Venous carbon dioxide embolism in pigs: an evaluation of end-tidal carbon dioxide, transesophageal echocardiography, pulmonary artery pressure, and precordial auscultation as monitoring modalities
Couture, P.; Boudreault, D.; Derouin, M.; Allard, M.; Lepage, Y.; Girard, D.; Blaise, G.
Anesthesia and Analgesia 79(5): 867-873
1994
ISSN/ISBN: 0003-2999 PMID: 7978402 Document Number: 438905
We evaluated the effects of CO-2 embolism on end-tidal carbon dioxide (ETCO-2) and compared four methods for detection of gas embolism. Fourteen pigs were monitored for CO-2 embolism with transesophageal echocardiography (TEE), changes in ETCO-2, changes in mean pulmonary artery pressure (MPAP), and precordial auscultation (AUSC). Serial injections of CO-2 (ranging from 0.05 to 5.0 mL/kg) were performed in seven pigs (Group 1). In the other seven pigs, CO-2 was infused at rates between 0.01 and 0.4 mL cntdot kg-1 cntdot min-1 (Group 2). Positive responses were defined as an acute change in heart sounds (AUSC), visualization of gas bubbles in the right cardiac chambers on TEE, an increase in MPAP gtoreq 3 mm Hg, and an acute change (increase or decrease) in ETCO-2 gtoreq 3 mm Hg. In both groups, positive response to CO-2 embolism were represented by an initial decrease in ETCO-2. The frequency with which positive responses were observed revealed that TEE was the most sensitive method (P lt 0.05), whereas no differences were found among the other methods. In conclusion, in this model, positive response to CO-2 embolism was represented by a decrease in ETCO-2. TEE was the most sensitive method of detection of CO-2 embolism, and ETCO-2, MPAP, and AUSC were equally sensitive.