined. Tympanic membrane velocity and phase were also measured in all four groups. An indication of peripheral auditory function was obtained for each group by measuring compound action potentials (CAPs) from the round window membrane. The middleear contribution to CAP thresholds was obtained by comparing threshold levels of the CAP response with and without an intact middle-ear system. The results from these studies indicated that significant changes occurred in middle-ear structure, tympanic membrane velocity and CAP threshold between the younger and older animals. In addition, the adults of both species exhibited better auditory function when the acoustic stimulus was delivered to the tympanic membrane than when it was delivered to the columella footplate. The findings show clearly that increased body size (or age) is accompanied by functional changes in the auditory periphery.
Introduction Nonoperative management of hemodynamically stable patients with blunt splenic and/or... more Introduction Nonoperative management of hemodynamically stable patients with blunt splenic and/or hepatic injury has been widely accepted in the pediatric population. However, variability exists in the utilization and timing of repeat imaging to assess for delayed complications during index hospitalization. Recent level-IV evidence suggests that repeat imaging in children should be performed based on a patient’s clinical status rather than on a routine basis. The aim of this study is to examine the rate of delayed complications and interventions in pediatric trauma patients with blunt splenic and/or hepatic injuries who undergo repeat imaging prompted either by a clinical change (CC) or non-clinical change (NCC). Methods A 9-year (2011-2019), retrospective, dual-institution study was performed of children (0-17 years) with blunt splenic and/or hepatic injuries. Patients were grouped based on reason for repeat imaging: CC or NCC. The rate of organ-specific delayed complications and i...
OBJECTIVE This study examined differences in clinical and resuscitation characteristics between i... more OBJECTIVE This study examined differences in clinical and resuscitation characteristics between injured children with and without severe traumatic brain injury (sTBI) and aimed to identify resuscitation characteristics associated with improved outcomes following sTBI. METHODS This is a post hoc analysis of a prospective observational study of injured children younger than 18 years (2018–2019) transported from the scene, with elevated shock index pediatric-adjusted on arrival and head Abbreviated Injury Scale score of ≥3. Timing and volume of resuscitation products were assessed using χ2 t test, Fisher's exact t test, Kruskal-Wallis, and multivariable logistic regression analyses. RESULTS There were 142 patients with sTBI and 547 with non-sTBI injuries. Severe traumatic brain injury patients had lower initial hemoglobin (11.3 vs. 12.4, p < 0.001), greater initial international normalized ratio (1.4 vs. 1.1, p < 0.001), greater Injury Severity Score (25 vs. 5, p < 0.001),...
BACKGROUND The purpose of this study was to determine the relationship between timing and volume ... more BACKGROUND The purpose of this study was to determine the relationship between timing and volume of crystalloid before blood products and mortality, hypothesizing that earlier transfusion and decreased crystalloid before transfusion would be associated with improved outcomes. METHODS A multi-institutional prospective observational study of pediatric trauma patients younger than 18 years, transported from the scene of injury with elevated age-adjusted shock index on arrival, was performed from April 2018 to September 2019. Volume and timing of prehospital, emergency department, and initial admission resuscitation were assessed including calculation of 20 ± 10 mL/kg crystalloid boluses overall and before transfusion. Multivariable Cox proportional hazards and logistic regression models identified factors associated with mortality and extended intensive care, ventilator, and hospital days. RESULTS In 712 children at 24 trauma centers, mean age was 7.6 years, median (interquartile range...
Additional file 5. Post-hoc tests from Univariate Anovas comparing frequency of strain reported b... more Additional file 5. Post-hoc tests from Univariate Anovas comparing frequency of strain reported by the different professions, across all types of operations.
Proceedings of the Human Factors and Ergonomics Society Annual Meeting
Context dependent gaze metrics, derived from eye movements explicitly associated with how a task ... more Context dependent gaze metrics, derived from eye movements explicitly associated with how a task is being performed, are particularly useful for formative assessment that includes feedback on specific behavioral adjustments for skill acquisitions. In laparoscopic surgery, context dependent gaze metrics are under investigated and commonly derived by either qualitatively inspecting the videos frame by frame or mapping the fixations onto a static surgical task field. This study collected eye-tracking and video data from 13 trainees practicing the peg transfer task. Machine learning algorithms in computer vision were employed to derive metrics of tool speed, fixation rate on (moving or stationary) target objects, and fixation rate on tool-object combination. Preliminary results from a clustering analysis on the measurements from 499 practice trials indicated that the metrics were able to differentiate three skill levels amongst the trainees, suggesting high sensitivity and potential of ...
Team familiarity has been shown to be important for operative efficiency and number of complicati... more Team familiarity has been shown to be important for operative efficiency and number of complications, but it is unclear for which types of operations and for which team members familiarity matters the most. The objective of this study is to further our understanding of familiarity in the OR by quantifying the relative importance of familiarity among all possible core team dyads, and defining the impact of team level familiarity on outcomes. Using a retrospective chart and administrative data review, five years of data from two health systems (14 hospitals) and across two procedures, (knee arthroplasty and lumbar laminectomy) were included. Multilevel modeling approach and a dominance analysis were conducted. For each previous surgery that any two members of the core surgical team had participated in together, the length of surgery decreased significantly. The familiarity of the scrub and the surgeon was the most significant relationship for knee arthroplasty across the two hospitals, and laminectomies at one hospital. The relationship between familiarity of the surgical team and surgical efficiency may be more complex than previously articulated. Familiarity may be more important for certain types of procedures. The familiarity of certain dyads may be more important for certain types of procedures.
Background Strain episodes, defined as phases of higher workload, stress or negative emotions, oc... more Background Strain episodes, defined as phases of higher workload, stress or negative emotions, occur everyday in the operating room (OR). Accurate knowledge of when strain is most intense for the different OR team members is imperative for developing appropriate interventions. The primary goal of the study was to investigate temporal patterns of strain across surgical phases for different professionals working in the OR, for different types of operations. Methods We developed a guided recall method to assess the experience of strain from the perspective of operating room (OR) team members. The guided recall was completed by surgeons, residents, anesthesiologists, circulating nurses and scrub technicians immediately after 113 operations, performed in 5 departments of one hospital in North America. We also conducted interviews with 16 surgeons on strain moments during their specific operation types. Strain experiences were related to surgical phases and compared across different opera...
BackgroundEye-gaze metrics derived from areas of interest (AOIs) have been suggested to be effect... more BackgroundEye-gaze metrics derived from areas of interest (AOIs) have been suggested to be effective for surgical skill assessment. However, prior research is mostly based on static images and simulated tasks that may not translate to complex and dynamic surgical scenes. Therefore, eye-gaze metrics must advance to account for changes in the location of important information during a surgical procedure.MethodsWe developed a dynamic AOI generation technique based on eye gaze collected from an expert viewing surgery videos. This AOI updated as the gaze of the expert moved with changes in the surgical scene. This technique was evaluated through an experiment recruiting a total of 20 attendings and residents to view 10 videos associated with and another 10 without adverse events.ResultsDwell time percentage (i.e., gaze duration) inside the AOI differentiated video type (U = 13508.5, p < 0.001) between videos with the presence (Mdn = 16.75) versus absence (Mdn = 19.95) of adverse events. This metric also differentiated participant group (U = 14029.5, p < 0.001) between attendings (Mdn = 15.45) and residents (Mdn = 19.80). This indicates that our dynamic AOIs reflecting the expert eye gaze was able to differentiate expertise, and the presence of unexpected adverse events.ConclusionThis dynamic AOI generation technique produced dynamic AOIs for deriving eye-gaze metrics that were sensitive to expertise level and event characteristics.
Combat casualties have endured an increase in traumatic lower extremity amputations secondary to ... more Combat casualties have endured an increase in traumatic lower extremity amputations secondary to improvised explosive devices. Often surgical control of the proximal vasculature is required. We evaluate the safety profile of exploratory laparotomy (EXLAP) for proximal control (PC) in combat-injured patients. Records of 845 combat casualties from June 2009 to December 2011 were reviewed. Patients undergoing EXLAP were divided by indication into PC and non-PC groups. Demographics, Injury Severity Score, mechanism of injury, transfusion requirements, EXLAP findings, reoperation rates, and abdominal-related complications were recorded. 44 patients were identified as PC and 91 as non-PC. Age was similar (23.7 ± 4.1 vs. 24.0 ± 4.6, p = 0.7138), and all were male. Improvised explosive devices blast was the most common mechanism of injury. Injury Severity Score (25.8 ± 8.2 vs. 21.4 ± 9.1, p = 0.0075), lower extremity amputation (93.1% vs. 28.6%, p = 0.0001), and transfusion requirements wer...
Gekkonoid lizards increase in body size throughout life, and the present study investigates wheth... more Gekkonoid lizards increase in body size throughout life, and the present study investigates whether changes in auditory function accompany these increases. Middle-ear structures in four groups of animals, adults and juveniles of two gekkonoid species (Eublepharis macularius and Oedura marmorata), were examined. Tympanic membrane velocity and phase were also measured in all four groups. An indication of peripheral auditory function was obtained for each group by measuring compound action potentials (CAPs) from the round window membrane. The middleear contribution to CAP thresholds was obtained by comparing threshold levels of the CAP response with and without an intact middle-ear system. The results from these studies indicated that significant changes occurred in middle-ear structure, tympanic membrane velocity and CAP threshold between the younger and older animals. In addition, the adults of both species exhibited better auditory function when the acoustic stimulus was delivered to the tympanic membrane than when it was delivered to the columella footplate. The findings show clearly that increased body size (or age) is accompanied by functional changes in the auditory periphery.
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