Detection of subclinical CO2 embolism by transesophageal echocardiography during laparoscopic radical prostatectomy

Abstract

OBJECTIVES: To document incidences of subclinical embolism in laparoscopic radical prostatectomy with continuous monitoring using transesophageal echocardiography (TEE).

METHODS: A 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%.

RESULTS: Gas 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 CO(2) partial pressure.

CONCLUSIONS: Subclinical 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.