Common Paediatric Respiratory conditions

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Common Paediatric
Respiratory conditions
Corrine Balit
Outline
 Respiratory Distress : Signs and Treatment
 Respiratory Supports
 High Flow Nasal prong
 CPAP/ BIPAP
 Ventilation
 Bronchiolitis
 Pertussis
 Asthma
Case 1: 6 week old E.L.
 6 week old infant presents with severe respiratory
distress
 Taken to resuscitation bay on arrival
 Call from ED doctor asking for help
 Resp
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



RR 90
Tracheal tug
Intercostal and subcostal recession
Grunting
Head bobbing, nasal flaring
 CVS
 HR 200
 Cap refill 3 seconds
 Mottled
 Neuro
 Agitated,
 Unsettled,
Respiratory Distress/ Failure
 One of most common reason ICU will need to review a
patient
 Hard to determine which patients will need to come to
ICU
 Clinical assessment and reassessment is most important
 May need to start some basic measures and then
reassess again.
Increased work of
breathing
Malformations of
chest wall
Evidence of
hypoxemia/hyperca
rbia
Tachypnea
Large A diameter
(barrel chest)
Agitation
Nasal Flaring
Narrow AP diameter
Confusion
Chest wall
retractions
Somnolence
Paradoxical
breathing
Cyanosis
Agitation
Grunting
Accessory muscle
use
Investigations
 Venous Blood Gas
 Carbon dioxide and pH
 Lactate
 Oximetry
 Chest x-ray
 Other investigations to support underlying cause.
Who needs to come to ICU
 Clear cut ones that do and don’t
 In-between that is the hardest.
 Indications






Mod- Severe respiratory distress despite basic treatment
Recurrent apnoeas
Respiratory acidosis (pH < 7.2)
Increasing oxygen requirements
Change in mental state
Needing airway protection
Treatment of Respiratory Failure
 Administration of supplemental oxygen + consider
humidification
 Evaluation of airway patency
 Clear secretions / Airway toileting to maintain airway
patency
 Appropriate adjuncts
 Salbutamol +/- ipratropium
 Steroids if indicated
Respiratory Distress
RR < 60
Mild-Mod Work of breathing
Oxygen requirement < 2L
Not irritable/agitated
RR >60
Mod-severe work of breathing
Increasing oxygen requirement
Irritable/agitated
Basic Measures
Nil by mouth
Cannula + IVF
Humidified oxygen total flow of 2-3L
Adjuncts appropriate to condition e.g.
salbutamol, steroids
Mod-Severe Respiratory Distress
IV Cannula
Oxygen + humidification
Salbutamol, ipratropium,
steroids
Indications for ICU
- Ongoing mod-severe respiratory
distress despite above
- Apnoeas
- Respiratory Acidosis
- Fatigue
Treatment of Respiratory Distress
 Specific treatment for conditions
 Non-invasive support
 High Flow nasal prong oxygen
 CPAP
 BIPAP
 Mechanical ventilation
 IPPV
 HFOV
 ECMO
Treatment of Respiratory Distress
 Fluid Management
 Generally restricted if receiving ventilatory support
 Two- thirds maintenance
 Normal saline or Hartmann's as fluid for severe resp
distress
 Watch EUC
 Feeds
 Feed once stable and improving
 Can feed while receiving NIV support
High Flow Nasal Prong oxygen
 Delivered via nasal prong and using Fisher and Paykel
System
 Rational is two fold:
 High flows provide positive distending pressure to the
airway improving functional residual capacity
 Use of humidification
 Humidification improves mucocillary clearance
 Advantages:
 Tolerated better by children
 Avoid some of CPAP complication like nasal mucosal injury
High Flow Nasal Prong oxygen
 Flow rates currently recommended up to 8L/Min
 Prospective study in Brisbane where the used flow rates
between 1 and 8 L/min were used and they used
electrical impedance tomography and oesophageal
pressures measured.
 Found that using 8L/min flow rate delivered on average
a CPAP effect of 4 cm H20 in infants with viral
bronchiolitis
 Definition of High flow nasal prong cannula
 1L/kg/min
 Current cannula for paediatrics up to 8L flow.
High Flow- Indications
 Respiratory distress with hypoxemia
 Bronchiolitis
 Pneumonia
 Post extubation respiratory support
 Facilitation of weaning from CPAP
 Post operative respiratory failure
High Flow- Contraindications
 Nasal obstruction
 Choanal atresia
 Large polyps
 Foreign body aspiration
 Children requiring airway protection
 Severe life threatening hypoxia (not a replacement for
intubation
Non-Invasive Ventilation
 CPAP versus bi-level NIV
 Difficulties is with appropriate size mask
 Bubble CPAP good for infants (<10kg)
 PEEP 5-10cm
 Contraindications
 If airway protection is needed
 Decreased level of consciousness
 Nasal obstruction
Invasive Ventilation
 Conventional Ventilation
 High Frequency Ventilation
 If intubating patient for severe respiratory distress
suggest always using cuffed tube.
 Cuff doesn’t need to go up but there if you need it
Bronchiolitis
Bronchiolitis- aeitology
 Respiratory Syncytial Virus
 Para influenza virus
 Adenovirus
 Influenza virus
 Rhinoviruses
 Human metapneumovirus
Bronchiolitis- Pathology
 Loss of epithelial cells
 Cellular infiltration
 Oedema around airway
 Plugging of airway with mucus
 Can get complete and partial plugging of airways
resulting in localised atelectasis and over distention in
other areas.
 Imbalance of ventilation and perfusion leads to
hypoxemia.
Bronchiolitis – Clinical Features
 Coryzal symptoms
 Wheezing
 Pneumonia
 Aponea
 Hyponatremia
 Seizures
 Encephalopathy
 Myocarditis
Investigations
 NPA
 Blood Gas
 CXR
 Septic workup if severe or very young
 FBC, EUC
Bronchiolitis- Indications for ICU
admission
 Recurrent Apnoea
 Slow irregular breathing
 Decreased level of consciousness
 Shock
 Exhaustion
 Hypoxia
 Respiratory acidosis
Bronchiolitis- Management
 Supportive Care
 Oxygen
 Suction
 Fluids / Feeding
 Always Nil by mouth if moderate- severe
 IV fluids : 2/3 maintenance if moderate- Severe
 NG Tube
 Decompression of stomach
 Feeds once more stable
 Infection Control
Bronchiolitis – Specific Treatments
 Bronchodilators
 Surfactant
 Corticosteroids
 Ribavirin
 RSV Immunoglobulin
 Palivizumab
 Antibiotics
Bronchiolitis – Specific Treatments
Bronchodilators
 B- agonists
 Meta analysis: modest short term improvement in clinical
scores, without changes in oxygen saturation, rate of
hospitilisation or length of hospital stay
 Adrenaline
 RCT comparing adrenaline nebulised with placebo
 No difference in length of hospital stay and no short term
or long term clinical improvement
Bronchiolitis – Specific Treatments
 Corticosteroids
 Controversial, conflicting studies
 Cochrane review: no benefits in either length of stay or
clinical course in infants
 Surfactant
 Promising as RSV affects endogenous surfactant production
 given to mechanically ventilated infants with RSV –
shortened time on mechanical ventilation,
 Individual case reports and series.
 Limited evidence, very expensive
Bronchiolitis – Specific Treatments
Ribavirin
 Antiviral
 Inhibits RSV replication
 Evidence supports aerolised use, IV can be given
 Early trials showed it to be effective
 No convincing benefit on clinical outcomes expect to
patients post BMT with RSV
Bronchiolitis – Specific Treatments
 RSV- IG IV
 No improvement on clinical outcome
 Palivizumab
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Monoclonal antibody
For prophylaxis for high risk infants
Expensive
50% decrease in need for hospitlisation in high risk infants
Bronchiolitis – Specific Treatments
 Ipratropium bromide
 Not been demonstrated to be efficacious
 Heliox
 Helium-oxygen gas
 Prospective study looking at 70% helium, 30% oxygen
mixture- improved tachypnoea and tachycardia and shorter
stay in PICU
 Nitric oxide
 Case reports only
Bronchiolitis: Antibiotics
 Used for secondary bacterial infection
 Traditionally risk of secondary infection with RSV
thought to be low but theses studies based on children
not admitted to PICU.
 Recent studies: PCCM 2010
 Secondary pneumonia in patients in PICU with RSV reported
to be as high as 20-50%
 If child is unwell enough to be admitted to PICU with
bronchiolitis, cultures should be taken and antibiotics
started
Levin et al PCCM 2010
 Prospective study looking at patients admitted with RSV
bronchiolitis with progressive respiratory failure
 Excluded patients who had pre-existing conditions
 Found 39% had probable pneumonia by tracheal aspirate
 Concluded that due to high rate of possible secondary
bacterial pneumonia, empirical antibiotics for 24-48 hrs
pending cultures may be justified in those sick enough
to come to PICU
Bronchiolitis- Ventilation
 High Flow Nasal Prongs
 CPAP
 Mechanical Ventilation
 IPPV
 HFOV
 ECMO
My Approach – to moderate-severe
bronchiolitis
 Suction and clear airway esp nasal passages
 Application of oxygen with humidification if possible
 Nil by mouth
 IV cannula + 2/3 maintaince IVF
 Obtain venous blood gas (BC + FBC/EUC at time of IVC)
 Decide on level of respiratory support
 High flow Nasal prong Cannula to 8L/min (not available in
ED)
 Bubble CPAP
 OG or NG if on respiratory support
 Constant reassessment, looking for
 Decreasing respiratory rate
 Decrease in work of breathing
 Heart rate improving
 If not responding to above to be intubated and
ventilated
 If sick enough with bronchiolitis to need ventilatory
support I do blood culture and sputum culture and cover
with antibiotics.
 Need to monitor Sodium
Pertussis
Pertussis - Pathology
 Bordetella Pertussis
 Toxin damages respiratory epithelium and can produce
systemic toxicity
 Severe, Prolonged Coughing
 Aponea in young infants
 Whoop- loud stridor on inspiration after a paroxysm
Pertussis- Severe Complications
 Pneumonia
 Pulmonary Hypertension
 Encephalopathy
 Seizures
 Global Myocardial dysfunction
Pertussis
 Mortality highest in
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Very young infants
WCC > 100 000
Presenting with pneumonia
Need for circulatory support
 Indications for ICU
 Apnoeas
 Seizure
 Severe respiratory failure
Pertussis - Investigations
 PCR on NPA
 CXR
 WCC
 ECHO if severe
Pertussis- Management
 Suction
 Oxygen
 Respiratory support
 High flow nasal o2
 CPAP
 Ventilation
 Antimicrobials
 Azithromycin
Pertussis- Other Management
 If leukocytosis (esp neutrophilia)
 Exchange transfusions or aphaeresis to remove white cells
 With high white cell count can get leukocyte aggregates in
pulmonary vessels
 If Pulmonary Hypertension present
 Consider inhaled nitric oxide or sildenafil
 If Severe respiratory failure
 ECMO
 Treat contacts
PCCM 2007
 Retrospective study from RCH Melbourne
 Median age at admission was 6 weeks
 94% of patients were unimmunised at time of admission
 Infants presenting with pneumonia had raised white cell
count
 38% needing intubation died
 All patients who needed ECMO died
Asthma
Asthma – Management
 Oxygen
 B-adrenergic agonists
 Corticosteroids
 Anticholinergic
 Magnesium Sulphate
 Theophylline/ Aminophylline
 Inhalational anaesthetics
Asthma- Management
 Helium-Oxygen
 Non-invasive ventilation
 Ventilation
 Ketamine
 Adrenaline
B-adrenergic agonists
 Salbutamol first line bronchodilator of choice
 MDI with spacer as effective as nebulisation
 When giving nebulisation, continuous nebulization is
superior to intermittent doses (Cochrane Review 2009)
 Provides sustained stimulation of B-receptors
 Promotes progressive bronchodilatation
 Improves drug delivery in distal airway
IV salbutamol
 Considered in patients unresponsive to treatment with
continuous nebulisation.
 RCT in children 2002:
 IV salbutamol as a bolus , atrovent or IV salbutamol
+atrovent
 In severe asthma, IV salbutamol as a bolus lead to more
rapid recovery
Ipratropium bromide
 Leads to bronchodilatation by decreasing
parasympathetic-mediated cholinergic bronchomotor
tone
 Cochrane review 2009:
 Adding multiple doses of anticholinergic to B2 agonists
appears safe and improves lung function
 Would avoid hospital admission in 1 of 12 such patients
 No studies in critically ill children admitted to PICU
 Because safe, considered reasonable to use
Magnesium Sulphate
 Acts as calcium antagonist leading to smooth muscle
relaxation
 5 x RCT looking at IV magnesium in children
 4 of these studies showed improvement in respiratory
function and decrease in hospital admissions
 1 study showed no significant difference between
magnesium and placebo group
 2 x meta analysis that showed adding magnesium
provided additional benefit to children
Methylxanthines
 Theophylline and Aminophylline
 Role is in severe asthma who have failed other
treatment
 Meta analysis of RCT in paeds found no benefit in mild
or moderate asthma
 RCT in 163 children with status asthmaticus
 Aminophylline improved oxygen sats and pulmonary
function
 No difference in length of stay
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