Background There are few studies to assess whether the effect-site concentration of propofol can predict anesthetic depth during the target-controlled infusion (TCI) induction in elderly patients. This study aimed t...Background There are few studies to assess whether the effect-site concentration of propofol can predict anesthetic depth during the target-controlled infusion (TCI) induction in elderly patients. This study aimed to evaluate the relationship between effect-site concentration of propofol and depth of anesthesia during the TCI induction in elderly patients. Methods Ninety patients (60-80 years) with an American Society of Anesthesiologists (ASA) physical status of 1-3, undergoing scheduled abdominal and thoracic surgery under general anesthesia were randomly allocated into one of three groups, Group S1, S2 and S3 (30 patients in each group). The patients in Group S1 received propofol with a target plasma concentration of 4.0 pg/ml; patients in Group S2 received propofol with an initial target plasma concentrations of 2.0 IJg/ml that was raised to 4.0 pg/ml 3 minutes later; patients in Group S3 received an infused scheme of 3 steps; starting from a target plasma concentration of 2.0 pg/ml that was increased stepwised by 1 pg/ml until a target plasma concentration of 4.0 pg/ml was achieved, the interval between the two steps was 3 minutes. When an Observer's Assessment of Alertness/Sedation (OANS) score of 1 was achieved, remifentanil (effect-site concentration (Ce) of 4.0 ng/ml) and rocuronium 0.9 mg/kg were administered. Tracheal intubation was started 2 minutes after rocuronium injection. Changes of propofol Ce, blood pressure (BP), heart rate (HR), and bispectral index (BIS) were recorded. Results When an OAA/S score of 1 was achieved, Ce of propofol were (1.7±0.4) pg/ml, (1.9±0.3) pg/ml, (1.9±0.4) pg/ml and the BIS values were 64±5, 65±8, and 62±8 in Groups S1, S2 and S3. Before intubation, Ce of propofol was (2.8±0.2) pg/ml, (2.8±0.3) pg/ml, (2.7±0.3) pg/ml, and the BIS values were 48±7, 51±7, and 47±5 in Groups S1, S2 and S3. By linear regression analysis, a significant correlation between Ce of propofol and BIS values was found (展开更多
文摘Background There are few studies to assess whether the effect-site concentration of propofol can predict anesthetic depth during the target-controlled infusion (TCI) induction in elderly patients. This study aimed to evaluate the relationship between effect-site concentration of propofol and depth of anesthesia during the TCI induction in elderly patients. Methods Ninety patients (60-80 years) with an American Society of Anesthesiologists (ASA) physical status of 1-3, undergoing scheduled abdominal and thoracic surgery under general anesthesia were randomly allocated into one of three groups, Group S1, S2 and S3 (30 patients in each group). The patients in Group S1 received propofol with a target plasma concentration of 4.0 pg/ml; patients in Group S2 received propofol with an initial target plasma concentrations of 2.0 IJg/ml that was raised to 4.0 pg/ml 3 minutes later; patients in Group S3 received an infused scheme of 3 steps; starting from a target plasma concentration of 2.0 pg/ml that was increased stepwised by 1 pg/ml until a target plasma concentration of 4.0 pg/ml was achieved, the interval between the two steps was 3 minutes. When an Observer's Assessment of Alertness/Sedation (OANS) score of 1 was achieved, remifentanil (effect-site concentration (Ce) of 4.0 ng/ml) and rocuronium 0.9 mg/kg were administered. Tracheal intubation was started 2 minutes after rocuronium injection. Changes of propofol Ce, blood pressure (BP), heart rate (HR), and bispectral index (BIS) were recorded. Results When an OAA/S score of 1 was achieved, Ce of propofol were (1.7±0.4) pg/ml, (1.9±0.3) pg/ml, (1.9±0.4) pg/ml and the BIS values were 64±5, 65±8, and 62±8 in Groups S1, S2 and S3. Before intubation, Ce of propofol was (2.8±0.2) pg/ml, (2.8±0.3) pg/ml, (2.7±0.3) pg/ml, and the BIS values were 48±7, 51±7, and 47±5 in Groups S1, S2 and S3. By linear regression analysis, a significant correlation between Ce of propofol and BIS values was found (