"Slow puncture" of a pulmonary artery catheter balloon.

Abstract

Pulmonary artery false aneurysm formation, induced by a Swan-Ganz catheter is a well-known complication that may be caused by repeated manipulations and a too far advanced tip of the catheter. It is estimated to occur in 0.06 to 0.2% of cases with pulmonary artery catheter and is associated with a mortality rate of 45 to 65%(1–3). Prior to cardiac transplantation surgery, we recently introduced a pulmonary artery catheter (Swan-Ganz CCOmbo V CCO/SvO2/CEDV REF 744 HF 75, Edwards Lifesciences, Germany) through an 8.5F introducer sheath (Percutaneous Sheath Introducer Set REF Product No SI-09875-E, Arrow, Germany). After in vitro calibration, the catheter was removed from its package. While routinely flushing the catheter ports, wetting the balloon and catheter, and testing of the balloon by inflating it and then releasing the inflation syringe before insertion into the patient, no problems were obvious. Then the catheter was inserted cautiously into a contamination shield with the proximal and distal hubs in the widest open position. The left internal jugular vein was cannulated with the introducer sheath. After cautious insertion of the catheter through the introducer sheath, the balloon was inflated by filling it slowly with 1.5 mL of air. Then the catheter was advanced under pressure-wave guidance, showing normal wave patterns. The catheter was advanced incrementally until 65 cm. Only pulmonary artery but no wedge tracing could be obtained. The inflation syringe was released, and only 0.5 mL of air released spontaneously back into the syringe. Under the perception of a damaged balloon, it was decided to replace the catheter. When the catheter was removed, the balloon seemed still intact. It expanded symmetrically when the air was inflated rather quickly. The inflated 1.5 mL of air released back into the syringe. Therefore, the same catheter was reinserted, but again no wedge tracing could be detected, and the catheter was removed again. Another Swan-Ganz catheter from the same manufacturer, but with a different production date, was placed. This time wedge tracing was seen at 62 cm. Later on the testing of the first catheter revealed that slow inflation of the balloon allowed the escape of air through a tiny hole. The balloon remained flat. The damaged catheter was send to the manufacturer for investigation. To date, we have not received any report on their results. This is our own explanation for the observed phenomenon: The puncture in the balloon needs to be positioned in the fold, meaning the junction between the catheter and the balloon. In the case of rapid inflation, more air enters the balloon than can escape through the puncture, and once the balloon is fully inflated, the puncture is sealed by being within the fold. Slow inflation means that air can escape through the puncture at a rate more equal to that of inflow, therefore the balloon cannot expand and the puncture will not be covered. We would like to bring to the attention of the reader that, despite obeying all rules and precautions, mechanical damage of a balloon may not be recognized. The catheter was removed from an undamaged package without problem; it seems unlikely that it was damaged at that time. Also protective sheaths are known sources for damage to the balloon. Again all precautions to prevent damage have been fulfilled: wetting of catheter and balloon, widest opening of the hubs, and cautious insertion into the introducer sheath (4). After repeated pre-and reinsertion testing, the damage of the balloon could not be anticipated. But a high index of suspicion prevented the operator from further advancement of the catheter that could have caused pulmonary artery rupture. The exchange of the catheter proved to be the right decision. The respective catheter was sent for further investigation to the manufacturer. The patient did not experience any adverse outcome from placing the PA-catheter. W. Schummer, MD C. Schummer, MD J. Fuchs, MD