Influence of electrocautery-induced electromagnetic interference on quantitative electroencephalographic monitoring of hypnosis during general anesthesia: comparison between the ADMS® and the BIS VISTATM / 대한마취과학회지

BACKGROUND: Hypnosis monitors analyze small-amplitude electrical signals transmitted from the brain that could be exposed to the electromagnetic field that occurs around the body during electrocautery (ECT). We investigated the influence of ECT on hypnosis monitoring during anesthesia. METHODS: We simultaneously monitored BIS and uCON during 50 gynecologic oncology surgeries. During the episodes of ECT, we compared the absolute difference (a-Diff) between the baseline index and the most deviated index after ECT over either 30–60 s (ECT30–60) or more than 60 s (ECT > 60) between the monitors. We also investigated the bias and the limits of agreement between the monitors. RESULTS: Between the two monitors, the a-Diff of ECT30–60 was 1.4 ± 1.1 for the BIS, which was significantly greater than 0.6 ± 0.9 for the uCON (P = 0.003), and the a-Diff of ECT > 60 was 16.5 ± 8.2 for the BIS, which was also significantly greater than 1.4 ± 1.3 for uCON (P 60 was significantly greater than that during ECT30–60 (P 60 (P = 0.056). The estimated bias between the monitors was 6.3 ± 9.8 and 95% limits agreement was –12.3 to 25.0. CONCLUSIONS: Prolonged ECT intervention might lead to spurious estimations of quantitative EEG indexes. Therefore, hypnosis should be clinically assessed in combination with scrutinized judgment of relevant clinical symptoms and signs for hypnosis.

Correction of target-controlled infusion following wrong selection of emulsion concentrations of propofol / 대한마취과학회지

BACKGROUND: We investigated the correction methods following wrong-settings of emulsion concentrations of propofol as a countermeasure against erroneous target-controlled infusions (TCI). METHODS: TCIs were started with targeting 4.0 microg/ml of effect-site concentration (C(eff)) of propofol, and the emulsion concentrations were selected for 2.0% instead of 1.0% (FALSE(1-2), n = 24), or 1.0% instead of 2.0% (FALSE(2-1), n = 24). These wrong TCIs were corrected at 3 min after infusion start. During FALSE(1-2), the deficit was filled up while injecting after equilibrium (n = 12), or while overriding (n = 12). During FALSE(2-1), the overdose was evacuated while targeting C(eff) (n = 12) or targeting plasma concentration (C(p)) (n = 12). The gravimetrical measurements of TCI reproduced the C(p) and C(eff) using simulations. The reproduced C(eff) at 3 min (C(eff-3min)) and the time to be normalized within +/- 5% of target C(eff) (T(+/-5%)), were compared between the correction methods. RESULTS: During the wrong TCI, C(eff-3min) was 1.98 +/- 0.01 microg/ml in FALSE(1-2), and 7.99 +/- 0.05 microg/ml in FALSE(2-1). In FALSE(1-2), T(+/-5%) was significantly shorter when corrected while overriding (3.9 +/- 0.25 min), than corrected after equilibrium (6.9 +/- 0.05 min) (P < 0.001). In FALSE(2-1), T(+/-5%) was significantly shorter during targeting C(p) (3.6 +/- 0.04 min) than targeting C(eff) (6.7 +/- 0.15 min) (P < 0.001). CONCLUSIONS: The correction methods, based on the pharmacokinetic and pharmacodynamic characteristics, could effectively and rapidly normalize the wrong TCI following erroneously selections of the emulsion concentration of propofol.

Arrangements of the intravenous parallel infusions with anti-reflux valves decreasing occlusion alarm delay / 대한마취과학회지

BACKGROUND: The methods of arrangement of combined intravenous parallel infusions using anti-reflux valve (ARV), with and without anti-syphon valve (ASV) that could decrease occlusion alarm delay were investigated. METHODS: Occlusion challenge tests were mainly performed as bench experiments of four kinds of multiple parallel infusions (10 ml/h and 50 ml/h infusions), which were connected at the proximal or distal portion of ARV, with or without ASV. Alarm threshold was set to 1000 mmHg. Occlusion alarm delays and the compliances of the infusion systems were compared among groups. RESULTS: Without ASV, compared to 10 ml/h infusion alone distal to anti-reflux valve, 50 ml/h infusion distal to anti-reflux valve reduced the mean alarm delay from 416 +/- 7 s to 81 +/- 3 s (P < 0.001). Compared to 50 ml/h infusion alone, combined 10 ml/h and 50 ml/h infusion distal to ARV prolonged the alarm delay from 81 +/- 3 s to 133 +/- 6 s (P < 0.001). However, combined infusions distal to ARV with ASV significantly reduced the alarm delay from 133 +/- 6 s to 74 +/- 5 s (P < 0.001), and also reduced the compliance of the infusion system from 2.31 +/- 0.12 to 1.20 +/- 0.08 microl/mmHg (P < 0.001). CONCLUSIONS: The infusion setup of faster infusion rate, lower compliant system using ASV could effectively decrease occlusion alarm delay during multiple intravenous parallel infusions using ARV.

The efficacy of the time-scheduled decremental continuous infusion of fentanyl for postoperative patient-controlled analgesia after total intravenous anesthesia / 대한마취과학회지

BACKGROUND: Intravenous fentanyl has been used for acute postoperative pain management, but has not always provided reliable adequate analgesia, including patient-controlled analgesia (PCA). The purpose of this study was to investigate the efficacy of time-scheduled decremental infusion of fentanyl for postoperative analgesia. METHODS: Ninety-nine patients, aged 20-65 years, undergoing laparoscopic-assisted hysterectomy using total intravenous anesthesia (TIVA) were randomly assigned into one of the three groups. Their background infusions of fentanyl diluent (2 ml/hr of diluent was equivalent with 0.5 microg/kg/hr of fentanyl) with PCA were maintained at the fixed-rate of 2 ml/hr until the postoperative 24 hr (FX2-2-2), or at the decremental rates of 6.0, 4.0, 2.0 ml/hr (D6-4-2) and 8.0, 4.0, 2.0 ml/hr (D8-4-2). The visual analogue score (VAS), incidence of inadequate analgesia, frequency of PCA intervention, and side effects were evaluated. RESULTS: VAS was significantly higher in FX2-2-2 than in D6-4-2 and D8-4-2 until postoperative 3 hr (P < 0.05). After postoperative 4 hr, VAS was significantly higher in FX2-2-2 than D8-4-2 (P < 0.05). The incidence of inadequate analgesia of FX2-2-2 was significantly greater than D6-4-2 (P = 0.038) and D8-4-2 (P < 0.001) until postoperative 1 hr. None of the patients had ventilatory depression, and postoperative nausea and vomiting were not significant among the groups. CONCLUSIONS: The time-scheduled decremental background infusion regimens of fentanyl, based on the pharmacokinetic model, could provide more effective postoperative pain management after TIVA, and the side effects and the risk for morbidity were not different from the fixed-rate infusion regimen.

Impact of priming the infusion system on the performance of target-controlled infusion of remifentanil / 대한마취과학회지

BACKGROUND: The start-up behavior of syringe and syringe pump is known to be one of the causes of inaccurate intravenous infusion. This study evaluated the method of priming the infusion system (PRIMING), and its impact on the target-controlled infusion (TCI) of two remifentanil diluents. METHODS: PRIMING was performed using an evacuation of 2.0 ml to the atmosphere prior to TCI. Forty-eight TCI, using 50 microg/ml (Remi50) or 20 microg/ml (Remi20) of diluents, were performed targeting 4.0 ng/ml of effect-site concentration (Ceff), with PRIMING or not. The gravimetrical measurements of the delivered infusates reproduced actual Ceff. The bolus amount and time to reach 95% target were compared. RESULTS: Without PRIMING, Remi50 infused less bolus (43 +/- 23 %) than Remi20 (19 +/- 9 %) (P = 0.003), and showed more delayed increase of Ceff (11.2 +/- 4.0 min) than Remi20 (7.4 +/- 0.4 min) (P = 0.028). However, PRIMING significantly decreased the deficit of the bolus (2 +/- 1%), as well as the delay of the increase of Ceff in Remi50 (1.2 +/- 0.2 min) (both P < 0.001). In addition, with PRIMING, the start-up bolus showed minimal difference to the nominal bolus (1 and 2%), and Ceff were increased to 4.0 +/- 0.1 ng/ml at the expected time of peak effect, irrespective of the diluents. CONCLUSIONS: Proper operation of the syringe pump used in the priming of the syringe may be helpful in reduction of the inaccuracy of TCI, particularly during the early phase of infusion, or the infusion of a more concentrated diluent.

False selection of syringe-brand compatibility and the method of correction during target-controlled infusion of propofol / 대한마취과학회지

BACKGROUND: We evaluated volumetric differences of syringe brand compatibilities, and investigated the impact of false brand settings on target-controlled infusion (TCI) and their methods of correction. METHODS: Gravimetric measurement of 10 ml bolus infusions was performed using BD Plastipak (BDP) and Terumo compatible syringes, while setting to 7 different kinds of brand compatibilities (BDP, Sherwood Monoject, BD Perfusion, Braun Perfusor, Braun Omnifix, Fresenius Injectomat, and Terumo). To investigate the performance of TCI using BDP with a false setting to Terumo (BDPTERUMO) and Terumo to BDP (TERUMOBDP), 24 TCI targeting 4.0 microg/ml of effect-site concentration (Ceff) of propofol were performed. Subsequently, another 24 TCI were evaluated for simple corrections of false settings at 30 min. We also investigated 24 TCI using active corrections (fill-up for BDPTERUMO, evacuation for TERUMOBDP) based on the pharmacokinetics of propofol. The Ceff at 30 min of TCI and time to normalize to +/- 5% of target concentration (T+/-5%target) were compared. RESULTS: The Ceff of BDPTERUMO showed negative bias and 17.2% inaccuracy, and the Ceff of TERUMOBDP showed positive bias and 19.5% inaccuracy. The Ceff at 30 min showed no difference between the methods of correction in BDPTERUMO or TERUMOBDP. The T+/-5%target in both the active corrections was significantly shorter than that of each simple corrections (P < 0.001). CONCLUSIONS: False brand setting of syringe proportionally maintained different predicted concentrations as much as the volumetric differences of syringe brand. Based on the results, it is proposed that correction methods based on pharmacokinetics could effectively normalize the differences, without giving up the wrong TCI.

Occurrence and characterization of oseltamivir-resistant influenza virus in children between 2007-2008 and 2008-2009 seasons / 소아과

PURPOSE: There was a global increase in the prevalence of oseltamivir-resistant influenza viruses during the 2007-2008 influenza season. This study was conducted to investigate the occurrence and characteristics of oseltamivir-resistant influenza viruses during the 2007-2008 and 2008-2009 influenza seasons among patients who were treated with oseltamivir (group A) and those that did not receive oseltamivir (group B). METHODS: A prospective study was conducted on 321 pediatric patients who were hospitalized because of influenza during the 2007-2008 and 2008-2009 influenza seasons. Drug resistance tests were conducted on influenza viruses isolated from 91 patients. RESULTS: There was no significant difference between the clinical characteristics of groups A and B during both seasons. Influenza A/H1N1, isolated from both groups A and B during the 2007-2008 and 2008-2009 periods, was not resistant to zanamivir. However, phenotypic analysis of the virus revealed a high oseltamivir IC50 range and that H275Y substitution of the neuraminidase (NA) gene and partial variation of the hemagglutinin (HA) gene did not affect its antigenicity to the HA vaccine even though group A had a shorter hospitalization duration and fewer lower respiratory tract complications than group B. In addition, there was no significant difference in the clinical manifestations between oseltamivir-susceptible and oseltamivir-resistant strains of influenza A/H1N1. CONCLUSION: Establishment of guidelines to efficiently treat influenza with oseltamivir, a commonly used drug for treating influenza in Korean pediatric patients, and a treatment strategy with a new therapeutic agent is required.

Cross-simulation between two pharmacokinetic models for the target-controlled infusion of propofol / 대한마취과학회지

BACKGROUND: We investigated how one pharmacokinetic (PK) model differed in prediction of plasma (Cp) and effect-site concentration (Ceff) using a reproducing simulation of target-controlled infusion (TCI) with another PK model of propofol. METHODS: Sixty female patients were randomly assigned to TCI using Marsh PK (Group M) and TCI using Schnider PK (Group S) targeting 6.0 microg/ml of Cp of propofol for induction of anesthesia, and loss of responsiveness (LOR) was evaluated. Total and separate cross-simulation were investigated using the 2 hr TCI data (Marsh TCI and Schnider TCI), and we investigated the reproduced predicted concentrations (MARSHSCH and SCHNIDERMAR) using the other model. The correlation of the difference with covariates, and the influence of the PK parameters on the difference of prediction were investigated. RESULTS: Group M had a shorter time to LOR compared to Group S (P < 0.001), but Ceff at LOR was not different between groups. Reproduced simulations showed different time courses of Cp. MARSHSCH predicted a higher concentration during the early phase, whereas SCHNIDERMAR was maintained at a higher concentration. Volume and clearance of the central compartment were relevant to the difference of prediction, respectively. Body weight correlated well with differences in prediction between models (Rsqr = 0.9821, P < 0.001). CONCLUSIONS: We compared two PK models to determine the different infusion behaviors during TCI, which resulted from the different parameter sets for each PK model.

A target-controlled infusion regimen for reducing remifentanil-induced coughs / 대한마취과학회지

BACKGROUND: This study evaluates the effectiveness of the target-controlled infusion (TCI) of remifentanil through stepwise increases in the effect-site concentration (Ceff) in preventing coughs. METHODS: In a preliminary study, we randomly selected 140 patients to receive remifentanil through two-step increases in Ceff (1.0 ng/ml to 4.0 ng/ml: Group R1-4; 2.0 ng/ml to 4.0 ng/ml: Group R2-4). Based on the results of the preliminary study, we employed another sample of 140 patients and implemented a three-step increase in TCI (1.0 ng/ml to 2.0 ng/ml to 4.0 ng/ml: Group R1-2-4). We then compared this treatment with direct targeting based on 4.0 ng/ml TCI (Group R4). We recorded the episodes of coughs, rating them as mild (1-2), moderate (3-4), or severe (5 or more). RESULTS: In Group R1-4, one patient (1.5%) coughed during the first step, and five (7.3%) coughed during the second step. In Group R2-4, nine (13.2%) coughed during the first step, but none coughed during the next step. Only one patient had a mild cough during the three-step increase in TCI, that is, patients in Group R1-2-4 were significantly less likely to cough than those in Group R4 (P < 0.001). CONCLUSIONS: Stepwise increases in the TCI of remifentanil reduced the incidence of remifentanil-induced coughing, and the three-step increase in TCI nearly eliminated remifentanil-induced coughing.

Comparison of the effects of sevoflurane and propofol on core body temperature during laparoscopic abdominal surgery / 대한마취과학회지

BACKGROUND: A decrease in core body temperature caused by heat distribution depends on the anesthetic agent used. The purpose of this study is to investigate the effects of sevoflurane and propofol on core temperature during laparoscopic major abdominal surgery requiring pneumoperitoneum of more than 90 min. METHODS: Fifty adult patients undergoing laparoscopic major abdominal surgery were randomly assigned to either a sevoflurane group (n = 25) or a propofol group (n = 25). In the sevoflurane group, anesthesia was induced with propofol 2 mg/kg, remifentanil 1.0 microg/kg, and maintained with 0.8-2.0 vol% sevoflurane and 0.1-0.2 microg/kg/min remifentanil. In the propofol group, anesthesia was induced with the effect-site concentration of propofol of 5.0 microg/ml and remifentanil 4 ng/ml, and maintained with the effect-site concentration of propofol of 2-3.5 microg/ml and remifentanil 3-5 ng/ml. Core body temperature was measured with an esophageal stethoscope with a temperature sensor after the start of the pneumoperitoneum (baseline) and at 15-min intervals until completion of surgery. RESULTS: During the study period, core temperature was comparable between the two groups. When compared with baseline values, core temperatures in both groups were significantly decreased 45 min after pneumoperitoneum. CONCLUSIONS: This study demonstrated that in patients undergoing prolonged laparoscopic surgery, a decrease in core body temperature during sevoflurane-remifentanil anesthesia was not different than propofol-remifentanil anesthesia, and the incidence of hypothermia of the two groups did not differ.

Comparison of effect-site concentration of remifentanil for tracheal intubation with the lightwand and laryngoscopy during propofol target-controlled infusion / 대한마취과학회지

BACKGROUND: Target-controlled infusion (TCI) of propofol and remifentanil can provide satisfactory intubating conditions without a neuromuscular blocking agent. We compared the effect-site concentration of remifentanil required for intubation with the lightwand and the Macintosh laryngoscope during propofol TCI without a neuromuscular blocking agent in adult patients. METHODS: Forty-nine patients were randomly assigned to the lightwand group (n = 25) or the direct laryngoscope group (n = 24). Anesthesia was induced by propofol TCI with an effect-site concentration of 5.4 microg/ml. Two minutes after start of propofol TCI, remifentanil was administered at the predetermined effect-site concentration. The effect-site concentration of remifentanil was determined using Dixon's up-and-down method (0.5 ng/ml as a step size). The first patient in each group was tested at 4.5 ng/ml of remifentanil. Tracheal intubation was performed 2 min after the start of remifentanil TCI. Acceptable intubation was defined as an excellent or good intubating conditions. RESULTS: Using a modified Dixon's up and down method, the EC50 +/- SD of remifentanil in the lightwand and laryngoscope groups was 4.75 +/- 0.71 ng/ml and 5.08 +/- 0.52 ng/ml, respectively; there was no statistically significant difference between the groups (P = 0.373). CONCLUSIONS: The effect-site concentration of remifentanil for acceptable intubation with the lightwand and Macintosh laryngoscope in 50% of adults did not differ during propofol TCI without a neuromuscular blocking agent.

Viral Etiology and Epidemiology of Outpatients with Acute Respiratory Illnesses in Busan: 2007-2008 / 소아감염

PURPOSE: The purpose of this study is to identify the viral etiology of acute respiratory illnesses and to determine epidemiology in outpatients in Busan, Korea. METHODS: We collected nasal wash samples from 990 patients who visited the hospital for acute respiratory illnesses between January 2007 and December 2008. Extracted DNA or RNA from specimens was used for viral detection by an RT-PCR method. RESULTS: Of a total of 990 samples, viruses were detected in 351 cases (35.5%). The ratio of male to female was 1.6:1 and 93.7% were less than 5 years old. Rhinovirus was detected year-round in 202 cases (57.5%), respiratory syncytial virus from October to March in 57 cases (16.2%), adenovirus year-round in 37 cases (10.5%), influenza virus from December to April in 21 cases (6%), bocavirus from January to August in 15 cases (4.3%), parainfluenza virus from April to July in 9 cases (2.6%), coronavirus from January to July in 7 cases (2%), and enterovirus from June to September in 3 cases (0.9%). CONCLUSION: We identified the etiology and epidemiology of viruses that caused the acute respiratory diseases that were prevalent in Busan, 2007-2008. Further surveillance will be necessary.

Titration of the plasma effect site equilibrium rate constant of propofol; a link method of 'Concentration-Probability-Time' / 대한마취과학회지

BACKGROUND: The plasma effect-site equilibrium rate constant (k(e0)) of propofol has been reported in various pharmacodynamic studies; however, it is not desirable to apply k(e0) for the link with pharmacokinetic models that were separately investigated. Thus, we titrated k(e0) for the pharmacokinetic model, which is known as the multiple covariates adjusted model of propofol. METHODS: Ninety female patients scheduled for gynecologic surgery were randomly assigned to three groups targeting different plasma concentrations of 5.4, 8.1, and 10.8 microgram/ml. Target-controlled infusions (TCI) were provided by a computer-assisted continuous infusion system. Time to loss of responsiveness (LOR) was measured by a blind investigator; effect-site concentrations (C(e)) for LOR were then calculated with simulation of TCI using different k(e0)s. We determined the k(e0) minimizing total discrepancy (TD) between the inputted and calculated k(e0) from the t(1/2)k(e0)s for a given probability of LOR of the C(e), and also obtained the k(e0) for the minimal TD between the median Ce, which were compared to the known k(e0). RESULTS: k(e0)s from these two methods were 0.3692 and 0.3788/min. C(e)s for LOR with these k(e0)s were significantly different from those with Schnider's k(e0). CONCLUSIONS: We proposed a method for titration of the k(e0) of propofol. The k(e0)s of propofol was lower than Schnider's k(e0). An adequate k(e0) for the specific pharmacokinetic model and a certain population would be useful for prediction of an accurate C(e), and could be used for calculation of accurate dosing during targeting of the effect site.

Increase of blood pressure and heart rate during desflurane inhalation in a patient with tracheostomy state: A case report

A rapid increase in desflurane concentration induces hypertension and tachycardia and increases plasma catecholamine concentration. This sympathetic stimulation occurs when desflurane is inspired with high concentration shortly after anesthetic induction or when the inspired concentration of desflurane is rapidly increased during steady-state periods of anesthesia. We represent a case of increase of blood pressure and heart rate during desflurane inhalation in a patient with tracheostomy state.

Acute pulmonary edema after local infiltration of epinephrine during mastoidectomy: A case report / 대한마취과학회지

A mixture of local anesthetic and epinephrine provides hemostasis for ear microsurgery. However, epinephrine has adverse cardiovascular effects, such as arrhythmia, pulmonary edema, and even cardiac arrest. We have experienced catecholamine-induced cardiovascular crisis, with severe hypertension, tachycardia, and acute pulmonary edema, after subcutaneous infiltration with a 2% lidocaine and 1:200,000 epinephrine solution. The patient recovered without any apparent sequelae after intensive care, including diuretics, steroids, and nitroglycerin for the hypertension and pulmonary edema, and a vasopressor for the subsequent hypotension.

Hemodynamic Changes after Endotracheal Intubation in Patients with Cerebral Aneurysm

BACKGROUND: Tracheal intubation with a lightwand intubating device (Trachlight) attenuates the hemodynamic stress response to tracheal intubation compared with a direct laryngoscope approach. We compared the effects of the direct laryngoscope (Macintosh blade) and lightwand for intubation in patients with cerebral aneurysm. METHODS: Twenty-four patients undergoing cerebral aneurysm clipping surgery were randomly divided to either the lightwand (Group 1, n = 12) or the laryngoscope (Group 2, n = 12) Group. All patients received fentanyl (2-3microg/kg), midazolam (0.1 mg/kg), and thiopental sodium (2-3microg/kg) followed by vecuronium (0.1- 0.15microg/kg). The lungs were ventilated with 3-4% isoflurane in oxygen, with 1% lidocaine (1-1.5microg/kg) administered before intubation with either the lightwand or the laryngoscope. Systolic, diastolic and mean blood pressures and heart rate were recorded continuously before and for 5 min after intubation. RESULTS: Systolic and mean arterial blood pressure increased significantly (P < 0.05) 1 minute after intubation, but then returned to normal within the next minute. There were no differences in hemodynamic changes between the two groups, and no complications. CONCLUSIONS: Intubation technique did not affect hemodynamic changes in patients with cerebral aneurysm. In patients with aneurysms, appropriate anesthetic levels and pharmacologic manipulation will attenuate the hemodynamic stress response associated with tracheal intubation.

Agreement Evaluation between Noninvasive Oscillometric Blood Pressure Measured by the Tram 800SL Module of Solar 8000M(R) with Invasive Arterial Blood Pressure Measured by the AMK 250 AutoTransducer(R) during General Anesthesia / 대한마취과학회지

BACKGROUND: Blood pressure (BP) varies considerably during general anesthesia. Accurate BP measurement is critical for appropriate treatment, especially during hypotension and hypertension. Here we evaluated whether the noninvasive oscillometric BP measurement technique accurately reflects BP measured by the direct intraarterial technique. METHODS: A total of 256 samples were extracted from 10 patients operated on under general anesthesia. Systolic, diastolic and mean BP were analyzed according to the level of BP; hypotension, normotension, and hypertension. Repeatability of the noninvasive BP measurement were analyzed with repeatability coefficients and percent errors. Agreement between the two BP measurements were analyzed with a Bland-Altman and Modified Bland-Altman analysis. RESULTS: The repeatability coefficient for mean BP of the noninvasive oscillometric BP measurement was 6.34. Percent errors of mean BP were smaller than those of systolic and diastolic BP. All biases were less than 5 mmHg at all BP levels. Most BP agreements were larger than 8 mmHg except all-range mean BP (7.7), hypotensive diastolic BP (6.7), and mean BP (6.2). During hypotension, only mean BP was within the 95% of confidence interval (CI) of bias and limit of agreement. During hypertension, only systolic BP could meet the criteria. CONCLUSIONS: Only mean BP during hypotension and systolic BP during hypertension accurately reflect the direct intraarterial BP. But, diastolic BP does not reflect the direct intraarterial BP over all BPs.

The Effect of Ondansetron or Dolasetron for the Prevention of Postoperative Nausea and Vomiting in Patients with Intravenous Patient-controlled Analgesia / 대한마취과학회지

BACKGROUND: Postoperative nausea and vomiting (PONV) are common problems in patients undergoing breast surgery or with intravenous patient-controlled analgesia (IV PCA). We evaluated the effect of ondansetron or dolasetron for the prevention of PONV in patients undergoing a mastectomy with IV PCA. METHODS: A total of 126 patients were randomly divided into three groups. The PCA group was a control group. For the PCAO group (IV PCA mixed with ondanseron), 4 mg ondansetron was intravenously injected 30 min before the end of surgery and 8 mg was mixed in IV PCA. For the PCAD group (IV PCA mixed with dolasetron), 10 mg dolasetron and 20 mg was administered as same manner with the PCAO group. The incidence of PONV, the need for rescue antiemetics, adverse events, and the nausea and vomiting severity score were analyzed for 1 hour and 24 hours postoperative periods. RESULTS: During the first 24 hours postoperatively, the incidence of PONV was 76.2% for the PCA group, 70.7% for the PCAO group (P > 0.05 versus the PCA group) and 66.7% for the PCAD group (P > 0.05 versus the PCA group), respectively. The incidence of need for rescue antiemetics was 40.5% for the PCA group, 9.5% for the PCAO group (P < 0.05 versus the PCA group) and 4.8% for the PCAD group (P < 0.05 versus the PCA group), respectively. CONCLUSIONS: In the patients receiving IV PCA after a mastectomy, ondansetron or dolasetron were not effective for the reduction of the incidence of PONV. However, the need for rescue antiemetics was significantly decreased.

Inhalation Induction of Anesthesia with 8% Sevoflurane in Pediatric Ambulatory Surgery: Conditions for Nasotracheal Intubation and the Effects of Dexamethasone on Postoperative Nausea and Vomiting / 대한마취과학회지

BACKGROUNDS: In this study, we assessed nasotracheal intubation conditions following an inhalation induction using 8% sevoflurane and nitrous oxide with fentanyl and evaluated the effect of 0.1 mg/kg dexamethasone on postoperative nausea and vomiting (PONV) in pediatric ambulatory patients. METHODS: Forty-two pediatric patients requiring nasotracheal intubation were scheduled for ambulatory procedures. Anesthesia was induced with sevoflurane 8% in a nitrous oxide and oxygen mixture, and after an end-expiratory concentration of sevoflurane of at least 4.5% had been reached, the trachea was intubated. Intubating conditions were graded as excellent, good, poor or impossible according to Good Clinical Research Practice criteria, and the incidence of adverse events during induction were also noted. Patients were randomly allocated to receive normal saline (control group, n = 20) or dexamethasone 0.1 mg/kg (dexamethasone group, n= 22) after the induction of anesthesia. RESULTS: Nasotracheal intubation was accomplished successfully in 100% of the patients and clinically acceptable intubating conditions were obtained in 38 patients (25 excellent and 13 good). There were no significant differences between the two groups in age, sex, and operation time. In the 0 to 6 hour postoperative period, the incidences of PONV were 15% and 9% in the control and dexamethasone groups respectively, but this was not significantly different. CONCLUSIONS: Induction with sevoflurane in nitrous oxide and oxygen provided ideal conditions for nasotracheal intubation. Intraoperative dexamethasone did not significantly reduce PONV after inhalation induction and maintenance with sevoflurane during the first 6 hour postoperative period in pediatric patients.

The Target Plasma Concentrations of Propofol for a Rapid Loss of Responsiveness during the Induction of Anesthesia / 대한마취과학회지

BACKGROUND: Although the target plasma concentrations of propofol required for the induction of anesthesia have been studied extensively, the relationship between the duration of induction and target plasma concentration have not yet been described fully. We studied the target plasma concentration of propofol required for a rapid loss of responsiveness (LOR) during the induction of anesthesia, and the adverse effects and the incidence of induction failure, and compared this with the bolus administration of propofol. METHODS: ASA physical status I, unpremedicated, 21-40 yr, 174 female patients scheduled for minor gynecologic surgery under general anesthesia were randomly assigned to eight different groups. In groups I and II, propofol 2.0 mg/kg or 2.3 mg/kg were administrated to induce anesthesia. In the other 6 groups, target plasma concentrations were set at 5.4, 6.1, 6.8, 7.4, 8.1 and 8.8microgram/ml. Every 5 seconds the patients were asked to open their eyes. The time to LOR was measured by a blinded investigator. The target plasma concentrations of propofol for LOR within 60, 90, 120, 180 and 300 seconds were calculated by regression and probit analysis. RESULTS: The target plasma concentrations of propofol for LOR within 60, 90, 120, 180 and 300 seconds in 95% of patients were 9.5, 8.4, 8.2, 7.4 and 6.5 microgram/ml, respectively. The incidence of hypotension and bradycardia were not different between groups, but the incidence of induction failure was significantly higher in Group I (P < 0.05). CONCLUSIONS: We evaluated the use of the target-controlled infusion of propofol for LOR within 1 to 5 minutes in this prospective, randomized study and demonstrate the target plasma concentration of propofol required for the rapid LOR in 95% of healthy, unpremedicated female patients.