Neonatal pneumothorax is the accumulation of air in the pleural cavity, which can collapse the lung. It occurs most commonly in preterm infants and those with underlying lung conditions requiring ventilation support. Symptoms range from none in mild cases to respiratory distress and hypotension in severe cases. Diagnosis is confirmed by chest x-ray showing hyperlucent lung fields. Small pneumothoraces may be observed but symptomatic or tension pneumothoraces require needle aspiration or chest tube placement to re-expand the lung. Persistent pneumothoraces lasting over a week sometimes require additional interventions like HFOV. Prognosis depends on the underlying condition but early and effective treatment prevents complications.
2. Pneumothorax
Definition
A pneumothorax is the accumulation
of extrapulmonary air with in the
pleural cavity.
Pneumothorax is one of the most
common air leak syndromes that
occurs more frequently in the
neonatal period than in any other
period of life and is a life-threatening
condition associated with a high
incidence of morbidity and mortality
3. Incidence
The exact incidence of the Pneumothorax is difficult
to determine. It is reported to occur spontaneously in
1–2% of all neonates. The incidence increases in
preterm infants to about 6%. The incidence also
increases to 9–10% in infants with underlying lung
disease (such as RDS, meconium aspiration,
pneumonia, and pulmonary hypoplasia) who are on
ventilatory support, and in infants who had vigorous
resuscitation at birth.
4. • The prevalence of neonatal Pneumothorax in the NICU of
'Ad-din Women’s Medical College' Dhaka, between January
2016 & December 2017 was 2.60% & that of Spontaneous
Pneumothorax was 1.53% although they conducted this
study with a very small sample size with only 83 neonates.
source -
Spectrum of Neonatal Pneumothorax at a Tertiary Care Hospital of Bangladesh : A
Retrospective Observational Study.
Bangladesh Crit Care J March 2019; 7 (1): 12-19
5.
6.
7. Common causes in case of neonates includes
pulmonary hypoplasia, pulmonary space-occupying
lesions (diaphragmatic hernia), thoracic abnormalities
(thoracic dystrophies), High Ventilatory support,
continuous positive airway pressure(CPAP),Meconium
Aspiration syndrome, RDS, TTN, congenital pneumonia,
cystic fibrosis, prematurity, low birth weight, infants
who were resuscitated at birth, etc.
8. Types of pneumothorax
A. Spontaneous pneumothorax
• 1. Primary spontaneous pneumothorax (PSP). Occurs
when there is no obvious precipitating factor, no clear
cause, it is idiopathic, without lung disease. Familial
spontaneous pneumothorax is a rare cause in
neonates and have been associated with mutations in
the folliculin gene (FCLN)
2. Secondary spontaneous pneumothorax (SSP). Occurs
from underlying lung disease (respiratory distress
syndrome [RDS], meconium aspiration syndrome
[MAS], and others).
9. B. Traumatic pneumothorax
1. Iatrogenic occurs from an accidental insult during a
procedure such as central line placement or
thoracentesis.
2. Positive pressure ventilation (mechanical or
noninvasive ventilation) can cause barotrauma.
3. Chest trauma can occur when blunt or penetrating
trauma occurs to the chest (rare in neonate).
10. C. Tension pneumothorax.
A life-threatening condition occurs if an accumulation of
air within the pleural space is sufficient to elevate
intrapleural pressure above atmospheric pressure.
Unilateral tension pneumothorax results in impaired
ventilation not only in the ipsilateral lung but also in the
contralateral lung owing to a shift in the mediastinum
toward the contralateral side.
11. Air goes into the pleural cavity during inspiration,
but no air is allowed to escape during expiration. It
acts as a 1-way valve. Because air is trapped,
intrathoracic positive pressure rises, lung volume
decreases, and pressure compresses the
mediastinum and causes a shift, with increased
pulmonary vascular resistance. This results in an
increase in central venous pressure, decrease in
venous return to the heart, and a decrease in
cardiac output. This causes displacement of
mediastinal structures and cardiopulmonary
compromise.
14. PATHOGENESIS
The tendency of the lung to collapse, or elastic recoil, is
balanced in the normal resting state by the inherent
tendency of the chest wall to expand outward, creating
negative pressure in the intrapleural space. When air
enters the pleural space, the lung collapses. Hypoxemia
occurs because of alveolar hypoventilation, ventilation–
perfusion mismatch, and intrapulmonary shunt.
15. In simple pneumothorax, intrapleural pressure is
atmospheric, and the lung collapses up to 30%. In
complicated, or tension, pneumothorax, continuing leak
causes increasing positive pressure in the pleural space,
with further compression of the lung, shift of
mediastinal structures toward the contralateral side,
and decreases in venous return and cardiac output.
16. Clinical presentation
` May be asymptomatic in mild cases of spontaneous
pneumothorax
Moderate cases may present with classic signs of
respiratory distress (grunting, flaring, retractions, and
tachypnea).
In severe cases may present with cyanosis, decreased
oxygen saturation, hypotension, bradycardia,
hypoxemia, hypercarbia, and respiratory acidosis
17. On clinical examination
Inspection - The chest may appear asymmetric
with an increased anteroposterior diameter and
bulging of the intercostal spaces on the affected
side
Palpation – Trachea and apex beat may shifted
towards the unaffected side
Auscultation – hyperresonance and diminished
or absence of breath sounds.
18. Diagnosis
A. Physical examination
B. Laboratory studies
Blood gas levels may show decreased Pao2 and
increased Pco2 with resultant respiratory acidosis.
19. C. Imaging and other studies
Transillumination of the chest - With the aid of
transillumination, the diagnosis of pneumothorax may
be made without a chest radiograph.
A fiber-optic light probe placed on the infant’s chest wall
will illuminate the involved hemithorax. Although this
technique is beneficial in an emergency, it should not
replace a chest radiograph as the means of diagnosis.
20.
21. Chest radiograph –
Anteroposterior (AP) view of the chest
Radiographically, a pneumothorax is diagnosed on the
basis of the following characteristics:
i. Presence of air in the pleural cavity separating the
parietal and visceral pleura. The area appears
hyperlucent with absence of pulmonary markings.
ii. Collapse of the ipsilateral lobes.
iii.Displacement of the mediastinum toward the
contralateral side.
iv. Downward displacement of the diaphragm.
22. 2. Collapse of left lung
3. Depression of the lt diaphragm
4. Shift of mediastinal stractures
1. Hyperlucent with absence of
pulmonary markings
23. Cross-table lateral view
will show a rim of air around the lung
(“pancaking”). It will not help to identify the
affected side. we must have an AP film to
identify the side of the pneumothorax. This film
must be considered together with the AP view to
identify the involved side. Pleural air tends to
collect anteriorly and may require the CT or
lateral decubitus view.
24.
25. Lateral decubitus view (shot through the AP
position)
will detect even a small pneumothorax not seen
on a routine chest radiograph. The infant should
be positioned so the side of the suspected
pneumothorax is up (eg, if pneumothorax is
suspected on the left side, the film is taken with
the left side up).
26.
27. Ultrasound examination of the lungs
The absence of lung sliding (grainy appearance) and
comet tails (normal pleura reflecting sound waves)
confirms the ultrasound diagnosis of a pneumothorax.
The sensitivity and specificity of ultrasound is 100% and
93% for a complete pneumothorax, and 79% and 100%
for a radio-occult pneumothorax. As a bedside tool, this
is useful to diagnose a pneumothorax.
28. Transcutaneous monitoring of carbon dioxide
Transcutaneous carbon dioxide (CO2) analysis was
introduced in the early 1980s using locally heated
electrochemical sensors that were applied to the
skin surface. This methodology provides a
continuous noninvasive estimation of the
arterial CO2 value and can be used for assessing
adequacy of ventilation.
32. Treatment of pneumothorax
A. Asymptomatic or minimally symptomatic
pneumothorax
(positive-pressure mechanical ventilation is not
being administered and there is no underlying
lung pathology)
Close observation with follow-up chest radiographs
every 8–12 hours. The pneumothorax will likely resolve
within 24–48 hours.
33. Nitrogen washout therapy Administration of 100% or
>3l/min o2
Decrease PN2 in alveolus
Increase PN2 in intraplural air
The total gas tension is decrease
due to elimination of N2
O2 rapidly absorbed and
resolution of Pneumothorax
34. Symptomatic pneumothorax
Needle aspiration and possible chest tube
placement.
If positive-pressure mechanical ventilation is
being used A chest tube will probably need to
be inserted because the ventilator pressure
will prevent resolution of the pneumothorax
and tension pneumothorax may develop.
35. Sometimes needle aspiration is all that is
needed. If a pneumothorax develops in a
patient who is ready to be extubated, clinical
judgment must be used in deciding whether a
chest tube should be placed.
36. Tension pneumothorax
Tension pneumothorax is an emergency. A 1 to 2
minute delay could be fatal. If a tension pneumothorax
is suspected, act immediately. It is better to treat in this
setting, even if it turns out that there is no
pneumothorax. There is no time for x-ray confirmation.
If the patient’s status is deteriorating rapidly, a needle
or catheter over needle can be placed for aspiration,
followed by formal chest tube placement.
37. • Needle aspiration
The site of puncture should be at the second
intercostal space along the midclavicular line
on the suspected side of pneumothorax.
Cleanse this area with antibacterial solution.
The fourth intercostal space at the anterior
axillary line can also be used.
38. Connect a 23- or 25-gauge butterfly needle or a 22- or
24-gauge catheter over needle (Angiocath) to a 10–
20-mL syringe with a stopcock attached.
Palpate the third rib at the midclavicular line. Insert
the needle (perpendicular to the chest surface) over
the top of the third rib at the second intercostal
space, and advance it until air is withdrawn from the
syringe.
39. Have an assistant hold the syringe to withdraw the
air. The needle may be removed before the chest
tube is placed if the infant is relatively stable, or it
may be left in place for continuous aspiration while
the chest tube is being placed. If an Angiocath is
used, the needle can be removed and the catheter
left in place.
42. Persistent pneumothorax
Generally defined as a pneumothorax that persists >7
days in the absence of mechanical problems.
Sometimes infants who have chest tubes still have air
leaks that persist for more than a week. These infants
have episodes of instability when air reaccumulates;
some require a new or replacement chest tube and an
increase in their ventilator settings. These are treated
to decrease the complications associated with air leaks
(air embolus, hypotension, intracranial hemorrhage).
43. The following have been used:
• High-frequency oscillatory ventilation
(HFOV) or high-frequency jet ventilation
• Unilateral lung intubation
• Fibrin glue
44. surgery in the treatment of
pneumothorax
If the patient has had repeated episodes of
pneumothorax or if the lung remains unexpanded
after 5 days with a chest tube in place, operative
therapy such as the following may be necessary:
• Thoracoscopy: Video-assisted thoracoscopic
surgery (VATS)
• Electrocautery: Pleurodesis or sclerotherapy
• Laser treatment
• Resection of blebs or pleura
• Open thoracotomy
45. Prognosis
Largely depends on underlying conditions. In general
if treated rapidly and effectively the long term
outcome should not be changed. But early onset
(less then 24 hours of age) is always associated with
high mortality rate. Pneumothorax is also describe as
a risk factor for intraventricular hemorrhage ,
cerebral palsy and delayed mental development.