Download Paediatric Respiratory and OSA

PAEDIATRIC RESPIRATORY
AND OSA
Objectives
Recent RTi:
Proceed vs Postpone
Management of ‘Irritable Airways’
Asthma:
Management of Acute Severe Episodes
OSA:
Definitions and Risk Factors
Perioperative Anaesthetic Management
RHSC Guidelines for Postop Monitoring and Analgesia
RTi and Anaesthesia
URTi increases perioperative adverse events:
Coughing
Breath holding
Laryngospasm/bronchospasm
SaO2 <90% for >10 secs
Unanticipated intubation/reintubation
Atelectasis/pneumonia
Risk is greatest in presence of active infection but remains increased for 2-6
weeks post RTi. Airway reactivity remains increased for 6-8 weeks post RTi
Mild URTi
Clear runny nose, apyrexial, normal activity/appetite
Minimal concern and usually proceed as planned
Symptomatic RTi
Ideally Postpone
P u r u l e n t N a s a l D i s ch a r g e,
p r o d u c t ive c o u g h
C lin g y / ir r it ab le, le t h a r g ic,
p y r e x ial , r e d uc ed a c t ivit y a n d
a p p e t it e
Have to take into account:
Procedure (complexity, priority)
Ease of rearranging (staff, family)
What’s normal for individual child
Discuss with surgeon
Discuss with family: Risk vs Benefit of Proceed vs Postpone
Low threshold to postpone if:
1991
Age < 1 year
Major op/airway op
Asthma/atopy/other respiratory disease
ETT required
11x increased risk complication
Cohen et al Anesthesia &Analgesia
Anaesthesia for the
Irritable Airway
Preop:
Consider β2 agonist + Steroid inhalers
Combination 10-30 mins preop reduced bronchoconstriction and
perioperative respiratory events more than salbutamol alone
Silvanus et al Anesthesiolody 2004
Induction:
IV induction (propofol) less irritating than gas induction (sevo)
Limit airway stimulation/irritation ( Facemask /LMA rather than ETT)
Consider lubricating LMA with lignocaine gel
Schebesta et al Can J Anesthesia 2010
Anticholinergics theoretically should reduce bronchoconstriction
but studies showed glycopyrrolate to be no better than placebo
Tait et al Anesthesia & Analgesia 2007
Maintenance: TCI (propofol) = Volatile (sevo) so long as maintain adequate depth
Fentanyl / Remifentanil reduce airway irritability
Airway humidification
IV hydration
Removal of LMA/ETT : Awake vs Deep no difference in complications
Tait et al Anesthesia & Analgesia 2005
ASTHMA
Acute Severe Exacerbations
Airway inflammation
Excessive mucous production/plugging
Bronchospasm


Increased work of breathing
Increased intrathoracic pressure
Reduced airflow
Air trapping
Preload
Afterload
Catecholamine depletion
Respiratory insufficiency/failure
 insensible losses dehydration
Recognised Risk Factors
Previous sudden/rapid respiratory deterioration
Previous admission to PICU
Previous Ventilation
Syncope/seizures with asthma exacerbations
Poor adherence to recommended treatment
Poor control despite treatment/ oral steroids
Denial of severity/late presentation
Up to a third of children who die due to asthma were not previously identified
as at risk of fatal asthma!
Management
Pharmacotherapy: To ease work of breathing
To achieve adequate oxygenation and ventilation
Monitoring:
HR, RR, SaO2, conscious level/agitation, PEFR
accessory muscle use, wheeze
In HDU/PICU setting as prone to rapid deterioration
Clinical signs correlate poorly with severity of airway
obstruction
If possible endeavor to avoid intubation and ventilation
Scottish Paediatric Retrieval Guidelines
Step 1
(no more than 30 minutes)
Salbutamol:
(Grade 1A)
MDI Salbutamol 100microgram x 10 puffs via spacer
or
Salbutamol via Paediatric Nebuliser
< 4 years of age 2.5mg > 4 years of age 5mg
(should be diluted to 4mls with normal saline)
Oral Prednisolone:
< 1 year 2mg/kg
3-4 years 30mg
1-2 years
5+ years
20mg
40mg
High flow oxygen+SaO2 monitoring
If child requires nebulisers more frequently than half hourly then move to Step 2.
Step 2 (1 hour)
(Grade 1A)
Combined Salbutamol + Ipratropium nebulisers: x 3 over 1 hour
< 4 years of age: Salbutamol 2.5mg + Ipratropium 250microgram
> 4 years of age: Salbutamol 5mg + Ipratropium 500microgram
(diluted to 4mls with normal saline)
Apply Emla/Ametop cream in preparation for venous access.
Step 3 (1hour)
Continuous Salbutamol nebulisers for 1 hour
Obtain IV access
Capillary blood gas, U+E, FBC, Blood glucose
Constant observation required with senior medical (consultant) input.
Move patient to High Dependency care.
Step 4
IV Medication
IV Hydrocortisone :
IV Magnesium
4mg/kg (max 100mg)
6hrly
50mg/kg MgSO4 (max 2g) over 20 mins
(Grade 2A)
Cheuk et al Arch Dis Child (Metanalysis)
Should be used in severe asthma, or moderate asthma
deteriorating despite β2 agonist/ipratropium/IV steroid
IV Salbutamol
Loading dose 15mcg/kg over 15 mins
Maintenance
(Grade 2B)
2-5mcg/kg/min
Nebulised Salbutamol continued half hourly
ECG monitoring and monitor serum potassium regularly
Contact PICU for advice / retrieval unless senior (consultant) medical staff are happy
that adequate control is being gained.
Step 5
Intravenous Salbutamol: Max 10 mcg/kg/min in consultation with PICU
Repeat capillary blood gas, blood potassium and blood glucose .
(continue to monitor potassium regularly)
Apply Emla/Ametop cream should a second cannula be required
Contact PICU for advice / retrieval
Step 6
Ondansetron: 0.1mg/kg (max 4mg)
IV Aminophyline: Loading dose 5mg/kg over 20 mins
Maintenance 1mg/kg/hr
Do not mix with intravenous Salbutamol
Repeat capillary blood gas, blood potassium and blood glucose
Contact an Anaesthetist to review patient.
Ongoing discussion with PICU
Indications for Intubation in Severe Asthma
Decision made on case by case basis
Reserved for cases who continue to deteriorate despite maximal medical
treatment.
Estimated 2-3% mortality in children ventilated for acute severe asthma
Securing the airway does not cure the problem:
Instrumenting reactive airway
CV instability
Difficulties with ventilation remain
No guideline or consensus to predict precisely when ETT may be required
Fatigue/somnolence/reduced conscious level
O2 despite FiO2
Progressive CO2 despite maximal treatment
Unable to speak/exhausted from work of breathing
Respiratory/cardiorespiratory arrest
RSI:
Preoxygenation
Ketamine + Fentanyl + Suxamethonium (likely BP)
Microcuff ETT
Maintenance:
Sedation/ NMB (avoid histamine releasing drugs)
A-line
IV fluids
Regular IV Hydrocortisone
MgSO4 to keep levels upper end normal
Physio and saline nebs
PRVC:
Copes with changes in resistance/compliance and limits barotrauma
Cautious PEEP/ low tidal volume/ increased expiratory time
Permissive hypercapnoea/ accept pH ≥ 7.2
Vigilance for breath stacking/pneumothorax
OSA in Children
Definition:
Episodic partial or complete airway obstruction during sleep, resulting in
disrupted sleep and abnormal gas exchange.
Incidence:
Affects 1-5% of children at any age, most common between 2-6 years
M:F
1:1
(changes post puberty 2M:1F by adulthood)
Risk factors:
Adenotonsillar Hypertrophy
BMI (Hannon et al Jpaediatrics 2012 Adolescents with BMI >97th centile, 45% OSA on PSG)
Other Risk Factors
Craniofacial abnormalities (micrognathia, retrognathia, midface hypoplasia)
Neuromuscular disorders/CP (altered tone)
Macroglossia (mucopolysaccharidosis, Beckwith Wiedemann, hypothyroidism)
Downs (midface hypoplasia, macroglossia, reduced tone)
HbS
What’s the Problem?
Sleep fragmentation
Intermittent hypoxia/elevated CO2
Increased work of breathing

Neuroapoptosis in developing brain
Reduced memory
Reduced learning performance
PAP (>35% with mod/severe OSA)
Snoring 
Obstructive

Hypoventilation
OSA
3-12% of children snore at night.
Presence of snoring not diagnostic of OSA
Absence of snoring can’t exclude OSA
(peak obstruction during REM sleep, when muscle tone is lowest. REM
usually during final third of sleep when least likely to be observed by parent).
History
Snoring (loud, ≥3 night/week suspicious of OSA)
Witnessed apnoeas
Restless sleep/night terrors/frequent waking/enuresis
Sweating
Sleep position (side, neck flexion, AO extension)
Daytime sleepiness (school, car journeys, reading, watching TV)
Morning headaches/difficulty waking
Inattention/poor concentration/behaviour problems/hyperactivity
Even well validated questionnaires are not reliable for diagnosis or exclusion of OSA
(sensitivity & specificity 50-60%)
Audio/video recordings and overnight SaO2 all have low NPV (negative result
insufficient to exclude OSA).
Polysomnography
Gold Standard for diagnosis/exclusion
of OSA in infants/children/adults
Measure
Oral and nasal airflow
Abdominal/chest wall movement
ETCO2/transcutaneous CO2
SaO2
ECG
Snore microphone
EEG/EMG (face/leg movement)
Electrooculography (detect eyes open/shut)
Has to be in a sleep lab, overnight and
interpreted by specialist in sleep medicine
Polysomnography (PSG) Report
AHI
Severity
(no classification uniformly accepted)
AHI:
SaO2 Nadir
(92% lowest nadir in normal sleeping children)
Number of apnoeas+hypopnoeas/hour of sleep recorded
AHI ≥ 1 with relevant symptoms, diagnostic for OSA
Apnoea: >90% reduction in airflow lasting ≥90% duration of 2 breaths
Obstructive: inspiratory effort during reduced airflow
Central: no inspiratory effort during reduced airflow
Hypopnoea: ≥30% reduction in airflow lasting ≥90% duration of 2 breaths
Assoc. with arousal or transient SaO2 ≥3%
Obstructive/ central/ mixed
First Line Treatment
Adenotonsillectomy +/- Weight Optimisation
Tonsillectomy alone less effective
Adenoidectomy alone not recommended for OSA management
Size of tonsils and adenoids does not correlate with presence/severity of OSA
or response to resection
Obese/craniofacial abnormality/abnormal tone/severe OSA: less likely to
normalise PSG, but AHI should decrease
FTT and PAP should resolve
Conflicting results as to whether school performance improves
Friedmann et al Otolarygology, Head and Neck surgery 2009
(>1000 children 58.9% completely PSG after adenotonsillectomy)
Marcus et al NEJM 2013
(464 children 5-9 years, normal PSG 7 months later in 79% after adenotonsillectomy vs
46% without surgery)
Anaesthetic Management
Preop Assessment:
History (sleep, current/recent RTi, comorbidity)
Examination (BMI, FTT, facial appearance, mouth/nasal breather, pectus excavatum)
Investigations (PSG)
? Ward or HDU postop
Recognised Risk Factors of Respiratory Compromise Post Adenotonsillectomy
(Grade 1B)
Age <3 years
Severe OSA on PSG (AHI ≥ 24/hr, SaO2 nadir ≤ 80%)
Abnormal airway tone/structure (NM disease/craniofacial/BMI)
FTT
Recent RTi
Cardiac Complications of OSA (PHT, RVH)
Preop Analgesia: Paracetamol (15mg/kg)/Ibuprofen (10mg/kg)
Induction:
Propofol 1%+Remifentanil (5mcg/ml) TCI
or
Propofol bolus + Remi bolus (2mcg/kg)
Maintenance: Propofol+Remi TCI
or
O2+N2O+Des
IV Hartmanns 10ml/kg bolus  maintenance
Ondansatron (0.1mg/kg) + Dexamethasone (0.15mg/kg)
Morphine (25-100mcg/kg)
Postop
SaO2 monitoring for any child with OSA
Avoid supplementary O2
Analgesia * AVOIDING CODEINE*
IV fluid at maintenance rate till drinking well
Post op Analgesia in Hospital
Children having tonsillectomy will receive multimodal analgesia from their
anaesthetist in theatre. Unless there are contraindications specific to an individual
patient, for inpatient analgesia postoperatively the anaesthetist will prescribe:
Paracetamol
15mg/kg
4 hourly PRN
Ibuprofen
10mg/kg
6 hourly PRN
Morphine solution
100-300
2 hourly PRN (maximum 6 doses in 24
hours)
micrograms/kg
(maximum per dose 10mg)
In line with recent recommendations from the MHRA and the APA (Association of
Paediatric Anaesthetists) no children having tonsillectomy should receive Codeine
postoperatively, either in hospital or at home.
For discharge home these children should be prescribed:
Paracetamol
as per discharge analgesia guidelines
Ibuprofen
as per discharge analgesia guidelines
Morphine Solution
200micrograms/kg (maximum per dose 10mg)
3 postoperative doses to be given on the mornings of day 3, day 4 and day 5 (day
of surgery being day 0). For children below 2 years please seek Pain Team advice.
On discharge home please ensure parents receive a copy of the Parent
Information Leaflet ‘Pain Relief after Tonsillectomy’. This provides guidance on
giving children regular pain relief post tonsillectomy, the signs to look out for in
children receiving opioid medications and when to seek medical attention.
Analgesia Post Adenoidectomy
Children having adenoidectomy alone will receive multimodal analgesia from
their anaesthetist in theatre.
In line with recent recommendations from the MHRA and the APA
(Association of Paediatric Anaesthetists) no children having adenoidectomy
should receive Codeine postoperatively, either in hospital or at home.
For these children paracetamol and ibuprofen postoperatively on the ward and
for discharge home should be sufficient.
Guideline for Postop Monitoring of Patients with OSA
This includes a spectrum of patients, ranging from mild through moderate to severe OSA. Excluding those
with severe OSA, or those with significant co-morbidity (listed below), the majority of patients should be able
to return to ward 3 postoperatively.
Mild, Mild/Moderate, Moderate or Moderate/Severe OSA with
SaO2 ≥ 60% on Sleep Study
Return to a monitored bed on ward 3 opposite the nurse’s station, to facilitate close observation.
SaO2 should be monitored during all periods of sleep until achieve restful sleep with SaO2 ≥ 90% overnight.
If SaO2 < 90% on air, over a 5 minute period despite repositioning, the anaesthetist and surgeon involved in
the case should be contacted. If this occurs out of hours the PICU fellow and PICU Band 7 should be
contacted.
If PET criteria are met a PET call should be activated.
In this patient group the most likely cause of desaturation is airway obstruction, therefore managing
desaturations with supplementary O2 alone is not appropriate.
Noisy breathing or restlessness during sleep are also signs of airway obstruction and warrant review.
Patient transfer from ward 3 to HDU requires Consultant to Consultant referral, therefore both the on call
PICU consultant and ENT consultant should be informed.
Severe OSA with SaO2 < 60% on sleep study, or any grade of OSA plus
significant comorbidity including: Downs, craniofacial anomalies, age ≤
2years, neuromuscular disorders, obesity
Should consider postop admission to HDU under PICU care, for at least the first postop night.
This patient group usually come from, and therefore return to, the care of the respiratory team
on ward 1 following discharge from HDU.
Postop management may vary from this guideline at the discretion of the anaesthetist or surgeon
if there are airway concerns during induction, emergence or in recovery.
HDU admission under PICU care is mandatory for patients:
With adenoidal packs in situ
Requiring an NPA
Following removal of an NPA patients must remain on HDU under PICU care until they
maintain SaO2 ≥ 90% during sleep. They can then return to a monitored bed on ward 3,
where SaO2 should be monitored during sleep for a further 24 hours at least.
Referral to the Respiratory team is appropriate for patients who > 2 days
postop:
Have noisy breathing awake
Have signs of increased respiratory effort
Are restlessness with noisy breathing during sleep
Have SaO2 < 90% on air with witnessed obstructive episodes
We’ve Discussed
Management of Children with RTi
Management of Children with Acute Severe Asthma
Management of Children with OSA
Questions
????????