c. Insert the Needle. Firmly insert the needle into the skin above the top of the
third rib into the second intercostal space at a 90-degree angle (figure 4-6). Continue
inserting the needle until the chest cavity has been penetrated. You will feel a "pop" as
the needle enters the chest cavity. A hiss of escaping air under pressure should be
Proper positioning of the needle is essential to avoid damaging blood
vessels and nerves that run along the bottom of each rib.
d. Withdraw the Needle. Withdraw the needle while holding the catheter in
place. The catheter will remain as a means for air trapped in the chest to escape to the
e. Secure the Catheter. Use the strip of tape to secure the catheter hub to the
chest wall. Figure 4-7 illustrates a casualty with a catheter and flutter valve dressing in
Figure 4-7. Casualty with catheter in place to relieve tension pneumothorax.
f. Monitor Casualty. By allowing trapped air to escape from the plural area,
the casualty's respirations should quickly improve. Applying airtight material over the
wound and having a catheter release trapped air permits the affected lung to re-inflate
somewhat. If possible, monitor the casualty until medical care arrives or until the
casualty is evacuated to the nearest medical facility. Be prepared to take measures to
treat for shock.
g. Transport Casualty. If you have performed a needle decompression on a
casualty with a tension pneumothorax, he should be transported injured side up rather
than injured side down in order to allow access to the needle during transport. The
casualty may be transported in a sitting-up position if the casualty finds that position