ABSTRACT
Objective To explore the effect of dexmedetomidine on blood coagulation following radical gastrectomy.Methods ASA Ⅰ or Ⅱ patients aged 51-70 years weighing 53-75 kg scheduled for radical gastrectomy were randomly allocated to two groups:dexmedetomidine group (group D)and control group (group C).Dexmedetomidine 0.5 μg/kg was intravenously infused over 10 minutes before anesthesia induction,followed by a rate of 0.5 μg·kg-1 ·h-1 until peritoneal closure in group D and volume-matched normal saline was administrated in group C.Radical gastrectomy was performed under total intravenous anesthesia with propofol and remffentanil.A series of warming measures were implemented and artificial colloid and heparin flushing fluid were not used.Postoperative patient-controlled intravenous analgesia was performed to maintain visual analogue scale≤3.The blood samples were collected for TEG and standard coagulation monitoring before dexmedetomidine and saline administration and 3 h after surgery.Results The temperature and hematocrit in the postoperative period were significantly less than the preoperative period in two groups (P＜0.01).In both groups,the activity of plasma antithrombin Ⅲ was significantly decreased and the concentration of plasma FDP was significantly increased in the postoperative period when compared with the preoperative period (P ＜0.01).In group D,the R time was significantly shortened and MA value was significantly increased in the postoperative period when compared with the preoperative period (P＜0.05) and there were no significant differences in the K time and α angle between the preoperative and postoperative period.In group C,the R and K time were significantly shortened and the value for MA and α angle were significantly increased in the postoperative period compared with the preoperative period (P＜0.01).The platelet counts,PT,APTT,and plasma fibrinogen concentration were comparable between the preoperative and postoperative period in both groups.The requirements of propofol and remifentanil in group D were significantly less than group C (P＜0.05).In the preoperative period,the plasma antithrombin Ⅲ activity,FDP concentration,and the values for all TEG variables were similar in both groups.In the postoperative period,the value for MA and the concentration of plasma FDP in group D were less than that in group C and the value for R and the activity of plasma AT Ⅲ in group D were more than group C (P＜0.05 or P＜0.01) and there were no significant differences in the K time and α angle in both groups.There were no significant differences in the temperature,hematocrit,platelet counts,PT,APTT,and plasma fibrinogen concentration in the preoperative and postoperative periods between the two study groups.Conclusion Adjunctive dexmedetomidine in general anesthesia could inhibit the decrease of R time and raise of the value for MA,inhibit the decrease of plasma an tithrombin Ⅲ activity and raise of FDP concentration,which indicated that dexmedetomidine can improve blood coagulation state after radical gastrectomy.
ABSTRACT
Objective To determine the optimal pressure for facemask ventilation during induction of general anesthesia by real-time ultrasonographic measurement of antral cross-sectional area (CSA) in adult patients.Methods Sixty American Society of Anesthesiologists physical status Ⅰ or Ⅱ patients,aged 18-60 yr,with body mass index of 20-25 kg/m2,scheduled for elective operation under general anesthesia,were divided into 5 groups (n=12 each) using a random number table:P10 group,P13 group,P16 group,P19 group and P22 group.After induction of anesthesia,an oropharyngeal airway was inserted,and the patients were ventilated for a 2-min period in a pressure-controlled mode using the two-handed mask ventilation technique.The pressure for facemask ventilation was 10,13,16,19 and 22 cmH2O in P10,P13,P16,P19 and P22 groups,respectively.The antral CSA was measured using real-time ultrasonography before and after facemask ventilation.Respiratory parameters were recorded.Results Compared with group P1O,the number of patients in whom CSA＜340 mm2 after facemask ventilation was significantly decreased in P16,P19 and P22 groups,and the number of patients in whom the tidal volume ≥ 6 ml/kg was increased in P13,P16,P19 and P22 groups (P＜ 0.01).The number of patients in whom optimnal pressure for facemask ventilation was achieved was 2,10,6,4 and 1 in P10,P13,P16,P19 and P22 groups,respectively,with the most cases in group P13 (P ＜ 0.01).Conclusion The optimal pressure is 13 emH2O for facemask ventilation during induction of general anesthesia when determined by realtime ultrasonographic measurement of antral CSA,and it can ensure adequate oxygen supply and reduce gastric insufflation in adult patients.