In Reply:-Dr. Schulz-Stubner brings up an excellent therapeutic option for those patients undergoing laser treatment of endobronchial lesions who suffer a cerebral air embolus. In the three patients we described in our report, only the second patient would fit into this category. The first patient, we believe, suffered a helium gas embolus, delivered from the coaxial gas channel of the laser. We are not aware that there is any evidence that hyperbaric therapy is efficacious in this incidence. The second patient suffered an air and oxygen mixture gas embolus, and certainly hyperbaric therapy should be considered in this situation. The third patient's cerebral gas embolus was, we believe, 100% oxygen, and this rapidly dissolved without any neurologic deficit. Because many institutions do not have hyperbaric facilities readily available and because these patients often are not in the best physical condition to travel, the use of high concentrations of oxygen, when the risk of combustion is limited, is, perhaps, another alternative technique for avoiding a permanent deficit if a cerebral gas embolus occurs.
However, before hyperbaric therapy can be considered, the appropriate diagnosis needs to be made because the differential diagnosis of cerebral metastatic lesion or cerebral vascular accident may confuse the clinical picture unless the associated electrocardiographic changes and other evidence of systemic gas embolism are recognized.
Michael A. E. Ramsay, M.D.
Department of Anesthesiology and Pain Management; Baylor University Medical Center; 3500 Gaston Avenue; Dallas, Texas 75246
(Accepted for publication September 9, 1997.)