Technology and the Delivery Room Jeffrey M Perlman Professor of Pediatrics Weill Cornell Medical College, New York Presbyterian Hospital New York, NY Faculty Disclosure Information In the past 12 months, I have had the following financial relationship Travel Grant from Laerdal Global Health to Oversee the HBB Program Development in Tanzania I do not intent to discuss an unapproved/investigative use of a commercial product/device in my presentation. Session Title NRP Current Issues Seminar Session Number Faculty Name, Jeffrey Perlman MB Ch B, FAAP Faculty Institution Weill Cornell Medical College, New York Presbyterian Hospital, New York City, NY Outline • Basic Principals of Cardio-Pulmonary Adaptation at delivery • Assessing the Effectiveness of Resuscitation/Ventilation • Determination of Heart Rate • Can Technology Facilitate Resuscitation - Detection of mask leak - Detection of Tidal volume - Detection of End Tidal CO2 Background • The birth of the infant is associated with cessation of the feto-placental circulation with subsequent profound physiological changes that involve both the cardiac and respiratory systems. • Helping the newly born infant successfully make this transition is the ultimate challenge • The management of the depressed infant in the first minutes of life can directly affect the quality of an individuals life with long lasting consequences. Requirement for Delivery Room Interventions • > 95% of term infants will respond to the basic steps in resuscitation including drying, position, suction • Approximately 1 to 3 % will require BMV • < 1 % will require Intubation • 0.12% will require Intensive Resuscitation • Intensive resuscitation may occur in the presence or absence of severe fetal acidemia (cord pH < 7.00) Conceptual Approach to an Infant as a Function of the Heart Rate During the Initial Golden Minute Following Birth Golden Minute Crying HR Rate > 140BPM Apgar > 7 Breathing HR ± 120BPM Apgar 5 to 7 HR 0 to 60 Apneic Apgar 0 to 1 HR 60 to 100 BPM ± Respirations Apgar 2 - 4 Four Basic Concepts • Is the Baby in Primary or Secondary Apnea ? • Effective Ventilation is key to successful Resuscitation • Establishing Functional Residual Capacity • Establishing ROSC Primary vs Secondary Apnea Adapted from Dawes et al 1968 Resuscitation in the Delivery Room PMH experience Sept 91-Sept 93 Live Births n = 30898 Chest Compressions/ Epinephrine n = 39 (0.12%) Term n=15 Preterm n=24 Asphyxia n=10 Improper ETT Placement n=5 Ineffective / Improper Ventilator support n=24 From Perlman & Risser Arch Pediatr Adolesc Med 149:20;1995 Fundamental Point Rapid Increase in Heart Rate is the best indicator of Effective Ventilation Determination of Heart Rate Clinical Assessment of Heart Rate - Comparison of the HR as Determined by Femoral, Brachial and Cord pulse palpation • All cases of healthy newborns (n=60), auscultation of HR was >100 bpm. • 55% of Cord Palpation identified HR > 100 BPM • 25% of Brachial and Femoral palpation identified HR > 100 BPM Owen CJ , Wyllie JP Resuscitation 50, 213: 2004 Role of Pulse Oximetry (PO) in Determination of HR • Study Population: 55 infants of BW of 2399g and GA 35 weeks • Median time taken to acquire HRPO was 68 sec (60 to 118 sec) • Time to acquire HRECG was 80 sec (64 to 104 sec) • There were 42 data points from 10 infants in which HR PO was < 100 bpm when HRECG was > 100 bpm. • Recommendation Use PO as an adjunct to careful clinical surveillance of infant HR, especially for very preterm infants who may need resuscitation. Kamlin et al J Pediatr 152; 756-760:2008 ILCOR Treatment Recommendation (2010) Assessment of Cardio-Respiratory Transition • Heart rate should remain the primary vital sign by which to judge the need for and efficacy of resuscitation. • Auscultation of the precordium should remain the primary means of assessing heart rate. • There is a high likelihood of underestimating heart rate with palpation of the umbilical pulse, but this is preferable to other palpation locations. • For babies who require ongoing resuscitation or respiratory support or both, the goal should be to use pulse oximetry. Because of concerns about the ability to consistently obtain accurate measurements, pulse oximetry should be used in conjunction with and should not replace clinical assessment of heart rate during newborn resuscitation. ILCOR Treatment Recommendations Circulation. 2010;122:S516-S538 New Data Since 2010 EKG shows Reliable Heart Rate Much Earlier than PO during Neonatal Resuscitation • Study Population: 20 infants of BW 2338 g and GA 36 weeks • The median time (IQR) taken to acquire reliable HR with ECG was 38 s (34–43) • The time to acquire stable PR values with PO was 122 s (101–146) P < 0.001) Time Muzimoto, et al. Pediatrics International (2012) 54, 205–207 Electrocardiogram Provides a Continuous Heart Rate Faster Than Pulse Oximetry During Neonatal Resuscitation • Study Population 30 infants (23–30 weeks) had simultaneous ECG and PO data. • The median total time to place EKG vs PO was (26 vs 38 sec; P = .04), • Time to achieve an audible HR signal after ECG vs PO was 2 vs 24 sec (p < 0.001) • During initial resuscitation, 93% of infants had ECG HR vs 56% for PO. Representative Tracing Katheria A, et al. Pediatrics 2012;130:e1177-e1181 Use of EKG Clip to Detect HR in Healthy Term Newborns Average heart rate [bpm] with 95% confidence interval 180 170 160 150 140 130 120 110 100 0 50 Linde et al Ped Res 2014 100 150 Time [s] 200 250 300 Summary • The optimal method to assess/detect HR will depend on the initial rate. • A low or absent HR – either EKG, ETCO2 or auscultation • A HR 60 to 100 – auscultation ± PO ± ETCO2 • A HR > 100 – auscultation ± PO Assessment of Effective Ventilation Understanding the Pathophysiology Establishing Functional Residual Capacity (FRC) Lung Volumes Physiologic Pulmonary Measurements of Spontaneously Breathing Infants at Birth Following Vaginal Delivery • Mean inspiratory pressure = 52 cm H2O (range 25-105) • Mean Inspiratory Volume = 37 ml (range 10-80) • Functional Residual Capacity = 15 ml (range 8-30) Following Cesarean Section • Similar Inspiratory pressures and volumes • Only 50% establish a FRC with the first breath From Vyas, et al. Pediatr Pulm 787, 1981 Initial Expiratory Effort and Establishing FRC Initial Expiratory Effort and Establishing FRC Mechanisms Contributing to a Variable Response to Either Spontaneous Breathing and/or PPV The inconsistent response to PPV in some infants in part reflects the infants response to initial mechanical breaths • The most common is a REJECTION response with the production of high intrathoracic pressure, i.e. expiratory effort with no gas exchange. • A second response is the called “HEADS” paradoxical reflex with production of high negative intra-esophageal pressure and a marked improvement in the mechanical characteristics of the lung and the establishment of a functional residual capacity. • The third response is PASSIVE inflation with no change in esophageal pressure. “HEADS” Paradoxical Response Rejection Response Passive Inflation From Boon, et al. Arch Dis Childh 1979, 492 Establishing FRC in Apneic Babies • Prolonging Inspiratory time • Role of PEEP Pressure and Volume Characteristics in Infants requiring Resuscitation with Varying Inspiratory Times Measurement Mean Volume Change (ml) Functional Residual Capacity (ml) Inspiratory Time 1 Second 3 Seconds 15.3 33.5 1.0 15.9 Changes in Lung Gas Volume From Birth in Anesthetized Ventilated Preterm Rabbit Pups Using Plethysmography SI(20s) + PEEP FRC PPV + PEEP PPV No PEEP SI(20s) No PEEP Te Pas, et al. Pediatric Research 2009;65:537 Summary • Establishing FRC in a non breathing baby maybe extremely difficult because of several competing factors. • Appropriate application of a face mask maybe difficult with leak a common problem. • Inadvertent upper airway obstruction may complicate ventilation. • Assessment of chest rise is a poor indicator of delivered TV. • Clinically the MRSOPA pneumonic is used as a tool to achieve effective ventilation. • A Respiratory Function Monitor that provides objective evidence for Leak, ETCO2 measures and/or expired Tidal volume may facilitate effective ventilation. Respiratory Function Monitor Assessment of Chest rise during Mask Ventilation of Preterm Infants in the DR- Clinical Assessment vs a Respiratory Function Monitor (RFM) • Airway pressures and expiratory tidal volume (VTe) were measured during neonatal resuscitation using a RFM. • After 60 s of PPV, resuscitators standing at the infants’ head (head view) and at the side (side view) were asked to assess chest rise and estimate VTe. • 30% of observers felt unable to assess chest rise from the head and 15% from the side. • Observers tended to underestimate TV by 3.5mL (Head) and 3.3mL (Side) • Agreement between clinical assessment and measured VTe was poor. Poulton D, et al. Resuscitation, Volume 82, Issue 2, 2011, 175 - 179 Assessment of Chest rise during Mask Ventilation of Preterm Infants in the DR- Clinical Assessment vs a Respiratory Function Monitor (RFM) Expired tidal volume ( V Te ) for the 20 individual infants. Horizontal lines show the range of VTe which would provide reasonable ventilation. The Box plots show median (solid bar), IQR (margins of the box) and 95% confidence interval. Poulton D. et al, Resuscitation, Volume 82, Issue 2, 2011, 175 - 179 Respiratory Function Monitor (RFM) Guidance of Mask Ventilation in the DR: A Feasibility Study Infants receiving mask resuscitation were randomized to have the RFM Display Visible (airway pressure, flow, and VT waves) or masked. Repositioning was done in 19 (73%) vs 6 (26%) of RFM visible vs Masked group (P= .001). Schmölzer et al J of Pediatrics, Volume 160, Issue 3, 2012, 377 - 381.e2 Mask Respiratory Support in the First 5 Minutes in the DR Role of a Respiratory Function Monitor • PPV was delivered with a round silicone facemask connected to a T-piece device and RPM which was not visible to the provider. • Substantial leak was observed during all four breath types median leaks range - 24% to 59%. • Median TV were greater during inflations (8.3 ml/kg) and assisted inflations (9.3 ml/kg) than spontaneous breaths between PPV (3.2 ml/kg) and breaths during CPAP (3.3 ml/kg). Kaufman J, et al. Arch Dis Child Fetal Neonatal Ed 2013;98:F405-F410 Role of End Tidal CO2 Monitoring End-tidal CO2 Detection of an Audible Heart Rate During Neonatal Cardiopulmonary Resuscitation Following Asystole in Asphyxiated Piglets • • • Representative tracing of ETCO2 and mean arterial pressure (MAP) during CPR Chalak et al Pediatric Res 69;401-405: 2011 Study objective was to determine the threshold ETCO2 associated with ROSC following asphyxiainduced asystole in neonatal swine (n=46) progressively asphyxiated until asystole occurred. ETCO2 cut off value of 14 mmHg was the most sensitive ETCO2 value with the least false positives. When using ETCO2 to guide uninterrupted CPR in experimental asphyxia-induced asystole, auscultative confirmation of return of an adequate HR should be performed when ETCO2 ≥14 mmHg is achieved. Quantitative End-Tidal Carbon Dioxide Monitoring in the Delivery Room: A Randomized Controlled Trial • Prospective randomized controlled trial of infants who received PPV • (PPV) to a control versus a monitored arm with a goal to investigate the utility of continuous quantitative end-tidal CO2 (EtCO2) monitoring for managing assisted ventilation in the DR. Physiologic and intervention data from a representative subject (top tracing represents ventilating pressures; bottom tracing represents Et CO 2 levels, x axis represents seconds of life). Kong , et al Journal of Pediatrics, 163; 2013, 104 - 108. • The median EtCO2 levels at end of resuscitation were 44 mm Hg (16-66) in controls and 43 mm Hg (29-59) in the monitored arm • The proportion of admission PCO2 levels outside of the prespecified range was 33.3% (control) vs 37.5% (monitored) Positive Pressure Ventilation, Spontaneous Respiratory Effort and FRC in Premature Infants Role of RFM in Detection of TV and ETCO2 Role of PPV Pre, During and Post Infants Own Respiratory Effort Relationship of Expiratory Tidal Volume and ETCO2 Pre, During and Post Own Inspiratory Effort Murphy V. et al, Arch Dis Child Fetal Neonatal Ed 2012;97:F249-F253 Relationship of Expiratory Tidal Volume and ETCO2 Pre, During and Post Own Inspiratory Effort Pre- Active Inflation Active Inflation Post Inflation Expired tidal volume (ml/kg) 1.8 (0.7–7.3) 6.3 (1.9–18.4) 4.5 (0.5–18.3) ETCO2 (kPa) 0.3 (0.1–2.1) 3.4 (0.4–11.5) 2.2 (0.3–9.3) 20.0 (13.8–26.7) 19.6 (13.7–25.9) 20.2 (13.4–25.9) Inflation pressures (cm H2O) (Peak–PEEP) Murphy V et al Arch Dis Child Fetal Neonatal Ed 2012;97:F249-F253 Summary • Respiratory Function Monitor may play an important role in infants needing respiratory support in the DR. • RFM may facilitate effective ventilation by identifying mask leak and /or evidence of obstruction. • ETCO2 monitoring may facilitate detection of ROSC. • ETCO2 monitoring may provide evidence of establishment of FRC. • A dedicated individual and not the primary resuscitator should be the individual who monitors the RFM during a resuscitation Conclusions • Resuscitating a Newly Baby is a Dynamic process- one shoe does not fit all cases. • Establishing FRC in the apneic baby may require using PEEP or prolonging the IT or a combination of both. • A RFM maybe useful as an adjunct is some cases when it is unclear whether ventilation is effective.