In Response

Abstract

In Response We agree with Malherbe and Ansermino that the required doses of propofol vary among patients over a wide dose range.1 We only listed the commonly used doses when combined with topical 1% lidocaine sprayed on the surface of the vocal cords and trachea. Regarding the dose of remifentanil, it was 0.1 μg/kg/min, and the larger dose suggested by Malherbe and Ansermino would cause respiratory depression in our patients, perhaps because of the inter-racial or interproduct differences. Our study2 had 2 major objectives: first, to determine the surgical outcomes and perioperative adverse events associated with the ventilation modes and anesthetic protocols; second, to identify risk factors statistically correlated with intraoperative or postoperative hypoxemia. The most frequent adverse event was found to be hypoxemia. The risk factors correlated with hypoxemia were patient age, type of foreign body, duration of surgery, pneumonia, and ventilation mode. In addition, however, we did acknowledge in the discussion section the possibility suggested by Malherbe and Ansermino1 that the relatively higher rate of body movement in the total IV anesthesia group might be attributable to the inadequate depth of anesthesia, and the relatively higher failure rate of foreign body removal might be partly attributable to the non-ideal surgical condition in the total IV anesthesia group.2 However, because the logistic regression analysis did not reveal a correlation between the doses of drugs to the occurrence of hypoxemia, we did not include the dose of drugs as a risk factor. Lian-hua Chen, MD, PhD Department of Anesthesiology The Eye, Ear, Nose and Throat Hospital Fudan University Shanghai, China Tian-yu Zhang, MD, PhD Department of Otolaryngology The Eye, Ear, Nose and Throat Hospital Fudan University Shanghai, China [email protected]