Pulmonary Edema after Catastrophic Carbon Dioxide Embolism during Laparoscopic Ovarian Cystectomy

Laparoscopy is a surgical procedure used both for diagnosis and for various treatments. A rare but sometimes fatal complication of laparoscopy is pulmonary embolism with CO2 resulting in pulmonary edema. During laparoscopic gynecological surgery in a 29-year-old woman who had previously undergone lower abdominal surgery, the end-tidal CO2 suddenly increased from 40 mmHg to 85 mmHg and then decreased to 13 mmHg with hemodynamic deterioration. These events are characteristic of a CO2 embolism. When this occurred, CO2 insufflation was immediately stopped and the patient was resuscitated. The patient's condition gradually improved with aggressive treatment, but the clinical course was complicated by bilateral pulmonary edema. This case of pulmonary edema was soon resolved with supportive management. The formation of a CO2 embolism during laparoscopy must be suspected whenever there is a sudden change in the end-tidal CO2. In addition, the possibility of pulmonary edema should be considered when a CO2 embolism occurs

Oxygenator Exhaust Capnography for Prediction of Arterial Carbon Dioxide Tension During Hypothermic Cardiopulmonary Bypass

Continuous monitoring and control of arterial carbon dioxide tension (PaCO2) during cardiopulmonary bypass (CPB) is essential. A reliable, accurate, and inexpensive system is not currently available. This study was undertaken to assess whether the continuous monitoring of oxygenator exhaust carbon dioxide tension (PexCO2) can be used to reflect PaCO2 during CPB. A total of 33 patients undergoing CPB for cardiac surgery were included in the study. During normothermia (37°C) and stable hypothermia (31°C), the values of PexCO2 from the oxygenator exhaust outlet were monitored and compared simultaneously with the PaCO2 values. Regression and agreement analysis were performed between PexCO2 and temperature corrected-PaCO2 and temperature uncorrected-PaCO2. At normothermia, a significant correlation was obtained between PexCO2 and PaCO2 (r = 0.79; p < 0.05); there was also a strong agreement between PexCO2 and PaCO2 with a gradient of 3.4 ± 1.9 mmHg. During stable hypothermia, a significant correlation was obtained between PexCO2 and the temperature corrected-PaCO2 (r = 0.78; p < 0.05); also, there was a strong agreement between PexCO2 and temperature corrected-PaCO2 with a gradient of 2.8 ± 2.0 mmHg. During stable hypothermia, a significant correlation was obtained between PexCO2 and the temperature uncorrected-PaCO2 (r = 0.61; p < 0.05); however, there was a poor agreement between PexCO2 and the temperature uncorrected-PaCO2 with a gradient of 13.2 ± 3.8 mmHg. Oxygenator exhaust capnography could be used as a mean for continuously monitoring PaCO2 during normothermic phase of cardiopulmonary bypass as well as the temperature-corrected PaCO2 during the stable hypothermic phase of CPB

End-Tidal CO

This prospective study included 32 patients undergoing cardiopulmonary bypass (CPB) for elective coronary artery bypass grafting correlates the respiratory end-tidal CO2 (ETCO2) during partial separation from CPB with cardiac output (CO) following weaning from CPB. After induction of general anesthesia, a pulmonary artery catheter was inserted for measurement of cardiac output by thermodilution. Patients were monitored using a 5-lead ECG, pulse oximeter, invasive blood pressure monitoring, rectal temperature probe, and end-tidal capnography. At the end of surgery, patients were weaned from CPB in a stepwise fashion. Respiratory ETCO2 and in-line venous oximetry were continuously monitored during weaning. The ETCO2 was recorded at quarter pump flow and after complete weaning from CPB. Following weaning from CPB, CO was measured by thermodilution. The CO values were correlated with the ETCO2 during partial bypass and following weaning from bypass. Regression analysis of ETCO2 at quarter-flow and post-bypass CO showed significant correlation (r = 0.57, p 30 mm Hg during partial CPB will always predict an adequate CO following weaning from CPB. An ETCO2 <30 mm Hg may denote either a low or a normal cardiac output and hence other predictive parameters such as SvO2 must be added