Aim: To compare the safety and efficacy of carbon dioxide (CO2) and air insufflation during gastric endoscopic submucosal dissection (ESD).
Methods: This study involved 116 patients who underwent gastric ESD between January and December 2009. After eliminating 29 patients who fit the exclusion criteria, 87 patients, without known pulmonary dysfunction, were randomized into the CO2 insufflation (n = 36) or air insufflation (n = 51) groups. Standard ESD was performed with a CO2 regulation unit (constant rate of 1.4 L/min) used for patients undergoing CO2 insufflation. Patients received diazepam for conscious sedation and pentazocine for analgesia. Transcutaneous CO2 tension (PtcCO2) was recorded 15 min before, during, and after ESD with insufflation. PtcCO2, the correlation between PtcCO2 and procedure time, and ESD-related complications were compared between the two groups. Arterial blood gases were analyzed after ESD in the first 30 patients (12 with CO2 and 18 with air insufflation) to assess the correlation between arterial blood CO2 partial pressure (PaCO2) and PtcCO2.
Results: There were no differences in respiratory functions, median sedative doses, or median procedure times between the groups. Similarly, there was no significant difference in post-ESD blood gas parameters, including PaCO2, between the CO2 and air groups (44.6 mmHg vs 45 mmHg). Both groups demonstrated median pH values of 7.36, and none of the patients exhibited acidemia. No significant differences were observed between the CO2 and air groups with respect to baseline PtcCO2 (39 mmHg vs 40 mmHg), peak PtcCO2 during ESD (52 mmHg vs 51 mmHg), or median PtcCO2 after ESD (50 mmHg vs 50 mmHg). There was a strong correlation between PaCO2 and PtcCO2 (r = 0.66; P < 0.001). The incidence of Mallory-Weiss tears was significantly lower with CO2 insufflation than with air insufflation (0% vs 15.6%, P = 0.013). CO2 insufflation did not cause any adverse events, such as CO2 narcosis or gas embolisms.
Conclusion: CO2 insufflation during gastric ESD results in similar blood gas levels as air insufflation, and also reduces the incidence of Mallory-Weiss tears.
Keywords: Carbon dioxide; Gastric endoscopic submucosal dissection; Insufflation; Mallory-Weiss tear; Randomized controlled trial.