Kwang-Suk Seo

Delayed emergence process does not result in a lower incidence of emergence agitation after sevoflurane anesthesia in children.

Background:  Emergence agitation (EA) is more frequent after sevoflurane anesthesia than other inhalational agents but the etiology remains unclear. We investigated whether the EA after sevoflurane anesthesia is related to rapid emergence.

A New Technique to Reduce Epistaxis and Enhance Navigability During Nasotracheal Intubation

BACKGROUND:Epistaxis is the most common complication of nasotracheal intubation. We compared endotracheal tubes (ETT) obturated with an inflated esophageal stethoscope with normal ETTs with regard to the prevention of epistaxis and navigability, both with and without thermosoftening. METHODS:Dental surgical patients requiring nasotracheal intubation were randomly allocated into 1 of 4 groups (n = 50 each): Group 1, nonthermosoftened ETTs; Group 2, nonthermosoftened ETTs obturated with an inflated esophageal stethoscope; Group 3, thermosoftened ETTs; and Group 4, thermosoftened ETTs obturated with an inflated esophageal stethoscope. Navigability of ETTs through the nasal cavity and postintubation epistaxis were evaluated. RESULTS:Navigability of ETTs through the nasal cavity was the worst in Group 1 (P = 0.001). Epistaxis was the most severe in Group 1, similar between Groups 2 and 3, and the least severe in Group 4 (P < 0.001). CONCLUSION:The use of esophageal stethoscope-obturated ETTs was effective, and comparable to thermosoftening, in preventing epistaxis associated with nasotracheal intubation. Thermosoftened, obturated ETTs were more effective than simple thermosoftened ETTs in reducing epistaxis.

Prevention of withdrawal movement associated with injection of rocuronium in children: comparison of remifentanil, alfentanil and fentanyl.

Background:  We compared the efficacy of remifentanil, alfentanil and fentanyl in reducing withdrawal movement associated with the injection of rocuronium in children.

Antinociceptive curcuminoid, KMS4034, effects on inflammatory and neuropathic pain likely via modulating TRPV1 in mice

BACKGROUND Curcumin, the active ingredient of turmeric (Curcuma longa), has a wide range of beneficial effects including anti-inflammation and analgesia. However, poor bioavailability of curcumin hinders its clinical application. To overcome this limitation, we modified the structure of curcumin and synthesized new derivatives with favourable pharmacokinetic profiles. Recently, curcumin has been shown to have an antagonizing effect on transient receptor potential vanilloid type 1 (TRPV1) ion channels. We investigated the antinociceptive activity of KMS4034 which had the most favourable pharmacokinetics among the tested curcumin derivatives. METHODS To evaluate the mechanism of the antinociceptive effects of KMS4034, capsaicin (I(CAP))- and heat (I(heat))-induced currents in TRPV1 expressing HEK293 cells were observed after the application of KMS4034. Nociceptive behavioural measurement using the hot-plate test, formalin test, and chronic constriction injury (CCI) model were evaluated in mice. Also, calcitonin gene-related peptide (CGRP) was stained immunohistochemically in the L4/5 dorsal horns in mice with neuropathic pain. RESULTS I(CAP) (P<0.01) and I(heat) (P<0.05) of TRPV1 were significantly blocked by 10 μM KMS4034. Behaviourally, noticeable antinociceptive effects after 10 mg kg(-1) of KMS4034 treatment were observed in the first (P<0.05) and second phases (P<0.05) of the formalin and hot-plate tests. The mechanical threshold of CCI mice treated with 10 mg kg(-1) KMS4034 was significantly increased compared with control. Immunohistochemical CGRP expression was decreased in the lamina I-II of the lumbar dorsal horns in KMS4034-treated CCI mice compared with the control (P<0.05). CONCLUSIONS KMS4034 may be an effective analgesic for various pain conditions.

Only tetracaine and not other local anaesthetics induce apoptosis in rat cortical astrocytes

BACKGROUND The potential risks of neurotoxicity due to local anaesthetics after regional anaesthesia have been suggested recently. To evaluate the neurotoxicity of commonly used local anaesthetics, primary cultured rat cortical astrocytes were treated with lidocaine, ropivacaine, bupivacaine, levobupivacaine, and tetracaine. METHODS Cell death after local anaesthetic treatment was evaluated with a lactate dehydrogenase (LDH) assay. To examine the mechanisms of cell death, reactive oxygen species (ROS) measurement and western blots of poly-ADP ribose polymerase (PARP), procaspase-3, and mitogen-activated protein kinases family members were performed. RESULTS Of the local anaesthetics, which were applied at <1 mM for 18 h, only tetracaine significantly increased LDH leakage (P<0.05) and cell death in a dose- and time-dependent manner. Hoechst 33258-propidium iodide staining and western blots with PARP and procaspase-3 antibodies suggested that tetracaine induced apoptosis. ROS levels increased 2-fold at 30 min after tetracaine treatment compared with the control and then decreased. The antioxidants, N-acetylcysteine and trolox, markedly inhibited tetracaine-induced apoptosis. CONCLUSIONS Tetracaine induced apoptosis through ROS generation. Further studies focusing on the neurotoxicity of tetracaine are needed.

Comparison of reversal with neostigmine of low-dose rocuronium vs. reversal with sugammadex of high-dose rocuronium for a short procedure

Some short procedures require deep neuromuscular blockade, which needs to be reversed at the end of the procedure. Forty‐four patients undergoing elective laryngeal micro‐surgery were randomly allocated into two groups: rocuronium 0.45 mg.kg−1 with neostigmine (50 μg.kg−1 with glycopyrrolate 10 μg.kg−1) reversal (moderate block group) vs. rocuronium 0.90 mg.kg−1 with sugammadex (4 mg.kg−1) reversal (deep block group). The primary outcome was the intubating conditions during laryngoscopy secondary outcomes included recovery of neuromuscular block; conditions for tracheal intubation; satisfaction score as determined by the surgeon; onset of neuromuscular block; and postoperative sore throat. The onset of neuromuscular block was more rapid, and intubation conditions and ease of intra‐operative laryngoscopy were more favourable, and the satisfaction score was lower in the moderate block group compared with the deep block group. No difference was found in the incidence of postoperative sore throat. In laryngeal micro‐surgery, the use of rocuronium 0.9 mg.kg−1 with sugammadex for reversal was associated with better surgical conditions and a shorter recovery time than rocuronium 0.45 mg.kg−1 with neostigmine.

Dexmedetomidine Injection during Strabismus Surgery Reduces Emergence Agitation without Increasing the Oculocardiac Reflex in Children: A Randomized Controlled Trial.

Objective Dexmedetomidine is known to reduce the incidence of emergence agitation, which is a common complication after inhalational anesthesia like sevoflurane or desflurane in children. However, the dose of dexmedetomidine used for this purpose is reported variously and the most effective dose is not known. In this study, we tried to find the most effective dose of dexmedetomidine to reduce the incidence of emergence agitation in children undergoing strabismus surgery without the complications like oculocardiac reflex (OCR) or postoperative vomiting. Methods We randomized 103 pediatric patients aged 2–6 years and undergoing elective strabismus surgery into four groups. Anesthesia was induced with sevoflurane and maintained with desflurane. At the start of induction, dexmedetomidine, delivered at 0.25, 0.5, or 1 μg/kg, or saline was infused intravenously in the D0.25, D0.5, D1 groups, respectively. The primary outcome measure was the incidence of emergence agitation and the secondary outcome measure was the incidence of intraoperative OCR, postoperative vomiting, and desaturation events. Results The incidence of emergence agitation was 60, 48, 44, and 21% (P = 0.005) and the incidence of intraoperative OCR was 36, 36, 36, and 37% (P = 0.988) in the control, D0.25, D0.5, and D1 groups, respectively. And, postoperative vomiting rate and desaturation events were low in the all groups. Conclusion Dexmedetomidine decreased the incidence of emergence agitation without increasing intraoperative oculocardiac reflex. Dexmedetomidine delivered at 1 μg/kg was more effective at reducing emergence agitation than lower doses in children undergoing strabismus surgery under desflurane anesthesia. Trial Registration Clinical Research Information Service KCT0000141

Optimum dose of neostigmine to reverse shallow neuromuscular blockade with rocuronium and cisatracurium

We examined the use of neostigmine for reversing shallow (defined as train‐of‐four ratio of 0.5), cisatracurium‐ and rocuronium‐induced neuromuscular block in 112 patients, by use of 0 μg.kg−1, 10 μg.kg−1, 20 μg.kg−1 or 40 μg.kg−1 dose of neostigmine for reversal. The times from neostigmine administration to train‐of‐four ratios of 0.7, 0.9 and 1.0 were evaluated. Analysis of variance showed that the duration of action was significantly longer after cisatracurium compared with rocuronium. The time to reach a train‐of‐four ratio of 1.0 was significantly shorter with neostigmine 40 μg.kg−1 compared with lower neostigmine doses, and at this dose the time did not differ between cisatracurium and rocuronium. The recovery time from a train‐of‐four ratio of 0.5–1.0 did not differ between cisatracurium and rocuronium, and was significantly shortened by the administration of neostigmine. We conclude that a neostigmine dose of 40 μg.kg−1 was the most effective at reducing recovery time after neuromuscular blockade.

Timing of reversal with respect to three nerve stimulator end-points from cisatracurium-induced neuromuscular block.

After elective ear surgery with cisatracurium neuromuscular blockade, 48 adults were randomly assigned to receive neostigmine: (a) at appearance of the fourth twitch of a ‘train‐of‐four’; (b) at loss of fade to train‐of‐four; or (c) at loss of fade to double‐burst stimulation, all monitored using a TOF‐Watch SX® on one arm. For each of these conditions, the recovery from train‐of‐four (TOF) ratio was measured in parallel objectively using a TOF‐Watch SX placed on the contralateral arm. The median (IQR [range]) time from administration of reversal to a train‐of‐four ratio ≥ 0.9 was 11 (9–15.5 [2–28]) min, 8 (4–13.5 [1–25]) min and 7 (4–10 [2–15]) min in the three groups, respectively. This recovery time was significantly shorter when reversal was given at loss of fade to double‐burst stimulation (c), than when given at the appearance of the fourth twitch (a), p = 0.046. However, the total time to extubation may be unaffected as it takes longer for fade to be lost after double‐burst stimulation than for four twitches subjectively to appear.

Comparison of the efficacy and safety of 2% lidocaine HCl with different epinephrine concentration for local anesthesia in participants undergoing surgical extraction of impacted mandibular third molars: A multicenter, randomized, double-blind, crossover, phase IV trial

Background: The most commonly impacted tooth is the third molar. An impacted third molar can ultimately cause acute pain, infection, tumors, cysts, caries, periodontal disease, and loss of adjacent teeth. Local anesthesia is employed for removing the third molar. This study aimed to evaluate the efficacy and safety of 2% lidocaine with 1:80,000 or 1:200,000 epinephrine for surgical extraction of bilateral impacted mandibular third molars. Methods: Sixty-five healthy participants underwent surgical extraction of bilateral impacted mandibular third molars in 2 separate visits while under local anesthesia with 2% lidocaine with different epinephrine concentration (1:80,000 or 1:200,000) in a double-blind, randomized, crossover trial. Visual analog scale pain scores obtained immediately after surgical extraction were primarily evaluated for the 2 groups receiving different epinephrine concentrations. Visual analog scale pain scores were obtained 2, 4, and 6 hours after administering an anesthetic. Onset and duration of analgesia, onset of pain, intraoperative bleeding, operators and participants overall satisfaction, drug dosage, and hemodynamic parameters were evaluated for the 2 groups. Results: There were no statistically significant differences between the 2 groups in any measurements except hemodynamic factors (P >.05). Changes in systolic blood pressure and heart rate following anesthetic administration were significantly greater in the group receiving 1:80,000 epinephrine than in that receiving 1:200,000 epinephrine (P ⩽.01). Conclusion: The difference in epinephrine concentration between 1:80,000 and 1:200,000 in 2% lidocaine liquid does not affect the medical efficacy of the anesthetic. Furthermore, 2% lidocaine with 1:200,000 epinephrine has better safety with regard to hemodynamic parameters than 2% lidocaine with 1:80,000 epinephrine. Therefore, we suggest using 2% lidocaine with 1:200,000 epinephrine rather than 2% lidocaine with 1:80,000 epinephrine for surgical extraction of impacted mandibular third molars in hemodynamically unstable patients.