General anesthesia using propofol infusion for implantation of an implantable cardioverter defibrillator in a pediatric patient with Andersen-Tawil syndrome: a case report

Andersen-Tawil syndrome (ATS) is a rare genetic disease characterized by a triad of episodic flaccid muscle weakness, ventricular arrhythmias, and physical anomalies. ATS patients have various cardiac arrhythmias that can cause sudden death. Implantation of an implantable cardioverter-defibrillator (ICD) is required when life-threatening cardiac arrhythmias do not respond to medical treatment. An 11-year-old girl underwent surgery for an ICD implantation. For general anesthesia in ATS patients, anesthesiologists should focus on the potentially difficult airway, serious cardiac arrhythmias, such as ventricular tachycardia (VT), and delayed recovery from neuromuscular blockade. We followed the difficult airway algorithm, avoided drugs that can precipitate QT prolongation and fatal cardiac arrhythmias, and tried to maintain normoxia, normocarbia, normothermia, normoglycemia, and pain control for prevention of sympathetic stimulation. We report the successful application of general anesthesia for ICD implantation in a pediatric patient with ATS and recurrent VT.

Antipsychotics for patients with pain

Going back to basics prior to mentioning the use of antipsychotics in patients with pain, the International Association for the Study of Pain (IASP) definition of pain can be summarized as an unpleasant experience, composed of sensory experience caused by actual tissue damage and/or emotional experience caused by potential tissue damage. Less used than antidepressants, antipsychotics have also been used for treating this unpleasant experience as adjuvant analgesics without sufficient evidence from research. Because recently developed atypical antipsychotics reduce the adverse reactions of extrapyramidal symptoms, such as acute dystonia, pseudo-parkinsonism, akathisia, and tardive dyskinesia caused by typical antipsychotics, they are expected to be used more frequently in various painful conditions, while increasing the risk of metabolic syndromes (weight gain, diabetes, and dyslipidemia). Various antipsychotics have different neurotransmitter receptor affinities for dopamine (D), 5-hydroxytryptamine (5-HT), adrenergic (α), histamine (H), and muscarinic (M) receptors. Atypical antipsychotics antagonize transient, weak D₂ receptor bindings with strong binding to the 5-HT(2A) receptor, while typical antipsychotics block long-lasting, tight D₂ receptor binding. On the contrary, antidepressants in the field of pain management also block the reuptake of similar receptors, mainly on the 5-HT and, next, on the norepinephrine, but rarely on the D receptors. Antipsychotics have been used for treating positive symptoms, such as delusion, hallucination, disorganized thought and behavior, perception disturbance, and inappropriate emotion, rather than the negative, cognitive, and affective symptoms of psychosis. Therefore, an antipsychotic may be prescribed in pain patients with positive symptoms of psychosis during or after controlling all sensory components.

Successful removal of permanent spinal cord stimulators in patients with complex regional pain syndrome after complete relief of pain

BACKGROUND: It is uncommon for patients who have received a permanent implant to remove the spinal cord stimulator (SCS) after discontinuation of medication in complex regional pain syndrome (CRPS) due to their completely painless state. This study evaluated CRPS patients who successfully removed their SCSs. METHODS: This 10-year retrospective study was performed on patients who had received the permanent implantation of an SCS and had removed it 6 months after discontinuation of stimulation, while halting all medications for neuropathic pain. Age, sex, duration of implantation, site and type of CRPS, and their return to work were compared between the removal and non-removal groups. RESULTS: Five (12.5%, M/F = 4/1) of 40 patients (M/F = 33/7) successfully removed the permanent implant. The mean age was younger in the removal group (27.2 ± 6.4 vs. 43.5 ± 10.7 years, P < 0.01). The mean duration of implantation in the removal group was 34.4 ± 18.2 months. Two of 15 patients (13.3%) and 3 of 25 patients (12%) who had upper and lower extremity pain, respectively, had removed the implant. The implants could be removed in 5 of 27 patients (18.5%) with CRPS type 1 (P < 0.01). All 5 patients (100%) who removed their SCS returned to work, while only 5 of 35 (14.3%) in the non-removal group did (P < 0.01). CONCLUSIONS: Even though this study had limited data, younger patients with CRPS type 1 could remove their SCSs within a 5-year period and return to work with complete pain relief.

Propofol promotes osteoclastic bone resorption by increasing DC-STAMP expression

BACKGROUND: Propofol is an intravenous anesthetic which has antioxidant effects due to its similarity in molecular structure to α-tocopherol. It has been reported that α-tocopherol increases osteoclast fusion and bone resorption. Here, we investigated the effects of propofol on signaling pathways of osteoclastogenic gene expression, as well as osteoclastogenesis and bone resorption using bone marrow-derived macrophages (BMMs). METHODS: BMMs were cultured with macrophage colony-stimulating factor (M-CSF) alone or M-CSF plus receptor activator of nuclear factor kappa B ligand (RANKL) in the presence of propofol (0–50 µM) for 4 days. Mature osteoclasts were stained for tartrate-resistant acid phosphatase (TRAP) and the numbers of TRAP-positive multinucleated osteoclasts were counted. To examine the resorption activities of osteoclasts, a bone resorption assay was performed. To identify the mechanism of action of propofol on the formation of multinucleated osteoclasts, we focused on dendritic cell-specific transmembrane protein (DC-STAMP), a protein essential for pre-osteoclastic cell fusion. RESULTS: Propofol increased the formation of TRAP-positive multinucleated osteoclasts. In addition, the bone resorption assay revealed that propofol increased the bone resorption area on dentin discs. The mRNA expression of DC-STAMP was upregulated most strongly in the presence of both RANKL and propofol. However, SB203580, a p38 inhibitor, significantly suppressed the propofol/RANKL-induced increase in mRNA expression of DC-STAMP. CONCLUSION: We have demonstrated that propofol enhances osteoclast differentiation and maturation, and subsequently increases bone resorption. Additionally, we identified the regulatory pathway underlying osteoclast cell-cell fusion, which was enhanced by propofol through p38-mediated DC-STAMP expression.

Medications for osteoporotic pain

No abstract available.

Dexmedetomidine attenuates H₂O₂-induced cell death in human osteoblasts

BACKGROUND: Reactive oxygen species play critical roles in homeostasis and cell signaling. Dexmedetomidine, a specific agonist of the α₂-adrenoceptor, has been commonly used for sedation, and it has been reported to have a protective effect against oxidative stress. In this study, we investigated whether dexmedetomidine has a protective effect against H₂O₂-induced oxidative stress and the mechanism of H₂O₂-induced cell death in normal human fetal osteoblast (hFOB) cells. METHODS: Cells were divided into three groups: control group—cells were incubated in normoxia without dexmedetomidine, hydrogen peroxide (H2O2) group—cells were exposed to H₂O₂ (200 µM) for 2 h, and Dex/H₂O₂ group—cells were pretreated with dexmedetomidine (5 µM) for 2 h then exposed to H₂O₂ (200 µM) for 2 h. Cell viability and apoptosis were evaluated. Osteoblast maturation was determined by assaying bone nodular mineralization. Expression levels of bone-related proteins were determined by western blot. RESULTS: Cell viability was significantly decreased in the H₂O₂ group compared with the control group, and this effect was improved by dexmedetomidine. The Hoechst 33342 and Annexin-V FITC/PI staining revealed that dexmedetomidine effectively decreased H₂O₂-induced hFOB cell apoptosis. Dexmedetomidine enhanced the mineralization of hFOB cells when compared to the H₂O₂ group. In western blot analysis, bone-related protein was increased in the Dex/H₂O₂ group. CONCLUSIONS: We demonstrated the potential therapeutic value of dexmedetomidine in H₂O₂-induced oxidative stress by inhibiting apoptosis and enhancing osteoblast activity. Additionally, the current investigation could be evidence to support the antioxidant potential of dexmedetomidine in vitro.

Alteration of laboratory findings after radiofrequency ablation of hepatocellular carcinoma: relationship to severity of the underlying liver disease and the ablation volume

BACKGROUND/AIMS: To investigate sequential changes in laboratory markers after radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) and the relationship of these changes to the severity of the underlying liver disease. METHODS: This retrospective analysis included 65 patients (44 males, 21 females) who underwent RFA of HCC. Hematologic and biochemical markers were assessed at the pre-RFA period and 1 day, 2-3 days, and 1-2 weeks after RFA. We classified the subjects into two groups: Child-Pugh A (n=41) and Child-Pugh B (n=24). The ablative margin volume (AMV) of each patient was measured. We analyzed the changes in laboratory profiles from the baseline, and investigated whether these laboratory changes were correlated with the AMV and the Child-Pugh classification. RESULTS: Most of the laboratory values peaked at 2-3 days after RFA. AMV was significantly correlated with changes in WBC count, hemoglobin level, and serum total bilirubin level (Pearson's correlation coefficient, 0.324-0.453; P<0.05). The alanine aminotransferase (ALT) level varied significantly over time (P=0.023). CONCLUSIONS: Most of the measured laboratory markers changed from baseline, peaking at 2-3 days. The ALT level was the only parameter for which there was a significant difference after RFA between Child-Pugh A and B patients: it increased significantly more in the Child-Pugh A patients.

Infusion Methods for Continuous Interscalene Brachial Plexus Block for Postoperative Pain Control after Arthroscopic Rotator Cuff Repair

BACKGROUND: Infusion methods during regional analgesia using perineural catheters may influence the quality of postoperative analgesia. This study was conducted to compare the effects of combined or bolus-only infusion of 0.2% ropivacaine on the postoperative analgesia in interscalene brachial plexus block (ISBPB) with perineural catheterization. METHODS: Patients scheduled for arthroscopic rotator cuff repair were divided into two groups, one that would receive a combined infusion (group C, n = 32), and one that would receive intermittent infusion (group I, n = 32). A perineural catheter was inserted into the interscalene brachial plexus (ISBP) using ultrasound (US) and nerve stimulation, and 10 ml of 0.2% ropivacaine was administered. After the operation, group C received a continuous infusion of 4 ml/h, and a 4 ml bolus with a lockout interval of 60 min. Group I received only a 4 ml bolus, and the lockout interval was 30 min. Postoperative pain by the numeric rating scale (NRS) and the forearm muscle tone by the manual muscle test (MMT) were checked and evaluated at the following timepoints: preoperative, and postoperative 1, 4, 12, 24, 36, and 48 h. Supplemental opioid requirements, total consumed dose of local anesthetic, and adverse effects were compared between the two groups. RESULTS: Sixty-four patients completed the study and the postoperative values such as operation time, time to discharge, and operation site were comparable. There were no differences in NRS scores and supplemental opioid requirements between the two groups. The MMT scores of group I at 4 and 12 h after surgery were significantly higher than those of group C (P < 0.05). The total consumed dose of local anesthetic was significantly lower in group I than in group C (P < 0.05). The adverse effects were not different between the groups. CONCLUSIONS: The bolus-only administration of 0.2% ropivacaine provided a similar analgesic effect with a lower total volume of local anesthetic and decreased motor weakness compared to combined infusion. Therefore, bolus-only administration is an effective postoperative analgesic method in ISBPB with perineural catheterization after rotator cuff repair.

Mechanical Antiallodynic Effect of Intrathecal Nefopam in a Rat Neuropathic Pain Model

Nefopam has a pharmacologic profile distinct from that of opioids or other anti-inflammatory drugs. Several recent studies demonstrate that nefopam has a mechanism of action similar to those of anti-depressants and anticonvulsants for treating neuropathic pain. The present study investigates the mechanical antiallodynic effect of nefopam using immunohistochemical study and western blot analysis in a rat neuropathic pain model. Twenty-eight male Sprague-Dawley rats were subjected to left fifth lumbar (L5) spinal nerve ligation and intrathecal catheter implantation, procedures which were not performed on the 7 male Sprague-Dawley rats in the sham surgery group (group S). Nefopam, either 10 or 100 microg/kg (group N10 or N100, respectively), and normal saline (group C) were intrathecally administered into the catheter every day for 14 days. The mechanical allodynic threshold of intrathecal nefopam was measured using a dynamic plantar aesthesiometer. Immunohistochemistry targeting cluster of differentiation molecule 11b (CD11b) and glial fibrillary acidic protein (GFAP) was performed on the harvested spinal cord at the level of L5. Extracellular signal-regulated kinase 1/2 (ERK 1/2) and cyclic adenosine monophosphate response element binding protein (CREB) were measured using western blot analysis. The N10 and N100 groups showed improved mechanical allodynic threshold, reduced CD11b and GFAP expression, and attenuated ERK 1/2 and CREB in the affected L5 spinal cord. In conclusion, intrathecal nefopam reduced mechanical allodynia in a rat neuropathic pain model. Its mechanical antiallodynic effect is associated with inhibition of glial activation and suppression of the transcription factors' mitogen-activated protein kinases in the spinal cord.

Medications in Treatment of Postherpetic Neuralgia

No abstract available.

Foreign Body Removal at Right Main Bronchus in A Neonate / 대한구급학회지

Foreign body in the airway could be a life-threatening risk, especially for young pediatric patients. A 6-day old male patient with foreign body, which was located deep in the right main bronchus was being admitted. Although we tried three times to remove it with rigid bronchoscopic forceps under the general anesthesia, we failed. Before switching to surgical treatment, we changed the Trendelenburg position and tapped his back several times in order to alter the foreign body toward the forcep. Finally we were able to catch and extract the foreign body successfully. We suggest that back percussion with the Trendelenburg position is a useful solution to remove a foreign body within a deep airway.

Postoperative Orthostatic Intolerance and Gender Differences

No abstract available.

Optimal dose of dexmedetomidine for sedation during spinal anesthesia / 대한마취과학회지

BACKGROUND: Sedation in spinal anesthesia can reduce patient's anxiety and discomfort. Dexmedetomidine has a sedative, hypnotic, analgesic, and minimal respiratory depression effect. However, use of the dexmedetomidine is associated with prolonged recovery. This study was designed to investigate the optimal dose of intravenous dexmedetomidine for proper sedation with minimal recovery time in spinal anesthesia. METHODS: One hundred twenty eight patients, aged 20-70 years (58.8 +/- 0.7), were recruited. After performing the spinal anesthesia with hyperbaric bupivacaine (13 mg), a loading dose of dexmedetomidine (1 microg/kg) was administered for 10 min, followed by the maintenance infusion of the following: Group A (n = 33; normal saline), Group B (n = 35; dexmedetomidine 0.2 microg/kg/hr), and Group C (n = 39; dexmedetomidine 0.4 microg/kg/hr). Heart rate, blood pressure, and the bispectral index score (BIS) were recorded during the operation. In the recovery room, modified aldrete score (MAS) was measured. RESULTS: There were no significant differences in mean blood pressure and heart rate among the three groups. BIS was not significantly different among the three groups from baseline to 60 min after the infusion of dexmedetomidine. BIS were significantly increased in Group A after 70 and 80 min, and Group A and B after 90, 100, 110 min of dexmedetomidine infusion (P < 0.05). MAS was higher in Group A as compared to Group B and C, within 30 min after admission in the recovery room (P < 0.05). CONCLUSIONS: The loading dose (1 microg/kg/10 min) of dexmedetomidine was sufficient for surgery of less than 60 min. Dexmedetomidine infusion followed by maintenance dose (0.2 microg/kg/hr) was sufficient for surgery within 90 min.

Central Venous Catheter Misplaced in the Innominate Vein after Penetrating the Left Subclavian Vein in a Neonate: A Case Report / 대한구급학회지

In the pediatric ICU and operating room, a central venous catheter (CVC) provides accurate hemodynamic information and serves as a reliable route for the administration of vasoactive drugs, fluids and allogeneic blood products. The placement of CVC is associated with a complication rate of 0.4% to 20%, including hemothorax, pneumothorax, thrombosis, infection and cardiac tamponade. We describe a case of CVC being misplaced in the innominate vein after penetrating the subclavian vein during anesthesia induction for arterial switch operation. Our report discusses the mechanisms by which this mishap took place, and reviews the proper positions of the head, arm, thorax and safe depth of venipuncture for the placement of a CVC in neonates.

Radiation Safety for Pain Physicians

No abstract available.

Effects of etomidate on bispectral index scale and spectral entropy during induction of anesthesia by means of the raw electroencephalographic and electromyographic characteristics / 대한마취과학회지

BACKGROUND: Etomidate frequently induces myoclonus, so it may affect electromyographics (EMG). And EMG commonly has an effect on the bispectral index scale (BIS) and spectral entropy. This study was performed to compare the effect of etomidate on BIS, response entropy (RE) and state entropy (SE) during induction of anesthesia. METHODS: Fifty patients (ASA I or II) scheduled for elective surgery were included in this study. Anesthesia was induced with etomidate (0.3 mg/kg) and rocuronium (0.6 mg/kg). Patients also inhaled 4 vol% sevoflurane and 100% oxygen and, then intubated. BIS, RE, SE and Modified Observer's Assessment of Alertness/Sedation Scale (MOAA/S) were measured 4 times (before injection of etomidate [T0], at loss of eyelash reflex [T1], 90 seconds after rocuronium injection [T2], and after intubation [T3]). We also checked whether myoclonus occurred. RESULTS: Baseline values (T0) were 93.1 +/- 4.7 for BIS, 95.8 +/- 3.7 for RE and, 87.3 +/- 3.5 for SE. In comparison with T0, there were significantly differences in BIS (50.2 +/- 16.3), RE (76.8 +/- 18.5) and SE (66.3 +/- 17.4) at T1 (all P < 0.05). There were no significant differences at T2 and T3. Thirty one patients had myoclonus. At the occurrence of myoclonus, RE and SE values significantly increased but not BIS (P < 0.05). CONCLUSIONS: In patients with myoclonus, at the loss of consciousness, spectral entropy did not decrease where as BIS did, suggesting that BIS may evaluate hypnotic levels better than spectral entropy during induction of anesthesia with etomidate.

The median effective effect-site concentration of remifentanil for minimizing the cardiovascular changes to endotracheal intubation during desflurane anesthesia in pediatric patients / 대한마취과학회지

BACKGROUND: Desflurane has the most rapid onset and offset of action among the volatile anesthetic agents used for general anesthesia, but it can cause airway reactivity, tachycardia, and hypertension during induction, especially in pediatric patients. This study was designed to determine a median effective effect-site concentration (EC50) of remifentanil to prevent the cardiovascular changes due to tracheal intubation during the 1 minimum alveolar concentration (MAC) desflurane inhalation, which was required to prevent movement in response to a noxious stimulus in 50% of subjects, in pediatric patients. METHODS: Twenty-four pediatric patients between the ages 5-15 years were enrolled in this study. We injected thiopental intravenously, at the same time remifentanil was infused by Target Controlled Infusion (TCI) device. When the target effect-site concentration (Ce) of remifentanil reached a preset level, desflurane was administrated through the facial mask. Then, we assessed the signs of desflurane related airway reactivity and cardiovascular changes for 2 min. The up-and-down criteria was a 20% change in systolic blood pressure (SBP) and a heart rate (HR) between just prior to intubation and 1 min after intubation. The EC50 of remifentanil was calculated from 8 independent pairs using Dixon's up-and-down method. RESULTS: We studied 24 pediatric patients in range of 1-5 ng/ml of the Ce of remifentanil. No patient showed airway reactivity during the study. The EC50 of remifentanil to suppress the hemodynamic changes after tracheal intubation during desflurane anesthesia was calculated as 3.4 +/- 0.9 ng/ml. CONCLUSIONS: In pediatric anesthesia, the EC50 of remifentanil to minimize the cardiovascular changes due to tracheal intubation during 1 MAC desflurane anesthesia was 3.4 +/- 0.9 ng/ml.

The proper effect site concentration of remifentanil for prevention of myoclonus after etomidate injection / 대한마취과학회지

BACKGROUND: Etomidate frequently induces myoclonus when administered intravenously with bolus injection during anesthetic induction. This can be bothersome for the anesthesiologist. The dose of remifentanil appropriate for preventing myoclonus without side effects was investigated. METHODS: All patients with American Society of Anesthesiologists (ASA) physical status I-III were divided into three groups (n = 33 per group) according to the pretreatment effect site concentration of remifentanil (Ultiva, Glaxo-Wellcome, Munchen, Germany) of 0, 2 or 4 ng/ml (Group N: 0 ng/ml, Group R: 2 ng/ml, Group Q: 4 ng/ml) by a target controlled infusion (TCI) system. After a 0.3 mg/kg dose of etomidate was injected intravenously for over 1 minute for anesthetic induction, myoclonus was observed. Before the etomidate injection, the patients were pretreated with remifentanil and their side effects were monitored. RESULTS: The number of patients showing myoclonus was significantly different among the groups. The incidence of myoclonus was 81%, 12% and 0% (groups N, R, and Q, respectively, P < 0.01). Side effects including bradycardia and hypotension did not occur in either Group R or Q. Chest wall rigidity occured in 45% of patients in Group Q. CONCLUSIONS: Administration with a 2 ng/ml effect site concentration of remifentanil could reduce the incidence of myoclonus caused by etomidate bolus injection without chest wall rigidity.

Dexmedetomidine does not produce vasocontraction on human isolated gastroepiploic artery / 대한마취과학회지

BACKGROUND: Recently, the addition of dexmedetomidine to sedation regimens after cardiac surgery had been reported and there is a possibility that dexmedetomidine can cause vasoconstriction. Vasopressin has been used as a prophylactic treatment for refractory vasodilatory shock during coronary artery bypass graft (CABG). Also, vasopressin may play an important role in initiating spasms at the graft artery. Here we evaluate the direct effect of dexmedetomidine on isolated human gastroepiploic arteries and the synergistic effect of dexmedetomidine and vasopressin. METHODS: Discarded gastroepiploic arteries from elective subtotal gastrectomy (n = 10) were used in this study. We measured the level of contraction in isolated human gastroepiploic arteries induced by increasing concentrations of dexmedetomidine (10(-10) to 10(-6) M) with or without vasopressin (10(-10), 10(-9) M). Arterial contractions caused by increasing concentrations of vasopressin (10(-10) to 10(-7.5) M) with or without dexmedetomidine (10(-9), 10(-7) M) were also measured in the tissue samples. RESULTS: Supraclinical concentrations of dexmedetomidine elicited contractions at concentrations of 10(-7) M and 10(-6) M (P < 0.05 versus resting tension). The same concentrations of dexmedetomidine (10(-7), 10(-6) M) significantly enhanced vasopressin-induced contractions (P < 0.05 versus vasopressin-induced contraction). Vasopressin produced concentration-dependent contractions and vasopressin (10(-10), 10(-9.5), 10(-9) M) also increased the intensity of dexmedetomidine (10(-7) M) induced contractions. CONCLUSIONS: There was a synergistic effect between supraclinical doses of dexmedetomidine and vasopressin on the degree of contraction in isolated human gastroepiploic arteries. However, a sedative dose of dexmedetomidine (clinical dose: 0.2-0.7 microg/kg/hr, plasma concentration: 0.36-1.25 ng/ml) did not enhance vasopressin induced-contraction in isolated human gastroepiploic arteries.

Anesthetic management of a neonate with giant bronchopulmonary sequestration: A case report

Lung isolation in a neonate can be a challenge for the anesthesiologist. We report on our anesthetic experience with a neonate who had giant bronchopulmonary sequestration (BPS). The BPS was large enough to shift the mediastinum to the contralateral hemithorax. The trachea was immediately intubated after delivery and the lungs were mechanically ventilated in the neonatal intensive care unit. To prevent desaturation during the attempt of lung isolation, a 3 Fr Fogarty catheter was inserted into the trachea alongside the endotracheal tube without extubation. A fiberscope was then passed through the blocker port of a multiport adapter instead of the bronchoscopy port to minimize leakage by tightening the Touhy-Borst valve. Hypoxemia or leakage did not occur during the procedure. For early extubation, we provided caudal analgesia with ropivacaine and morphine. The giant BPS was successfully resected and the neonate was in excellent condition for early extubation. However, reintubation was needed for the pneumothorax caused by the inadequate placement of a chest drain 9 hours after extubation.