WCS19 Perinatal Medicine, Antenatal Care And Pre-pregnant Counselling 2 Flashcards
Newborn breathing
- ~10% newborn require assistance to begin breathing at birth
- 1% require extensive resuscitative measures
- earlier start of CPR —> better outcome
- longer the delay of CPR —> more time needed to be revived
Cessation of respiratory efforts is 1st sign that newborn is deprived of O2 (Hypoxic insult)
***Hypoxic insult in baby
Hypoxic insult —> Rapid breathing (Regular) —> Primary apnea —> Irregular gasping —> Secondary apnea
Primary apnea:
- HR ↓
- **BP maintain
- **Responsive to tactile stimulation
Secondary apnea:
- HR ↓
- **BP ↓
- **Requires PPV (positive pressure ventilation)
Neonatal Resuscitation Program: Key behavioural skills
- Know your environment
- Use available information
- Anticipate and plan
- Clearly identify a team leader
- Communicate effectively
- Delegate workload optimally
- Allocate attention wisely
- Use available resources
- Call for additional help when needed
- Maintain professional behaviour
Anticipation of Resuscitation need
Antepartum risk factors
- Gestational age <36 weeks
- Gestational age >=41 weeks
- Pre-eclampsia / Eclampsia
Etc.
Intrapartum risk factors
- Emergency C section
- Forceps / Vacuum assisted delivery
- Breech / Abnormal presentation
***Process of resuscitation
- Warm
- towels / blankets - Clear airway
- meconium aspirator
- suction catheter - Auscultation
- Ventilate
- flowmeter
- PPV device - Oxygenate
- device to give free-flow O2
- pulse oximeter - Intubate
- laryngoscope - Medicate
- 1:10000 adrenaline
- normal saline
Targeted preductal (right arm) SpO2 after birth
1 min: 60-65%
2 min: 65-70%
3 min: 70-75%
4 min: 75-80%
5 min: 80-85%
10 min: 85-95%
Initial evaluation to determine if resuscitation is required
4 questions:
1. Expected gestational age?
2. Amniotic fluid clear?
3. How many babies?
4. Additional risk factors?
Every birth should be attended by >=1 qualified individual, skilled in initial steps of newborn care and PPV, only responsibility is management of newborn
***Questions after delivery:
1. Does baby appear to be term?
2. Does baby have good muscle tone?
3. Is baby breathing / crying?
ALL Yes:
- Routine care, dry, warm, position airway, clear secretions if needed
- Delay umbilical cord clamping for >= 30-60 secs for vigorous (i.e. normal) newborns not requiring resuscitation
—> more blood return to baby —> more haemodynamically stable, prevent anaemia
ALL No:
- Start initial evaluation (***Initial steps of newborn care)
- Stimulate, dry, warm, position airway, clear secretions if needed
- No definitive recommendation of cord clamping
Initial steps of newborn care (Resuscitation)
- Provide warmth
- Position head and neck in neutral / “sniffing” position (slightly ***extended neck)
- ***Remove airway secretions with
- Bulb syringe / Suction catheter (80-100 mmHg)
- Suction Mouth —> Nose (avoid aspiration)
- Avoid deep and vigorous suction —> Tissue injury + Vagal stimulation (prolonged bradycardia) - Dry
- Stimulate, Reposition the head to open airway
- gently rub back, trunk, extremities
- slap / flick sole
- do NOT perform one after the other
- ***several seconds only
- gasping should be treated as apnea
***PPV
Indications:
1. Apnea / Gasping
2. HR < 100 (HR in 6 secs x 10)
3. SpO2 below target range despite free-flow O2 / CPAP (Continuous positive airway pressure)
Prepare:
1. PPV
- lung ventilation the single ***most effective step in newborn CPR
- SpO2 monitor
- pulse oximeter (**R hand / wrist)
- resuscitation is anticipated
- confirm your perception of persistent central cyanosis
- supplementary O2 administered to achieve target values according to oxygen saturation table (term + preterm), avoid SpO2 >95%
—> **avoid giving too much O2 to avoid free radical problems
- PPV is required - ECG monitor
Evaluation:
- HR
- RR
During PPV:
1. Initial O2 conc
- 21% for newborns >= 35 weeks
- 21-30% for preterm newborn < 35 weeks
- Ventilation rate: 40-60 breaths per min
- Initial ventilation pressure: 20-25 cmH2O
- ***Rising HR: most important indicator of successful PPV
- Check HR after first 15 seconds of PPV
- HR not ↑ —> check chest movement —> no chest movement —> ventilation corrective steps (***MR. SOPA) - Check HR again after 30 seconds of PPV that inflates the lung
- HR > 100 —> gradually ↓ rate + pressure —> discontinue
- 60 < HR < 100
—> reassess ventilation technique
—> perform corrective steps
—> adjust O2 conc as indicated by pulse oximetry
—> insert ***alternative airway if not already done - HR < 60
—> alternative airway is strongly recommended
—> call for additional help
—> ↑ O2 conc to 100% and begin ***chest compression
- Insert ***Orogastric tube if CPAP / PPV with mask > several minutes
- avoid distension of stomach —> aspiration + hinder chest expansion - If a step is not delivered effectively, may need >= 30 seconds to correct to problem
***MR. SOPA
Do in pairs
M: Mask adjustment
R: Reposition the head
S: Suction mouth and nose
O: Open mouth
P: Pressure increase (5-10 cmH2O increment) to Max 40 cmH2O
A: Alternate airway (ET intubation / Laryngeal mask airway)
Laboured breathing, Persistent cyanosis (but NO apnea, gasping, HR below 100bpm)
- Position and clear airway
- SpO2 monitor
- Supplemental O2 as needed
- Consider CPAP
Meconium stained fluid
If baby is vigorous
- Suction mouth and nose with Bulb synringe
- Baby can remain with mother for initial steps
If baby not vigorous
- Possibility of meconium aspiration
- Bring baby to radiant warmer to perform initial steps
- Routine intubation for tracheal suction is ***NOT suggested (only when baby cannot revive by MR. SOPA)
—> Thick meconium in airway —> Pressure increase + Alternate airway
—> Use Meconium aspirator connected to suction catheter after intubation
Chest compression
Indications:
***HR <60 despite >= 30 sec of PPV that inflate the lung
- pulse oximeter may stop working
- continue ventilation with 100% O2 until HR >=60 and pulse oximeter has reliable reading
Thumb technique:
- encircling torso with both hands
- thumbs placed on sternum (side by side / one over another on small baby)
- fingers under the back to support spine
- thumb flexed at at first joint (手指尖)
- depress sternum ~1/3 of AP diameter
- pressure must remain on sternum and apply vertically
Coordination with ventilation:
- One cycle of **3 compressions + 1 breath (4 events) takes **2 seconds
- ~ ***120 events per minute (30 breaths + 90 compressions)
- 1, 2, 3 —> bag —> 1, 2, 3 —> bag
After 60 seconds of chest compression and PPV
—> evaluate HR again
1. HR >=60, discontinue compression and resume PPV at 40-60 breaths per min
2. HR <60
- check quality of ventilation and compression
- give **Epinephrine IV through umbilical catheter / intraosseous route
- consider **hypovolaemia / pneumothorax
***ECG is preferred method for assessing HR during chest compression
Indications for endotracheal intubation
When ***chest compressions are necessary
Special use:
1. Stabilisation of newborn with suspected **diaphragmatic hernia (唔想bag d氣入stomach)
2. **Surfactant administration
3. Direct tracheal suction if airway is ***obstructed by thick secretions
If intubation is not successful / feasible —> Laryngeal mask
Signs of correct Endotracheal intubation
- ***Rapidly ↑ HR
- Presence of ***exhaled CO2 by CO2 detector
- Colorimetric devices (purple —> yellow in CO2 presence)
- Capnographs (waveform showing good oscillation with each breath) - Audible and Equal ***breath sounds near both axilla (lateral and high on chest wall) during PPV
- also listen to epigastrium (should have minimum breath sound) - ***Symmetrical chest movement with each breath
- Little / No air leak from the mouth during PPV
- Decreased / Absent air entry over stomach
If suspect tube not in trachea
- Reinsert laryngoscope to see if tube is between cords
- Remove tube, stabilise with mask ventilation, repeat intubation procedure
- Misplaced tube is worse than no tube
