Detection of Subclinical CO2 Embolism by Transesophageal Echocardiography During Laparoscopic Radical Prostatectomy

ObjectivesTo document incidences of subclinical embolism in laparoscopic radical prostatectomy with continuous monitoring using transesophageal echocardiography (TEE).MethodsA total of 43 patients scheduled for elective robotic-assisted laparoscopic radical prostatectomy under general anesthesia were enrolled in this study. A 4-chamber view of 5.0-MHz multiplane TEE was continuously monitored to detect any intracardiac bubbles as an embolism. An independent TEE specialist reviewed the tapes for interpretation, and emboli were classified as 1 of 5 stages. Cardiorespiratory instability during gas emboli entry was defined as an appearance of cardiac arrhythmias, sudden decrease in mean arterial blood pressure >20 mm Hg, or an episode of pulse oximetric saturation <90%.ResultsGas embolisms were observed in 7 of 41 (17.1%) patients during transection of the deep dorsal venous complex. Of them, 1, 3, 1, and 2 showed stage I, II, III, and IV, respectively. However, there were no signs of cardiorespiratory instability associated with emboli. The 95% confidence interval for gas embolism was 0.204%-0.138%. No correlation was observed between episodes of gas embolism and blood gas variables or end-tidal CO2 partial pressure.ConclusionsSubclinical gas embolisms occur in 17.1% of laparoscopic radical prostatectomies. We should consider that this procedure has a potential for serious gas embolism, especially with the increasing popularity of laparoscopic prostatectomy using robot-assisted techniques.