Neonatal Tension Pneumothorax
A ventilated 1.4 kg infant born at 29 weeks with hyaline membrane disease deteriorates on day 2. Oxygen saturation falls from 94 to 62 percent, heart rate to 78 beats/min, and blood pressure to 32/18 mm Hg. Breath sounds are absent over the right hemithorax, the trachea is deviated to the left, and transillumination of the right chest is increased. Where should the needle be inserted for immediate decompression?
- A.Fifth intercostal space, midaxillary line
- B.Second intercostal space, midclavicular lineCorrect
- C.Third intercostal space, midclavicular line
- D.Fourth intercostal space, anterior axillary line
Explanation
Tension pneumothorax is a clinical diagnosis and an immediate life threat, so needle decompression must precede radiographic confirmation whenever there is hemodynamic compromise. In the neonate the classic bedside findings are sudden desaturation, bradycardia, hypotension, unilateral absent breath sounds, tracheal and apical impulse shift away from the affected side, and a positive transillumination test, which is uniquely useful in infants because the chest wall is thin. Emergency decompression is performed by inserting a needle or angiocatheter, often attached to a three-way tap and syringe, into the second intercostal space in the midclavicular line, passing over the upper border of the third rib to avoid the neurovascular bundle that runs along the lower border of each rib. This anterior superior position reliably reaches the apical air collection in a supine infant. Once the tension is relieved, a formal intercostal chest drain is placed and connected to an underwater seal. Preterm infants on positive pressure ventilation for surfactant deficiency are at particular risk of air leak because of stiff, poorly compliant lungs and high inflating pressures, and the risk is reduced by gentle ventilation strategies and early surfactant. Other air leak syndromes to recognize are pneumomediastinum, pulmonary interstitial emphysema, and pneumopericardium. The lateral fourth or fifth intercostal space approach is the position used in adult trauma protocols and for definitive chest drain placement, not for the emergency neonatal needle.
Why each option
- A.
- The fifth space midaxillary line risks diaphragmatic and hepatic injury in a small infant and is not used for emergency decompression.
- B.
- Correct. The second intercostal space in the midclavicular line, over the top of the third rib, is the standard neonatal needle decompression site.
- C.
- The third space is too low for reliable access to the apical air collection and is not the standard landmark.
- D.
- The fourth space anterior axillary line is an adult trauma landmark and a chest drain site, not the emergency neonatal needle site.
Reference: AAP and AHA Neonatal Resuscitation Program Guidelines, 8th ed., 2021
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