Transcript Paediatric ICU: Acute Respiratory Distress

Paediatric ICU: Acute
Respiratory Distress
Aylin Seven
Upper –
croup/epiglottis
Lower – bronchiolitis
Lung –
pneumonia/ARDS,
pulmonary oedema
Neuromuscular
Chest wall trauma
Pleural effusion
Pneumothorax
CAUSES OF
RESPIRATORY
FAILURE
Status Epilepticus
Apnoea of
prematurity
Intoxication
Trauma
Cardiac
Metabolic
Hypovolaemia
Septic Shock
Why are kids so vulnerable?
• Metabolism
• Risk of
apnoea
• Upper airway
resistance
• Lower airway
resistance
• Efficiency of
muscles
• Endurance of
muscles (less
type 1)
• Lung volumes
Identifying the deteriorating
patient
• Respiratory rate
• Work of breathing
• Bradycardia = BAD
PAT
Normal Respiratory Rates
• 1 month to 1 year  24-38 breaths/min
• 1-3 y  22-30 breaths/min
• 4-6y  20-24breaths/min
• 7-9  18-22 breaths/min
What to do next?!
What are your options?
BMV
HFO
NIV
Intubation + Mechanical Ventilation
Positioning etc…
• Midline sniffing position
• Prominent occiput in
infants  towel roll under
the shoulders
• Suction (remember nasal
suctioning!)
• Nasal + oropharyngeal
airways
HFO
• Indications:
– Respiratory distress from bronchiolitis, pneumonia, heart failure
– Post extubation
– Weaning from mask CPAP/BiPAP
– Neuromuscular disease
– Apnoea of prematurity
• High flow can be used if there is hypoxaemia (SpO2<90%) and signs of
moderate to severe respiratory distress despite standard flow oxygen.
• Contraindications:
– Blocked nasal passages/choanal atresia
– Trauma/surgery to nasopharanyx
Mechanisms of Action
• Delivered at near body temp, up to 100% relative humidity
 delivering up to 8L/min in neonates without irritation
• Washout of inspiratory dead space  improves alveolar
ventilation
• HFNC may stent the upper airway  reduce upper airway
resistance
• Positive distending pressure (but signifcant affected by
flow rate, leakage, cannula size)
NIV
• Bubble CPAP
• (Others: BiPAP/CPAP)
Bubble CPAP
• Indications:
– Acute lower airway obstruction
– Dynamic upper airway obstruction
(laryngomalacia, tracheomalacia)
– Parenchymal lung disease (e.g. pneumonia)
– Ventilation weaning
Bubble CPAP
• Contraindications:
– Severe cardiovascular instability
– Poor respiratory drive (frequent apnoea/brady)
– Congenital malformations of airway
– NOTE: relative contraindication in >10-12kg
Bubble CPAP
• Mechanism:
– Expiratory arm is under water  generates
pressure and oscillations (almost similar to high
frequency 15-30Hz)
– Gentle bubbling = vigorous bubbling
– No bubbling = loss of seal (often open mouth)
For example, if the gas flow is set at 6 L/min and the CPAP probe is set at 6 cmH 20, mean
CPAP generated at the interface with a good seal will be 6.4 cmH20.
Mean CPAP values generated by F-P Bubble CPAP at the set gas flow and Probe level using
F-P interface with a tight seal (source: F&P CPAP Manual)
Flow
L/min
4
5
6
7
8
9
10
11
12
13
14
15
Probe setting (cmH2O)
3
3.1
3.2
3.4
3.6
3.8
4
4.3
4.6
4.9
5.2
5.5
5.8
4
4.1
4.2
4.4
4.6
4.8
5
5.3
5.6
5.8
6.1
6.4
6.7
5
5.1
5.3
5.4
5.6
5.8
6
6.2
6.5
6.8
7
7.3
7.5
6
6.1
6.3
6.4
6.6
6.8
7
7.2
7.4
7.7
7.9
8.2
8.4
7
7.1
7.3
7.4
7.6
7.8
7.9
8.1
8.4
8.5
8.8
9
9.2
INFANT FLOW DRIVER (VIASYS SIPAP DRIVER)
8
8.1
8.3
8.4
8.5
8.7
8.9
9
9.2
9.4
9.6
9.8
10
9
9.1
9.2
9.3
9.5
9.6
9.8
9.9
10.1
10.2
10.4
10.6
10.8
10
10
10.1
10.2
10.4
10.5
10.6
10.8
10.9
11.1
11.3
11.4
11.6
Intubation
• Some important differences in intubating kids:
– Large tongue
– High, anterior airway
– Acute angle between tracheal opening and epiglottis
– Narrowest diameter is cricoid ring (adults = vocal cords)
– Laryngospasm (2 x more common in older children, and 3 x more
common in younger children)  light sedation, secretions,
extubation. Up to 96/1000 in URTI patients.
– Cuffed vs uncuffed and oral vs nasal
– ? Apnoeic oxygenation
Mechanical Ventilation
• Indications:
– Apnea
–
Respiratory failure not responsive to O2, HFNC, CPAP, or BiPap
–
Neurologic compromise
–
Impaired cardiovascular function
–
Post-Operative states with impaired ventilatory function
• Some considerations in paediatrics:
– Inspiratory time is usually 0.35-0.45s for full term babies  progressively increases to
1.0-1.4s by 8y
– No difference in outcomes (mortality and length of ventilation) based on variety of
modes including HFOV
Zebras and PICU
• Vascular rings/slings from aberrant
vessels (pulmonary artery sling –
anomalous L pulmonary artery and
ductus encircling trachea)
• Congenital diaphragmatic hernia
• Spinal muscular atrophy
• Diaphragmatic palsy (post CTx surgery)
• Tick bite paralysis (toxin binds
covalently to AchR)
• Tumours (neuroblastoma and
lymphoma)
Case 1
• 10 month old
• Admitted to ward with bronchiolitis D3
• Increased WOB on the ward  transferred to PICU
• Placed on WHO 2L/kg/min initially
• Ongoing significant work of breathing
• What next?
Case 1
• Bubble CPAP  no significant improvement
• For intubation  unsuccessful intubation
attempts x 3
• Eventual intubation with sevoflurane
induction
References
•
HNE – ICU guidelines for care of paediatric airway, paediatric bubble CPAP
•
Paediatric Airway Management, Santillanes and Gausche-Hill (2008)
•
Ventilatory strategies in the neonatal and paediatrc intensive care units, Mesiano
& Davis, Paediatric Respiratory Reviews (2008)
•
Oh’s Intensive Care Manual 2013
•
The evidence for high flow nasal cannula devices in infants, Haq et al, Paediatric
Respiratory Reviews (2014)
•
Acute respiratory failure in children, Hammer, Paediatric Respiratory Reviews
(2013)
Questions?