Jong Yeop Kim

Prevention of rocuronium-induced withdrawal movement in children: a comparison of remifentanil with alfentanil.

Background:  This study was designed to compare the efficacy of remifentanil and alfentanil without the venous occlusion technique in preventing the withdrawal response associated with rocuronium injection in children.

Intubation without use of stylet for McGrath videolaryngoscopy in patients with expected normal airway: A randomized noninferiority trial

Background:During McGrath videolaryngoscope (VL) intubation, a styletted endotracheal tube maintaining an upward distal tip angle is recommended by some manufacturers. However, a styletted endotracheal tube can elicit rare but potentially serious complications. The purpose of this study was to demonstrate that a nonstyletted tube with exaggerated curvature would be noninferior to a styletted tube for orotracheal intubation using McGrath VL in patients with expected normal airway, by comparing the time to intubation and ease of intubation. Methods:One hundred forty patients, ages 19 to 70 years (American Society of Anesthesiologists physical status I–II), undergoing tracheal intubation for elective surgery were randomly allocated to the nonstylet group (n = 70) or the stylet group (n = 70). Anesthesia induction consisted of propofol, remifentanil, and rocuronium. The primary outcome was time to intubation assessed by a blind observer. Cormack and Lehane glottic grade, easy of intubation, and intubation difficulty score (IDS) were also assessed. Results:Median time to intubation [interquartile range] was not different between the nonstylet group and the stylet group (26 [24–32.5] s vs 27 [25–31] s, P = 0.937). There was no significant in median IDS between the nonstylet group and the stylet group (P = 0.695). Conclusion:This study shows that a nonstyletted endotracheal tube with exaggerated curvature has a similar performance to a styletted tube with a hockey-stick curvature during intubation using McGrath VL regarding time taken to successful intubation and easiness of intubation.

Effect of sex differences in remifentanil requirements for the insertion of a laryngeal mask airway during propofol anesthesia: A prospective randomized trial

Background:Remifentanil can improve insertion of a laryngeal mask airway (LMA) during induction with propofol. Recently, it has been suggested that there is a sex difference in opioid requirements for this procedure. The purposes of this study were to determine the effective effect-site concentration (Ce) of remifentanil for the facilitation of LMA insertion in male and female patients during propofol anesthesia without neuromuscular blockade and to evaluate whether there are sex differences in the Ce of remifentanil required for successful LMA insertion. Methods:Forty-eight patients (24 male, 24 female) with American Society of Anesthesiologists physical status 1 or 2, aged 20 to 60 years, scheduled for minor orthopedic surgery under general anesthesia were enrolled. Anesthesia was induced by target-controlled infusion (TCI) of propofol and remifentanil. The target Ce of propofol was 5 &mgr;g/mL initially and was reduced to 3.5 &mgr;g/mL after loss of consciousness. The Ce of remifentanil given to each patient was determined by the response of the previously tested patient using 0.5 ng/mL as a step size. The 1st patient was tested at a Ce of 3.0 ng/mL of remifentanil. Successful LMA insertion was defined as smooth insertion without patient movement or significant resistance to mouth opening. Results:The effective Ce of remifentanil required for successful LMA insertion on 50% of occasions (effective effect-site concentration for 50% [EC50]) as estimated by Dixon method was significantly lower in women (2.18 ± 0.35 ng/mL) than in men (2.82 ± 0.53 ng/mL) (P = 0.02). Using the isotonic regression method, the effective Ce of remifentanil required for successful LMA insertion on 95% of occasions (EC95) (95% confidence interval [CI]) was significantly lower in women (3.38 [3.0–3.48] ng/mL) than in men (3.94 [3.80–3.98] ng/mL). Conclusion:The Ce of remifentanil required to facilitate successful LMA insertion is higher during propofol induction by TCI in men than in women. When using remifentanil for LMA insertion, patient sex should be taken into account for appropriate dosing.

Changes in cerebral oxygen saturation and early postoperative cognitive function after laparoscopic gastrectomy: a comparison with conventional open surgery.

Background Laparoscopic gastrectomy requires a reverse-Trendelenburg position and prolonged pneumoperitoneum and it could cause significant changes in cerebral homeostasis and lead to cognitive dysfunction. We compared changes in regional cerebral oxygen saturation (rSO2), early postoperative cognitive function and hemodynamic variables in patients undergoing laparoscopic gastrectomy with those patients that underwent conventional open gastrectomy. Methods Sixty patients were enrolled in this study and the patients were distributed to receive either laparoscopic gastrectomy (laparoscopy group, n = 30) or open conventional gastrectomy (open group, n = 30). rSO2, end-tidal carbon dioxide tension, hemodynamic variables and arterial blood gas analysis were monitored during the operation. The enrolled patients underwent the mini-mental state examination 1 day before and 5 days after surgery for evaluation of early postoperative cognitive function. Results Compared to baseline value, rSO2 and end-tidal carbon dioxide tension increased significantly in the laparoscopy group after pneumoperitoneum, whereas no change was observed in the open group. No patient experienced cerebral oxygen desaturation or postoperative cognitive dysfunction. Changes in mean arterial pressure over time were significantly different between the groups (P < 0.001). Conclusions Both laparoscopic and open gastrectomy did not induce cerebral desaturation or early postoperative cognitive dysfunction in patients under desflurane anesthesia. However, rSO2 values during surgery favoured laparoscopic surgery, which was possibly related to increased cerebral blood flow due to increased carbon dioxide tension and the effect of a reverse Trendelenburg position.

Predicted EC50 and EC95 of Remifentanil for Smooth Removal of a Laryngeal Mask Airway Under Propofol Anesthesia

Purpose The purpose of this study was to determine the effect-site concentration (Ce) of remifentanil in 50% of patients (EC50) and 95% of patients (EC95) for smooth laryngeal mask airway (LMA) removal in adults under propofol and remifentanil anesthesia. Materials and Methods Twenty-five patients of ASA physical status I-II and ages 18-60 years who were to undergo minor gynecological or orthopedic surgery were assessed in this study. Anesthesia was induced and maintained with propofol and remifentanil target-controlled infusion (TCI). Remifentanil was maintained at a predetermined Ce during the emergence period. The modified Dixons up-and-down method was used to determine the remifentanil concentration, starting from 1.0 ng/mL (step size of 0.2 ng/mL). Successful removal of the LMA was regarded as absence of coughing/gagging, clenched teeth, gross purposeful movements, breath holding, laryngospasm, or desaturation to SpO2<90%. Results The mean±SD Ce of remifentanil for smooth LMA removal after propofol anesthesia was 0.83±0.16 ng/mL. Using isotonic regression with a bootstrapping approach, the estimated EC50 and EC95 of remifentanil Ce were 0.91 ng/mL [95% confidence interval (CI), 0.77-1.07 ng/mL] and 1.35 ng/mL (95% CI, 1.16-1.38 ng/mL), respectively. Conclusion Our results showed that remifentanil TCI at an established Ce is a reliable technique for achieving safe and smooth emergence without coughing, laryngospasm, or other airway reflexes.

Acute pulmonary edema after local infiltration of epinephrine during mastoidectomy - A case report -

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.

Comparison of the Pentax AirwayScope and McGrath MAC videolaryngoscope for endotracheal intubation in patients with a normal airway

Abstract Various videolaryngoscopes (VLs) have been developed to provide a better laryngeal view and facilitate difficult intubations. The goal of this study was to compare 2 VLs, the Pentax AWS and the McGrath VL, with respect to intubation time and ease of intubation. One hundred forty patients aged 19 to 65 years (American Society of Anesthesiologists classification I or II), who required tracheal intubation for elective surgery, were randomly assigned to 1 of the 2 groups: the Pentax AWS (n = 70) or the McGrath VL (n = 70). The primary outcome was time to intubation (TTI) measured by a blind observer. The intubation difficulty scale (IDS), percentage of glottic opening (POGO) scale, glottic grade, use of optimal external laryngeal manipulation (OELM), and ease of intubation were also recorded. The Pentax AWS provided a better laryngeal view than the McGrath VL with respect to the Cormack-Lehane (CL) glottic grade (1/2a/2b) (63/7/0 vs 43/24/3, P < .001) and the POGO scale (median [interquartile range, IQR]) (100 [100–100] vs 100 [80–100], P < .001). The IDS was significantly lower in the Pentax AWS group compared with the McGrath VL group (median [IQR]) (0 [0–0] vs 0 [0–1], P < .001). However, the TTI was similar in both the Pentax AWS and McGrath VL groups (median [IQR]) (30 [27–34] vs 32 [27–35] seconds, P = .440). OELM and ease of intubation were also similar between the 2 groups. The Pentax AWS offered a superior laryngeal view compared with the McGrath VL. There was no significant difference in either the intubation time or ease of intubation using these 2 devices in patients with normal airways.

Suxamethonium induces a prompt increase in the bispectral index

Abstract Upon inducting general anesthesia in the operating room, we have observed a prompt increase in the bispectral index (BIS) after the intravenous injection of suxamethonium. We hypothesized that the cause of this BIS increase is muscle hyperactivity owing to fasciculation. However, no reports have been published regarding this abrupt increase in the BIS upon the induction of general anesthesia by suxamethonium. To investigate the degree of change in the BIS in patients receiving anesthesia with suxamethonium, we performed a prospective observational study of 63 participants who underwent closed reduction for nasal bone fracture. Anesthesia was induced by the total intravenous administration of anesthetics and 1.5 mg kg−1 of suxamethonium was injected intravenously upon achieving BIS between 45 and 55. Intubation was performed after fasciculation. Electromyograms and BIS values were recorded from the induction of suxamethonium until 15 minutes after intubation. The mean BIS values were 95.4, 48.5, and 69.3 before induction, before the intravenous injection of suxamethonium, and immediately after fasciculation, respectively. The BIS value immediately after fasciculation (69.3 ± 10.6) was significantly higher than the cutoff BIS value of 60 (P < .001). Although fasciculation after the intravenous injection of suxamethonium resulted in the prompt increase of the BIS to values over 60, none of the participants was awake during surgery. In conclusion, the administration of suxamethonium resulted in the postfasciculation increase of the BIS to an average value of 69.3 without affecting the patients state of consciousness.

In reply: Assessing interaction between dexmedetomidine and propofol

1. Yoo JY, Kwak HJ, Kim YB, Park CK, Lee SY, Kim JY. The effect of dexmedetomidine pretreatment on the median effective bolus dose of propofol for facilitating laryngeal mask airway insertion. J Anesth. 2016; doi:10.1007/s00540-016-2245-7. 2. Kaur M, Singh PM. Current role of dexmedetomidine in clinical anesthesia and intensive care. Anesth Essays Res. 2011;5:128–33. 3. Chandra A, Ranjan R, Kumar J, Vohra A, Thakur VK. The effects of intravenous dexmedetomidine premedication on intraocular pressure and pressor response to laryngoscopy and intubation. J Anaesthesiol Clin Pharmacol. 2016;32:198–202. 4. Shin HW, Yoo HN, Kim DH, Lee H, Shin HJ, Lee HW. Preanesthetic dexmedetomidine 1 μg/kg single infusion is a simple, easy, and economic adjuvant for general anesthesia. Korean J Anesthesiol. 2013;65:114–20.

Optimal effect-site concentration of remifentanil for preventing cough during removal of the double-lumen endotracheal tube from sevoflurane-remifentanil anesthesia: A prospective clinical trial.

AbstractOpioids are used as a treatment for coughing. Recent studies have reported an antitussive effect of remifentanil during recovery from general anesthesia by suppressed coughing. The coughing reflex may differ throughout the respiratory tract from the larynx to the bronchi. But the proper dose of remifentanil to prevent cough during double-lumen tube (DLT) extubation is unknown.Twenty-five ASA physical status 1 and 2 patients, 20 to 65 years of age who were undergoing video-assisted thoracoscopic lung surgery requiring 1-lung ventilation were enrolled. The effective effect-site concentration (Ce) of remifentanil for 50% and 95% of patients (EC50 and EC95) for preventing cough was determined using the isotonic regression method with a bootstrapping approach, following the Dixon up-and-down method. Recovery profiles and hemodynamic values after anesthesia were compared between patients with cough and patients without cough.EC50 and EC95 of remifentanil was 1.670 ng/mL [95% confidence interval (95% CI) 1.393–1.806] and 2.275 ng/mL (95% CI 1.950–2.263), respectively. There were no differences in recovery profiles and hemodynamic values after anesthesia between patients with/without cough. No patients suffered respiratory complications during the emergence period.Remifentanil can be a safe and reliable method of cough prevention during emergence from sevoflurane anesthesia after thoracic surgery requiring DLT. EC50 and EC95 of remifentanil that suppresses coughing is 1.670 and 2.275 ng/mL, respectively.