ABSTRACT
<p><b>BACKGROUND</b>Awareness is a serious complication of general anesthesia. In China, the incidence of intraoperative awareness was 1% in patients undergoing total intravenous anesthesia (TIVA). In this study, we compared the incidence of awareness between Bispectral index (BIS)-guided and routine TIVA protocol and evaluated the effect of BIS on preventing awareness.</p><p><b>METHODS</b>A prospective, randomized, double-blinded, multicenter controlled trial was performed. Patients (≥ 18 years of age) undergoing TIVA were randomly divided into BIS-guided group (Group A, BIS was monitored and recommended to maintain between 40 - 60) and control group (Group B, BIS was monitored but the screen was covered). The intraoperative BIS values were downloaded and the BIS trends of confirmed awareness cases were analyzed to determine whether light anesthesia existed.</p><p><b>RESULTS</b>Of the total 5228 patients, 2919 patients were assigned to Group A and 2309 to Group B. Four cases of confirmed awareness (0.14%) were reported in the BIS-guided group and 15 (0.65%) in the control group (P = 0.002, OR = 0.21, 95% confidence intervals: 0.07 - 0.63). The incidence of possible awareness (0.14% vs. 0.26%, P = 0.485) and dreaming (3.1% vs. 3.1%, P = 0.986) was comparable between BIS-guided group and the control group. Among the 19 confirmed awareness cases, intraoperative BIS trends of six cases were downloaded and identified. Five of them showed signs of light anesthesia as BIS > 60 and lasted 19 - 106 minutes, whereas one case had a stable BIS trend and the values were within 60 during the operation. Another five awareness cases were reviewed for anesthesia procedures, of which improper light anesthesia were confirmed.</p><p><b>CONCLUSIONS</b>BIS-guided TIVA (BIS was recommended to maintain between 40 - 60) decreased the risk of awareness compared with routine TIVA. The main reason for awareness was light anesthesia.</p>
Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Anesthesia, General , Methods , Anesthesia, Intravenous , Methods , Intraoperative AwarenessABSTRACT
<p><b>OBJECTIVE</b>To observe the effects of acute normovolemic hemodilution (ANH) on coagulation function and fibrinolysis in elderly patients undergoing hepatic carcinectomy.</p><p><b>METHODS</b>Thirty elderly patients (aged 60-70 years) with liver cancer (American Society of Anesthesiologists physical status I-II) scheduled for hepatic carcinectomy from February 2007 to February 2008 were randomly divided into ANH group (n = 15) and control group (n = 15). After tracheal intubation, patients in ANH group and control group were infused with 6% hydroxyethyl starch (HES) (130/0.4), and basic liquid containing 6% HES and routine Ringer's solution, respectively. In all the studied patients, blood samples were drawn at five different time points: before anesthesia induction (T1), 30 minutes after ANH (T2), 1 hour after start of operation (T3), immediately after operation (T4), and 24 hours after operation (T5). Then coagulation function, soluble fibrin monomer complex (SFMC), prothrombin fragment (F1+2), and platelet membrane glycoprotein (activated GPIIb/GPIIIa and P-selectin) were measured.</p><p><b>RESULTS</b>The perioperative blood loss was not significantly different between the two groups (P > 0.05). The volume of allogeneic blood transfusion in ANH group was significantly smaller than that in control group (350.5 +/- 70.7 mL vs. 457.8 +/- 181.3 mL, P < 0.01). Compared with the data of T1, prothrombin time (PT) and activated partial thromboplastin time in both groups prolonged significantly after T3 (P < 0.05), but still within normal range. There were no significant changes in thrombin time and D-dimer between the two groups and between different time points in each group (all P > 0.05). SFMC and F1 + 2 increased in both groups, but without statistical significance. P-selectin expression on the platelet surface of ANH group was significantly lowered at T2 and T3 compared with the level at T1 (P < 0.05). Compared with control group, P-selectin was significantly lower in ANH group at T2-T5 (all P < 0.05).</p><p><b>CONCLUSIONS</b>In elderly patients undergoing resection of liver cancer, ANH may not hamper fibrinolysis and coagulation function. It could therefore be safe to largely reduce allogeneic blood transfusion.</p>