Nan Suk Kim

Comparison of Surgical Pleth Index-guided Analgesia with Conventional Analgesia Practices in Children: A Randomized Controlled Trial.

Background:To compare surgical pleth index (SPI)-guided analgesia with conventional analgesia by evaluating intraoperative analgesic requirements, postoperative pain, and emergence agitation in children. Methods:This study was designed as a parallel, two-arm, double-blind, randomized controlled trial. Forty-five children undergoing elective adenotonsillectomy were randomly allocated to SPI-guided group (SPI-guided analgesia group, n = 21) or control group (conventional analgesia group, n = 24). Anesthesia was maintained with sevoflurane 2 to 3 vol% in 50% nitrous oxide and oxygen to achieve state entropy between 40 and 60. Intraoperative fentanyl 0.5 &mgr;g/kg was administered for the first event persisting 3 min and subsequent events persisting 5 min. An event was defined as an SPI over 50 (SPI-guided group) or a blood pressure or heart rate 20% above the baseline (control group). The primary outcome was intraoperative fentanyl requirement. Secondary outcomes included intraoperative sevoflurane consumption, postoperative emergence agitation and pain score, and postoperative rescue analgesic requirements. Results:Intraoperative fentanyl requirement was lower in SPI-guided group than in control group (0.43 ± 0.53 vs. 1.73 ± 0.59 &mgr;g/kg; P < 0.001). Intraoperative sevoflurane consumption was similar. The proportion of patients with high emergence agitation scores (4 to 5) was greater in SPI-guided group (61.9 vs. 25.0%; P = 0.01). The postoperative pain score and rescue fentanyl consumption were higher in SPI-guided group (7 [4.5; 9] vs. 3 [2; 6.75]; P = 0.002; 0.50 ± 0.34 vs. 0.29 ± 0.30 &mgr;g/kg; P = 0.04). Conclusions:As currently constructed, SPI does not appear to be valid in children. This may be due to both differences in blood vessel distensibility and baseline increased heart rates in children versus adults.

Antihistamine pretreatment to reduce incidence of withdrawal movement after rocuronium injection.

The purpose of this study was to determine the effectiveness of antihistamine therapy for withdrawal movements caused by rocuronium injection. One hundred seventy one ASA I-II adults undergoing elective surgery were randomly assigned to one of two groups. Patients in the control group (Group C) were premedicated with 2 mL normal saline, and those in the antihistamine group (Group A) were pre-medicated with 2 mL (45.5 mg) pheniramine maleate. After the administration of thiopental sodium 5 mg/kg, rocuronium 0.6 mg/kg was injected. Withdrawal movements were assessed using a four-grade scale. The administration of antihistamine reveals lower grade of withdrawal movement after rocuronium injection.

Reducing the Pain of Microemulsion Propofol Injections: A Double-Blind, Randomized Study of Three Methods of Tourniquet and Lidocaine

BACKGROUND Although the new formulation of lipid-free microemulsion propofol (MP) has some advantages over the lipid emulsion, it reportedly produces more injection pain than lipid-based propofol. Intravenous lidocaine with application of a rubber tourniquet before administration of propofol is considered to be the best method for reducing injection pain; however, this technique is not perfect. OBJECTIVE The goal of this study was to evaluate the effect of different methods of tourniquet application and lidocaine administration on MP injection pain. METHODS This single-center, randomized controlled clinical trial was conducted in 140 patients aged 18 to 65 years. Patients were randomly divided into 4 groups (n = 35 each). Group A received MP (2 mg/kg) after lidocaine (0.6 mg/kg) with a tourniquet with arm down (venous engorgement); group B received MP after lidocaine with a tourniquet with arm up (venous gravity drainage); group C received MP with a tourniquet with arm down; and group D (control group) received MP only (with no tourniquet). In groups A and C, the tourniquet was released after MP; in group B, the tourniquet was released before MP. Injection pain was evaluated by using a verbal pain score (VPS). The bispectral index, the time from the beginning of drug injection to the loss of eyelash reflex, and time to the lowest bispectral index value were recorded. RESULTS Group A showed significantly less incidence of pain than the control group when MP was injected. The mean VPS was significantly lower in groups A, B, and C than in group D (the control group). The VPS of group A was significantly lower than that in group B. Other observed values were not significantly different. CONCLUSIONS We concluded that intravenous retention of lidocaine with the application of a rubber tourniquet under venous engorgement of the arm reduces the incidence and intensity of MP injection pain. CLINICAL TRIAL REGISTRY UMIN000010725.

Comparison of emergence agitation between sevoflurane/nitrous oxide administration and sevoflurane administration alone in children undergoing adenotonsillectomy with preemptive ketorolac

Background Sevoflurane anesthesia commonly causes emergence agitation (EA) in children. One previous study has reported that the use of nitrous oxide (N2O) during the washout of sevoflurane may reduce EA by decreasing the residual sevoflurane concentration, while many animal studies suggest that N2O poses a potential risk to children. The present study was designed to compare EA in children assigned to receive sevoflurane with N2O (group N) or sevoflurane alone (group S). Methods We enrolled 80 children aged 3-10 years. Anesthesia was induced with 5 mg/kg thiopental sodium, 0.6 mg/kg rocuronium and 0.5 mg/kg ketorolac, and was maintained with 50% N2O and sevoflurane in group N or with sevoflurane alone in group S. The sevoflurane concentration was adjusted with a bispectral index (BIS) of 40-60. After completion of the surgery, N2O and sevoflurane were simultaneously discontinued and replaced with oxygen (O2) at 6 L/min. End-tidal sevoflurane concentration (Et Sevo) (%), BIS at the end of surgery, Et Sevo at recovery of self-respiration and emergence profiles were recorded. EA occurrence, pain score and rescue fentanyl consumption were assessed in the postanesthesia care unit. Results Et Sevo was significantly lower in group N (1.9%) than in group S (2.3%) at the end of surgery. However, there were no differences in Et Sevo at recovery of self-respiration, emergence times, the incidence of EA, pain score or dose of rescue fentanyl between the groups. Conclusions In children undergoing adenotonsillectomy with preemptive ketorolac, anesthetic maintenance using sevoflurane alone does not affect the incidence of EA or emergence profiles compared to anesthetic maintenance using sevoflurane with N2O.

SLIPA™ may be more useful than other LMADs for difficult airway management

To the Editor, The SLIPA, a cuffless, hollow, boot-shaped, soft plastic supraglottic airway device (SLIPA; SLIPA Medical Ltd., London, UK), has advantages over other laryngeal mask airway devices (LMADs) because it provides better protection from regurgitation and has a better perilaryngeal seal. However, SLIPA has not been tested in difficult airways. We report successful management of a difficult airway with SLIPA after laryngeal mask airway failure. We obtained the patient’s written consent to publish this report. A 50-yr-old man (169 cm, 90 kg) with gastroesophageal reflux disease (GERD) was scheduled for reconstruction of finger tendons under general anesthesia. Difficult intubation was anticipated because of the patient’s large tongue, short neck, thyromental distance, and a Mallampati score of 4. Because he refused awake fibreoptic intubation, we decided to insert a LMAD. After administering fentanyl 100 lg, thiopental sodium 450 mg, and succinylcholine 90 mg, a LMAD (Solus; Intersurgical Ltd. Wokingham, UK) size 5 was inserted. Immediately after insertion, no leak was heard, the end-tidal carbon dioxide concentration (ETCO2) was 28-30 mmHg, and the peak inspiratory airway pressure (PIP) was 22-25 cm H2O. At one minute after insertion, however, the PIP suddenly increased to 35 cmH2O, and a leak was detected. The LMAD was removed, and another insertion attempt was made after administering succinylcholine 50 mg. This time, the PIP was 40-45 cm H2O, and leaks were audible immediately. A fibreoptic bronchoscope (FOB) was inserted through the airway port of the LMAD, and the anterior portion of the epiglottis was found to be blocking the view. The fibrescope was passed under the epiglottis to examine the glottis, and a glottic narrowing was found. After removing the LMAD, a size 55 SLIPA was inserted. The PIP decreased to 20-23 cm H2O, and the ETCO2 was 32-33 mmHg. No leak was detected. The FOB was inserted, through which the vocal cords were well visualized, and the periglottic seal was seen to be improved. Afterward, ventilation was maintained well, and there were no complications, including airway obstruction or aspiration. Examination of the glottis via the FOB provided possible explanations for the different performances of the two devices. First, the position of the epiglottis was different, which might be due to the designs of the respective bowls. The laryngeal aperture of SLIPA consists of a wide portion and a narrow portion, preventing airway obstruction (Figure), whereas the absence of epiglottic bars on the Solus could cause epiglottis downfolding and subsequent airway obstruction. However, previous reports suggested that because disposable LMADs, including the Solus, have a deeper bowl, ventilation is well maintained despite the absence of epiglottic bars. In this case, the FOB passed under the epiglottis with ease, which makes obstruction by the epiglottis improbable. Second, the presence of a cuff and the shape and location of the bowl should be considered. The space between the tongue and posterior pharyngeal wall was probably narrow in this patient, becoming narrower because of laryngopharyngeal edema caused by GERD. In a narrow space, inflating the LMAD cuff could increase pressure in the laryngopharynx and cause distortion of laryngeal B. G. Lim, MD K. J. Kim, MD M. H. Kong, MD, PhD N. S. Kim, MD, PhD S. H. Lim, MD, PhD M. K. Lee, MD, PhD I. O. Lee, MD, PhD (&) Guro Hospital, College of Medicine, Korea University, Seoul, South Korea e-mail: iloklee@korea.ac.kr

Comparison of bispectral index (BIS) and entropy in patients with cerebral palsy during sevoflurane induction

BACKGROUND Demand of anesthesia for patients with cerebral palsy is more increasing. But there is still lacking in clinical research regarding how BIS and entropy reflect well on sedative and hypnotic state in patients with cerebral palsy. METHODS Fifteen patients with cerebral palsy (Group CP) and fifteen patients without cerebral palsy (Group NL) scheduled for elective orthopedic surgery were included in the study. Induction of anesthesia was done by having the patient inhale 1 vol% sevoflurane and 100% oxygen using a total fresh gas flow of 8 L/min. Simultaneously BIS, state entropy (SE), response entropy (RE), end-tidal sevoflurane concentration were recorded every 15 seconds till there was no self respiration. When end-tidal sevoflurane concentration had not risen any more for 30 seconds, we increased inhaled sevoflurane concentration in 1 vol% increments. End point of recording was when self respiration was lost or the time sevoflurane concentration reached 8 vol%. RESULTS No significant differences in RE, SE, BIS at baseline and end point were found between the two groups. No significant difference in the time reach end point was found between the two groups. BIS, SE and RE correlated with end-tidal sevoflurane concentration in the two groups. CONCLUSIONS The authors found no significant difference in the entropy values between patients with CP and normal patients. Also, the entropy values could be interpreted like BIS in patients with CP. And BIS showed a stronger correlation with end tidal sevoflurane concentrations than entropy.

The effects of hydrogen sulfide under sevoflurane administration against ischemia and reperfusion injury in isolated rat heart

Background Hydrogen sulfide (H2S) produces a protective effect against myocardial ischemia and reperfusion injury. Sevoflurane, which is used for anesthesia in cardiac problem patients, also has a protective effect. This study is designed to reveal the effects of H2S under sevoflurane using rat hearts. Methods The hearts were Langendorff-perfused, subjected to 30 minutes ischemia and 60 minutes reperfusion. Group I was a control group. The other groups were pretreated for 15 minutes before ischemia as follows: 1.6% sevoflurane for group S; 18.5 µM H2S S for group H; and 1.6% sevoflurane and 18.5 µM H2S simultaneously for group HS. Hemodynamics and the infarct size were measured. Results Group HS presented depressed hemodynamics during pretreatment. LV function in group HS achieved better recovery than group I after reperfusion. The infarct size of groups S, H and HS was smaller than group I, while there were no differences between groups S, H and HS. Conclusions Exogenous H2S did not enhance the preconditioning effects of sevoflurane. Rather, the results suggest that H2S under sevoflurane might depress hemodynamics.