Deep neuromuscular block improves angiographic image quality during endovascular coiling of unruptured cerebral aneurysm: a randomized clinical trial.

BACKGROUND: Neuromuscular block (NMB) used during general anesthesia induces transient skeletal muscle paralysis, but patient movements during endovascular coiling still occur to some degree. Compared with moderate NMB, deep NMB may further improve the intervention condition during endovascular coiling for unruptured cerebral aneurysms; however, little research has focused on the angiographic image quality. METHODS: This prospective, randomized, double-blind clinical trial included 58 patients treated for unruptured cerebral aneurysms with endovascular coiling under general anesthesia. Patients were randomly allocated to either the deep NMB group (post-tetanic count 1 or 2) or the moderate NMB group (train-of-four 1 or 2). The primary outcome was the proportion of patients with a satisfactory intervention condition assessed by surgeons after the procedure using a 5-point intervention condition rating scale (ICRS) from 1 (unable to obtain image) to 5 (optimal); ICRS 5 was defined as satisfactory. RESULTS: There were significantly more cases of satisfactory intervention condition in the deep NMB group than in the moderate NMB group (82.1% vs 51.7%, p=0.015). The frequency of each ICRS score was significantly different between the groups (ICRS 5/4/3/2/1: 23/5/0/0/0 vs 15/9/2/3/0, p=0.035). The incidence of major patient movement requiring rescue muscle relaxant was 10.3% in the moderate NMB group and 0% in the deep NMB group (p=0.237). The drugs used to maintain hemodynamic stability were not significantly different between the two groups. CONCLUSIONS: Deep NMB improves the intervention condition during endovascular coiling by improving the image quality.

Comparison of conventional and fibreoptic-guided advance of left-sided double-lumen tube during endobronchial intubation: A randomised controlled trial.

BACKGROUND: Postoperative sore throat and airway injuries are relatively common after double-lumen tube (DLT) intubation. OBJECTIVE: The current study aimed to evaluate the effects of fibreoptic-guided advance of DLT on postoperative sore throat and airway injuries associated with intubation. DESIGN: A randomised controlled study. SETTING: Tertiary hospital, Seongnam, Korea, from January 2018 to January 2019. PATIENTS: One hundred twenty three patients undergoing one-lung ventilation with a left-side DLT were randomised into two groups: 62 in the conventional group and 61 in the fibreoptic-guided group. INTERVENTION: After entering the glottis, the DLT was rotated left 90° and advanced blindly into the left main bronchus in the conventional group. In the fibreoptic-guided group, DLT was advanced into the main bronchus under the guide of fibreoptic bronchoscope, which had been passed through the bronchial lumen and inserted into the left main bronchus. MAIN OUTCOME MEASURES: The primary outcome was postoperative sore throat at 24 h after operation. The airway injuries were also examined using a bronchoscope during extubation. RESULTS: At postoperative 24 h, the fibreoptic-guided group showed lower pain score (P = 0.001) and lower incidence (risk ratio [95% CI]: 0.2 [0.1 to 0.5], P < 0.001) of sore throat, compared with the conventional group. Moreover, tracheal injury was more severe in the conventional group than in the fibreoptic group (P = 0.003). Vocal cord injuries also occurred less frequently in the fibreoptic-guided group (risk ratio [95% CI]: 0.4 [0.2 to 1.0], P = 0.036). CONCLUSION: The fibreoptic-guided advancement seems to reduce irritation to the airway, leading less postoperative complications. TRIAL REGISTRATION: ClinicalTrials.gov, registration number: NCT03368599.

Midazolam Premedication Facilitates Mask Ventilation During Induction of General Anesthesia: A Randomized Clinical Trial.

BACKGROUND: During induction of general anesthesia, proper mask ventilation is crucial for supplying sufficient oxygen to unconscious patients. Midazolam has a relaxing effect on airway muscles. We hypothesized that sedative premedication with midazolam would facilitate mask ventilation during anesthetic induction. METHODS: Patients undergoing elective surgery under general anesthesia were randomized into 2 groups. The midazolam group received midazolam premedication at the reception area, 3 minutes before transfer to the operating room. Patients in the control group were treated with normal saline as a placebo. The primary outcome was difficulty of mask ventilation during induction, as evaluated using the Warters scales. RESULTS: A total of 97 patients completed the analysis: 49 in the control group and 48 in the midazolam group. The patients in the midazolam group showed a significantly lower mask ventilation difficulty score on the Warters scale than that of the control group (mean [standard deviation], 0.92 [1.13] vs 0.19 [0.57]; estimated difference [95% confidence interval], 0.73 [0.37-1.09]; P < .001). The incidence of difficult mask ventilation (≥2 Warters scale) was significantly lower in the midazolam group than in the control group (risk ratio [95% confidence interval], 0.15 [0.03-0.72]; P = .015). CONCLUSIONS: This randomized clinical trial demonstrated that midazolam premedication enhanced mask ventilation during induction of general anesthesia.

The attenuation of neurological injury from the use of simvastatin after spinal cord ischemia-reperfusion injury in rats.

BACKGROUND: Spinal cord ischemic injury remains a serious complication of open surgical and endovascular aortic procedures. Simvastatin has been reported to be associated with neuroprotective effect after spinal cord ischemia-reperfusion (IR) injury. The aim of this study was to determine the therapeutic efficacy of starting simvastatin after spinal cord IR injury in a rat model. METHODS: In adult Sprague-Dawley rats, spinal cord ischemia was induced using a balloon-tipped catheter placed in the descending thoracic aorta. The animals were then randomly divided into 4 groups: group A (control); group B (0.5 mg/kg simvastatin); group C (1 mg/kg simvastatin); and group D (10 mg/kg simvastatin). Simvastatin was administered orally upon reperfusion for 5 days. Neurological function of the hind limbs was evaluated for 7 days after reperfusion and recorded using a motor deficit score (MDS) (0: normal, 5: complete paraplegia). The number of normal motor neurons within the anterior horns of the spinal cord was counted after final MDS evaluation. Then, the spinal cord was harvested for histopathological examination. RESULTS: Group D showed a significantly lower MDS than the other groups at post-reperfusion day 1 and this trend was sustained throughout the study period. Additionally, a greater number of normal motor neurons was observed in group D than in other groups (group D 21.2 [3.2] vs. group A: 15.8 [4.2]; group B 15.4 [3.4]; and group C 15.5 [3.7]; P = 0.002). CONCLUSIONS: The results of the current study suggest that 10 mg/kg can significantly improve neurologic outcome by attenuating neurologic injury and restoring normal motor neurons after spinal cord IR injury.

Effects of short-term exposure to sevoflurane on the survival, proliferation, apoptosis, and differentiation of neural precursor cells derived from human embryonic stem cells.

PURPOSE: Data from animal experiments suggest that exposure to general anesthetics in early life inhibits neurogenesis and causes long-term memory deficit. Considering short operating times and the popularity of sevoflurane in pediatric anesthesia, it is important to verify the effects of short-period exposure to sevoflurane on the developing brain. METHODS: We measured the effects of short-term exposure (2 h) to 3%, 6%, or 8% sevoflurane, the most commonly used anesthetic, on neural precursor cells derived from human embryonic stem cells, SNUhES32. Cell survival, proliferation, apoptosis, and differentiation on days 1, 3, 5, and 7 post treatment were analyzed. RESULTS: Treatment with 6% sevoflurane increased cell viability (P = 0.046) and decreased apoptosis (P = 0.014) on day 5, but the effect did not persist on day 7. Survival and apoptosis were not affected by 3% and 8% sevoflurane; there was no effect of proliferation at any of the tested concentrations. The differentiation of cells exposed to 6% or 8% sevoflurane decreased on day 1 (P = 0.033 and P = 0.036 for 6% and 8% sevoflurane, respectively) but was again normalized on days 3-7. CONCLUSION: Clinically relevant treatment with sevoflurane for 2 h induces no significant changes in the survival, proliferation, apoptosis, and differentiation of human neural precursor cells, although supraclinical doses of sevoflurane do alter human neurogenesis transiently.

Prospective, randomized, and controlled trial on ketamine infusion during bilateral axillo-breast approach (BABA) robotic or endoscopic thyroidectomy: Effects on postoperative pain and recovery profiles: A consort compliant article.

BACKGROUND: Robotic or endoscopic thyroidectomy using bilateral axillo-breast approach (BABA) is frequently performed for excellent cosmesis. However, postoperative pain is remained as concerns due to the extent tissue dissection and tension during the operation. Ketamine is a noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist that reduces acute postoperative pain. We evaluated the effects of intraoperative ketamine infusion on postoperative pain control and recovery profiles following BABA robotic or endoscopic thyroidectomy. METHODS: Fifty-eight adult patients scheduled for BABA robotic or endoscopic thyroidectomy were randomized into a control group (n = 29) and ketamine group (n = 29). Following induction of anesthesia, patients in each group were infused with the same volume of saline or ketamine solution (1 mg/kg bolus, 60 µg/kg/h continuous infusion). Total intravenous anesthesia with propofol and remifentanil was used to induce and maintain anesthesia. Pain scores (101-point numerical rating scale, 0 = no pain, 100 = the worst imaginable pain), the consumption of rescue analgesics, and other postoperative adverse effects were assessed at 1, 6, 24, and 48 hours postoperatively. RESULTS: Patients in the ketamine group reported lower pain scores than those in the control group at 6 hours (30 [30] vs 50 [30]; P = 0.017), 24 hours (20 [10] vs 30 [20]; P < 0.001), and 48 hours (10 [10] vs 20 [15]; P < 0.001) in neck area. No statistically significant differences were found between the 2 groups in terms of the requirements for rescue analgesics or the occurrence of adverse events. CONCLUSION: Intravenous ketamine infusion during anesthesia resulted in lower postoperative pain scores following BABA robotic or endoscopic thyroidectomy, with no increase in adverse events.

Desflurane increased the activity of excitatory amino-acid carrier 1 (EAAC1) expressed in Xenopus oocytes.

Desflurane is a volatile anaesthetic agent with neuroprotective properties. Excitatory amino-acid carrier 1 (EAAC1) may be neuroprotective by taking up glutamate and cysteine. Therefore, the effects of desflurane on EAAC1 activity were investigated in this study. EAAC1 was expressed in Xenopus laevis oocytes. Two-electrode voltage-clamping technique was used to record membrane currents upon exposure to l-glutamate (30 µM) in the presence or absence of desflurane (0.4, 1.0, 2.0, 2.6, or 3.2mM). Currents were also measured in oocytes pre-exposed to a protein kinase C (PKC) activator (50 nM phorbol-12-myristate-13-acetate, PMA), PKC inhibitors (1 µM staurosporine or 50 µM chelerythrine), or phosphatidylinositol-3-kinase (PI3K) inhibitors (5 µM wortmannin or 10 µM LY294002). Desflurane significantly increased EAAC1 activity. The EC50 of desflurane for increasing the EAAC1 response was 0.75 mM. A kinetic study showed that desflurane significantly increased the Vmax but had no effect on the Km of the EAAC1 response for glutamate. Treatment of oocytes with desflurane plus PMA significantly increased the transporter currents compared to the control, but did not further increase the response compared to either agent alone. Staurosporine attenuated desflurane-enhanced transporter currents without decreasing the basal activity; chelerythrine did not decrease either. In addition, pretreatment of oocytes with two PI3K inhibitors (wortmannin or LY294002) significantly reduced desflurane-enhanced EAAC1 activity without decreasing basal activity. Our results suggest that desflurane increases EAAC1 activity via PKC or PI3K. This enhanced EAAC1 activity may be a mechanism for the neuroprotective effect of desflurane.

Effect of scalp blocks with levobupivacaine on recovery profiles after craniotomy for aneurysm clipping: a randomized, double-blind, and controlled study.

OBJECTIVE: This study was conducted to evaluate the effect of scalp blocks using levobupivacaine on recovery profiles including postoperative pain, patient-controlled analgesia (PCA) consumption, postoperative nausea and vomiting (PONV), and other adverse events in patients undergoing frontoparietal craniotomy for aneurysm clipping. METHODS: Fifty-two patients scheduled for elective frontoparietal craniotomy for unruptured aneurysm clipping were enrolled. After surgery, scalp blocks were performed using normal saline (group C, n = 26) or 0.75% levobupivacaine (group L, n = 26). Postoperative pain scores and PCA consumption were recorded for 72 hours after recovery of consciousness. The time from patient recovery to the first use of PCA drug and rescue analgesics, the requirement for vasoactive agents, and adverse effects related to PCA and local anesthetics also were recorded. RESULTS: Postoperative pain scores and PCA consumption in group L were lower than in group C (P < .05). The time intervals from patient recovery to the first use of PCA drug (P < .001) and rescue analgesics (P = .038) was longer in group L than in group C. Additionally, less antihypertensive agent was required (P = .017), and PONV occurred less frequently (P = .039) in group L than in group C. CONCLUSIONS: Scalp blocks with 0.75% levobupivacaine improved recovery profiles in that it effectively lowered postoperative pain and PCA consumption without severe adverse events and also reduced the requirement for a postoperative antihypertensive agent and the incidence of PONV in patients who underwent frontoparietal craniotomy for aneurysm clipping.

Dexmedetomidine increases the activity of excitatory amino acid transporter type 3 expressed in Xenopus oocytes: the involvement of protein kinase C and phosphatidylinositol 3-kinase.

Dexmedetomidine, an α2 adrenergic agonist, has neuroprotective and anticonvulsant properties in addition to its sedative and anxiolytic effects. We hypothesized that dexmedetomidine would increase the activity of excitatory amino acid transporter type 3 (EAAT3) and that this effect would involve protein kinase C (PKC) and phosphatidylinositol 3-kinase (PI3K), two protein kinases known to regulate EAAT3 activity. EAAT3 was expressed in Xenopus oocytes by injecting its mRNA. Two-electrode voltage clamping was used to record membrane currents before, during, and after application of 30 µM l-glutamate in the presence of 0.1-30 nM dexmedetomidine. Dexmedetomidine-treated oocytes were also exposed to a PKC activator (phorbol-12-myristate-13-acetate [PMA]), PKC inhibitors (chelerythrine, staurosporine, and calphostin C), and PI3K inhibitors (wortmannin and LY294002) before current measurement. Dexmedetomidine application resulted in a concentration-dependent increase in the EAAT3 activity in response to l-glutamate. The kinetic study showed that dexmedetomidine significantly increased the Vmax without changing Km. Treatment of oocytes with PMA significantly increased transporter currents compared with controls, but treatment with dexmedetomidine plus PMA did not further increase the response compared with PMA or dexmedetomidine alone. In addition, pre-treatment of oocytes with PKC inhibitors and PI3K inhibitors significantly abolished the dexmedetomidine-enhanced EAAT3 activity. These results suggest that dexmedetomidine increases the activity of EAAT3 expressed in Xenopus oocytes. PKC and PI3K seem to mediate this effect. These findings may explain the neuroprotective and anticonvulsant effects of dexmedetomidine.

Pretreatment of magnesium sulphate improves intubating conditions of rapid sequence tracheal intubation using alfentanil, propofol, and rocuronium - a randomized trial.

BACKGROUND: We investigated the effects of a magnesium sulfate pretreatment on intubating conditions and cardiovascular responses during rapid sequence tracheal intubation (RSI) in this double-blind randomized study. METHODS: Adult patients (n = 154) were randomly allocated to a rocuronium-0.6, rocuronium-0.9, or magnesium group. The magnesium group was pretreated with 50 mg/kg MgSO4, and the other two groups received the same volume of isotonic saline. Anesthesia was induced with alfentanil, propofol, and either 0.6 mg/kg (rocuronium-0.6 and magnesium groups) or 0.9 mg/kg (rocuronium-0.9 group) rocuronium. An anesthesiologist, blinded to the group assignments, performed RSI and assessed the intubating conditions. Systolic arterial pressure (SAP) and heart rate (HR) were recorded before the magnesium sulfate or normal saline was administered, before anesthesia induction, before intubation, and every minute after intubation for 5 min. RESULTS: Airway features were similar among the three groups. The intubating conditions were improved significantly in the magnesium group (P < 0.001) compared with the other two groups. Significant increases in SAP at 1 min after intubation were observed in the rocuronium-0.6 and -0.9 groups when compared with the magnesium group (P < 0.05). HR was comparable among the three groups (P > 0.05). No hypertensive episode occurred during the immediate post-intubation period in the magnesium group (P = 0.001), and tachycardia occurred most frequently in the rocuronium-0.6 group (P < 0.05). CONCLUSIONS: MgSO4 administered prior to RSI using alfentanil, propofol, and rocuronium may improve intubating conditions and prevent post-intubation hypertension.

Intraoperative plasma lactate as an early indicator of major postoperative events in pediatric cardiac patients.

Hyperlactatemia and unmeasured anions (UMA) have been suggested to be useful predictors of outcomes after pediatric cardiac surgery in the ICU. However, if we detect high-risk patient in the operating room, we could practice early intervention to decrease mortality and morbidity. The purpose of this study was to determine whether the intraoperative lactate or UMA levels can predict adverse outcomes in pediatric cardiac patients with undergoing cardiopulmonary bypass (CPB). We studied 102 patients with congenital heart disease. Arterial blood samples were obtained after inducing anesthesia, 5 min after weaning from CPB and after chest closure. Major adverse events (MAEs) were defined as cardiac compression, re-sternotomy due to hemodynamic instability, extra-corporeal membrane oxygenator support, creatinine levels greater than 2 mg/dL, or death. Patients were divided into MAE group (8 patients, 7.8%) and non-MAE group. Six patients with MAEs died. Importantly, the lactate levels (mmol/L) at weaning from CPB (4.19 vs 2.1; MAE group vs non-MAE group), chest closure (5.76 vs 2.39; MAE group vs non-MAE group) and the intraoperative increases in lactate levels were significantly higher in the MAE group than in the non-MAE group. However, there was no significant difference in the UMA levels or their changes between the groups. The increase in the lactate level from CPB weaning to chest closure was the best predictor of MAEs (AUC: 0.810). In conclusion, the intraoperative plasma lactate levels were more closely associated with MAEs, and they are more useful for predicting the outcome of pediatric cardiac patients than the UMA levels.

The effect of tracheal tube size on air leak around the cuffs.

BACKGROUND: This randomized single-blinded, cross-over study was done to evaluate the influence of the size of tracheal tubes on air leaks around the cuffs. METHODS: In a benchtop model, the number of longitudinal folds on the cuffs was evaluated for different sizes of tracheal tubes. In an anesthetized patient study, thirty patients scheduled for elective surgery under general anesthesia were included. After induction of anesthesia, the trachea was intubated with two sizes of tracheal tubes in a random sequence: in men, internal diameter of 7.5 mm and 8.0 mm; in women, internal diameter of 7.0 mm and 7.5 mm. After tracheal intubation with each tube, air leak pressures were evaluated at intracuff pressures of 20, 25 and 30 cmH(2)O by auscultation. To calculate the tracheal tube resistance (R), an inspiratory pause of 20% was applied and the resulting peak airway pressure (P(peak)), plateau pressure (P(pl)) and mean expiratory tidal volume (Flow) were inserted in the formula R = (P(peak) - P(pl))/Flow. RESULTS: More longitudinal folds of the tracheal tube cuffs occurred in larger sized tubes compared to the smaller ones in a benchtop model. Air leakage was significantly less for the smaller tracheal tubes than for the larger ones for each gender at intracuff pressures of 20, 25 and 30 cmH(2)O. Tracheal tube resistances were not significantly altered by the size of tracheal tube. CONCLUSIONS: The use of a smaller tracheal tube within an acceptable size can reduce air leakage around the cuff without significantly changing the tracheal tube resistance.

Influence of pipe materials and VBNC cells on culturable bacteria in a chlorinated drinking water model system.

To elucidate the influence of pipe materials on the VBNC (viable but nonculturable) state and bacterial numbers in drinking water, biofilm and effluent from stainless steel, galvanized iron, and polyvinyl chloride pipe wafers were analyzed. Although no HPC (heterotrophic plate count) was detected in the chlorinated influent of the model system, a DVC (direct viable count) still existed in the range between 3- and 4-log cells/ml. Significantly high numbers of HPC and DVC were found both in biofilm and in the effluent of the model system. The pipe material, exposure time, and the season were all relevant to the concentrations of VBNC and HPC bacteria detected. These findings indicate the importance of determining the number of VBNC cells and the type of pipe materials to estimate the HPC concentration in water distribution systems and thus the need of determining a DVC in evaluating disinfection efficiency.

Dominance of endospore-forming bacteria on a Rotating Activated Bacillus Contactor biofilm for advanced wastewater treatment.

The bacterial diversity inherent to the biofilm community structure of a modified rotating biological contactor wastewater treatment process, referred to as the Rotating Activated Bacillus Contactor (RABC) process, was characterized in this study, via both culture-dependent and culture-independent methods. On the basis of culture-dependent methods, Bacillus sp. were found to exist in large numbers on the biofilm (6.5% of the heterotrophic bacteria) and the microbial composition of the biofilms was quite simple. Only three phyla were identified-namely, the Proteobacteria, the Actinobacteria (High G+C Gram-positive bacteria), and the Firmicutes (Low G+C Gram-positive bacteria). The culture-independent partial 16S rDNA sequence analysis revealed a considerably more diverse microbial composition within the biofilms. A total of eight phyla were recovered in this case, three of which were major groups: the Firmicutes (43.9%), the Proteobacteria (28.6%), and the Bacteroidetes (17.6%). The remaining five phyla were minor groups: the Planctomycetes (4.4%), the Chlorobi (2.2%), the Actinobacteria (1.1%), the Nitrospirae (1.1%), and the Verrucomicrobia (1.1%). The two most abundant genera detected were the endospore-forming bacteria (31.8%), Clostridium and Bacillus, both of which are members of the Firmicutes phylum. This finding indicates that these endospore-forming bacteria successfully colonized and dominated the RABC process biofilms. Many of the colonies or clones recovered from the biofilms evidenced significantly high homology in the 16S rDNA sequences of bacteria stored in databases associated with advanced wastewater treatment capabilities, including nitrification and denitrification, phosphorus accumulation, the removal of volatile odors, and the removal of chlorohydrocarbons or heavy metals. The microbial community structures observed in the biofilms were found to correlate nicely with the enhanced performance of advanced wastewater treatment protocols.

Dominance of Lysobacter sp. in the rhizosphere of two coastal sand dune plant species, Calystegia soldanella and Elymus mollis.

Bacterial diversity in the rhizosphere of beach morning glory (Calystegia soldanella) and wild rye (Elymus mollis), two of the major plant species inhabiting the coastal sane dune in Tae-An, Korea, was studied by the analysis of community 16S rRNA gene clones. The amplified rDNA restriction analysis (ARDRA) of the clones using HaeIII exhibited significant differences in the community composition between the two plant species as well as regional differences, but also identified a specific ARDRA pattern that was most common among the clones regardless of plant species. Subsequent sequence analysis indicated that the pattern was that of Lysobacter spp., which is a member of the family Xanthomonadaceae, class Gamma proteobacteria. The Lysobacter clones comprised 50.6% of the clones derived from C. soldanella and 62.5% of those from E. mollis. Other minor patterns included those of Pseudomonas spp., species of Rhizobium, Chryseobacterium spp. and Pantoea spp. among C. soldanella clones, and Pseudomonas sp. and Aeromonas hydrophila among E. mollis clones. It is not yet clear what kind of roles Lysobacter plays in association with sand dune plants, but its universal presence in the rhizosphere, together with the potential of this taxon for antagonistic activity against plant pathogens, suggests that Lysobacter might form a symbiotic relationship with its host plants.

Using reagent strips for rapid diagnosis of peritonitis in peritoneal dialysis patients.

Rapid diagnosis of peritonitis remains a significant goal in the management of patients who are maintained on peritoneal dialysis (PD). Several attempts to use leukocyte esterase reagent strips to diagnose peritonitis have been described. In the present study, we evaluated the usefulness of a new reagent strip, the PeriScreen Test Strip (Serim Research, Elkhart, IN, U.S.A.), for diagnosis of peritonitis in PD patients. This reagent strip for leukocyte esterase was designed to test PD fluid. It has 4 colorimetric grades (negative, trace, small, and large). We used the strips to evaluate PD fluid in 54 PD patients. In those patients, we diagnosed 19 episodes of peritonitis as defined by the criteria set out by the International Society for Peritoneal Dialysis. The test strips showed a sensitivity of 100%, a specificity of 97%, a positive predictive value of 95%, and a negative predictive value of 100%. PeriScreen Test Strip reagent strips have excellent utility as a simple, rapid bedside screening test to exclude peritonitis in PD patients.