The Effect of SCD Response Compression System on Coagulation and Fibrinolysis using Thromboelastography in Patients Undergoing Gastrectomy; a Comparison with Elastic Stocking / 대한마취과학회지

BACKGROUND: Among various measures to prevent deep venous thrombosis (DVT) in surgical patients, intermittent pneumatic compression of the legs is known to be effective without increasing the risk of bleeding. In this study, the coagulation/ fibrinolysis profile in patients undergoing gastrectomy with SCD Response Compression System, which detects individual venous refill time, was compared to that with elastic stocking using thromboelastography (TEG). METHODS: Fifty-eight ASA class I-II patients undergoing gastrectomy were randomized into two groups. Patients in ES group (n = 29) were treated with elastic stocking and patients in SCD group (n = 29) were treated with SCD Response Compression System. TEG analysis and traditional coagulation tests were performed on arrival in the operating room, after surgery in the postanesthetic care unit and on the morning of postoperative day 1. RESULTS: There was no significant difference in laboratory data between the two groups. Laboratory data at all time points were within normal limit in all patients. There was no significant difference in TEG data between the two groups. No evidence of a postoperative clinical coagulopathy (DVT or pulmonary embolism) was observed on routine history and physical examinations in any patient during hospitalization. CONCLUSIONS: The effectiveness of SCD Response Compression System in patients undergoing major abdominal surgery on coagulation/fibrinolysis system was similar to that of elastic stocking during perioperative period.

Effects of Varying Concentrations of Enflurane on Respiratory System Mechanics in Cats / 대한마취과학회지

BACKGROUND: Flow interruption technique has been used to measure respiratory system mechanics, and its prominent advantage is to partitionate the respiratory system resistance into airway and tissue component. In this study, we investigated the effects of varing concentrations of enflurane on respiratory system mechanics using flow interruption technique. METHODS: Six cats, weighing 3.0~3.6 kg were used. Pentobarbital sodium was injected intraperitonially and endotracheal intubation was followed. Intermittent mandatory ventilation was applied with Siemens Servo 900C ventilator. The inspiratory flow rate, tidal volume, and respiratory rate were fixed, and normocarbia (PaCO2; 30~35 mmHg) was maintained throughout the experiment. The changes in the pressure and volume were recorded with Bicore CP100 pulmonary monitor at control, 0.5, 1, 1.5, and 2 MAC of enflurane. The data were transfered to a PC and analyzed by Anadat processing software. Respiratory system, airway and tissue viscoelastic resistances, and dynamic and static compliances were calculated. RESULTS: Respiratory system resistances decreased up to 1 MAC of enflurane compared to the control value (p<0.05), but there were no significant differences in the values of resistance among 1, 1.5, 2 MAC of enflurane. There were no significant differences in tissue viscoelastic resistances, and dynamic and static compliances with varying concentrations of enflurane. CONCLUSIONS: Enflurane significantly reduces the respiratory system resistance mainly by decreasing airway resistance. Tissue viscoelastic resistance and respiratory system compliances are not influenced by changes in concentration of enflurane.

The Difference between Arterial and End-tidal Carbon Dioxide Tension in Anesthetized Patients with Reduced Functional Residual Capacity / 대한마취과학회지

BACKGROUND: It has been known that arterial carbon dioxide tension is 4~5 mmHg higher than end-tidal carbon dioxide tension in healthy adults during general anesthesia. But negative arterial to end-tidal PCO2 difference was reported in pregnant patients undergoing cesarean section. The purpose of this study was to elucidate the difference between arterial and end-tidal PCO2 in anesthetized patients with reduced functional residual capacity. METHODS: 90 patients were divided into 3 groups i.e. control group (n=30), obese group (n=20, body weight more than 20% greater than ideal weight), pregnant group (n=40). All patients had no cardiac or respiratory abnormalities and never smoked. Arterial blood gas analysis and measurement of end-tidal PCO2 were done 20 minutes after induction of anesthesia in control and obese group and just before uterine incision and 20 minutes after fetal delivery in pregnant group. RESULTS: There were significant correlations between arterial and end-tidal PCO2 in all groups. The incidences of negative arterial to end-tidal PCO2 difference were 10% in control group, 40% in obese group, 42.5% in pregnant group (p<0.05). CONCLUSION: From this study, it is concluded that patients with reduced functional residual capacity have more incidences of negativity than normal patients in the values of arterial to end-tidal PCO2 difference during general anesthesia. So when the tight control of PaCO2 is required in patients with reduced FRC, we recommend to measure PaCO2 for better anesthetic management.