About

Lindsay Nadkarni Shepard is an Assistant Professor of Anesthesiology and Critical Care at the Children's Hospital of Philadelphia. She holds a BA in Biological Basis of Behavior from the University of Pennsylvania, an MD from Sidney Kimmel Medical College at Thomas Jefferson University, and is completing an MSCE in Clinical Epidemiology at the University of Pennsylvania. Her research and clinical interests focus on critical care medicine, with a particular emphasis on pediatric resuscitation, airway management, and physiology-guided CPR. Shepard has contributed to multiple studies related to pediatric cardiac arrest, tracheal intubation, and ventilation, and has been recognized for her work with awards such as the Star Research Award at the Critical Care Congress.

Research topics

• Medicine
• Intensive care medicine
• Psychology
• Emergency medicine
• Medical emergency

Selected publications

• Quality of Bag-Mask Ventilation for Children Before Intubation: Single-Center PICU Pilot Observational Study, 2019–2022

  Pediatric Critical Care Medicine · 2026-03-23 · 1 citations

  articleOpen access1st authorCorresponding

  OBJECTIVES: To characterize the quality of bag-mask ventilation (BMV) before tracheal intubation in children in the PICU and to evaluate the association between poor BMV quality and adverse airway outcomes. DESIGN: Single-center, pilot observational study, 2019-2022. SETTING: Large, urban quaternary care PICU. PATIENTS: Pediatric patients requiring BMV before tracheal intubation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Using a respiratory function monitor, we collected flow and pressure data from 8446 BMV breaths before tracheal intubation in 85 children in the PICU (median age, 3.3 yr [interquartile range, 1.4-8.3 yr]). Adverse airway outcomes (i.e., tracheal intubation-associated event and/or pulse oximetry desaturation < 80%) occurred in 14 of 85 patients (16.5%). Low-quality BMV breaths were defined as: 1) inadequate or excessive exhaled tidal volume (VTe < 4 or > 12 mL/kg); 2) excessive peak inspiratory pressure (PIP) and excessive VTe; 3) excessive facemask leak (> 40%); or 4) failure to relieve upper airway obstruction. Overall, 78.0% of BMV breaths met at least one low-quality criterion; most frequently inadequate or excessive VTe (55.5%), followed by excessive leak (46.2%). Infants (< 1 yr) and young children (1-7 yr), compared with older children (8-17 yr), had a higher proportion of low-quality BMV breaths overall (86.0%, 85.5% vs. 57.9%; p < 0.001 for both), with inadequate or excessive VTe (57.7%, 61.1% vs. 43.7%; p < 0.001 for both), excessive leak (50.6%, 49.2% vs. 37.0%; p < 0.001 for both), and excessive PIP with excessive VTe (17.5%, 19.4% vs. 6.4%; p < 0.001). After controlling for respiratory pathology, low-quality BMV was associated with 2.8-times greater odds of adverse airway outcome (adjusted odds ratio, 2.8 [95% CI, 1.2-6.2]; p = 0.01). CONCLUSIONS: The majority of BMV breaths delivered to children before tracheal intubation in the PICU were of low-quality. And, such breaths, were more frequent in younger children and were associated with greater odds of adverse airway outcomes.

  PublisherOA PDFDOI

• Intubation Trends and Survival in Pediatric In-Hospital Cardiac Arrest

  JAMA Network Open · 2025-11-20 · 3 citations

  articleOpen access1st authorCorresponding

  Importance: The optimal airway management during pediatric in-hospital cardiac arrest (IHCA) is unknown. Objective: To evaluate intubation trends during pediatric IHCA between 2000 and 2022, and determine the association of intra-arrest intubation with survival in a recent cohort of patients (2017-2022). Design, Setting, and Participants: This retrospective cohort study (analysis performed between June 2023 and October 2024) used data from the multicenter American Heart Association Get With The Guidelines-Resuscitation registry. Pediatric patients (<18 years) with IHCA from 2000 through 2022 were included. Exposure: Intra-arrest endotracheal intubation. Main Outcomes and Measures: The primary outcome was survival to hospital discharge. Intra-arrest intubation trends were assessed using nonparametric test for trend. A time-dependent propensity matched analysis assessed the association between intra-arrest intubation and hospital survival from 2017 through 2022. Each minute, patients intubated were matched with patients at risk of intubation using a propensity score, with forced matching on stratification variables and replacement of controls. Mixed-effects logistic regression assessed the association with survival outcomes, with subgroup analysis by age and illness category. Results: The cohort included 3262 pediatric patients with IHCA (median age, 12.0 [IQR, 3.0-83.8] months; 1775 [54.4%] male) with no advanced airway at CPR onset. Return of spontaneous circulation was attained in 2413 patients (74.0%), and 1748 (53.6%) survived to hospital discharge. The intubation rate decreased over time (33 of 39 [84.6%] in 2000 to 112 of 168 [66.7%] in 2022; P < .001). In the 2017-2022 cohort, intubation vs nonintubation in each minute of CPR was associated with decreased discharge survival odds in unadjusted analysis (odds ratio [OR], 0.18; 95% CI, 0.14-0.24; P < .001) but not after matching (adjusted OR, 1.18; 95% CI, 0.90-1.53; P = .23). In children aged 8 years or older, after matching, intubation compared with nonintubation in each minute was associated with increased odds of discharge survival (adjusted OR, 1.91; 95% CI, 1.09-3.33; P = .02). Conclusions and Relevance: In this cohort study of pediatric patients with IHCA between 2017 and 2022 without an advanced airway at the start of CPR, no association was identified between intra-arrest tracheal intubation and hospital survival after time-dependent propensity score matching. In subgroup analysis, intra-arrest intubation in children 8 years or older was associated with higher survival odds. These findings may have important clinical implications for clinicians caring for children with IHCA and warrant further investigation into the physiologic and practical mechanisms of this association.

  PublisherOA PDFDOI

• 852: SHOULD WE HOLD OUR BREATH? APNEIC TIME DURING PEDIATRIC INTUBATION

  Critical Care Medicine · 2025-01-01

  article
  PublisherDOI

• Abstract Or116: Association of Ventilation Rate with Outcomes of Pediatric Cardiac Arrest

  Circulation · 2025-11-03 · 1 citations

  article1st authorCorresponding

  Background: The optimal ventilation rate during pediatric in-hospital cardiac arrest is not known. Research Question/Hypothesis: Is guideline-compliant ventilation during cardiopulmonary resuscitation (CPR) associated with improved survival? We hypothesized that CPR events with guideline-compliant average ventilation rates would have increased rates of survival to hospital discharge. Aims: The overall objective of this study was to assess the association between pediatric CPR ventilation rates and survival outcomes. Methods/Approach: Multicenter prospective observational cohort ancillary study of the ICU-RESUS trial (NCT02837497). Hospitalized children (≤18 years) with cardiac arrest and an endotracheal tube at the onset of CPR and evaluable intra-arrest end tidal carbon dioxide (ETCO2) data to calculate ventilation rate were included. The association between the existing AHA CPR ventilation rate target (20-30 breaths per minute [bpm]) and survival to hospital discharge was evaluated with Poisson regression using generalized estimating equations, controlling for a priori covariates (initial rhythm, immediate cause of arrest). In an exploratory analysis, natural cubic splines, controlling for the same a priori covariates, stratified by age (&lt;8 and ≥8 years), were used to identify novel target intra-arrest ventilation rates for subsequent evaluation in multivariable models. Results: Among 234 included events, 36.8% (n=86) had guideline-compliant average ventilation rates (20-30 bpm). After adjusting for confounders, there was no association between guideline-complaint ventilation rates and survival to hospital discharge (aRR 0.95, 95% CI: 0.75, 1.21, p=0.68). Our exploratory analysis identified novel age-based potential thresholds (&lt;8 years: ≥26 bpm; ≥8 years: &lt;26 bpm) (Figure 1). In children &lt;8 years, an event-level average CPR ventilation rate of ≥26 bpm, compared to &lt;26 bpm, was associated with increased survival to hospital discharge (aRR 1.32, 95% CI: 1.00, 1.73, p=0.048). Conclusions: In our multicenter study of intra-arrest ventilation in children with IHCA with an invasive airway in place at the start of CPR, we did not find an association between guideline-compliant average ventilation rate and survival. In children &lt;8 years old we identified a target ventilation threshold of ≥26 breaths per minute, which was associated with improved survival to hospital discharge.

  PublisherDOI

• Abstract Sat708: Pediatric Airway Opening Index: Novel Description and Association with Cardiac Arrest Physiology and Outcomes

  Circulation · 2025-11-03 · 2 citations

  article

  Introduction: Pediatric cardiopulmonary resuscitation (CPR) guidelines provide primitive ventilation guidance (observe chest rise, target a ventilation rate). Calculated from capnography waveforms, airway opening index (AOI) is a metric recently described in adults to infer airway patency during CPR. AOI has not yet been associated with survival nor described in pediatric patients. Aims: 1) To quantitatively describe AOI during pediatric CPR and 2) to evaluate the association of AOI with intra-/post-arrest physiology and outcomes. Methods: This was a prospective multicenter observational cohort study. Children (≤18 years) with invasive airways and end-tidal carbon dioxide (ETCO 2 ) / arterial blood pressure (BP) data were included. AOI was calculated as the average of ((delta CO 2 )/max CO 2 ) associated with each chest compression during a ventilation (range 0 [closed] to 1 [open/patent]). Cubic splines / receiver operating characteristic curves were used to identify an AOI target for evaluation in modified Poisson regression models ( a priori covariates: age; cause of arrest; P ediatric RIS k of M ortality score). A sensitivity analysis excluded extracorporeal CPR patients (E-CPR). The primary outcome was survival to hospital discharge (SHD). Secondary / exploratory outcomes included: other patient outcomes (e.g., favorable neurological outcome [Pediatric Cerebral Performance Category Score 1-3 or no change]) and intra- and post-arrest (6 hours after return of circulation [ROC]) physiology. Results: Among 99 included events (median age: 0.34 [0.04, 3.26] yrs), median AOI was 0.38 (survivors: 0.45 [0.28, 0.61]; non-survivors: 0.30 [0.24, 0.48]; p=0.02). A target AOI of ≥0.35 was identified, which was associated with improved SHD (aRR 1.53 [CI95 1.03, 2.28], p=0.04) and favorable neurological outcome (aRR 1.56 [CI95 1.01, 2.41], p=0.04) compared to an AOI &lt;0.35. During CPR, intra-arrest ETCO 2 was lower (-5.82 mmHg [CI95 -9.72, -1.91], p&lt;0.01) in events with AOI ≥0.35. Findings were robust when excluding E-CPR patients. In the 6 hours after ROC, events with AOI ≥0.35 had lower peak arterial lactates (6.1 [3.2, 13.1] vs. 11.4 [5.4, 16.1] mmol/L, p=0.043), despite similar CPR durations (≥0.35: 9 [3, 36] vs. &lt;0.35: 8.5 [3, 21] min, p=0.64). Conclusions: In this multicenter study, an AOI ≥0.35 was associated with improved survival and favorable neurological outcome. Among events with AOI ≥0.35, there was evidence of improved immediate post-arrest physiology (lower lactates).

  PublisherDOI

• 47: DEVELOPMENT OF A NOVEL CARDIAC ARREST VENTILATION RATE METRONOME: A HUMAN FACTORS APPROACH

  Critical Care Medicine · 2025-01-01

  article
  PublisherDOI

• The Latest in Resuscitation Research: Highlights From the 2024 American Heart Association's Resuscitation Science Symposium

  Journal of the American Heart Association · 2025-09-19

  articleOpen access
  PublisherDOI

• Prearrest vital sign abnormalities are associated with adverse outcomes in pediatric ICU cardiac arrest: a get with the guidelines-resuscitation analysis

  Resuscitation · 2025-09-25

  articleOpen access

  AIM: We aimed to quantitatively describe vital sign abnormalities prior to pediatric IHCA and evaluate whether the severity of abnormalities was independently associated with survival. METHODS: In a retrospective cohort study using the American Heart Association's Get with The Guidelines-Resuscitation® registry, children with ≥1 min of cardiopulmonary resuscitation (CPR) in an Intensive Care Unit (ICU) from 2007 to 2022 with prearrest vital signs were included. Vital signs most proximate to CPR (10-120 min prior) were classified as abnormal (HR or RR >95th, SBP or DBP <5th percentile for age). Multivariable regression adjusted for age, illness category, prearrest conditions, and prearrest interventions assessed the associations between vital sign abnormalities and outcomes (primary: survival to hospital discharge, secondary: return of spontaneous circulation [ROSC]). RESULTS: Of 2875 IHCA patients meeting inclusion criteria, 1790 (62.3 %) had at least one abnormal vital sign. Patients with vital sign abnormalities were older, had non-surgical illness categories, and higher prevalence of prearrest illnesses and interventions. Low SBP (<5%) was the vital sign with the lowest odds of survival to hospital discharge (aOR 0.56 [95 %CI 0.46-0.68], p < 0.01) and ROSC (aOR 0.63 [95 %CI 0.54-0.73], p < 0.01). There was a stepwise decrease in the adjusted odds of survival for each additional abnormal vital sign (1 vs 0: aOR 0.62 [95 %CI 0.51-0.76], p < 0.01; 2 vs 1: 0.72 [95 %CI 0.53-0.97] p = 0.03; 3 vs 2: 0.53 [95 %CI 0.33-0.86] p < 0.01). CONCLUSIONS: Prearrest vital sign abnormalities are common in pediatric ICU IHCA and independently associated with worse outcomes, emphasizing the need for prompt detection and intervention to improve outcomes.

  PublisherDOI

• Physiology-Guided CPR

  Critical Care Clinics · 2025-09-14

  article1st authorCorresponding
  PublisherDOI

• Development of a Novel Cardiac Arrest Ventilation Rate Metronome: A Human Factors and Implementation Science Mixed-Methods Approach

  Pediatric Critical Care Medicine · 2025-08-15

  articleOpen access

  OBJECTIVES: Excessive ventilation adversely affects cardiopulmonary resuscitation (CPR) hemodynamics and outcomes. Pediatric providers rarely achieve guideline-recommended CPR ventilation rates. We aimed to use human factors engineering to design a metronome to improve compliance with recommended CPR ventilation rates. We hypothesized that in usability testing, our novel metronome would achieve: 1) a System Usability Scale (SUS) score greater than 68 and 2) greater than 70% of CPR epochs with ventilation rates within target range, which would be sufficient to support a pilot trial in our PICU. DESIGN: Prospective single-center mixed-methods study. SETTING: Seventy-five-bed academic PICU. PARTICIPANTS: Multidisciplinary clinicians. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We elicited clinician feedback on the proposed ventilation rate metronome with a survey. Participatory design sessions determined optimal metronome components. During high-fidelity simulation usability testing, we collected qualitative and quantitative measures reflecting participant feedback and performance. Average ventilation rates were calculated during 30-second epochs of CPR, with average rates ± 2 breaths/min (bpm) from the target considered to be within goal range. Among 107 survey respondents, perceptions of appropriateness, acceptability, and feasibility of the ventilation rate metronome were favorable. The final prototype used a bell sound for high saliency in noisy environments and a scrolling timed vertical bar, with pre-set options for three guideline-recommended CPR ventilation rates (infants: 30 bpm, children 1-17 yr old: 20 bpm, adults: 10 bpm). In usability testing (three groups, 34 clinicians), median SUS was 92.5 of 100 (interquartile range, 89.4-93.1), with 0 attributable errors. Overall, 34 of 36 (94% [95% CI, 81-99%]) epochs of simulated CPR with metronome use had ventilation rates ± 2 bpm from the target rate. CONCLUSIONS: Utilizing human factors engineering and implementation science, we successfully designed a novel ventilation rate metronome. When deployed during high-fidelity cardiac arrest simulations, metronome use had high usability scores and resulted in excellent compliance with recommended ventilation rates.

  PublisherOA PDFDOI

Frequent coauthors

• David Kessler

  Columbia University

  41 shared

• Aaron W. Calhoun

  University of Louisville

  37 shared

• Lindsey Justice

  Cincinnati Children's Hospital Medical Center

  36 shared

• Amy R. Florez

  Cincinnati Children's Hospital Medical Center

  36 shared

• Benjamin T. Kerrey

  University of Cincinnati

  36 shared

• Gregory E. Gilbert

  36 shared

• Mary E. Frey

  Cincinnati Children's Hospital Medical Center

  36 shared

• Sara E. Constand

  Robert Wood Johnson Foundation

  36 shared

Education

• MSCE

  University of Pennsylvania

  2024

• MD

  Thomas Jefferson University

  2017

• BA

  University of Pennsylvania

  2012