ABSTRACT
BACKGROUND: We investigated effect-site concentrations of propofol, changes in blood pressure and heart rate, time to loss of consciousness, time to loss of eyelid reflex and awakening time during anesthesia using effect-site target-controlled infusion, to compare the differences between Schnider and modified Marsh model. METHODS: Forty American Society of Anesthesiologists (ASA) physical status I or II patients between the ages of 18 and 55 years old and who were scheduled for elective surgery under general anesthesia were enrolled in this study. The patients were randomized into two groups: one group using modified Marsh model (Group 1) and the other group using Schnider model (Group 2). Effect-site concentrations of propofol, blood pressure, heart rate and BIS at each anesthetic stage were recorded. Time to loss of consciousness, time to loss of eyelid reflex and awakening time were measured. RESULTS: Group 1 showed shorter time to loss of consciousness and eyelid reflex at the lower effect-site concentration of propofol than Group 2 (P < 0.05). The effect-site concentrations of Group 1 were higher than those of Group 2 at eye opening and extubation (P < 0.05). CONCLUSIONS: Induction of anesthesia is achieved at lower effect-site concentration of propofol and more rapidly in the modified Marsh model than in the Schnider model. However the effect-site concentrations of propofol for awakening are higher in the modified Marsh model than in the Schnider model.
Subject(s)
Humans , Anesthesia , Anesthesia, General , Blood Pressure , Eye , Eyelids , Heart Rate , Propofol , Reflex , Unconsciousness , WetlandsABSTRACT
BACKGROUND: The sniffing position is recommended for conventional laryngeal mask airway (LMA) insertion. However, there has been a high success rate of LMA insertion with the head in the neutral position. The effect of a difficult airway on the ease of LMA insertion is not clear. In this study, we compared the ease of LMA ProSeal(TM) (PLMA) insertion and the fiberoptic scoring according to the head position and the presence of a difficult airway. METHODS: After obtaining informed consent from the subjects, we enrolled 144 adult patients (age range: 18-65) with an ASA physical status 1 or 2. After evaluation of the airway, all the patients were grouped into the EA (easy airway) group (n = 68) and the DA (difficult airway) group (n = 76). According to the head position, each group was divided into the EA-SE (extension) group (n = 35), the EA-SN (sniffing) group (n = 33), the DA-SE group (n = 39) and the DA-SN group (n = 37). The success rate and insertion time at the first attempt were evaluated. The position of the PLMA was fiberoptically scored from the mask aperture of the airway tube in the original head position. After the head position was changed to the sniffing and neutral positions in the SE and SN group, respectively, the position of PLMA was re-evaluated fiberoptically. RESULTS: The success rate and insertion time at the first attempt and the fiberoptic score showed no significant difference among the groups. After head position was changed, there were no significant changes in the fiberopitc scores. CONCLUSIONS: A difficult airway and the head position had no influence on the ease of PLMA insertion and the fiberopic score. Therefore, the head position can be selected according to the individual patient's situation.
Subject(s)
Adult , Humans , Head , Informed Consent , Laryngeal Masks , MasksABSTRACT
Fat embolism syndrome is a rare and potentially lethal complication most commonly seen in long bone fractures and intramedullary manipulation. The clinical triad of fat embolism syndrome consists of mental confusion, respiratory distress, and petechiae. This study reports a case of cerebral fat embolism syndrome following elective bilateral total knee replacement. After an uneventful anesthesia and initial recovery, the patient developed neurologic symptoms nine hours postoperatively.