Comparison of Cost-Effectiveness of Propofol Using Target-Controlled Infusion (TCI) with Standard Anesthesia Regimens in Major Operations / 대한마취과학회지

BACKGROUND: The purpose of this study was to compare the cost-effectiveness of propofol using a target-controlled infusion (TCI) with two currently used anesthetic regimens during major operations. METHODS: Forty-two patients undergoing major gynecological surgery were divided into three groups according to the period during which the surgeries were performed. Group propofol/TCI (n = 16) received 1% propofol using TCI-50% N2O, Group isoflurane (n = 14) received thiopental 5 mg/kg-isoflurane-50% N2O, and Group enflurane (n = 12) received thiopental 5 mg/kg-enflurane-50% N2O. All patients also received 2 microgram/kg of fentanyl before induction. Concentrations of propofol and volatile anesthetics were varied according to the patient's hemodynamic responses. Consumption of volatile anesthetics was measured by weighing the vaporizers by a precision weighing machine. RESULTS: Biometric data, duration of surgery and of anesthesia were similar in the three groups. Recovery from anesthesia was significantly shorter in the propofol/TCI group. Episodes of postoperative nausea and vomiting in the recovery room were less common in propofol/TCI group. Patient satisfaction was similar in all three groups. Total (intra- and postoperative) costs were significantly higher in the propofol/TCI group. CONCLUSIONS: When compared with the standard anesthetic regimens, the use of propofol using TCI anesthesia during major operations was associated with higher costs, but did not offer any clinically significant advantages in cost-effectiveness over the standard anesthesia regimens.

The Effect of Clonidine Added to Bupivacaine on Intercostal Nerve Block for Postoperative Pain Control / 대한마취과학회지

BACKGROUND: The addition of clonidine to local anesthetics for regional block has been shown to increase the duration of anesthesia and analgesia. This study was designed to determine whether the addition of clonidine to bupivacaine would produce an extension of the analgesic effect after intercostal nerve block (ICNB). METHODS: After informed consent, 30 ASA 1 or 2 patients undergoing appendectomy under general anesthesia were randomly divided into two groups. Before induction of anesthesia, ICNB using a posterior approach was performed with 15 ml of 0.25% bupivacaine plus epinephrine 1:200,000 with (Group BEC; n = 15) or without (Group BE; n = 15) clonidine 75 microgram. Analgesia was assessed by cold testing at 1/min intervals until cold sensation decreased. The duration of analgesia (time between injection and onset of pain) was recorded. We also recorded the visual analogue scale (VAS) of pain, the number of supplemental analgesics, heart rate and blood pressure, and side effects over 24 hours postoperatively. RESULTS: The onset time, duration of analgesia, number of analgesics, and heart rate and blood pressure were comparable in both groups. VAS scores were significantly lower in Group BEC than in Group BE at 12, 16, and 20 hours postoperatively. CONCLUSIONS: The addition of clonidine to bupivacaine with epinephrine may be a useful adjunct and can prolong the duration of analgesia after ICNB without significant side effects.

Comparision of Hemodynamic Changes in Patients Undertaking Hysterectomies under Genernal and Epidural Anesthesia / 대한마취과학회지

BACKGROUND: The purpose of the study was to evaluate the effect of postural change on hemodynamics using thoracic eletrical bioimpedance (TEB) device during general anesthesia with enflurane-N2O-O2 and lumbar epidural anesthesia. The TEB device is safe, reliable and non-invasive way to measure hemodynmic values continuously. METHODS: General anesthesia (twenty patients) was induced by administration of pentotal sodium 5 mg/kg and succinylcholine 1 mg/kg intravenously, and was maintained with 1 vol% of enflurane, N2O-O2 (2 l/min-2 l/min) and vecuronium 0.1 mg/kg. Epidural anesthesia (twenty patients) was performed at the level of L3-4 epidural space using 20 ml of 2% xylocaine mixed with epinephrine (5 microgram/ml). Hemodynamic changes were measured before induction, 1 and 5 minutes after intubation or epidural injection, 1, 5, 10, 20, 30 minutes after head- down tilt and 1, 5, 10 minutes after returning to the supine position. RESULTS: HR and LVSWI were minimaly affected in group E with epidural anesthesia compared to group G with general anesthesia. BP (SBP, DBP, MAP) and SVRI were remarkably increased in group G compared to group E. BP and SVRI showed rapid increse 1 minutes after head-down tilt in group G (p<0.01) and decreased gradually thereafter. SI and CI were decreased significantly in group G compared to group E (p<0.001). SI was unchanged but CI was decreasd significantly after head-down tilt in group E (p<0.05). EDI and ACI showed lower values decreased in general significantly in group G compared to group E (p<0.05). CONCLUSIONS: All hemodynamic changes were more predictable, gradual, less variable, and stable in the group with epidural anesthesia compared to the group with general anesthesia for hysterectomy.

Carboxyhemoglobin Levels during High and Minimal Flow Anesthesia / 대한마취과학회지

BACKGROUND: Minimal flow anesthesia preserves the moisture content of CO2 absorbents and seems to be a factor inhibiting carbon monoxide generation. In order to assess the safety of minimal flow anesthesia, we studied carboxyhemoglobin (COHb) level in minimal flow anesthesia. METHODS: Forty women, ASA physical status I or II, undergoing total abdominal hysterectomy were randomly allocated to one of two groups with N2O-enflurane anesthesia. Anesthesia was maintained with O2 2 l/min and N2O 2 l/min (group 1) or O2 0.3 l/min and N2O 0.2 l/min (group 2). The arterial COHb levels were measured immediately after induction (T1), 45 min after induction (T2), 75 min after induction (T3), and after recovery from anesthesia (T4). RESULTS: Although there was no statistically significant change in both groups, the COHb level at T3 and T4 increased more than that at T1 in group 1, and that at T3 and T4 decreased more than that at T1 in group 2. There was a significant difference in the COHb level at T4 between group 1 (0.93 0.31%) and 2 (0.68 0.36%) (P <0.05). CONCLUSIONS: These results show that minimal flow anesthesia does not increase the COHb level and may be performed safely.

Comparison of Hemodynamic Changes by the Thoracic Electrical Bioimpedance Device during Endotracheal Intubation or Insertion of Laryngeal Mask Airway in General Anesthesia / 대한구급학회지

Introduction: we measured the hemodynamic changes by the thoracic electrical bioimpedance (TEB) device during induction of anesthesia, endotracheal intubation or insertion of layngeal mask airway (LMA). This TEB device is safe, reliable and estimate continuously and invasively hemodynamic variables. METHODS: We measured the cardiovascular response of endotracheal intubation or that of LMA insertion in thirty ASA class I patients. General anesthesia was induced with injection of fentany 1 microgram/kg, thiopetal sodium 5 mg/kg and vecuronium 1 mg/kg intravenously. Controlled ventilation was for 3 minutes with inhalation of 50% nitrous oxide and 1.5 vol% of enflurane before tracheal intubation or LMA insertion in all patients. The patient was randomly assinged to either tracheal intubation group (ET group) or laryngeal mask airway group (LMA group). Heart rate (HR), mean arterial pressure (MAP), systemic vascular resistance (SVR), stroke index (SI) and cardic index (CI) were measured to pre-induction, pre-intubation, 1 minute after intubation, 2 minute, 3 minute, 5 minute, 7 minute. RESULTS: MAP and SVR were decreased effectively LMA group than ET group during 1 minute after intubation, 2 minute, 3 minute, 5 minute, 7 minute (p<0.05). HR was decreased effectively LMA group than ET group between pre-induction and 1 minute after intubation, between 1 minute after intubation and 2 minute after intubation (p<0.05). But, SI and CI were no difference between ET group and LMA group during induction of anesthesia and intubation (p<0.05). CONCLUSION: The insertion of LMA is beneficial for certain patients than endotracheal tube to avoid harmful cardiovascular response in the management of airway during anesthesia.