Search

Background: The aim of this study is to investigate the characteristics of propofol abuse based on the results of a survey analysis of abusers among non-healthcare professionals in Korea. Methods: Thirty-eight propofol abusers were questioned between October and December 2010, and were enrolled and voluntarily participated in a structured survey consisting of an interview and completing a previously prepared questionnaire. The questionnaire was divided into three distinct parts: part 1 dealt with the history of propofol abuse; part 2 highlighted the problems caused by propofol abuse; and part 3 enquired regarding demographics of abusers. Results: Thirty-one (81.6%) of the 38 interviewees abused propofol for more than one year. During the last 12 months, 34 (89.0%) received propofol at two or three times a week. The minimum and maximum amounts of propofol (median, range) administered each time were 500 (100, 1000) and 2000 (500, 4000) mg, respectively. Stress relief and the maintenance of a sense of well-being were quoted the most important reasons for the first-time administration of propofol and its subsequent abuse, respectively. The majority of abusers (36.0, 97.3%) reported a sense of pleasure or euphoria at the time of their propofol injection. Withdrawal symptoms occurred in five abusers (13.2%). Thirteen (36.1%) reported disruptions in their work life. None of the respondents had previously admitted to and or reported abuse of any other controlled substances. Conclusions: These results provided reference data for the regulation of propofol in Korea as a controlled substance and may also be of interest to international agencies in other countries.

Background: Lidocaine has been used widely to prevent propofol injection pain. Various methods of administration exist, such as lidocaine premixed with propofol or lidocaine pretreatment using a tourniquet, but it is unclear which method of lidocaine administration is more effective for the prevention of injection pain of propofol LCT/MCT. The purpose of this study was to compare pretreatment of lidocaine with a tourniquet and a premixed injection of lidocaine to prevent injection pain of propofol-LCT/MCT. Methods: Patients were randomly allocated into the pretreatment group (n = 117) or the premixed group (n = 117). The pretreatment group was pretreated with 2 ml of lidocaine 2%, held with a tourniquet, before propofol-LCT/MCT injec tion. The premixed group was injected with a premixed solution of propofol-LCT/MCT and 2 ml of lidocaine 2%. To evaluate the incidence and severity of pain, spontaneous verbal expressions of pain, movement of hand, frowning, and moaning were recorded, and the patients were asked to recall their pain with the visual analogue score (VAS) 30 minutes after awakening from anesthesia. Results: Overall, injection pain occurred in 13.7% of the pretreatment group and 15.4% of the premixed group, without any statistical difference (P = 0.71). There was no difference in spontaneous verbal expressions of pain, movement of hand, frowning, and moaning between the two groups. The pain intensity (VAS) also showed no difference between the two groups (P = 0.49). Conclusions: Pretreatment of lidocaine with a tourniquet showed no more benefit to prevent injection pain of propofol LCT/MCT compared to a premixed injection with lidocaine. (Korean J Anesthesiol 2014; 66: 95-98)

Background: Propofol injection pain is an unpleasant experience to patients and its prevalence can be influenced by age and gender. We determined the half maximal effective concentration (EC 50) of remifentanil for preventing the microemulsion propofol injection pain in the male and female adult groups. Methods: After institutional review board approval, a total of 60 patients were assigned into 2 groups depending on their gender: group M (male, 20-65 yr) and group F (female, 20-65 yr). Anesthesia was induced with propofol and remifentanil, by a target-controlled infusion. Target effect-site concentration (Ce) of propofol and remifentanil for the first patient started at 4.0 ug/ml and 4.0 ng/ml. Ce of remifentanil for each subsequent patient was determined by the response of the previous patient by the Dixon's up-and-down method (DUDM) with an interval of 0.2 ng/ml. After equilibration of plasma and effect site remifentanil concentration, propofol was administered, and the pain responses were observed. Results: The remifentanil EC 50 was 3.8 ± 0.2 and 2.7 ± 0.2 ng/ml in groups M and F, respectively, by DUDM. From Probit regression model, the remifentanil EC50 was 3.7 (3.0-4.3) and 2.7 (1.8-2.9) ng/ml in groups M and F, respectively. Conclusions: The remifentanil EC 50 for preventing the moderate to severe injection pain of propofol was higher in males than in females. (Korean J Anesthesiol 2012; 63: 504-509)

Background: A microemulsion propofol causes a high incidence of pain during intravenous injection. In this study, we investigated the effect of ramosetron on pain induced by microemulsion propofol injection. Methods: After prospective power analysis and institutional review board approval, a total of 200 ASA I and II patients undergoing general anesthesia were divided into 4 groups. They received one of the following intravenously after tourniquet application on the forearm 1 min before induction of anesthesia using microemulsion propofol; normal saline (Group N, n = 50), lidocaine 20 mg (Group L, n = 50), ramosetron 0.3 mg (Group R, n = 50) and lidocaine 20 mg plus ramosetron 0.3 mg (Group LR, n = 50) diluted into a 5 ml solution. The occlusion was released after 30 seconds and microemulsion propofol was injected over 10-15 seconds. The patients were observed and asked immediately if they had pain in the arm, and their responses were assessed. Results: The incidence of pain in groups N, L, R and LR was 96%, 76%, 60% and 38%, respectively (P < 0.008). Two patients in Group LR (4.0%) and nine in Group R (18.0%) had moderate to severe pain, which was significantly lower than pain in Groups N (84.0%), L (40.0%) and R (P < 0.008). Conclusions: Pretreatment with ramosetron 0.3 mg with or without lidocaine 20 mg with a tourniquet on the forearm 30 seconds before the injection of microemulsion propofol is more effective than lidocaine 20 mg or normal saline in preventing pain from a microemulsion propofol injection. (Korean J Anesthesiol 2011; 61: 30-34)

Background: Propofol produces anesthesia with rapid recovery but also causes pain on injection. This study was designed to evaluate the effects of two different concentrations of remifentanil for minimizing the pain caused by propofol and to compare the hemodynamic changes during propofol-remifentanil infusion. Methods: In a randomized, double-blind study of 80 patients, we compared the severity of the injection pain of propofol between two groups of patients. The initial effect-site target concentration of remifentanil was set at 4 ng/ml (the R4 group, n = 40) or 8 ng/ml (the R8 group, n = 40). After the effect-site concentration of remifentanil was achieved, the infusion of propofol was started with the concentration of 4 μg/ml. The remifentanil-related complications were evaluated and the severity of the pain caused by propofol was compared by using a four-point scale during the propofol infusion. The heart rate and arterial blood pressure were measured at pre-induction, just before intubation and at 1 minute after intubation. Results: The severity of injection pain of propofol was significantly lower in the R8 group than in the R4. There was no significant difference in the incidence of remifentanil-related complications between the two groups. Compared with the pre-induction values, the heart rate and arterial blood pressure were significantly lower at pre-intubation and at 1 minute after intubation in the R4 and R8 groups. Conclusions: Pretreatment with an effect-site concentration of 8 ng/ml remifentanil may be useful for minimizing the propofol injection pain compared with 4 ng/ml remifentanil. (Korean J Anesthesiol 2009; 57: 155∼60)

The temporomandibular joint can be dislocated during anesthesia as a result of excessive oral opening and direct laryngoscope handling. Occasionally, yawning can be observed during the induction of anesthesia with propofol. The forceful and voluntary yawning after a propofol injection can lead to a dislocation of the temporomandibular joint. We report a case of an anterior dislocation of the temporomandibular joint upon induction with propofol, which caused difficulties in mask ventilation and endotracheal intubation. Although intubation had been carried out successfully in this case, an unanticipated difficult airway can be confronted at anytime. Therefore, anesthesiologists should be aware of the management of a difficult airway and practice various methods according to a difficult airway algorithm.

Background : Induction of anesthesia with propofol commonly associated with reduction in systemic arterial pressure, especially in elderly and high risk patients. This reduction is influenced by the dose and rate of propofol injection. The aim of this study was to examine the effect of different injection rate of propofol on vital signs, dose requirement and induction time during induction period. Methods : Unpremedicated one hundred and twenty ASA physical status I and II patients aged 20∼60 years scheduled for elective surgery were randomly allocated into one of four(150, 300, 600, 1200 ml/hr) groups according to speed of injection of propofol during induction period. Loss of verbal contact was taken as the end-point of induction. Vital signs, SpO2, dose requirement of propofol and induction time were checked. Results : As the injection rate of propofol became slower, there were significant reduction in induction dose and increase in induction time(P