Format 2016: tachypnoea in a well baby: what to do next?

Tachypnoea in a well baby: what to do next?

Attilio BonerUniversity ofVerona, Italy

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IntroductionPhysiology of breathingWhat is tachypnoea?Is the baby unwell?Is the examination normal? Immediate clinic investigations:

SaO2, Chest X-rayFurther investigationsPotential causes of tachypnoea when

the diagnosis is not immediately obvious

OutcomeSummary & Conclusions

Tachypnea and cyanosis in the newborn are frequently encountered problems in the nursery.

The incidence of respiratory distress in newborns ranges from 2.9% to 7.6%.

4.3% of newborns may require supplemental oxygen therapy.

In the nursery

•Hjalmarson O. Epidemiology and classification of acute neonatal respiratory disorders. Acta Paediatr Scand 1981;70:773– 83.•Hjalmarson O. Epidemiology of neonatal disorders of respiration. Int J Technol Assess Health Care 1991;7(Suppl):9–16.•Kumar A, Bhat V. Epidemiology of respiratory distress of newborns. Indian J Pediatr 1996;63:93– 8.

Chest radiographs in a premature infant with respiratory distress syndrome before and

after surfactant treatment.

Respiratory plasticity following intermittent hypoxia: developmental interactions.

Gozal E, J Appl Physiol 2001;90(5):1995-9.

Schematic diagram showing the potential interactions between intermittent hypoxia and its characteristics and the hypoxic ventilatory response pathwaysin mammals.

Intermittent hypoxia can affect both peripheral chemoreceptor (PC) responses as well as thoseof centrally located neurons (CNS).Such interactions will be modulated to a greater or lesser extent by the developmental stage of the mammals. Such global relationships will result in phenotypic changes of ventilation (V˙ E), metabolism (V˙ O), as well as arousal, behavior, learning, and stress responses.In addition, such modifications in phenotypewill depend on alterations in expression and function of neurotransmitters and their receptors, intracellular signaling molecules, transcription factors, and genes.

++++

++++

++++ peripheral chemoreceptor



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IntroductionPhysiology of breathing What is tachypnoea?Is the baby unwell?Is the examination normal? Immediate clinic investigations:




at birth huge physiological changes

breathing begins in utero as early as 11 weeks

•this is in contrast to human adults with well developed ventilatory control system who demonstrate sustained hyperventilation in response to hypoxia.

•up to 6 months of age hypoxic ventilatory response in term infants shows considerable variability with respect to ventilation and arousal responses with an initial period of augmentation in ventilation followed by a sustained reduction in ventilation similar to or below normoxic ventilation.

ventilatory control system

MacLean JE, Paediatr Respir Rev. 2015 Aug 14.

Physiology of breathing

Minute Ventilation in InfancyMinute ventilation (V) = respiratory rate (RR) X tidal volume (VT)

is related to metabolic rate.

to respond to increased metabolic demand, minute ventilation can be

increased by: •increasing the RR,

•increasing the VT,

•or both.

.

Minute Ventilation in InfancyMinute ventilation (V) = respiratory rate (RR) X tidal volume (VT)

is related to metabolic rate.

to respond to increased metabolic demand, minute ventilation can be

increased by: •increasing the RR,

•increasing the VT,

•or both.

.

In the newborn and young child, increasing the respiratory rate (rather than tidal volume) is the most energy-efficient

strategy to cope with higher ventilatory needs.

Ross KR. Clin Chest Med. 2014;35:457.

A study of breathing pattern and ventilation in newborn infants and adult subjects.

Al-Hathlol K, Acta Paediatr 2000;89:1420–5.

Box and Whisker plot of ventilatory variable -minute ventilation (VE) (L/Kg/min), -respiratory frequency (f) (n°/min), -tidal volume (VT) (mL/Kg/min),

Instantaneous ventilation decreased from preterm to adult subjects primarily due toa decrease in frequency .

Coefficients of variation always decreasedwith age.

Horizontal bars in the boxes reflect median value. Differences between groups are all significant at p < 0.05.

6-7.5 mL/kg



Breath duration and its components . Duration of the average breath increased with postnatal age and this was related to increases both in:Ti (inspiratory time in seconds) and Te (espiratory time in seconds) .

Note the high coefficient of variation for Te in preterm infants. The high variability in Te early in life represents an effort to maintain lung volume through increased post-inspiratory diaphragmatic activity and increased upper airway resistance in an attempt to avoid collapse due to poor chest wall recoil.



The “effective” respiratory timing (Ti/Ttot) is low in preterm and increases towards adulthood.

The changes in respiratory frequency with age relatedto adjustments in Ti and Te, Ti increasing almost threefold from preterm to adulthood and Te increasing only twofold.

In the preterm infant Ti occupied only 34% of the total breath duration and in adults it represented 45%

Diagram of the shape of a breath

45%34%

1:21:1.5

1:1Ti:Te

Frequency of obstructive and mixed sleep apneas in 1,023 infants. Kato I, Sleep. 2000;23(4):487-92.

To collect normative data on the frequency of obstructive and mixed sleep apneas in healthy infants born at term.

1023 infants (2-27 weeks) recorded during one night in a sleep laboratory

Apnea defined as ≥ 3 sec.

50 –

40 –

30 –

20 –

10 –

0

% of infants with

ObstructiveApneas (OAs)

Central Apneas (CAs)

40.0%

22.3%*

15.8% had both

Oas and CAs

Frequency of obstructive and mixed sleep apneas in 1,023 infants. Kato I, Sleep. 2000;23(4):487-92.

To collect normative data on the frequency of obstructive and mixed sleep apneas in healthy infants born at term.

1023 infants (2-27 weeks) recorded during one night in a sleep laboratory

Apnea defined as ≥ 3 sec.

50 –

40 –

30 –

20 –

10 –

0

% of infants with

ObstructiveApneas (OAs)

Central Apneas (CAs)

40.0%

22.3%*

15.8% had both

Oas and CAs

Obstructive apneas lasting >

5-10 seconds were more frequent in

the 2-7 week age

group than in the later ages (p<0.001

for both)

Physiology of breathing

ventilatory control system

3-6 sec 3-6 sec 3-6 sec

≈ 20 sec ≈ 20 sec

Periodic breathing is a pattern of breathing characterized by recurrent central apnoea (< 6sec, usually 3 sec) that occur in groups of 3 or more, interrupted by breathing efforts (for 20 sec) which may be seen in both preterm and term infants after 48 hours of age.

Periodic breathing is more commonduring sleep, and is usually seen from1 week to 2 months of age; it tends to disappearby 6 months and is of no consequence and is thought to reflect a developmental instability in the ventilatory control system.

Longitudinal assessment of hemoglobin oxygen saturation in healthy infants during the first 6

months of age. Collaborative Home Infant Monitoring Evaluation (CHIME) Study Group.

Hunt CE, J Pediatr 1999;135:580–6. 64 infants from 2 to 25 weeks

Median baseline SaO2 for each postnatal week at 2 to 25 weeks of age.

Variations inSpO2 occurring with increasing age are not significant.

59% of infants had at least one epoch with a baseline <90%

saturation median was 97.9% with the 10th percentile at 95.2%

Longitudinal assessment of hemoglobin oxygen saturation in healthy infants during the first 6

months of age. Collaborative Home Infant Monitoring Evaluation (CHIME) Study Group.

Hunt CE, J Pediatr 1999;135:580–6.

Number of seconds with SaO2 <90% during acute decrease, expressed per hour bypresence of periodic breathing or not and by week of age.

more frequent during active or REM sleep

number of seconds per hour with saturation < 90%

Rapid eye movement sleep characterized by quick, random movements of the eyes

and low muscle tone



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Respiratory rate in 1st year of life, awake (solid line) and asleep (dashed line) showing 5th, 50th and

95th centiles. Rusconi F, Pediatrics 1994;94:350–5.The normal respiratory

rategradually decreases

over the 1st year

There is no gender

differenceand

the rate is higher in awake babies

Respiratory rate in 1st year of life, awake (solid line) and asleep (dashed line) showing 5th, 50th and

95th centiles. Rusconi F, Pediatrics 1994;94:350–5.The normal respiratory

rategradually decreases

over the 1st year

There is no gender

differenceand

the rate is higher in awake babies

In the first months of life

tachypnea is defined as a respiratory rate

> 60 breaths per minute.

Measuring the respiratory rate is not always easy, especially if the baby is moving or crying; both these change the rate, and the state of the baby (especially awake vs asleep) should be recorded alongside the rate.

It is easier to use a stethoscope to listen for breaths rather than simply watching the baby’s chest. Auscultation usually gives a higher rate, presumably due to missed breaths from observation alone.

The rate needs to be measured over a full minute(or the sum of two sets of 30 s), and will need to be repeated a few times if it is variable.

IS THE BABY TACHYPNOEIC?

Not x230s+30s

The respiratory rate when awake did not correlate with the severity of a baby's illness or the presence of serious lower respiratory tract infections.

Respiratory rate and severity of illness in babies under 6 months old. Morley CJ, Arch Dis Child.

1990;65:834-7.

RR No kwith illness

Respiratory rate in babies under 6 months of age.

Counted by 2 observers in 1007 babies of whom 709 were seen when presenting to hospital for assessment of an acute illness, and 298 on a random basis at home.

60 61 59 58

Respiratory rate of awake babies compared with assessor's impression of

the severity of illness

Respiratory rate and severity of illness in babies under 6 months old. Morley CJ, Arch Dis Child.

1990;65:834-7.

The respiratory rate (breaths per minute) thresholds are set at:

- 60 for infants < 2 months of age, - 50 for infants from 2 to 12 months, - 40 for children aged 1 to 5 years.

WHO recommends a repeat respiratory rate count for infants under 2 months of age when the initial count is 60 or higher.

Respiratory rate and pneumonia in infancyBerman S, Arch Dis Child. 1991;66:81-4

The respiratory rate (breaths per minute) thresholds are set at:

- 60 for infants < 2 months of age, - 50 for infants from 2 to 12 months, - 40 for children aged 1 to 5 years.

WHO recommends a repeat respiratory rate count for infants under 2 months of age when the initial count is 60 or higher.

Respiratory rate and pneumonia in infancyBerman S, Arch Dis Child. 1991;66:81-4

a repeat count 45 to 60 minutes later will be less than the threshold in more than two thirds of the patients with an upper respiratory infection

in contrast to patients with lower respiratory infection who will usually maintain a raised respiratory rate.

=

Although respiratory rate is a useful predictor of lower respiratory infection in young infants, it does not correlate well with hypoxia.

The presence of subcostal retractions is a more useful predictor of hypoxia expecially if associated with nasal flaring, refusal to eat, and abdominal distention.Berman S, Pediatr Emerg Care. 1990;6(3):179-82.Berman S, Arch Dis Child 1991;66:81–4.

Meaning of Respiratory Rate

RR ≠ SaO2

≈ SaO2



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IS THE BABY UNWELL?

Certain symptoms elicited from the history at this stage are red flags for concern of a significant underlying condition:

▸ Persistent cough▸ Apnoeic episodes▸ Noisy breathing▸ Poor feeding▸ Vomiting▸ Choking when drinking

Apnea in infants is most commonly defined as a pause in

breathing for at least 20 seconds, or a

shorter pause that is associated with bradycardia or

oxygen desaturation.Uliel S, Chest 2004;125:872–8.

X X X X X X X X X X



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IS THE EXAMINATION NORMAL?

The child’s weight, height and head circumference will give an indication of faltering growth which may be secondary to tachypnoea or an underlying condition.

Underlying conditions: Weight Lenght(Height)

Head Circumference

Malnutrition, loss of calories, inability to use calories peripheraly

+++ Reduced

Not reduced Normal

Short stature, heart or renal diseases, scheletal dysplasias

+ Not much reduced

+++ Reduced Normal/enlarged

CNS abnormalities, chromosomal defects, in utero/perinatal insuts

+++ Reduced

+++ Reduced +++ Reduced

▸ Respiratory distress▸ Cyanosis, paleness▸ Cardiac murmur▸ Abnormal femoral pulses▸ Hepatomegaly▸ Hypotonia

Clinical examination is important, with some red flag warning signs:


intercostal and subcostal recession, tracheal tug, use of accessory muscles, grunting, nasal flaring.

Some well babies with tachypnoea

have a degree of recession as the only other clinical sign.

Balfour-Lynn IM, Arch Dis Child. 2015;100(8):722-7.

Obviously the presence of crackles, wheeze and stridor is important for the diagnosis.

Paradoxical breathing, an inward movement of the chest wall during inspiration, often with a seesaw thoracoabdominal, motion must be looked for (neuromuscular disease, diaphragmatic abnormality, upper airway obstruction).


normal

The shape of the thorax is checked to ensure normal dimensions:

very small in asphyxiating thoracic dystrophy,

bellshaped in pulmonary hypoplasia.


The shape of the thorax is checked to ensure normal dimensions:

very small in asphyxiating thoracic dystrophy,

bellshaped in pulmonary hypoplasia.


Barrel-shaped chest is frequently seen in post-term

infants who have meconium aspiration

syndrome

The presence of persistent rhinitis in infancy should make one consider primary ciliary dyskinesia.


The patency of the nose must be examined to exclude choanal stenosis or unilateral or bilateral atresia holding the stethoscope over the nostrils (it may be necessary to pass a nasogastric tube down both sides).

choanal atresia

Cardiac apex may be visibly displaced (> 5° intercostal space) if there is cardiomegaly.

Precordial palpation may reveal aright-sided impulse in Scimitar syndrome,or complex forms of congenital heartdisease associated with atrial isomerism(visceral heterotaxy or a mirror imagearrangement in primary ciliary dyskinesia).


Examination focused specifically on the cardiovascular system is also important and often neglected.

Scimitar syndrome, characterized by anomalous venous return from the right lung (to the systemic venous drainage, rather than directly to the left atrium

12345


A prominent precordial impulse is animportant sign of cardiovascular diseasewith pressure or volume overload of theheart (valvular diseases, septal defects…).

Femoral pulses which are weak ordifficult to feel (coarctation of the aorta), orgenerally weak pulses (myocarditis, dilatedcardiomyopathy, severe aortic stenosis orother forms of left heart obstruction) can be important signs.

Liver enlargement is usually a manifestation of heart failure, but can be palpable if it is displaced by overinflated lungs.

These include: •holosystolic murmur (odds ratio [OR] of pathologic murmur = 54), •grade 3 (heard easily) or higher (OR = 4.8), •harsh quality (OR = 2.4), •an abnormal S2 (OR = 4.1), •maximal intensity at the upper left sternal border (OR = 4.2), •systolic click (OR = 8.3), •diastolic murmur, or increased murmur intensity with standing. •decrease or lack of change in the murmur intensity with passive leg elevation (likelihood ratio [LR] = 8.0) or when the child moves from standing to squatting (LR = 4.5) increases the likelihood of hypertrophic cardiomyopathy

Certain characteristics of the murmur may be considered red flags, prompting stronger

consideration for structural heart disease

Frommelt MA. Differential diagnosis and approach to a heart murmur in term infants. Pediatr Clin North Am. 2004;51(4):1023–1032

pulmonary valve


Cyanosis would be visible if the deoxygenated hemoglobin content is > 3 g% (3 g per 100 mL).

If cyanosis is present throughout the body, including the mucous membranes and tongue, it is called central cyanosis.

If cyanosis is limited to the extremities, it is called peripheral cyanosis, also known as acrocyanosis.

1) exposure to cold,2) polycythemia.

in conditions in which the infant is exposed to a cold environment,

it could also be the presenting sign of serious conditions such as:

1) sepsis 2) hypoglycemia 3) hypoplastic left-heart syndrome (decreased peripheral perfusion)


peripheral cyanosis is seen:

Peripheral cyanosis should not be ignored unless other conditions have been ruled out.

hence diffuse mottled, bluish-gray appearance of this infant's skin

suggestive of systemic poor perfusion

Differential Cyanosis: another form of cyanosis

1) the upper part of the body remains

pink and lower part of the body remains

cyanotic.

right-to left shunt from the pulmonary artery to the

descending aorta through the patent ductus arteriosus (PDA) such as in hypoplastic

left heart syndrome or severe pulmonary

hypertension

2) the upper part of the body remains cyanotic while the lower part of the body remains pink.

transposition of the great vessels with pulmonary hypertension and shunt through PDA,

total anomalous pulmonary venous drainage above thediaphragm with shunt through PDA (higher oxygen content in the right ventricular blood).

Differential Cyanosis: another form of cyanosis

1) the upper part of the body remains

pink and lower part of the body remains

cyanotic.

right-to left shunt from the pulmonary artery to the

descending aorta through the patent ductus arteriosus (PDA) such as in hypoplastic

left heart syndrome or severe pulmonary

hypertension

2) the upper part of the body remains cyanotic while the lower part of the body remains pink.

transposition of the great vessels with pulmonary hypertension and shunt through PDA,

total anomalous pulmonary venous drainage above thediaphragm with shunt through PDA (higher oxygen content in the right ventricular blood).

Thus whenever tachypnoea has a cardiovascular cause, even without a heart

murmur there is usually a clinical pointer to a cardiac anomaly.

Conditions that can give rise to arterial oxygen desaturation and cyanosis:

1) Hypoventilation (tachipnea alone is not a good marker of hypoxia)

2) Significant right-to-left intracardiac or intrapulmonary shunting

3) Ventilation perfusion unevenness

4) Diffusion impairment (very rare)

5) Inadequate transport of oxygen by the hemoglobin (mutant hemoglobins).


Sasidharan P. Pediatr Clin North Am. 2004;51(4):999-1021

Conditions that can give rise to arterial oxygen desaturation and cyanosis:

1) Hypoventilation (tachipnea alone is not a good marker of hypoxia)

2) Significant right-to-left intracardiac or intrapulmonary shunting

3) Ventilation perfusion unevenness

4) Diffusion impairment (very rare)

5) Inadequate transport of oxygen by the hemoglobin (mutant hemoglobins).


Sasidharan P. Pediatr Clin North Am. 2004;51(4):999-1021

The net result of an inadequate oxygen delivery to the tissues leading to hypoxia is

increased production of hydrogen ions and lactic acid,

giving rise to metabolic acidosis.

The detection of metabolic acidosis (pH <7.35, PaCO2 <35, HCO3- < 22 mEq/L)

along with cyanosis in an infant usually indicates a compromised state

and requires immediate attention.


Abdominal examination is done to exclude an enlarged liver or spleen, or an abdominal mass.

A basic neurological examination is done, particularly for hypotonia which may indicate a neuromuscular disorder.

Always listen over the skull and particularly the occiput for the murmur of a cerebral arteriovenous fistula, whose only clinical manifestation might be tachypnoea. Iizuka Y, Neuroradiol J. 2011;24(5):772-8

Algorithm for managementof a baby with tachypnoea. CXR, chest radiograph; SpO2, oxygen saturation.

Balfour-Lynn IM, Arch Dis Child. 2015;100:722-7.

SaO2 < 95%

it is possible to wait for 4 weeks



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Oxygen saturation (SpO2) reference values

Healthy infants aged < 1 year

The median baseline saturation in healthy term infants during thefirst year of life is 97–98%. In only 5% of healthy infants is the SpO2 < 90% for > 4% of the time. Healthy children aged >1 year

The median baseline SpO2 in healthy children >1 year old is 98%with a 5th centile of 96–97%.

A healthy child aged 5–11 years spends no more than 5% of thetime below a SpO2 of 94% while asleep.Balfour-Lynn IM, Thorax 2009;64(Suppl 2):ii1–26.

Newborn pulse oximetry screening is not just for heart defects.

Meberg A. Acta Paediatr. 2015 Sep;104(9):856-7.

A Norwegian population-based (n=50.008) prospective multicenter study of postductal (foot) arterial oxygen study on the first day of life reported a SpO2 < 95% in 0.65% of the infants and 41% of these were, in fact, potentially severe extra-cardiac disorders, such as:

•systemic infections – including group B streptococcal septicaemia – •amniotic fluid aspiration, •pulmonary hypertension and•pneumothorax.Meberg A, J Pediatr 2008;152:761–5.

(healthy infants)

(severe polycythemia)

Oxygen saturation (SpO2) is the most important initial investigation.

If the SpO2 is significantly low (<85%) both in room air and 100% oxygen, one should consider a hyperoxia test. Sasidharan P. Pediatr Clin North Am 2004;51:999–1021

a formal test is carried out with arterial blood gases (PaO2) or transcutaneous oxygen monitoring (TcPO2) from the right arm (preductal) after administration of 100% oxygen for 5–10 min.

if supplemental oxygen does not improve the partial pressure of oxygen in arterial blood (PaO2), cyanotic congenital heart disease or some form of right to left shunting must be considered with an immediate cardiology assessment.

Oxygen saturation (SpO2) is the most important initial investigation.

A useful guide to evaluate the response to hyperoxia test:

▸ PaO2> 33 kPa (247.5 mm3)—excludes cyanotic heart disease (neuromuscolar-neurologic disease more likely)

▸ PaO2> 26 kPa (195 mm3)—cyanotic heart disease very unlikely (pulmonology disease more likely)

▸ PaO2< 13 kPa (97.5 mm3)—cyanotic heart disease extremely likely

(1 kPa = 7.500617 mmHg; 1 mmHg = 0.133322 kPa)

Balfour-Lynn IM, Arch Dis Child. 2015;100(8):722-7.

Chest Radiography

Chest Radiography

The expansion of lungs (lung volume) on both sides should be checked.

Normal inspiratory films should have 8 intercostal spaces of lung fields on both sides.

12

34

56

7

8

12

345678

Chest Radiography

The locations of stomach, liver, and heart should be determined to rule out dextrocardia and situs inversus.

stomach

Chest Radiography

Increased pulmonary vascular markings and pulmonary congestion are indicative of a left-to-right shunt.

Decreased pulmonary vascular markings (oligemic lung fields) are generally indicative of pulmonary stenosis or pulmonary atresia with inadequate ductal shunting and occasionally persistent pulmonary hypertension of the newborn (PPHN).

Ventricular septal defect

Chest Radiography

Red arrow points to end of orogastric tube which is blocked from entering the distal esophagus by the patient's esophageal atresia.

Note the lack of gas in the abdomenindicating a fistulous tract does not connect the trachea to the distal esophagus

With esophageal atresia and no fistula, no air enters GI tract and abdomen is airless

Stomach should have air in it 15 minutes after birth normally.

Chest Radiography

Heart size, shape and position may indicate cardiac disease.

The integrity of the diaphragm is checked (eventration, hernia, paralysis).

Chest shape and size are assessed (eg, bell-shaped in pulmonary hypoplasia),

as well as the ribs themselves,which may have the classic abnormalitiesof severe neonatal rickets, or be very thin (gracile) in neuromuscular disease.

The cardiothoracic ratio aids in the detection of cardiomegaly, is

measured on a PA chest x-ray, and is the ratio of:

maximal horizontal cardiac diametermaximal horizontal thoracic diameter (inner edge of ribs / edge of pleura)

A normal measurement should be less than 0.5

normal

enlarged

<0.5

Chest Radiography




as well as the ribs themselves,which may have the classic abnormalitiesof severe neonatal rickets, or be very thin (gracile) in neuromuscular disease.

eventration

hernia

paralysis

Chest Radiography




as well as the ribs themselves,which may have the classic abnormalitiesof severe neonatal rickets, or be very thin in neuromuscular disease.

pulmonary hypoplasia

rachitic rosary

Chest Radiography





pulmonary hypoplasia

neuromuscular disease

Chest Radiography





Additionally, as with any unexplained

symptom in children, non-accidental injury

must be considered and the

ribs checked for fractures.

Oxygen saturation & Chest Radiography

At this stage, a well baby with tachypnoea(with or without some recession),

who has a normal SpO2 and chest radiograph, can leave clinic and go home

with follow-up in 4 weeks, or sooner if the clinical picture changes.

normal



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Generally the babies remain well and gradually the degree of tachypnoea reduces with time.

However if there is no improvement, and especially if the degree of respiratory distress increases, further investigations become necessary.

FURTHER INVESTIGATIONS

Red flag initial investigations:

▸ Hypoxia (oxygen saturation (SpO2) ≤ 94%)

▸ Abnormal chest radiograph


cardiac failure,

sepsis,

asphyxia,

metabolic disorders.

closure of the ductus arteriosus in an infant who has ductal-dependent cardiac lesion will lead to shock and severe metabolic acidosis, with cyanosis and respiratory distress.

Arterial blood gases help in determining the oxygenation,

ventilation, and acid-base status.

if significant metabolic acidosis

pH < 7.35HCO3- (mEq/L) < 22


EKG is an important test, but of limited value except in certain specific conditions. Normally, there is right-ventricular predominance in the newborn, and many cases of cyanotic congenital heart disease (CHD) will havesimilar findings.

Echocardiogram is the gold standard in the diagnosis of congenital cardiac lesions and pulmonary hypertension.


the second wave of investigations may well include the following:

Dual probe 24-h pH study (salivary pepsin?).

Swallowing assessment —clinical evaluation and videofluoroscopic swallowing study.

Ultrasound or fluoroscopic screening of the diaphragms.

CT chest scan —this can be done without the need for sedation in most infants, using the ‘feed and wrap’ technique. Sury MR, Clin Radiol 2005;60:731–41. There is no need for a contrast-enhanced scan at this stage.

submucous clefting

'Feed and wrap' or sedate and immobilise for neonatal brain MRI?

Ibrahim T, Arch Dis Child Fetal Neonatal Ed. 2015;100(5):F465-6.

A sedated infant still asleep post MRI within the Med-Vac immobiliser.

chloral hydrate sedation(50 mg/kg single dose) combined with Med-Vac immobilizationhas safely achieved a 100% success rate forcompleted MRI with good-quality clinicaland research imaging, and has proved farsuperior to the ‘feed and wrap’ method.



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SaO2, Chest X-rayFurther investigationsPotential causes of tachypnoea

when the diagnosis is not immediately obvious


POTENTIAL CAUSES OF TACHYPNOEAWHEN THE DIAGNOSIS IS NOT IMMEDIATELY OBVIOUS

•small thorax of Jeune asphyxiating thoracic dystrophy, •bell-shaped chest from pulmonary hypoplasia, •hypotonia associated with neurological or neuromuscular disease, •stridor due to upper airway obstruction •severe neonatal rickets.

Often the tachypnoea is just one of several

signs in a clearly unwell child

•a metabolic acidosis•bacterial sepsis; or •significant pain, for example, from a volvulus.

In some children, the cause becomes

more clear from the history

•narcotic withdrawal •postbirth asphyxia.

In some, it may be

determinedon first

examination

POTENTIAL CAUSES OF TACHYPNOEAWHEN THE DIAGNOSIS IS NOT IMMEDIATELY OBVIOUS

Respiratory and upper airway

InfectionCystic fibrosisInterstitial lung diseaseCongenital thoracic malformationsPulmonary hypoplasiaCongenital diaphragmatic herniaDiaphragmatic weaknessH-type tracheo-oesophageal fistulaNasal obstruction

Pulmonary tuberculosis has been described in children under 1 year, with tachypnoea the predominant sign. Arikan-Ayyildiz Z, Turk J Pediatr 2011;53:250–4.

Infection.

It is likely the child would have other symptoms and signs

fever cough shallow breathing

nevertheless, low gradeor chronic infection must be considered.

a nasopharyngeal aspirate for respiratory viruses a cough swab for bacterial culture, a white cell count, C reactive protein, procalcitonin

may be helpful

Chest radiograph shows cavity within consolidation in the right lobe.

Most babies are symptom-free from the respiratory perspective, the majority have suboptimal weight gain, often with abnormal stools.

Infants can present with tachypnoea, recurrent cough and sometimeswheeze, but our experience is that it is most unusual for tachypnoea to be the sole symptom in a baby with CF.

A sweat test must be considered.

Cystic fibrosis

newborn screening babies are diagnosed with cystic fibrosis (CF) at around 3–4 weeks of

agehowever screening is not infallible

Interstitial lung disease

often associated with:•recession,•crackles •and sometime hypoxia.

a heterogeneousgroup of rare

diseases

crackles, recession, hypoxaemia, eventualy failure to thrive.

most often accompanied by:

Kuo CS, Curr Opin Pediatr 2014;26:320

in some infants , tachypnoea is the only obvious symptom, and the severity of symptoms and signs

varies.

Neuroendocrine cell hyperplasia, previously known

as persistent tachypnoea of

infancyDeterding RR, Pediatr Pulmonol 2005;40:157–65

European protocols for the diagnosis and initial treatment of interstitial lung disease in children.

Bush A, Thorax. 2015;70(11):1078-84.THE STARTING POINT: WHEN TO SUSPECTCHILD—TYPICAL PRESENTATIONS Shortly after birthThe earliest presentation of chILD is shortly after birth, with unexplained respiratory distress in a term baby. This frequently and rapidly proceeds to intubation and ventilation, with relentlessly progressive respiratory failure leading to death orlung transplantation, if the latter is available.

First 2 years of lifeLater presentations of chILD are very non-specific and symptoms in descending order of frequency are: fast breathing, failure to thrive, typically dry cough, and wheeze in 25% of cases in the absence of respiratory tract infection.

XX X X X

Staging the severity of childhood interstitial lung disease (chILD)

Pediatric interstitial lung disease revisited.Fan LL, Pediatr Pulmonol 2004;38:369–78.

(awake)


Bush A, Thorax. 2015;70(11):1078-84.

Proposed flow chart for investigating interstitial lung disease in children (chILD)

If the child is well and stable, progress to the moreinvasive investigations may not be indicated.


Bush A, Thorax. 2015;70(11):1078-84.

SURGICAL LUNG BIOPSYprocedure must only be undertaken by an experienced surgeon, who is confident of obtaining adequate biopsies (at least 10×10×10 mm); a very superficial biopsy, which does not contain distal airways, may result in diagnostic error.

40-month-old girl with typical appearance of neuroendocrine cell hyperplasia of infancy

Brody AS, AJR Am J Roentgenol. 2010;194:238-44Inspiratory high-resolution CT scans show sharply defined areas of ground-glass

opacification along mediastinal borders, peripherally, and most prominently in right middle lobe and lingula (asterisks, C)

Expiratory high-resolution CT scans show only mild increase in attenuation in all areas of lung, consistent with air trapping involving both areas with ground-glass opacification and areas with normal attenuation

* *

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Surfactant protein B deficiency is lethal in neonates so is unlikely to present with just tachypnoea.

Inherited surfactant protein C deficiency, •Tachypnoea and other signs of respiratory distress are likely to be present. Thouvenin G, Arch Dis Child 2010;95:449–54.

•A chest CT scan can be highly suggestive, although diagnostic certainty may require a lung biopsy, and gene mutation studies.

Interstitial lung disease

chest radiograph and computed tomography scan of a patient at 18 months showing diffuse ground glass pattern and

interstitial thickening.

Congenital Thoracic Malformations

Cystic congenital thoracic malformations

usually asymptomatic

diagnosed antenatally during fetal ultrasound scanning

•Congenital cystic adenomatoid malformation (CCAM) is usually observed in neonates because of respiratory distress and may occasionally be observed in older children or adults with recurrent infection. •This malformation consists of adenomatoid proliferation of bronchioles that form cysts instead of normal alveoli:

type 1 CPAM are one or more large air-filled cystic lesions

Type 2 CPAM usually consists of an air-filled multicystic mass or focal area of consolidations

a) Chest radiograph shows an area of hyperlucency (arrow) in the right lower lobe. b) CT scan demonstrates the presence of several small cysts (arrow) in the right lower lobe.

CPAM = Congenital pulmonary airway malformation

Congenital Thoracic Malformations

in some cases tachypnoea does not develop for 1–4 months and although usually obvious on a plain chest radiograph, the lesion may be only apparent on a CT scan. Rusakow LS, Pediatr Pulmonol 2001;32:246–9.

Congenital Lobar Emphysema

neonatal respiratory distress present at birth or within the first 48 h,

a developmental anomaly of the lower respiratory tract that is characterized by hyperinflation of one or more of the pulmonary lobes

Radiographically occult congenital lobar emphysema presenting as unexplained neonatal

tachypneaRusakow LS, Pediatr Pulmonol 2001;32:246-9A neonate with tachypnea of unclear etiology who was diagnosed with

congenital lobar emphysema (CLE) by chest computed tomography scan, despite a plain chest radiograph that did not suggest the

diagnosis.

Chest CT scan image demonstrating hyperinflated (hyperlucent) left upper

lobe anterior to normal-appearing superior segment of left lower lobe; right

lung also appears normal

Chest radiograph of 8-day-old boy demonstrating

hyperinflation without focal abnormalities

Congenital Lobar Emphysema usually presents in infancy with dyspnea, wheezing, cough, tachypnea, cyanosis during feeding and crying, and intercostal retractions. Rusakow LS, Pediatr Pulmonol 2001;32:246-9

Classically, 3 clinical patterns have been described:

1) findings develop within the first 2 days of life; 2) findings or signs develop between 1-4 months of life; 3) a rare, fulminant form, associated with severe cardiorespiratory involvement, which may lead to death within hours.

Leape LL, Pediatrics 1964;34:246-255

Congenital Lobar Emphysema: Patterns of Presentation

The etiologies for CLE, are thought to be multiple, and may involve:

1) partial bronchial obstruction due to extrinsic compression, 2) intraluminal obstruction,

3) intrinsic bronchial abnormality such as bronchomalacia,

4) a primary alveolar abnormality.

Leape LL, Pediatrics 1964;34:246-255

all leading to a “check-valve” effect

Congenital Lobar Emphysema: Etiologies

Histopathology of congenital lobar emphysema with marked overdistention of all alveoli.

Pulmonary Hypoplasia

Severe oligohydramnios

Congenital Diaphragmatic Hernia,

Ebstein’s malformation of the tricuspid valve(reduced blood flow to he lungs)

It is rarely an isolated phenomenon (primary).Aiton NR, BMJ 1996;312:1149–50.

more commonly is secondary and

associated with disorders of lung growth


Patients may present in early infancy, and the severity depends

on the degree of hypoplasia;

persistent tachypnoea and

breathlessness with activity/exercise

when the hypoplasia is not too severe

when unilateral

the thorax is asymmetrical, reduced air entry and underexpansion on that side.

diffuse haziness (nebulosità) of the right hemithorax (arrow), slight deviation of the trachea

and heart to the right, and poor differentiation of the right heart

border.







when unilateral




border.

Confirmation can usually be made with a chest radiograph or a chest CT scan.

With normal radiology, infant lung function testing may be necessary which would indicate reduced lung volumes and reduced functional

residual capacity.

Reference values for residual volume, functional residual capacity and total lung capacity. ATS Workshop on Lung

Volume Measurements. Official Statement of The European Respiratory Society.

Stocks J, Quanjer PH. Eur Respir J. 1995 ;8(3):492-506.







when unilateral




border.

Primary pulmonary hypoplasia, however, is thought

to be very rare and published reports are few. Swischuk LE. JPediatr 1979;95:573-8.

Boylan P. Irishj Med Sci 1977;146:179-80.

There is a large discrepancy, however, with the incidence reported in one post mortem series:

pulmonary hypoplasia was the commonest single abnormality present in 15-20%

of early neonatal deaths. Wrigglesworth JS. Lancet 1982;i:264-7.

Right Sided Pulmonary Hypoplasia: Scimitar syndrome

partial or complete anomalous pulmonary venous drainage into the inferior vena cava, commonly associated with:persistent left superior vena cava, dextrocardia, pulmonary sequestration, right pulmonary hypoplasia

If pulmonary hypoplasia is right sided

pulmonary vasculature

must be visualised because of the

association with Scimitar syndrome

If pulmonary hypoplasia is right sided

pulmonary vasculature

must be visualised because of the

association with Scimitar syndrome

tachypnoea, recurrent pneumonia, failure to thrive and heart failure.

the infantile form of Scimitar tends to

present in the first 2 months with:

The triad of:1) respiratory distress, 2) right lung hypoplasia, and 3) dextroposition of the heart

should alert the clinician to think of scimitar syndrome.

Right Sided Pulmonary Hypoplasia: Scimitar syndrome

Congenital Diaphragmatic Hernia

Often diagnosed antenatally or within hours or days of birth.

However late-presenting (>1 month) is well

recognised, Tachypnoea

Vomiting most common symptoms

Diaphragmatic Weakness

the chest wall is so compliant, the mediastinum is more mobile the intercostal muscles are weaker

the diaphragm is critical

to respiration in infancy

due to the fact

Even unilateral diaphragmatic weakness can cause a degree

of respiratory distress.





due to the fact



at this age, phrenic nerve injury

is the most common cause.





due to the fact



at this age, phrenic nerve injury

is the most common cause.

When due to a difficult delivery, for example, following shoulder dystocia,

the majority of infants with phrenic nerve palsy also have a brachial plexus injury (Erb’s palsy). (a

paralysis of the arm caused by injury to the upper group of the arm's main

nerves)

Diaphragmatic paralysis associated with neonatal brachial plexus palsy. Bowerson M, Pediatr Neurol

2010;42:234–6.

newborns with brachial plexus palsy evaluated during 2005-2009 (n = 166) at University of Michigan Medical School

3 –

2 –

1 –

0 -

of patients with brachial plexus palsy % with clinically significant diaphragmatic palsy

2.4% (4/166)of these, a majority (75%; n = 3)

manifested respiratory complications sufficient to warrant diaphragmatic

plication


congenital neuromuscular disorders

can cause severe diaphragmatic

weakness.

spinal muscular atrophy with respiratory distress (SMARD1)

unlike more typical spinal muscular atrophies,

presents with respiratory distress before distal muscular weakness is

obvious


The respiratory difficulty is due to diaphragmatic weakness followed by paralysis (usually on the right side initially),

Usually accompanied by a weak cry and stridor.

A chest X-ray may indicate an abnormal position of a hemidiaphragm.

An ultrasound or fluoroscopic examination of the diaphragms can demonstrate abnormal movements, especially if paradoxical or weak/paralysed.

congenital neuromuscular disorders

can cause severe diaphragmatic

weakness.

spinal muscular atrophy with respiratory distress (SMARD1)

unlike more typical spinal muscular atrophies,

presents with respiratory distress before distal muscular weakness is

obvious

H-type tracheo-oesophageal fistula.

85% <1%

2% 8% 4%

as well as tachypnoea, the child would have marked symptoms on feeding, usually:

1) coughing, 2) choking, 3) turning blue and 4) potentially recurrent

lung infections.

A tube oesophagram (video oesophagography)and/or bronchoscopy may benecessary to make the diagnosis,

Upper Airway NarrowingIt may be obvious due to the presence of significant or persisting stridor, especially if the narrowing is more than mild.

Possible causes:

1)laryngotracheomalacia,

2)bronchomalacia,

3)laryngeal or tracheal web,

4)subglottic stenosis. subglottic stenosis

tracheomalacia

Upper Airway NarrowingIt may be obvious due to the presence of significant or persisting stridor, especially if the narrowing is more than mild.

Possible causes:

1)laryngotracheomalacia,

2)bronchomalacia,

3)laryngeal or tracheal web,

4)subglottic stenosis. subglottic stenosis

tracheomalacia

Tachypnoea accompanied

by noisy breathing is an indication

for bronchoscopy

Nasal obstruction in newborns.Gnagi SH, Pediatr Clin North Am. 2013;60(4):903-22.

Newborn infants are obligate nasal breathers for the first several months of life, with more than 50% of infants desaturating if nasally obstructed.

Anatomically, their entire tongue length is in contact with the hard and soft palate, and the epiglottis is superior to the soft palate, causing difficulty with oral breathing.

This allows for concomitant respiration with oral intake while the infant is learning to mouth breathe in the first 4 to 6 weeks after birth. epiglottis position for

breathing swallowing


Newborn infants are obligate nasal breathers for the first several months of life, with more than 50% of infants desaturating if nasally obstructed.

Anatomically, their entire tongue length is in contact with the hard and soft palate, and the epiglottis is superior to the soft palate, causing difficulty with oral breathing.

This allows for concomitant respiration with oral intake while the infant is learning to mouth breathe in the first 4 to 6 weeks after birth. epiglottis position for

breathing swallowing

nasal obstruction may lead to serious consequences in the neonate, including respiratory distress or failure to thrive.


Nasal endoscopy revealing membranous occlusion of the posterior nasal cavityconsistent with choanal atresia.

Axial CT showing atretic choanae. Circle encompasses atresia at posterior nasal vault.Note the champagne flute appearance of the nasal vaults characteristic for choanal atresia.coloboma bilaterale dell'iride

fessura a forma di buco della serratura


SYNDROMIC ASSOCIATIONS

Several etiologies of nasal obstruction may present with concurrent abnormalities that may require further assessment, including genetic evaluation:Crouzon, CHARGE, Pfeiffer, Apert, Treacher-Collins, Down, Fetal alcohol syndromes

nasal obstruction +

plagiocephaly


CTscan of a child with Congenital nasal pyriform aperture stenosis. Note the

inward bowing of the nasal processes of the maxillary bone

with the pyriform aperture (the anterior nasal aperture) measuring 7 mm

(arrows).

Child with Congenital nasal pyriform aperture stenosis and evidence of

a single central megaincisor.


Sagittal magnetic resonance image of a basal meningocele protruding

into the nasopharynx.

Neonatal iatrogenic nasal obstruction

Naso-endoscopy revealing synechia on the right side from CPAP

catheters.

Nasal obstruction

Unilateral obstruction may present later (typically at 5–24 months), and with milder symptoms;

Unilateral atresia is more common than bilateral and accounts for up to 75% cases of atresia.

Symptoms will be milder if it is a stenosis rather than complete atresia.

Techniques for diagnosis

1) placing a cold mirror/metal spoon under the nostril to look for condensation,

2) passing a small nasogastric tube,

3) putting a few drops of saline in the nostril and looking for bubbles

CardiacCardiovascular disease may present initially during infancy with just mild tachypnoea.

With increasing symptoms of tachypnoea and recurrent chest infections, cardiac disorders may masquerade as respiratory disease.

Many causes are ‘silent’ meaning there is no murmur, so the diagnosis is not always obvious without assessment by a cardiologist.

In many conditions mild arterial oxygen desaturation is not clinically obvious

After careful examination by the cardiologist,

inevitably children will have an

ECG and echocardogram

performed to exclude a number of

potential cardiac diagnoses.

Gastrointestinal

A pH study should be diagnostic, and in an infant a dual probe study is preferable in order to takeaccount of any buffering of stomach acid by frequent milk feeds.

Gastro-oesophageal reflux

oesophagitis

tachypnoeabut it would need to be quite severe to cause persistent symptoms;the child would not necessarily be vomiting.

A key discriminator: GOR or GORD.

GOR: The passage of gastric contents into the oesophagus, with or without regurgitation/ vomiting; it is considered physiological ininfants when symptoms are absent or not troublesome,

GORD: The presence of troublesome symptoms(ie, those that adversely affect the well-being of the child) and/or complications (eg, tissue damage or inflammation, as in oesophagitis, reactive airways disease or pulmonary aspiration).

Gastrointestinal

often idiopathic,sometimes associated with a bulbar palsy, occasionally anatomical (eg, laryngeal cleft)velopharyngeal insufficiency (submucous clefting).

Recurrent aspiration of fluid

(eg, milk, saliva) when drinking the baby does not necessarily: cough, splutterchoke.

can sometimes be silent

DiGeorge Syndrome ?

Gastrointestinal





DiGeorge Syndrome

lipid ladenmacrophages.

Nasal regurgitation of milk can be an

unmasking sign !

the opening of upper esophageal sphincter

significantly decreased in the cases of nasal

backflow.

X

Gastrointestinal





DiGeorge Syndrome

Diagnosis is made by a

speech therapist’s clinical assessment,sometimes followed

by a videofluoroscopicswallowing study.

lipid ladenmacrophages.

congenital heart disease,

infection,

upper airway anomalies (narrow trachea, laryngomalacia,tracheomalacia and bronchomalacia),

aspiration due to gastro-oesophageal reflux or swallowing abnormalities.

Trisomy 21

in babies with Down’s syndrome



[email protected]





OUTCOMEtachypnoea usually resolves, but may take as long as 6–12 months.

in the absence ofan underlying condition

this means that thecause in most babies

is never determined.

the improvement may be due to:

1) maturation of automatic control of breathing (based in the

brainstem),

2) response to chemoreceptors, or

3) a change in the mechanical properties (compliance and volumes) of the lungs and chest wall.

OUTCOMEtachypnoea usually resolves, but may take as long as 6–12 months.

in the absence ofan underlying condition

this means that thecause in most babies is never determined.

the improvement may be due to:

1) maturation of automatic control of breathing (based in the

brainstem),

2) response to chemoreceptors, or

3) a change in the mechanical properties (compliance and volumes) of the lungs and chest wall.

In those with a specific diagnosis, the outcome will depend on the

actual diagnosis.



[email protected]





Summary & Conclusions

Respiratory rate has to be counted with the stethoscope (for 30 sec. twice than add) while the child is asleep.

Tachypnoea (> 60 breaths/min in the first months of life) may be an self-solving problem but can also be a sign of a severe conditions expecially if associated with hypoxia, failure to thrive, and cardiac signs and symptoms.

Persistent cough, Apnoeic episodes, Noisy breathing, Poor feeding, Vomiting, Choking when drinking are signs for concern.

Summary & Conclusions

If the clinical examination is not completely negative imediate investigations are: SaO2 and Chest X-ray, followed by ECG & Echo, and blood gases.

When the diagnosis is not immediate obvious referal is necessary for: CT scan, bronchoscopy & biopsy, and genetics.

When your are faced with a tachypnoeic infant it will be wise to maintain a certain degree of uncertainty and to look for all the possibilities.

If you only trust your memory and experience I am afraid you may do some mistakes.

19° FORMAT Verona 12-13/05/2017

Grazie per la vostra attenzione alla storia che

vi ha raccontato il mio nonno.

Ciao a tutti.Mia Charlize Powell

Format 2016: tachypnoea in a well baby: what to do next?

Health & Medicine

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