[Intraoperative detection of air embolism and corpuscular embolism using pulse oximetry and capnometry. Comparative...

19 patients undergoing total hip replacement in general anesthesia because of transcervical femur fractures were continuously monitored throughout surgery to detect any embolic events. Aside from the standard monitoring with ECG and control of arterial pressure in regular short intervals, the pulse-oximetry and capnography were applied for a comparative examination of their sensitivity in detecting gas and corpuscular embolisms. Transesophageal echocardiography (TEE) which allows an extensive assessment regarding the extent and differentiation between gaseous and corpuscular embolisms was chosen as a reference method. The examination concentrated on the implantation of the acetabulum and femur prosthesis since this phase of the operation has been associated with a high incidence of embolisms. The TEE monitoring revealed corpuscular as well as gaseous emboli during surgery. In the 36 cases of echocardiographic detectable embolisms prospectively defined changes of the heart rate were observed in 17%, of the mean arterial pressure in 56%, of the end-expiratory CO2 partial pressure in 47% and of the arterial O2 saturation in 31% of the cases. The embolisms which had been categorized by means of TEE according to their severity reflected a decrease of the end-expiratory CO2 partial pressure in 25% of the cases with light, in 45% of the cases with moderate and in 69% of the cases with severe embolisms, whereas a decrease in arterial O2 saturation was detected in 8% with light, 27% with moderate and in 54% of the cases with severe embolisms. Corpuscular embolism had no stronger influence on the frequency of relevant changes of end-expiratory CO2 partial pressure and the arterial O2 saturation than did the gaseous emboli.(ABSTRACT TRUNCATED AT 250 WORDS)