Paediatrics 1 Flashcards
1
Q
What are the 3 fetal shunts
A
Ductus Venosus
Foramen Ovale
Ductus arteriosus
2
Q
Ductus venosus function
A
Connects umbilical vein to IVC to bypass liver
3
Q
Foramen ovale function
A
Connects RA to LA allowing blood to bypass RV and pulmonary circulation
4
Q
Ductus arteriosus
A
Connects PA with aorta to allow blood to bypass pulmonary circulation
5
Q
How is the foramen ovale closed
A
First breaths of baby expands the alveoli, decreasing pulmonary vascular resistance (PVR)
Decrease in PVR causes a fall in RA pressure. Hence LA pressure is greater than RA, squashing atrial septum to cause functional closure.
6
Q
What keeps the ductus arteriosus open
A
Prostaglandins. Increased blood oxygenation causes a drop in circulating prostaglandins
7
Q
What is the ligamentum arteriosum a remnant of?
A
Ductus arteriosus
8
Q
How does ductus venosus become the ligamentum venosum
A
Ductus venosus stops functioning after birth due to umbilical cord clamping. No blood flows through umbilical vein and ductus venosus structurally closes.
9
Q
Innocent murmurs/flow murmurs
A
Fast blood flow through various areas of heart during systole
10
Q
Features of innocent murmurs (5)
A
Short Short Systolic Symptomless Situation dependent
11
Q
When to refer innocent murmur to cardiologist? (4)
A
Murmur louder than 2/3
Diastolic murmurs
Louder on standing
Symptoms - Failure to thrive, feeding difficulty, cyanosis, SOB
12
Q
Innocent murmurs investigations
A
ECG
CXR
Echo
13
Q
Pan-systolic murmurs DDx
A
Mitral regurgitation
Tricuspid regurgitation
VSD
14
Q
Ejection systolic murmurs
A
Aortic stenosis
Pulmonary stenosis
Hypertrophic obstructive cardiomyopathy
15
Q
Splitting of second heart sound pathophysiology
A
During inspiration, the chest wall and diaphragm pull the lungs open. This pulls the heart open. This causes Right side of heart to fill faster as it pulls blood in from venous system.
Increase in volume of the RV causes delay for RV emptying during systole so delay in pulmonary valve closure.
When the pulmonary valve closes slightly later than aortic, this causes second heart sound split
16
Q
ASD sound
A
mid-diastolic, crescendo-decrescendo murmur loudest at upper left sternal border WITH
fixed split second heart sound
17
Q
PDA sound
A
Normal first heart sound with a continuous crescendo-decrescendo machinery murmur that may continue during the second heart sound, making the second heart sound difficult to hear
18
Q
Tetralogy of Fallot sound
A
Ejection systolic murmur loudest at pulmonary area (arises from pulmonary stenosis)
19
Q
Cyanotic heart disease causes (4)
A
Heart defects that can cause right to left shunt
VSD
ASD
PDA
Transposition of great arteries
20
Q
Which heart defect will always have cyanosis
A
Transposition of the great arteries. As right side of the heart pumps blood directly into the aorta and systemic circulation.
21
Q
PDA?
A
When the ductus arteriosus fails to close
22
Q
Key risk factor of PDA
A
Prematurity
23
Q
Reasons for PDA?
A
Unclear but may be genetic/ due to maternal infections such as rubella.
24
Q
PDA pathophysiology
A
Pressure in the aorta is higher than that in the pulmonary vessels, so blood flows from the aorta to the pulmonary artery.
This creates a left to right shunt where blood from the left side of the heart crosses to the circulation from the right side.
This increases the pressure in the pulmonary vessels causing pulmonary hypertension, leading to RS heart strain as right ventricle struggles to contract against increased resistance.
This leads to RV hypertrophy and the increased blood flowing through the pulmonary vessels returning to LS of heart leads to LV hypertrophy.
25
PDA presentation (4)
SOB
Difficulty feeding
Poor weight gain
Lower RTI
26
PDA murmur
A small patent ductus arteriosus may not have any abnormal heart sounds. More significant PDAs cause a normal first heart sound with a continuous crescendo-decrescendo “machinery” murmur that may continue during the second heart sound, making the second heart sound difficult to hear.
27
PDA investigation
Diagnosis confirmed by echocardiogram. Effects of PDA e.g. hypertrophy also demonstrated.
The use of doppler flow studies during the echo can assess the size and characteristics of the left to right shunt.
28
PDA management
Patients monitored until 1 year of age using echocardiograms.
If not closed, trans-catheter/surgical closure performed.
29
ASD?
Defect in septum between the two atria.
30
ASD pathophysiology
During the development of the fetus the left and right atria are connected. Two walls grow downwards from the top of the heart, then fuse together with the endocardial cushion in the middle of the heart to separate the atria. These two walls are called the septum primum and septum secondum.
Defects this these two walls lead to atrial septal defects, a hole connecting the left and right atria. There is a small hole in the septum secondum called the foramen ovale. The foramen ovale normally closes at birth.
An atrial septal defect leads to a shunt, with blood moving between the two atria. Blood moves from the left atrium to the right atrium because the pressure in the left atrium is higher than the pressure in the right atrium. This means blood continues to flow to the pulmonary vessels and lungs to get oxygenated and the patient does not become cyanotic, however the increased flow to the right side of the heart leads to right sided overload and right heart strain. This right sided overload can lead to right heart failure and pulmonary hypertension.
Eventually pulmonary hypertension can lead to Eisenmenger syndrome. This is where the pulmonary pressure is greater than the systemic pressure, the shunt reverses and forms a right to left shunt across the ASD, blood bypasses the lungs and the patient becomes cyanotic.
31
Types of ASD (3)
Ostium secondum
Patent Foramen Ovale
Ostium Primum
32
Complications of ASD (4)
Stroke
AF/ atrial flutter
Pulmonary HTN and RS HF
Eisenmenger syndrome
33
ASD presentation
SOB
Difficulty feeding
Poor weight gain
Lower RTI
34
ASD management
Referral to paediatric cardiologist
Correction with transvenous catheter closure or open heart surgery
35
ASD murmur.
mid-systolic, crescendo-decrescendo murmur loudest at the upper left sternal border with a fixed split second heart sound. Splitting of the second heart sound is where you hear the closure of the aortic and pulmonary valves at slightly different times. This can be normal with inspiration, however a “fixed split” second heart sound means the split does not change with inspiration or expiration. This occurs in an atrial septal defect because blood is flowing from the left atrium into the right atrium across the atrial septal defect, increasing the volume of blood that the right ventricle has to empty before the pulmonary valve can close.
36
VSD associations?
Down's syndrome
| Turner's syndrome
37
VSD pathophysiology?
Due to the increased pressure in the left ventricle compared to the right, blood typically flows from left the right through the hole. Blood is still flowing around the lungs before entering the rest of the body, therefore they remain acyanotic (not cyanotic) because their blood is properly oxygenated. A left to right shunt leads to right sided overload, right heart failure and increased flow into the pulmonary vessels.
The extra blood flowing through the right ventricle increases the pressure in the pulmonary vessels over time, causing pulmonary hypertension. If this continues, the pressure in the right side of the heart may become greater than the left, resulting in the blood being shunted from right to left and avoiding the lungs. When this happens the patient will become cyanotic because blood is bypassing the lungs. This is called Eisenmenger Syndrome
38
VSD presentation
Often initially symptomless. Otherwise,
Poor feeding
Dyspnoea
Tachypnoea
Failure to thrive
39
Examination findings VSD
Pan-systolic murmur more prominently heard at the left lower sternal border in the 3rd & 4th intercostal spaces
There may be a systolic thrill on palpation.
40
Causes of pan-systolic murmurs
VSD
MR
TR
41
VSD treatment
Transvenous catheter closure via femoral vein/ open heart surgery
42
Complications of VSD and prevention
Increased risk of infective endocarditis.
Antibiotic prophylaxis should be considered during surgical procedures.
43
Eisenmenger syndrome?
Condition which occurs when blood flows from the right side of the heart to the left across a structural heart lesion, bypassing the lungs.
44
Lesions that can cause Eisenmenger syndrome
ASD
VSD
PDA
45
Eisenmenger syndrome pathophysiology
Normally when there is a septal defect blood will flow from the left side of the heart to the right. This is because the pressure in the left side is greater than in the right. Remember, the left ventricle has to pump blood through the entire body, whereas the right ventricle simply has to fill the lungs. A left to right shunt means blood still travels to the lungs and gets oxygenated, so the patient does not become cyanotic.
Over time the extra blood flowing into the right side of the heart and the lungs increases the pressure in the pulmonary vessels. This leads to pulmonary hypertension. When the pulmonary pressure exceeds the systemic pressure, blood begins to flow from the right side of the heart to the left across the septal defect. This is a right to left shunt. Essentially it becomes easier for the right side of the heart to pump blood across the defect into the left side of the heart compared with pumping blood into the lungs. This causes deoxygenated blood to bypass the lungs and enter the body. This causes cyanosis.
Cyanosis refers to the blue discolouration of skin relating to a low level of oxygen saturation in the blood. The bone marrow will respond to low oxygen saturations by producing more red blood cells and haemoglobin to increase the oxygen carrying capacity of the blood. This leads to polycythaemia, which is a high concentration of haemoglobin in the blood. Polycythaemia gives patients a plethoric complexion. A high concentration of red blood cells and haemoglobin make the blood more viscous, making patients more prone to developing blood clots.
46
Eisenmenger syndrome examination findings (4) (4)
RV heave
Loud P2: loud second heart sound due to forceful shutting of pulmonary valve
Raised JVP
Peripheral oedema
```
Findings related to right left shunt and chronic hypoxia
Cyanosis
Clubbing
Dyspnoea
Plethoric complexion
```
47
Eisenmenger syndrome management
Heart-lung transplant
48
Coarctation of the aorta
Congenital condition where there is narrowing of the aortic arch, usually around the ductus arteriosus
49
Coarctation of aorta association
Turners syndrome
50
Pressure distribution for coarctation of aorta
Reduces pressure of blood flowing to arteries distal to narrowing and increase in areas proximal to narrowing, such as first three branches of the aorta.
51
Coarctation of aorta presentation (7)
Weak femoral pulses in neonates
Systolic murmur may be heard below the left clavicle and below the left scapula
tachypnoea
Poor feeding
Grey and floppy baby
Left ventricular heave
Underdeveloped left arm where there is reduced flow to the left subclavian artery
Underdevelopment of legs
52
Coarctation of aorta management (2)
Prostaglandin E is used to keep ductus arteriosus open while waiting for surgery
Surgery is then performed to correct the coarctation and to ligate the ductus arteriosus.
53
What are the leaflets of the aortic valve called
aortic sinuses of valsalva
54
How many aortic valve leaflets would aortic stenosis patients have?
May have 1/2/3/4 leaflets
55
Aortic stenosis presentation (3)
SOB
Syncope on exertion
Angina
56
Aortic stenosis signs
The key examination finding is an ejection systolic murmur heard loudest at the aortic area, which is the second intercostal space, right sternal border. It has a crescendo-decrescendo character and radiates to the carotids.
Other signs that may be present on examination are:
Ejection click just before the murmur
Palpable thrill during systole
Slow rising pulse and narrow pulse pressure
57
Aortic stenosis investigation (2)
Echocardiogram
Follow up under paediatric cardiologist with echocardiograms, ECGs and exercise testing used to monitor progression
58
Aortic stenosis management
Percutaneous balloon aortic valvoplasty
Surgical aortic valvotomy
Valve replacement
59
Aortic stenosis complications (5)
```
Left ventricular outflow tract obstruction
Heart failure
Ventricular arrhythmia
Bacterial endocarditis
Sudden death, often on exertion
```
60
Pulmonary valve number of leaflets?
3
61
Pulmonary valve stenosis associations? (4)
Tetralogy of Fallot
William Syndrome
Noonan Syndrome
Congenital rubella syndrome
62
Pulmonary valve stenosis investigation
Echocardiogram
63
Pulmonary valve stenosis management
Mild symptoms - watch and wait
Balloon valvuloplasty via a venous catheter.
64
Tetralogy of Features
Ventricular septal defect (VSD)
Overriding aorta
Pulmonary valve stenosis
Right ventricular hypertrophy
65
TOF RF
Rubella infection
Increased age of the mother (over 40 years)
Alcohol consumption in pregnancy
Diabetic mother
66
TOF pathophysiology
The VSD allows blood to flow between the ventricles. The term “overriding aorta” refers to the fact that the entrance to the aorta (the aortic valve) is placed further to the right than normal, above the VSD. This means that when the right ventricle contracts and sends blood upwards, the aorta is in the direction of travel of that blood, therefore a greater proportion of deoxygenated blood enters the aorta from the right side of the heart.
Stenosis of the pulmonary valve provides greater resistance against the flow of blood from the right ventricle. This encourages blood to flow through the VSD and into the aorta rather than taking the normal route into the pulmonary vessels. Therefore, the overriding aorta and pulmonary stenosis encourage blood to be shunted from the right heart to the left, causing cyanosis.
The increased strain on the muscular wall of the right ventricle as it attempts to pump blood against the resistance of the left ventricle and pulmonary stenosis causes right ventricular hypertrophy, with thickening of the heart muscle.
These cardiac abnormalities cause a right to left cardiac shunt. This means blood bypasses the child’s lungs. Blood bypassing the lungs does not become oxygenated. Deoxygenated blood entering the systemic circulation causes cyanosis. The degree to which this happens is related mostly to the severity of the patients pulmonary stenosis.
67
TOF investigations
Echocardiogram
Doppler flow studies
CXR (boot shaped heart due to ventricular thickening)
68
TOF presentation (6)
Cyanosis (blue discolouration of the skin due to low oxygen saturations)
Clubbing
Poor feeding
Poor weight gain
Ejection systolic murmur heard loudest in the pulmonary area (second intercostal space, left sternal border)
“Tet spells”
69
Tet spells?
intermittent symptomatic periods where the right to left shunt becomes temporarily worsened, precipitating a cyanotic episode.
70
Tet spell treatment options
Older children squat, younger knees to chest
Supplementary oxygen is essential in hypoxic children as hypoxia can be fatal.
Beta blockers can relax the right ventricle and improve flow to the pulmonary vessels.
IV fluids can increase pre-load, increasing the volume of blood flowing to the pulmonary vessels.
Morphine can decrease respiratory drive, resulting in more effective breathing.
Sodium bicarbonate can buffer any metabolic acidosis that occurs.
Phenylephrine infusion can increase systemic vascular resistance.
71
What does squatting do for Tet spells
Squatting increases the systemic vascular resistance
72
TOF management and prognosis (2) (1)
In neonates, a prostaglandin infusion can be used to maintain the ductus arteriosus. This allows blood to flow from the aorta back to the pulmonary arteries.
Total surgical repair by open heart surgery is the definitive treatment, however mortality from surgery is around 5%.
Prognosis depends on the severity, however it is poor without treatment. With corrective surgery, 90% of patients will live into adulthood.
73
Ebstein's anomaly
Congenital heart condition where tricuspid valve is set lower in the RS of the heart (towards the apex), causing a bigger right atrium and a smaller right ventricle
74
Ebstein's anomaly presentation (6)
```
Evidence of heart failure (e.g. oedema)
Gallop rhythm heard on auscultation characterised by the addition of the third and fourth heart sounds
Cyanosis
Shortness of breath and tachypnoea
Poor feeding
Collapse or cardiac arrest
```
75
Ebstein's anomaly investigation
Echocardiogram
76
Ebstein's anomaly management (3)
Treating arrhythmias and heart failure.
Prophylactic antibiotics may be used to prevent infective endocarditis.
Definitive management is by surgical correction of underlying defect.
77
TGA?
Attachments of the aorta and the pulmonary trunk to the heart are swapped. This means the right ventricle pumps blood into the aorta and the left ventricle pumps blood into the pulmonary vessels.
78
TGA associations? (3)
VSD
Coarctation of aorta
Pulmonary stenosis
79
TGA diagnosis?
Often diagnosed with antenatal ultrasound scans.
80
TGA presentation (1)
Where defect was not detected during pregnancy, it will present with cyanosis at or within few days of birth.
81
TGA management
Prostaglandin infusion can be used to maintain ductus arteriosus (allows blood from aorta to flow to PA for oxygenation)
Balloon septostomy
Open heart surgery with cardiopulmonary bypass machine to perform an arterial switch procedure within few days of birth.
82
Bronchiolitis?
Bronchiolitis describes inflammation and infection in the bronchioles, the small airways of the lungs.
83
Bronchiolitis cause
Respiratory syncytial virus
84
Epidemiology bronchiolitis
Bronchiolitis is very common in winter. Bronchiolitis is generally considered to occur in children under 1 year. It is most common in children under 6 months. It can rarely be diagnosed in children up to 2 years of age, particularly in ex-premature babies with chronic lung disease.
85
Bronchiolitis presentation (8)
```
Coryzal symptoms. These are the typical symptoms of a viral upper respiratory tract infection: running or snotty nose, sneezing, mucus in throat and watery eyes.
Signs of respiratory distress
Dyspnoea (heavy laboured breathing)
Tachypnoea (fast breathing)
Poor feeding
Mild fever (under 39ºC)
Apnoeas are episodes where the child stops breathing
Wheeze and crackles on auscultation
```
86
Signs of respiratory distress (8)
```
Raised respiratory rate
Use of accessory muscles of breathing, such as the sternocleidomastoid, abdominal and intercostal muscles
Intercostal and subcostal recessions
Nasal flaring
Head bobbing
Tracheal tugging
Cyanosis (due to low oxygen saturation)
Abnormal airway noises
```
87
Reasons for admission for bronchiolitis
Aged under 3 months or any pre-existing condition such as prematurity, Downs syndrome or cystic fibrosis
50 – 75% or less of their normal intake of milk
Clinical dehydration
Respiratory rate above 70
Oxygen saturations below 92%
Moderate to severe respiratory distress, such as deep recessions or head bobbing
Apnoeas
Parents not confident in their ability to manage at home or difficulty accessing medical help from home
88
Bronchiolitis management
Typically patients only require supportive management. This involves:
Ensuring adequate intake. This could be orally, via NG tube or IV fluids depending on the severity. It is important to avoid overfeeding as a full stomach will restrict breathing. Start with small frequent feeds and gradually increase them as tolerated.
Saline nasal drops and nasal suctioning can help clear nasal secretions, particularly prior to feeding
Supplementary oxygen if the oxygen saturations remain below 92%
Ventilatory support if required
There is little evidence for treatments such as nebulised saline, bronchodilators, steroids and antibiotics.
Ventilatory Support
As breathing gets harder, the child gets more tired and less able to adequately ventilate themselves. They may require ventilatory support to maintain their breathing. This is stepped up until they are adequately ventilated:
High-flow humidified oxygen via tight nasal cannula (i.e. “Airvo” or “Optiflow”). This delivers air and oxygen continuously with some added pressure, helping to oxygenate the lungs and prevent the airways from collapsing. It adds “positive end-expiratory pressure” (PEEP) to maintain the airway at the end of expiration.
Continuous positive airway pressure (CPAP). This involves using a sealed nasal cannula that performs in a similar way to Airvo or Optiflow, but can deliver much higher and more controlled pressures.
Intubation and ventilation. This involves inserting an endotracheal tube into the trachea to fully control ventilation.
Palivizumab
Palivizumab is a monoclonal antibody that targets the respiratory syncytial virus. A monthly injection is given as prevention against bronchiolitis caused by RSV. It is given to high risk babies, such as ex-premature and those with congenital heart disease.
It is not a true vaccine as it does not stimulate the infant’s immune system. It provides passive protection by circulating the body until the virus is encountered, as which point it works as an antibody against the virus, activating the immune system to fight the virus. The levels of circulating antibodies decrease over time, which is why a monthly injection is required.
89
Viral induced wheeze
Viral-induced wheeze describes is an acute wheezy illness caused by a viral infection
90
Viral induced wheeze differentiation from asthma
The distinction between a viral-induced wheeze and asthma is not definitive. Generally, typical features of viral-induced wheeze (as opposed to asthma) are:
Presenting before 3 years of age
No atopic history
Only occurs during viral infections
Asthma can also be triggered by viral or bacterial infections, however it also has other triggers, such as exercise, cold weather, dust and strong emotions. Asthma is historically a clinical diagnosis, and the diagnosis is based on the presence of typical signs and symptoms along with variable and reversible airflow obstruction.
91
Viral induced wheeze presentation
Evidence of a viral illness (fever, cough and coryzal symptoms) for 1-2 days preceding the onset of:
Shortness of breath
Signs of respiratory distress
Expiratory wheeze throughout the chest
TOM TIP: Neither viral-induced wheeze or asthma cause a focal wheeze. If you hear a focal wheeze be very cautious and investigate further for a focal airway obstruction such as an inhaled foreign body or tumour. These patients will require an urgent senior review.
92
Viral induced wheeze management
Management of viral-induced wheeze is the same as acute asthma in children.
93
Acute asthma?
An acute exacerbation of asthma is characterised by a rapid deterioration in the symptoms of asthma.
94
Asthma triggers (3)
This could be triggered by any of the typical asthma triggers, such as infection, exercise or cold weather.
95
Acute asthma presentation (6)
Progressively worsening shortness of breath
Signs of respiratory distress
Fast respiratory rate (tachypnoea)
Expiratory wheeze on auscultation heard throughout the chest
The chest can sound “tight” on auscultation, with reduced air entry
A silent chest is an ominous sign. This is where the airways are so tight it is not possible for the child to move enough air through the airways to create a wheeze. This might be associated with reduce respiratory effort due to fatigue. A less experienced practitioner may think because there is no respiratory distress and no wheeze the child is not as unwell, however in reality this a silent chest is life threatening.
96
Moderate asthma severity (3)
Peak flow > 50 % predicted
Normal speech
No features listed across
97
Severe asthma criteria (6)
Peak flow < 50% predicted
Saturations < 92%
Unable to complete sentences in one breath
Signs of respiratory distress
Respiratory rate:
> 40 in 1-5 years
> 30 in > 5 years
Heart rate
> 140 in 1-5 years
> 125 in > 5 years
98
Life threatening asthma criteria (7)
```
Peak flow < 33% predicted
Saturations < 92%
Exhaustion and poor respiratory effort
Hypotension
Silent chest
Cyanosis
Altered consciousness / confusion
```
99
Acute asthma management
Staples of management in acute viral induced wheeze or asthma are:
Supplementary oxygen if required (i.e. oxygen saturations less than 94% or working hard)
Bronchodilators (e.g. salbutamol, ipratropium and magnesium sulphate)
Steroids to reduce airway inflammation: prednisone (orally) or hydrocortisone (intravenous)
Antibiotics only if a bacterial cause is suspected (e.g. amoxicillin or erythromycin)
Bronchodilators are stepped up as required:
Inhaled or nebulised salbutamol (a beta-2 agonist)
Inhaled or nebulised ipratropium bromide (an anti-muscarinic)
IV magnesium sulphate
IV aminophylline
Mild cases can be managed as an outpatient with regular salbutamol inhalers via a spacer (e.g. 4-6 puffs every 4 hours).
Moderate to severe cases require a stepwise approach working upwards until control is achieved:
Salbutamol inhalers via a spacer device: starting with 10 puffs every 2 hours
Nebulisers with salbutamol / ipratropium bromide
Oral prednisone (e.g. 1mg per kg of body weight once a day for 3 days)
IV hydrocortisone
IV magnesium sulphate
IV salbutamol
IV aminophylline
If you haven’t got control by this point the situation is very serious. Call an anaesthetist and the intensive care unit. They may need intubation and ventilation. This call should be made earlier to give the best chance of successfully intubating them before the airway becomes too constricted.
100
Acute asthma step down management
Once control is established: you can gradually work your way back down the ladder as they get better:
Review the child prior to the next dose of their bronchodilator.
Look for evidence of cyanosis (central or peripheral), tracheal tug, subcostal recessions, hypoxia, tachypnoea or wheeze on auscultation.
If they look well, consider stepping down the number and frequency of the intervention.
A typical step down regime of inhaled salbutamol is 10 puffs 2 hourly then 10 puffs 4 hourly then 6 puffs 4 hourly then 4 puffs 6 hourly.
Consider monitoring the serum potassium when on high doses of salbutamol as it causes potassium to be absorbed from the blood into the cells.
101
Presentation Suggesting a Diagnosis of Asthma (8)
Episodic symptoms with intermittent exacerbations
Diurnal variability, typically worse at night and early morning
Dry cough with wheeze and shortness of breath
Typical triggers
A history of other atopic conditions such as eczema, hayfever and food allergies
Family history of asthma or atopy
Bilateral widespread “polyphonic” wheeze heard by a healthcare professional
Symptoms improve with bronchodilators
102
Presentation suggesting diagnosis other than asthma (5)
Wheeze only related to coughs and colds, more suggestive of viral induced wheeze
Isolated or productive cough
Normal investigations
No response to treatment
Unilateral wheeze suggesting a focal lesion, inhaled foreign body or infection
103
Typical asthma triggers (6)
```
Dust (house dust mites)
Animals
Cold air
Exercise
Smoke
Food allergens (e.g. peanuts, shellfish or eggs)
```
104
Asthma diagnosis (5)
There is no gold standard test or diagnostic criteria for asthma. A diagnosis is made clinically based on a typical history and examination. Children are usually not diagnosed with asthma until they are at least 2 to 3 years old. When there is a low probability of asthma and the child is symptomatic, consider referral to a specialist for diagnosis.
When there is an intermediate or high probability of asthma, a trial of treatment can be implemented and if the treatment improves symptoms a diagnosis can be made.
There are investigations that can be used where there is an intermediate probability of asthma or diagnostic doubt:
Spirometry with reversibility testing (in children aged over 5 years)
Direct bronchial challenge test with histamine or methacholine
Fractional exhaled nitric oxide (FeNO)
Peak flow variability measured by keeping a diary of peak flow measurements several times a day for 2 to 4 weeks
105
Chronic Asthma management
Depends on age
106
Chronic Asthma management <5
Start a short-acting beta-2 agonist inhaler (e.g. salbutamol) as required
Add a low dose corticosteroid inhaler or a leukotriene antagonist (i.e. oral montelukast)
Add the other option from step 2.
Refer to a specialist.
107
Chronic Asthma management 5-12
Start a short-acting beta-2 agonist inhaler (e.g. salbutamol) as required
Add a regular low dose corticosteroid inhaler
Add a long-acting beta-2 agonist inhaler (e.g. salmeterol). Continue salmeterol only if the patient has a good response.
Titrate up the corticosteroid inhaler to a medium dose. Consider adding:
Oral leukotriene receptor antagonist (e.g. montelukast)
Oral theophylline
Increase the dose of the inhaled corticosteroid to a high dose.
Referral to a specialist. They may require daily oral steroids.
108
Chronic asthma management >12
Start a short-acting beta 2 agonist inhaler (e.g. salbutamol) as required
Add a regular low dose corticosteroid inhaler
Add a long-acting beta-2 agonist inhaler (e.g. salmeterol). Continue salmeterol only if the patient has a good response.
Titrate up the corticosteroid inhaler to a medium dose. Consider a trial of an oral leukotriene receptor antagonist (i.e. montelukast), oral theophylline or an inhaled LAMA (i.e. tiotropium).
Titrate the inhaled corticosteroid up to a high dose. Combine additional treatments from step 4, including the option of an oral beta 2 agonist (i.e. oral salbutamol). Refer to specialist.
Add oral steroids at the lowest dose possible to achieve good control under specialist guidance.
109
Do corticosteroids slow growth
There is evidence that inhaled steroids can slightly reduce growth velocity and can cause a small reduction in final adult height of up to 1cm when used long term (for more than 12 months). This effect was dose-dependent, meaning it was less of a problem with smaller doses.
110
Pneumonia?
Pneumonia is simply an infection of the lung tissue. It causes inflammation of the lung tissue and sputum filling the airways and alveoli.
111
Pneumonia presentation (7)
```
Cough (typically wet and productive)
High fever (> 38.5ºC)
Tachypnoea
Tachycardia
Increased work of breathing
Lethargy
Delirium (acute confusion associated with infection)
```
112
Pneumonia signs (9)
```
Tachypnoea (raised respiratory rate)
Tachycardia (raised heart rate)
Hypoxia (low oxygen)
Hypotension (shock)
Fever
Confusion
```
Bronchial breath sounds. These are harsh breath sounds that are equally loud on inspiration and expiration. These are caused by consolidation of the lung tissue around the airway.
Focal coarse crackles caused by air passing through sputum similar to using a straw to blow into a drink.
Dullness to percussion due to lung tissue collapse and/or consolidation.
113
Pneumonia causes (6) (3)
Bacterial
Streptococcus pneumonia is most common
Group A strep (e.g. Streptococcus pyogenes)
Group B strep occurs in pre-vaccinated infants, often contracted during birth as it often colonises the vagina.
Staphylococcus aureus. This causes typical chest xray findings of pneumatocoeles (round air filled cavities) and consolidations in multiple lobes.
Haemophilus influenza particularly affects pre-vaccinated or unvaccinated children.
Mycoplasma pneumonia, an atypical bacteria with extra-pulmonary manifestations (e.g. erythema multiforme).
Viral
Respiratory syncytial virus (RSV) is the most common viral cause
Parainfluenza virus
Influenza virus
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Pneumonia investigations (3)
A chest xray is the investigation of choice for diagnosing pneumonia. It is not routinely required, but can be useful if there is diagnostic doubt or in severe or complicated cases.
Sending sputum cultures and throat swabs for bacterial cultures and viral PCR can establish the causative organism and guide treatment.
All patients with sepsis should have blood cultures. Capillary blood gas analysis can be helpful in assessing or monitoring respiratory or metabolic acidosis and the blood lactate level in unwell patients.
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Pneumonia management (3)
Amoxicillin is often used first line. Adding a macrolide (erythromycin, clarithromycin or azithromycin) will cover atypical pneumonia. Macrolides can be used as monotherapy in patients with a penicillin allergy.
IV antibiotics can be used when there is sepsis or a problem with intestinal absorption.
Oxygen is used as required to maintain saturations above 92%.
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Croup?
Croup is an acute infective respiratory disease affecting young children. It is an upper respiratory tract infection causing oedema in the larynx.
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Croup epidemiology
It typically affects children aged 6 months to 2 years, however they can be older.
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Causes of croup (5)
Parainfluenza
Influenza
Adenovirus
Respiratory Syncytial Virus (RSV)
Croup used to be caused by diphtheria. Croup caused by diphtheria leads to epiglottitis and has a high mortality. Vaccination mean that this is very rare in developed countries.
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Croup presentation (5)
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Increased work of breathing
“Barking” cough, occurring in clusters of coughing episodes
Hoarse voice
Stridor
Low grade fever
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Croup severe management (5)
Most cases can be managed at home with simple supportive treatment (fluids and rest). During attacks it can help to sit the child up and comfort them. Measures should be taken to avoid spreading infection, for example hand washing and staying off school.
Oral dexamethasone is very effective. This is usually a single dose of 150 mcg/kg, which can be repeated if required after 12 hours. Prednisolone is sometimes used as an alternative where dexamethasone in not available (e.g. by GPs).
Stepwise options in severe croup to get control of symptoms:
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Oral dexamethasone
Oxygen
Nebulised budesonide
Nebulised adrenalin
Intubation and ventilation
```
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Epiglottitis management
Epiglottitis is inflammation and swelling of the epiglottis caused by infection, typically with haemophilus influenza type B.
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Presentation of epiglottitis (8)
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Patient presenting with a sore throat and stridor
Drooling
Tripod position, sat forward with a hand on each knee
High fever
Difficulty or painful swallowing
Muffled voice
Scared and quiet child
Septic and unwell appearance
```
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Epiglottitis investigation (1)
If the patient is acutely unwell and epiglottitis is suspected then investigations should not be performed. Performing a lateral xray of the neck shows a characteristic “thumb sign” or “thumbprint sign”. This is a soft tissue shadow that looks like a thumb pressed into the trachea. This is caused by the oedematous and swollen epiglottis. Neck xrays are also useful for excluding a foreign body.
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Laryngomalacia?
Laryngomalacia is a condition affecting infants, where the part of the larynx above the vocal cords (the supraglottic larynx) is structured in a way that allows it to cause partial airway obstruction. This leads to a chronic stridor on inhalation, when the larynx flops across the airway as the infant breathes in.
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Laryngomalacia structural changes
There are two aryepiglottic folds at the entrance of the larynx. They run between the epiglottis and the arytenoid cartilages. They are either side of the airway and their role is to constrict the opening of the airway to prevent food or fluids entering the larynx and trachea. In laryngomalacia the aryepiglottic folds are shortened, which pulls on the epiglottis and changes it shape to a characteristic “omega” shape.
The tissue surrounding the supraglottic larynx is softer and has less tone in laryngomalacia, meaning it can flop across the airway. This happens particularly during inspiration, as the air moving through the larynx to the lungs pulls the floppy tissue across the airway to partially occlude it. This partial obstruction of the airway generates the whistling sound.
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Epiglottitis management
Epiglottitis is an emergency and there is an immediate risk of the airway closing. A key point that is often talked about with epiglottitis is the importance of not distressing the patient, as this could prompt closure of the airway. If you see a child with suspected epiglottitis, leave them well alone and in their comfort zone. Don’t examine them and don’t make them upset. The most important thing is to alert the most senior paediatrician and anaesthetist available.
Management of epiglottis centres around ensuring the airway is secure. Most patients do not require intubation, however there is an ongoing risk of sudden upper airway closure, so preparations need to be made to perform intubation at any time. Intubation is often difficult and needs to be performed in a controlled environment with facilities available to do a tracheostomy (intubating through the neck) if the airway completely closes. When patients are intubated they are transferred to an intensive care unit.
Additional treatment once the airway is secure:
```
IV antibiotics (e.g. ceftriaxone)
Steroids (i.e. dexamethasone)
```
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Laryngomalacia management
The problem resolves as the larynx matures and grows and is better able to support itself, preventing it from flopping over the airway. Usually, no interventions are required and the child is left to grow out of the condition.
Rarely tracheostomy may be necessary. This involves inserting a tube through the front of the neck into the trachea, bypassing the larynx. Surgery is also an option to alter the tissue in the larynx and improve the symptoms.
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Whooping cough
Whooping cough is an upper respiratory tract infection caused by Bordetella pertussis (a gram-negative bacteria). It is called “whooping cough” because the coughing fits are so severe that the child is unable to take in any air between coughs and subsequently makes a loud whooping sound as they forcefully suck in air after the coughing finishes.
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Whooping cough cause
Bordatella pertussis a gram negative bacteria
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Whooping cough timeline
More severe coughing fits start after a week or more. These involve sudden and recurring attacks of coughing with cough free periods in between. This is described as a paroxysmal cough. Coughing fits are severe and keep building until the patient is completely out of breath. Patient typically produces a large, loud inspiratory whoop when the coughing ends
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Whooping cough presentation
Pertussis typically starts with mild coryzal symptoms, a low-grade fever and possibly a mild dry cough.
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Whooping cough investigation (2)
A nasopharyngeal or nasal swab with PCR testing or bacterial culture can confirm the diagnosis within 2 to 3 weeks of the onset of symptoms.
Where the cough has been present for more than 2 weeks patients can be tested for the anti-pertussis toxin immunoglobulin G. This is tested for in the oral fluid of children aged 5 to 16 and in the blood of those aged over 17.
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Whooping cough management (3)
Mainly supportive care
Antibiotics (azithromycin, erythromycin, clarithromycin)
Close contacts given prophylaxis antibiotics
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Chronic lung disease of prematurity known as?
Bronchopulmonary dysplasia
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When does CLDP occur?
Typically in babies born before 28 weeks gestation
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Presentation CLDP (6)
```
Respiratory distress
Low oxygen saturations
Increased work of breathing
Poor feeding and weight gain
Crackles and wheezes on chest auscultation
Increased susceptibility to infection
```
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CLDP investigation (1)
Diagnosis is made based on chest xray changes and when the infant requires oxygen therapy after they reach 36 weeks gestational age.
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CLDP prevention (4)
Giving corticosteroids (e.g. betamethasone) to mothers that show signs of premature labour at less than 36 weeks gestation can help speed up the development of the fetal lungs before birth and reduce the risk of CLDP.
Once the neonate is born the risk of CLDP can be reduced by:
• Using CPAP rather than intubation and ventilation when possible
• Using caffeine to stimulate the respiratory effort
• Not over-oxygenating with supplementary oxygen
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CLDP management (2)
A formal sleep study to assess their oxygen saturations during sleep supports the diagnosis and guides management. Babies may be discharged from the neonatal unit on a low dose of oxygen to continue at home, for example 0.01 litres per minute via nasal cannula. They are followed up to wean the oxygen level over the first year of life.
Babies with CLDP require protection against respiratory syncytial virus (RSV) to reduce the risk and severity of bronchiolitis. This involves monthly injections of a monoclonal antibody against the virus called palivizumab. This is very expensive (around £500 per injection) so is reserved for babies meeting certain criteria.
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CF?
Cystic fibrosis (CF) is an autosomal recessive genetic condition affecting mucus glands. It is caused by a genetic mutation of the cystic fibrosis transmembrane conductance regulatory gene on chromosome 7.
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What is the most common gene mutation causing CF
There are many variants of this mutation, the most common is the delta-F508 mutation. This gene codes for cellular channels, particularly a type of chloride channel
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Epidemiology of CF
Around 1 in 25 are carriers of the mutation and 1 in 2500 children have CF.
