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 NumberFaculty Name, Jeffrey Perlman MB Ch B, FAAPFaculty 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)

CryingHR Rate > 140BPMApgar > 7

BreathingHR ± 120BPMApgar 5 to 7

HR 0 to 60ApneicApgar 0 to 1

HR 60 to 100 BPM± RespirationsApgar 2 - 4

Gol

den

Min

ute

Conceptual Approach to an Infant as a Function of the Heart Rate During the Initial Golden Minute Following Birth

Four Basic Concepts

• Is the Baby in Primary or Secondary Apnea ?• Effective Ventilation is key to successful Resuscitation• Establishing Functional Residual Capacity• Establishing ROSC

Adapted from Dawes et al 1968

Primary vs Secondary Apnea

Resuscitation in the Delivery Room PMH experience Sept 91-Sept 93

Live Birthsn = 30898

Chest Compressions/ Epinephrinen = 39 (0.12%)

Term n=15 Preterm n=24

Asphyxia Improper ETT Ineffective / Improper Placement Ventilator support

n=10 n=5 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

Owen CJ , Wyllie JP Resuscitation 50, 213: 2004

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

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.

Katheria A, et al. Pediatrics 2012;130:e1177-e1181Representative Tracing

Use of EKG Clip to Detect HR in Healthy Term Newborns

0 50 100 150 200 250 300100

110

120

130

140

150

160

170

180

Time [s]

Aver

age

hear

t rat

e [b

pm] w

ith 9

5% c

onfid

ence

inte

rval

Linde et al Ped Res 2014

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 reflectsthe 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.

Rejection Response “HEADS” Paradoxical 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 Inspiratory Time

1 Second 3 Seconds

Mean Volume Change (ml) 15.3 33.5

Functional Residual Capacity (ml) 1.0 15.9

Te Pas, et al. Pediatric Research 2009;65:537

Changes in Lung Gas Volume From Birth in Anesthetized Ventilated Preterm Rabbit Pups Using Plethysmography

SI(20s) + PEEP

PPV + PEEP

SI(20s) No PEEP

PPV No PEEP

FRC

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.

Schmölzer et al J of Pediatrics, Volume 160, Issue 3, 2012, 377 - 381.e2

Repositioning was done in 19 (73%) vs 6 (26%) of RFM visible vs Masked group (P= .001).

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

• Study objective was to determine the threshold ETCO2 associated with ROSC following asphyxia-induced 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.Representative tracing of ETCO2 and mean arterial pressure (MAP) during CPR

Chalak et al Pediatric Res 69;401-405: 2011

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.

• 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)

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.

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

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)

Inflation pressures(cm H2O)(Peak–PEEP)

20.0(13.8–26.7)

19.6(13.7–25.9)

20.2(13.4–25.9)

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

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.