What is the role of MRSOPA (Medication, Respiratory, Surgical, Oxygen, Positioning, Assistance) in the resuscitation of a newborn infant with respiratory distress and bradycardia?

MRSOPA Framework in Neonatal Resuscitation

MRSOPA is a systematic mnemonic for correcting bradycardia and inadequate ventilation in newborns, applied sequentially when heart rate remains below 100 bpm despite initial positive pressure ventilation—each step must be optimized before progressing to chest compressions. 1

Understanding the MRSOPA Sequence

The MRSOPA acronym guides troubleshooting when a newborn fails to respond to initial ventilation attempts. The primary cause of neonatal bradycardia is inadequate lung inflation or profound hypoxemia, not primary cardiac pathology, making ventilation optimization the cornerstone of resuscitation. 1

M - Mask Adjustment (or Airway Repositioning)

• Ensure proper mask seal on the face, covering nose and mouth without compressing the eyes or overlapping the chin. 1
• Reposition the head to neutral "sniffing" position—avoid hyperextension or flexion which can obstruct the airway. 1
• Check for visible secretions obstructing the airway; suction only if secretions are present, as routine suctioning can cause vagal bradycardia. 2, 3

R - Reposition Airway

• Adjust head position to achieve optimal airway patency—the external auditory canal should align with the anterior shoulder. 1
• Consider placing a shoulder roll if the occiput is prominent, which is common in term newborns. 1
• Perform jaw thrust maneuver if airway obstruction persists despite repositioning. 1

S - Suction Mouth and Nose

• Suction the mouth first, then nose, only if secretions are visible or airway appears obstructed. 2
• Avoid deep or aggressive suctioning which triggers vagal bradycardia through laryngeal stimulation. 3
• Limit suctioning duration to prevent prolonged interruption of ventilation attempts. 1

O - Open Mouth (Ventilate with Mouth Slightly Open)

• Ensure the mouth is slightly open during bag-mask ventilation to prevent airway obstruction from the tongue falling back. 1
• This step is particularly critical in newborns with micrognathia or other craniofacial abnormalities. 1

P - Pressure Increase

• Increase peak inspiratory pressure if chest rise is inadequate—initial pressures of 20 cm H₂O may be effective, but 30-40 cm H₂O may be required in term infants without spontaneous ventilation. 1
• Monitor inflation pressure whenever possible; use the minimal pressure required to achieve visible chest rise and heart rate improvement. 1
• The primary measure of adequate ventilation is prompt improvement in heart rate, not just chest wall movement. 1

A - Airway Alternative (Consider Endotracheal Intubation or Laryngeal Mask)

• If heart rate remains below 60 bpm despite optimized bag-mask ventilation through all MRSOPA steps, proceed to endotracheal intubation to ensure effective ventilation before initiating chest compressions. 1
• Confirm endotracheal tube placement with exhaled CO₂ detection, which is the recommended method in infants with adequate cardiac output. 1
• Consider laryngeal mask airway as an alternative if intubation attempts are unsuccessful and gestational age is ≥34 weeks or birth weight >2000g. 1

Oxygen Titration During MRSOPA

• Begin resuscitation with 21% oxygen (room air) for term infants ≥35 weeks' gestation. 1
• For preterm infants <35 weeks' gestation, start with 21-30% oxygen. 1
• If heart rate remains below 60 bpm after 90 seconds of optimized ventilation, increase oxygen concentration to 100%. 1
• Titrate oxygen using pulse oximetry applied to the right hand (preductal) to target interquartile ranges: 70-80% in first few minutes, gradually rising to >90% by 10 minutes. 2

Critical Decision Point: When to Progress Beyond MRSOPA

If heart rate remains below 60 bpm despite adequate ventilation (preferably through endotracheal tube) with 100% oxygen after completing all MRSOPA steps, immediately initiate chest compressions using the two-thumb encircling hands technique with 3:1 compression-to-ventilation ratio. 1

Chest Compression Technique

• Compress the lower third of the sternum to approximately one-third of the anterior-posterior diameter of the chest. 1
• Deliver 90 compressions and 30 breaths to achieve approximately 120 events per minute. 1
• Coordinate compressions and ventilations to avoid simultaneous delivery, with exhalation occurring during the first compression after each ventilation. 1

Medication Administration After Failed MRSOPA + Compressions

If heart rate remains below 60 bpm despite adequate ventilation with 100% oxygen and chest compressions, administer epinephrine 0.01-0.03 mg/kg of 1:10,000 solution intravenously (preferred route). 1

• The intravenous route via umbilical venous catheter is preferable to endotracheal administration. 1
• If endotracheal administration is attempted while IV access is being established, higher dosing at 0.05-0.1 mg/kg may be reasonable, though efficacy is questionable. 1

Common Pitfalls to Avoid

• Do not proceed to chest compressions without first ensuring optimal ventilation through systematic MRSOPA troubleshooting—most neonatal bradycardia resolves with effective ventilation alone. 1
• Do not use 100% oxygen as initial resuscitation gas; this increases mortality compared to room air in term infants. 1
• Avoid excessive ventilation pressures that can cause pneumothorax, but ensure adequate pressure to achieve chest rise and heart rate response. 1
• Do not rely on clinical assessment of skin color (cyanosis) to determine oxygenation status—pulse oximetry is essential. 2