Neuroprotective effects of magnesium L-threonate in a hypoxic zebrafish model.

BACKGROUND: Hypoxia inhibits the uptake of glutamate (a major neurotransmitter in the brain closely related to cognitive function) into brain cells, and the initial response of cells to cortical hypoxia depends on glutamate. Previous studies have suggested that magnesium may have protective effects against hypoxic injuries. In particular, magnesium L-threonate (MgT) may increase magnesium ion concentrations in the brain better than MgSO4 and improve cognitive function. METHODS: We evaluated cell viability under hypoxic conditions in the MgT- and MgSO4-treated human SH-SY5Y neurons, in vivo behavior using the T-maze test following hypoxia in MgT-treated zebrafish, activity of brain mitochondrial dehydrogenase by 2,3,5-triphenyltetrazolium chloride (TTC) staining, and protein expression of the excitatory amino acid transporter (EAAT) 4 glutamate transporter by western blotting. RESULTS: Among the groups treated with hypoxia, cell viability significantly increased when pre-treated with 1 or 10 mM MgT (p = 0.009 and 0.026, respectively). Despite hypoxic insult, MgT-treated zebrafish showed preferences for the red compartment (p = 0.025 for distance and p = 0.007 for frequency of entries), suggesting memory preservation. TTC staining showed reduced cerebral infarction and preserved absorbance in the MgT-treated zebrafish brain after hypoxia (p = 0.010 compared to the hypoxia group). In addition, western blot showed upregulation of EAAT4 protein in the MgT treated group. CONCLUSIONS: Pre-treatment with MgT attenuated cell death and cerebral infarction due to hypoxia and protected cognitive function in zebrafish. In addition, MgT appeared to modulate expression of the glutamate transporter, EAAT4.

Evaluation of the Toxicity of Sugammadex in Zebrafish Larvae.

BACKGROUND: Sugammadex is a new neuromuscular blockade reversal agent. Recently, it has been used in patients under general anesthesia. However, sugammadex could be toxic to fetuses and pediatric patients under 3 years of age. In this study, we demonstrated the safety of sugammadex in fetuses, using zebrafish larvae. Furthermore, its neurotoxicity was evaluated using neuronal cell lines. METHODS: We used SH-SY5Y cells to determine the viability of neuronal cells treated with sugammadex. Zebrafish larvae were used to determine the teratogenic effects of sugammadex. RESULTS: Sugammadex showed no adverse effects on neuronal cells and zebrafish larvae. The survival rates of neuronal cells were not different in all concentrations. In addition, the heart formation of zebrafish embryos, which were exposed to various concentrations of sugammadex, were not different. CONCLUSION: This study demonstrated the feasibility of using sugammadex during pregnancy. However, further clinical studies will be required to extrapolate these results to humans.

Gap junction remodelling by chronic pressure overload is related to the increased susceptibility to atrial fibrillation in rat heart.

AIMS: Left atrial (LA) fibrosis caused by various pathological stimuli is a common finding. However, the difference of atrial remodelling via haemodynamic change in diverse cardiomyopathy has not been elucidated. METHODS AND RESULTS: Male Sprague-Dawley rats (6-8 weeks, n = 180) were randomly assigned to three groups and corresponding sham control groups: (i) ischaemic cardiomyopathy, (ii) left ventricular hypertrophy (LVH), and (iii) dilated cardiomyopathy. At 12 weeks after operation, atrial fibrillation (AF) inducibility and duration were assessed by in vivo burst transoesophageal pacing. Using the Langendorff apparatus, left ventricular (LV) function and pressure were measured. The expression of connexin-43 (Cx43) and alpha-smooth muscle actin (α-SMA) in atrial tissues was assessed by quantitative real-time polymerase chain reaction and immunohistochemical staining. Fibrosis was analysed by Masson's trichrome staining. Compared with controls, the LA weight/heart weight ratio was increased in the LVH group alone, and was significantly correlated with AF duration (P < 0.001, R = 0.388). Atrial fibrillation inducibility and duration were higher and longer only in the LVH group (P = 0.002, 0.079, respectively), and isolated LV diastolic dysfunction and elevated LV pressure were observed. Although α-SMA expression and fibrosis were increased in all three cardiomyopathy models, down-regulation of Cx43 expression in the LA was observed in the LVH group alone. CONCLUSION: Chronic pressure overload in the absence of LV systolic dysfunction resulted in LA hypertrophy and increased susceptibility to AF, which might be related to conduction abnormality via decreased expression and lateral distribution of Cx43 as well as interstitial fibrosis.

The protective effect of heat shock protein 70 (Hsp70) in atrial fibrillation in various cardiomyopathy conditions.

Heat shock proteins (Hsp) protect myocardial cells from acute stress such as atrial fibrillation (AF) and also from the chronic stress. It is not understood that Hsp70 can prevent AF under cardiomyopathy (CM) conditions. Therefore, we hypothesized that Hsp70 might beneficially influence on the occurrence of AF in CM conditions. We purposed to investigate the correlation between Hsp70 and the AF inducibility in various CM conditions that are unclear. We constructed four different animal models using Sprague-Dawley rats: an ischemic CM group (n = 12), a non-ischemic dilated CM group (n = 12), a pressure-overload hypertrophic CM group (n = 12), and a sham group (CON, n = 12). After 4-6 weeks of intervention animals, AF was induced acutely prior to hemodynamic studies. Hemodynamic data using the Langendorff technique and histologic evaluation were conducted sequentially in all animal groups. Afterwards, levels of Hsp70 were measured from atrial tissues by real-time polymerase chain reaction study. The hemodynamic data and histologic studies proved that each animal model was suitable to this study protocol. All CM groups showed that Hsp70 was elevated significantly compared to the control groups (P < 0.005). Among these CM groups, the TAC group revealed lower Hsp70 levels and higher induction rates of atrial fibrillation than the other groups (P < 0.005). The level of Hsp70 was elevated in all the CM models and it was negatively correlated with AF induction rate in sham group. However, we could not find correlation between Hsp70 and AF among the CM models.

Effects of health insurance on racial disparity in osteoporosis medication adherence.

OBJECTIVE: To explore whether racial disparity in osteoporosis drug therapy maintenance varies by health insurance coverage status. DESIGN: Longitudinal observation study. SETTING: Cleveland Clinic Health System (Cleveland, OH) from January 2006 to December 2009. PATIENTS: 3,901 black and white female Medicare beneficiaries starting osteoporosis drug therapy. INTERVENTION: Analysis of the health system's integrated electronic medical records. MAIN OUTCOME MEASURES: Drug therapy adherence (medication possession ratio ≥80%) for more than 12 of 15 surveillance units and occurrence of extended nonadherence gaps for at least two surveillance units in a row. RESULTS: Among patients with supplementary health insurance (n = 2,278), no difference was observed for drug therapy adherence ( P = 0.17) and extended nonadherence gaps ( P = 0.53) between black and white participants. When patients did not have supplementary health insurance (n = 1,623), blacks (36% [95% CI 28-47]) were less likely to adhere to drug therapy than whites (47% [38-57]; odds ratio [OR] 0.34 [95% CI 0.09-0.92], P = 0.004). Blacks (25% [19-32]) also were more likely to have an extended nonadherence gap episode than whites (18% [11-26]; OR 2.42 [1.13-3.50], P = 0.03). CONCLUSION: Similar to previous research on racial disparity in health services, racial disparity in osteoporosis drug therapy maintenance between black and white female older patients existed when supplementary health insurance was not affordable.

Protective Effect of Ulinastatin on Cognitive Function After Hypoxia.

Ulinastatin (UTI) has neuroprotective properties. Neurologic insults, including hypoxia and use of anesthetic agents, cause postoperative cognitive dysfunction and alter gamma-aminobutyric acid (GABA) function. This study aimed to assess whether UTI could preserve learning and memory using a zebrafish hypoxic behavior model and biomarkers. Zebrafish (6-8 months of age and 2.5-3.5 cm long) were divided into eight groups as follows: phosphate-buffered saline (PBS) control, hypoxia + PBS, UTI (10,000, 50,000, and 100,000 units/kg), and hypoxia with UTI (10,000, 50,000, and 100,000 units/kg) groups. The endpoints of the T-maze experiment included total time, distance moved, and frequency in target or opposite compartment. We also measured the degree of brain infarction using 2,3,5­triphenyltetrazolium chloride staining, assessed SA-ß-galactosidase activity, and examined GABAA receptor expression using real-time polymerase chain reaction. In a dose-dependent manner, UTI affected learning and memory in zebrafish. Despite hypoxia, 100,000 units/kg of UTI preserved preference (time and distance) for the target compartment. More than 50,000 units/kg of UTI also showed reduced hypoxia-induced brain infarction, decreased SA-ß-galactosidase levels, and upregulated GABAA receptors. This study demonstrated that the location of the GABAA receptor is affected by hypoxia or UTI.

Conscious Sedation Methods for Blepharoplasty in Day Surgery.

Midazolam and fentanyl, in combination, are the most commonly used medications for conscious sedation in day aesthetic surgeries. Dexmedetomidine is popularly used in the sedation protocol of our hospital due to its reduced respiratory depression. However, its sedation benefits in facial aesthetic surgeries, like blepharoplasty, have not been well-evaluated. We retrospectively compared individuals sedated with midazolam and fentanyl bolus injection (N = 137) and those sedated with dexmedetomidine infusion (N = 113) to determine which is more suitable for blepharoplasty with a mid-cheek lift. The total amount of local anesthetic (p < 0.001), postoperative pain (p = 0.004), ketoprofen administration (p = 0.028), and the number of hypoxia episodes (p < 0.001) and intraoperative hypertension (p = 0.003) were significantly lower in the dexmedetomidine group. Hypoxia severity (p < 0.001) and minor hematoma formation (p = 0.007) were also significantly lower in the dexmedetomidine group. Sedation with dexmedetomidine infusion is associated with less hematoma formation than sedation with midazolam and fentanyl bolus pattern due to hemodynamic stability and analgesic effects. Dexmedetomidine infusion may be a good alternate sedative for lower blepharoplasty.

Comprehensive feasibility evaluation of small-diameter 3D templated vascular graft via physical characterizations andin-vivoexperiments.

3D printing (3DP) technology for tissue engineering applications has been extensively studied for materials and processes. However, clinical application to the vascular system was limited owing to mechanical inconsistency and toxicity. Here, we characterized 3D templated artificial vascular grafts (3D grafts), which were fabricated by an integrative method involving 3DP, dip coating, and salt leaching method. The as-fabricated grafts were featured with micrometer-scale porosity enabling tissue-mimetic mechanical softness comparable with native blood vessels. In terms of mechanical properties and water permeability, the fabricated 3D grafts exhibited comparable or superior performances compared to the commercialized grafts. Furthermore, thein-vivostability of the 3D graft was validated through a toxicity test, and the small-diameter 3D graft was transplanted into a rat to confirm the implant's performance. Overall, the experimental results demonstrated the clinical feasibility of the 3D graft with retaining the mechanical biocompatibility and also revealed the possibility of patient-specific customization.

Intrathecal hydromorphone added to hyperbaric bupivacaine for postoperative pain relief after knee arthroscopic surgery: a prospective, randomised, controlled trial.

BACKGROUND AND OBJECTIVE: Adding opioid to spinal anaesthetic provides additional analgesia during the postoperative period. The purpose of this study was to determine the dose of intrathecal hydromorphone necessary to achieve postoperative pain relief after arthroscopic knee surgery. METHODS: In a prospective, double-blinded parallel, placebo-controlled manner, 60 patients who were undergoing unilateral knee arthroscopy randomly received unilateral spinal anaesthesia with 0.5% hyperbaric bupivacaine 6 mg combined with 0.0, 2.5, 5.0 or 10.0 µg per 0.05 ml hydromorphone. Fifteen patients were assigned to receive each dose. The visual analogue pain scores (VAPSs) were measured at 30 min and 2, 4, 6, 12 and 24 h postoperatively, and the side-effects of hydromorphone were recorded. RESULTS: The postoperative VAPSs at 4, 6 and 12 h for the 5 and 10 µg hydromorphone groups were significantly decreased, compared to the control group. The 2.5 µg hydromorphone group had lower VAPS only at 4 and 6 h postoperatively. Nausea was significantly increased in the 10 µg hydromorphone group (46.6%). CONCLUSION: The analgesic effects of 5 and 10 µg intrathecal hydromorphone provided satisfactory pain relief for 12 h postoperatively and nausea increased significantly in a dose-dependent manner.

Morphine attenuates endothelial cell adhesion molecules induced by the supernatant of LPS-stimulated colon cancer cells.

A large reservoir of bacterial lipopolysaccharide (LPS) is available in the colon and this could promote colon cancer metastasis by enhancing tumor cell adhesion, intravasation, and extravasation. Furthermore, adhesion molecules like ICAM-1, VCAM-1, and E-selectin play important roles in the adhesion of tumor cells to endothelium. This study was designed to determine whether morphine can attenuate the expressions of adhesion molecules up-regulated by the supernatant of LPS-stimulated HCT 116 colon cancer cells (LPS-Sup). In this study, we divided to three groups by cell-growth medium of human umbilical vascular endothelial cells (HUVECs): the control group was incubated in growth factor-free endothelial medium, the Sup group was incubated in the supernatant of HCT 116 cells (Sup), and the LPS-Sup group was incubated in LPS-Sup. To observe effect of morphine to the adhesion molecules expressions in the LPS-Sup group, we co-treated morphine with LPS or added it to LPS-Sup. Adhesion molecule expressions on HUVECs in all three groups were measured during incubation period. Consquentially, ICAM-1, VCAM-1, and E-selectin expressions on HUVECs were significantly lower when morphine was co-treated with LPS than not co-treated. Thus, we suggest that morphine affects the expressions of adhesion molecules primarily by attenuating LPS stimuli on tumor cells.

Morphine postconditioning attenuates ICAM-1 expression on endothelial cells.

The purpose of this study is to determine 1) whether morphine post condition (MPostC) can attenuate the intercellular adhesion molecules-1 (ICAM-1) expression after reoxygenation injury and 2) the subtype(s) of the opioid receptors (ORs) that are involved with MPostC. Human umbilical vein endothelial cells (HUVECs) were subjected to 6 hr anoxia followed by 12 hr reoxygenation. Three morphine concentrations (0.3, 3, 30 µM) were used to evaluate the protective effect of MPostC. We also investigated blockading the OR subtypes' effects on MPostC by using three antagonists (a µ-OR antagonist naloxone, a κ-OR antagonist nor-binaltorphimine, and a δ-OR antagonist naltrindole) and the inhibitor of protein kinase C (PKC) chelerythrine. As results, the ICAM-1 expression was significantly reduced in the MPostC (3, 30 µM) groups compared to the control group at 1, 6, 9, and 12 hours reoxygenation time. As a consequence, neutrophil adhesion was also decreased after MPostC. These effects were abolished by co administering chelerythrine, nor-binaltorphimine or naltrindole, but not with naloxone. In conclusion, it is assumed that MPostC could attenuate the expression of ICAM-1 on endothelial cells during reoxygenation via the κ and δ-OR (opioid receptor)-specific pathway, and this also involves a PKC-dependent pathway.

The Effect of Ulinastatin to the Learning and Memory in Zebrafish.

Previous study indicated that Ulinastatin (UTI) increased glutamine uptake by upregulation of glutamate transporters in astrocytes. These glutamate transporters have important role to improve cognitive function in hippocampus. In this study, we wanted to demonstrate whether UTI could improve learning and memory by using zebrafish behavior model and bio-markers. Zebrafish were 6-8 months of age and were 2.5-3.5 cm long. They were divided into four groups by control, 1X PBS-injected control, UTI 10,000, and 50,000 injected group. All PBS and UTI injected zebrafish were anesthetized by Tricainemethanesulphonate. We measured total time, distance moved, and frequency in each compartment of T-maze. We also measured the expression levels of glutamate transporter levels and cognitive bio-markers such as c-fos, c-jun, BDNF. UTI affected the learning and memory in zebrafish in a dose-dependent manner. In 50,000 unit/kg UTI-treated zebrafish, there were increases of time, distance, and frequency in target compartment. In 50,000 unit/kg UTI-treated zebrafish, there was an increase of time in target compartment. There was no difference among control, PBS-injected, and UTI 10,000 unit/kg-treated groups. EAAT4 glutamate transporter, c-fos and BDNF were significantly increased in 50,000 unit/kg UTI-treated group. UTI-enhanced learning and memory in zebrafish. The expressions of EAAT4 glutamate transporter, c- fos and BDNF in zebrafish were highly correlated may play a role.

Evaluation of 3D Templated Synthetic Vascular Graft Compared with Standard Graft in a Rat Model: Potential Use as an Artificial Vascular Graft in Cardiovascular Disease.

Although the number of vascular surgeries using vascular grafts is increasing, they are limited by vascular graft-related complications and size discrepancy. Current efforts to develop the ideal synthetic vascular graft for clinical application using tissue engineering or 3D printing are far from satisfactory. Therefore, we aimed to re-design the vascular graft with modified materials and 3D printing techniques and also demonstrated the improved applications of our new vascular graft clinically. We designed the 3D printed polyvinyl alcohol (PVA) templates according to the vessel size and shape, and these were dip-coated with salt-suspended thermoplastic polyurethane (TPU). Next, the core template was removed to obtain a customized porous TPU graft. The mechanical testing and cytotoxicity studies of the new synthetic 3D templated vascular grafts (3DT) were more appropriate compared with commercially available polytetrafluoroethylene (PTFE) grafts (ePTFE; standard graft, SG) for clinical use. Finally, we performed implantation of the 3DTs and SGs into the rat abdominal aorta as a patch technique. Four groups of the animal model (SG_7 days, SG_30 days, 3DT_7 days, and 3DT_30 days) were enrolled in this study. The abdominal aorta was surgically opened and sutured with SG or 3DT with 8/0 Prolene. The degree of endothelial cell activation, neovascularization, thrombus formation, calcification, inflammatory infiltrates, and fibrosis were analyzed histopathologically. There was significantly decreased thrombogenesis in the group treated with the 3DT for 30 days compared with the group treated with the SG for 7 and 30 days, and the 3DT for 7 days. In addition, the group treated with the 3DT for 30 days may also have shown increased postoperative endothelialization in the early stages. In conclusion, this study suggests the possibility of using the 3DT as an SG substitute in vascular surgery.

Effects of cranial electrotherapy stimulation on preoperative anxiety and blood pressure during anesthetic induction in patients with essential hypertension.

OBJECTIVE: Cranial electrotherapy stimulation (CES) is a non-invasive treatment that improves symptoms such as anxiety and pain. The purpose of this study was to analyze the effect of CES pretreatment on levels of preoperative anxiety, pain, and hemodynamic responses-especially changes in blood pressure-during anesthetic induction in patients with essential hypertension. METHODS: Eighty patients undergoing general anesthesia were randomly assigned to receive either no pretreatment (control group, n = 40) or CES pretreatment (CES group, n = 40). Anxiety scores, systolic and diastolic blood pressures, mean arterial pressure, and heart rate were measured in the general ward the evening before surgery, as well as in the preoperative holding area, operating room, and after intubation. Withdrawal responses to rocuronium injection were also measured. RESULTS: Anxiety scores in the operating room were significantly lower in the CES group. Withdrawal responses to rocuronium injection were also significantly lower in the CES group. There were no significant differences in hemodynamic values between the two groups. CONCLUSIONS: CES pretreatment reduces both preoperative anxiety levels and withdrawal responses to rocuronium injection. However, it does not have a significant effect on hemodynamic responses.

Non-intubated thoracoscopic bullectomy under sedation is safe and comfortable in the perioperative period.

BACKGROUND: Non-intubated thoracoscopic surgery can be performed under sedation using adjuvant regional anesthesia, however, the benefits of non-intubated thoracoscopic surgery under sedation have not yet been completely verified. In this study, we compare the perioperative safety and pain complaints of sedation without intubation in thoracoscopic bullectomy with that of conventional general anesthesia with double-lumen intubation and mechanical ventilation. METHODS: Forty-one patients with primary spontaneous pneumothorax who were scheduled for thoracoscopic bullectomy were enrolled in this study. Twenty-one patients were under sedation anesthesia (SA group) and 20 patients were under general anesthesia (GA group). In SA group, sedation was done with dexmedetomidine (a loading dose of 1 µg/kg for 10 min and then maintained in dosages of 0.3-1 µg/kg/h) and ketamine (2-4 mg/kg/h intraoperatively). Meanwhile, in GA group, induction with propofol and rocuronium, intubation with double lumen endotracheal tube and maintenance with 1.0-2.5% sevoflurane was done. In both groups, thoracoscopic bullectomy was performed in the same manner and all operations were conducted by single surgeon. Time for anesthesia [including emergence time and post-anesthesia care unit (PACU) recovery time] and operation, postoperative pain, sore throat, hoarseness, adverse events (nausea, vomiting, hypotension and bradycardia), dose of rescue analgesic drug used for 24 hours post-operatively and perioperative arterial blood gas analysis were recorded. RESULTS: The times for anesthesia, operation and emergence were significantly shorter in SA than GA. Incidence of sore throat were significantly lower in SA. The difference of other adverse events in the two groups was not significant. CONCLUSIONS: Our study demonstrated that compared to double-lumen intubation with general anesthesia, non-intubation with sedation for bullectomy for primary spontaneous pneumothorax was safe and efficient to reduce perioperative time.

Correlation between regional tissue perfusion saturation and lactate level during cardiopulmonary bypass.

BACKGROUND: Cardiopulmonary bypass (CPB) can cause systemic hypoperfusion, which remains undetected by routine monitoring of physiological parameters. Noninvasive tissue perfusion monitoring offers a clinical benefit by detecting low systemic perfusion. In this study, we tried to evaluate whether regional tissue perfusion saturation reflects systemic hypoperfusion during CPB. METHODS: This retrospective study included 29 patients with American Society of Anesthesiologists physical status II-III, who required cardiac surgery with CPB. We evaluated the correlations of serum lactate and delivery oxygen with organ perfusion values of peripheral tissue oxygen saturation and cerebral oxygen saturation. Data were recorded at different stages of CPB: T1 (pre-CPB), T2 (cooling), T3 (hypothermia), T4 (rewarming), and T5 (post-CPB). RESULTS: Lactate levels were elevated after CPB and up to weaning (P < 0.05). The levels of peripheral and tissue oxygen saturation decreased after the start of CPB (P < 0.05). Lactate levels were negatively correlated with peripheral tissue oxygen saturation levels at T4 (R = -0.384) and T5 (R = -0.370) and positively correlated with cerebral oxygen saturation at T3 (R = 0.445). Additionally, delivery oxygen was positively correlated with peripheral tissue oxygen saturation at T4 (R = 0.466). CONCLUSIONS: In this study, we demonstrated that peripheral tissue oxygen saturation can be a reliable tool for monitoring systemic hypoperfusion during CPB period. We also believe that peripheral tissue oxygen saturation is a valuable marker for detecting early stages of hypoperfusion during cardiac surgery.

The protective effect of hydromorphone to ischemia in rat glial cells.

BACKGROUND: Ischemic insults during operation can cause ischemic-reperfusion injuries in brain as well as memory impairments. Total intravenous anesthesia (TIVA) is the preferred anesthetic method in brain surgery, as it utilizes motor evoked potential monitoring. And the use of opioids is common in TIVA. However there are few studies about ischemic protective effect of opioids to glial cells. METHODS: We used mixed cultures of rat glial cells, which were harvested from the brain of 1-day old rat. We divided the experimental groups according to their hydromorphone conditioning period: (a) pre-culture, (b) per-culture, or (c) pre- and per-culture. We measured the levels of the reactive oxygen species (ROS) induced by tert-butyl hydroperoxide (TBH) using flow cytometry. The ROS levels in the glial cells were also measured after the administration of 100 nM hydromorphone and selective opioid receptor antagonists. RESULTS: The ROS levels were reduced in the hydromorphone-treated group, as compared to the control group (only TBH treated). There were no differences between pre-conditioned and per-conditioned groups. However, the ROS levels were more reduced in pre- and per-conditioned group compared to pre-conditioned or per-conditioned only groups. Furthermore, selective antagonists for the delta, kappa, or mu opioid receptor partially negated the hydromorphone effect. CONCLUSION: This study demonstrated that hydromorphone can have additional protective effects on oxidative stress when pre- and per-conditioning is combined. Furthermore we proved that µ, δ, κ opioid receptors participate in protective mechanism of hydromorphone to glial cells.

Non-intubated single port thoracoscopic procedure under local anesthesia with sedation for a 5-year-old girl.

Medical thoracoscopy is a feasible procedure for the diagnosis or treatment of thoracic diseases, and it can be performed under local anesthesia without tracheal intubation in cooperative adult patients. However, for younger than school aged patients, even simple procedures require general anesthesia with tracheal intubation. In this case report, we demonstrated the safe performance of a single port thoracoscopic procedure without tracheal intubation in a 5-year-old girl under local anesthesia and sedation. Local anesthesia around the site of a previous chest tube and sedation with intravenous (IV) dexmedetomidine and ketamine were applied. In the aspect of not only minimal injection of local anesthetics but also enhanced visualization of the thoracic structures, the non-intubated single port thoracoscopic surgery under local anesthesia with sedation was a good option for performing a simple thoracoscopic procedure in this 5-year-old patient.

Dexmedetomidine preconditioning attenuates Cisplatin-induced ototoxicity in zebrafish.

OBJECTIVES: Utilisation of high-frequency drills is known to increase noise induced hearing loss due to increasing the damages of inner ear cells. This study aimed to investigate whether preconditioning by using dexmedetomidine (DEX) decreased the occurrence of ischemia in inner cells of the ear. METHODS: We utilised a transgenic zebrafish line Brn3C, and the embryos were collected from breeding adult zebrafish. Five-day-old larvae were cultured at the density of 50 embryos, and the larvae were classified into 4 groups: control, cisplatin group, DEX group, and DEX+yohimbine; adrenoreceptor blocker group. The DEX group was categorised into 3 subgroups by dosage; 0.1, 1, and 10 µM. Preconditioning was performed for 150 minutes and then exposed to cisplatin for 6 hours. The experiment was performed in 7 replicates for each group and the number of hair cells in 3 parts of the neuromasts of each fish was determined. RESULTS: Hair cell apoptosis by cisplatin was attenuated more significantly in the DEX preconditioning group than in the control group. However, the preconditioning effects were not blocked by yohimbine. CONCLUSION: The results of this study suggest that hearing loss caused by vibration-induced noise could be reduced by using DEX and may occur through other mechanisms rather than adreno-receptors.

Anesthetic management of hypertensive crisis in a three-year-old patient with undiagnosed severe renal artery stenosis: a case report.

Pediatric hypertensive crisis is a potentially life threatening medical emergency, usually secondary to an underlying disease. Hypertension commonly occurs during general anesthesia, and is usually promptly and appropriately treated by anesthesiologists. However in children with severe, unexplained, or refractory hypertension, it has the potential to cause morbidity and even mortality in susceptible patients. We report an anesthetic management of an unexpected hypertensive crisis that developed during general anesthesia in a three-year-old girl with undiagnosed severe left renal artery stenosis.