Surrounding soft tissue pressure during shoulder arthroscopy.

In 40 patients undergoing arthroscopic subacromial decompression, we monitored the soft tissue pressure in the paratracheal region and in the deltoid and supraspinatus muscles, looking for evidence of a potentially dangerous rise in pressure, especially in the paratracheal region. Statistical analysis was used to determine predictable variables of the time of reaching maximum pressure in and between the three regions. Deltoid pressure rose quickly during surgery, and did not drop to baseline levels at the end of surgery. Supraspinatus pressures showed a similar trend but with lower maximum levels of pressure rise. Five patients had an (unexpected) rise in paratracheal pressure, with an absolute maximum of 133.4 mmHg in one. In only two patients, did "10 minutes post-op" paratracheal pressure levels not drop to baseline levels. No respiratory problems occurred during any procedure. There are no variables to predict a potentially dangerous rise in surrounding soft tissue pressure during shoulder arthroscopy. We recommend endotracheal intubation during shoulder arthroscopy.