Quantitative relationship between anteriorization of alpha oscillations and level of general anesthesia.

A typical electroencephalogram (EEG) change induced by general anesthesia is anteriorization-disappearance of occipital alpha oscillations followed by the development of frontal alpha oscillations. Investigating the quantitative relationship between such a specific EEG change and the level of anesthesia has academic and clinical importance. We quantified the degree of anteriorization and investigated its detailed relationship with the level of anesthesia. We acquired 21-electrode EEG data and bispectral index (BIS) values of 50 patients undergoing surgery from before anesthesia induction until after patient arousal. For each epoch of a 10.24-s window with 1-s offsets, we calculated frontal alpha power [Formula: see text], occipital alpha power [Formula: see text], and their difference [Formula: see text] to quantify anteriorization. We calculated Spearman's rank correlation coefficients between these values and the BIS value. We used locally weighted regression to estimate [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text] at each BIS value. Thirty-six patients (26 females and 10 males aged 24-85 years) were analyzed. The 95% confidence intervals for the mean of Fisher transformations of Spearman's rank correlation coefficients between [Formula: see text], [Formula: see text], and [Formula: see text] and BIS value were [- 0.68, - 0.26], [0.02, 0.62], and [- 1.11, - 0.91], respectively. The change in [Formula: see text] and [Formula: see text] with BIS value showed different patterns by the type of anesthetic agent, whereas that in [Formula: see text] was more consistent with smaller individual variance. Anteriorization, quantified by the difference between frontal and occipital alpha powers, continuously developed in conjunction with general anesthesia. Quantifying anteriorization may provide an objective indicator of the level of anesthesia.

Unexpected deposits in the anesthetic circuit: a possible cause of PEEP/Pmax valve malfunction.

PEEP is regulated by the internal PEEP/maximum peak inspiratory pressure limit (Pmax) valve. Malfunctioning of the PEEP/Pmax valve can result in the creation of unintentional or unstable PEEP, and a reduction of inspired tidal volume. Some of our Dräger Fabius® anesthesia machines were noted to exhibit changes in expiratory waveforms and unstable PEEP during general anesthesia. We considered that the cause was associated with PEEP/Pmax valve malfunction, and then investigated the problems in collaboration with the manufacturer. Seven of the 22 Dräger Fabius® anesthesia workstations at our department exhibited problems with their PEEP/Pmax valves. We replaced the PEEP membrane and sealing washers in these seven anesthesia machines, and the problems were temporarily resolved. After a short interval, however, one of the seven machines began to show a similar phenomenon. We then asked the manufacturer to overhaul the PEEP/Pmax valve and the entire breathing circuit of the machine. On close investigation, we found that the valve components and the internal surface of the breathing circuit were contaminated with unexpected deposits. The build-up of deposits occurred within a year after the previous regular inspection. Our troubleshooting process determined the issue with the PEEP/Pmax valve, which could go unnoticed because the valve is encased inside the breathing circuit, and requires disassembly for close inspection. Our findings should raise awareness regarding the importance of the preventive maintenance cycle as a safety precaution to keep the anesthetic circuit free of unexpected contamination.

Cerebrospinal fluid drainage to prevent postoperative spinal cord injury in thoracic aortic repair.

BACKGROUND: Cerebrospinal fluid drainage (CSFD) is recommended as a spinal cord protective strategy in open and endovascular thoracic aortic repair. Although small studies support the use of CSFD, systematic reviews have not suggested definite conclusion and a large-scale study is needed. Therefore, we reviewed medical records of patients who had undergone descending and thoracoabdominal aortic repair (both open and endovascular repair) at multiple institutions to assess the association between CSFD and postoperative motor deficits. METHODS: Patients included in this study underwent descending or thoracoabdominal aortic repair between 2000 and 2013 at 12 hospitals belonging to the Japanese Association of Spinal Cord Protection in Aortic Surgery. We conducted a retrospective study to investigate whether motor-evoked potential monitoring is effective in reducing motor deficits in thoracic aortic aneurysm repair. We use the same dataset to examine whether CSFD reduces motor deficits after propensity score matching. RESULTS: We reviewed data from 1214 patients [open surgery, 601 (49.5%); endovascular repair, 613 (50.5%)]. CSFD was performed in 417 patients and not performed in the remaining 797 patients. Postoperative motor deficits were observed in 75 (6.2%) patients at discharge. After propensity score matching (n = 700), mixed-effects logistic regression performed revealed that CSFD is associated with postoperative motor deficits at discharge [adjusted odds ratio (OR), 3.87; 95% confidence interval (CI), 2.30-6.51]. CONCLUSION: CSFD may not be effective for postoperative motor deficits at discharge.

A retrospective review of 10-year trends in general anesthesia for cesarean delivery at a university hospital: the impact of a newly launched team on obstetric anesthesia practice.

BACKGROUND: The indications for general anesthesia (GA) in obstetric settings, which are determined in consideration of maternal and fetal outcome, could be affected by local patterns of clinical practice grounded in unique situations and circumstances that vary among medical institutions. Although the use of GA for cesarean delivery has become less common with more frequent adoption of neuraxial anesthesia, GA was previously chosen for pregnancy with placenta previa at our institution in case of unexpected massive hemorrhage. However, the situation has been gradually changing since formation of a team dedicated to obstetric anesthesia practice. Here, we report the results of a review of all cesarean deliveries performed under GA, and assess the impact of our newly launched team on trends in clinical obstetric anesthesia practice at our institution. METHODS: Our original database for obstetric GA during the period of 2010 to 2019 was analyzed. The medical records of all parturients who received GA for cesarean delivery were reviewed to collect detailed information. Interrupted time series analysis was used to evaluate the impact of the launch of our obstetric anesthesia team. RESULTS: As recently as 2014, more than 10% of cesarean deliveries were performed under GA, with placenta previa accounting for the main indication in elective and emergent cases. Our obstetric anesthesia team was formed in 2015 to serve as a communication bridge between the department of anesthesiology and the department of obstetrics. Since then, there has been a steady decline in the percentage of cesarean deliveries performed under GA, decreasing to a low of less than 5% in the latest 2 years. Interrupted time series analysis revealed a significant reduction in obstetric GA after 2015 (P = 0.04), which was associated with decreased use of GA for pregnancy with placenta previa. On the other hand, every year has seen a number of urgent cesarean deliveries requiring GA. CONCLUSIONS: There has been a trend towards fewer obstetric GA since 2015. The optimized use of GA for cesarean delivery was made possible mainly through strengthened partnerships between anesthesiologists and obstetricians with the support of our obstetric anesthesia team.

Prospective evaluation of visual function in patients with ocular diseases after robot-assisted laparoscopic prostatectomy.

OBJECTIVES: To investigate intraocular pressure and visual function in patients with ocular diseases undergoing robot-assisted laparoscopic prostatectomy. METHODS: We carried out a prospective clinical study of patients undergoing robot-assisted laparoscopic prostatectomy for localized prostate cancer at The University of Tokyo Hospital from December 2015 to March 2017. An ophthalmologist measured intraocular pressure, and carried out visual field testing at 0-2 months before and 7 days after robot-assisted laparoscopic prostatectomy. During the surgery, an anesthesiologist measured intraocular pressure at specified time points. RESULTS: A total of 110 patients were enrolled and 98 eligible patients were analyzed; 37 were diagnosed with ocular diseases before robotic-assisted laparoscopic prostatectomy (17 with glaucoma, 20 with other ocular diseases). Intraocular pressure significantly increased during robot-assisted laparoscopic prostatectomy. Transient postoperative visual field defect was detected in 24 eyes of 17 patients, including six patients with ocular diseases at 7 days after surgery. At 3 months after surgery, one of 34 glaucomatous eyes and one of 40 eyes with non-glaucomatous ocular diseases continued to show visual field defect, although visual field defect in the remaining patients recovered to preoperative conditions within 3 months. CONCLUSIONS: Our findings suggest that robot-assisted laparoscopic prostatectomy can be safely carried out in patients with ocular diseases, even those with glaucoma, after precautionary consultation with an ophthalmologist.

Quantitative evaluation of stress in Japanese anesthesiology residents based on heart rate variability and psychological testing.

Clinical anesthesiologists, particularly residents, work in stressful environments. However, evidence-based physiological and psychological tests to evaluate stress are still lacking. In this single-center study of 33 residents, we investigated the relationship between heart rate variability (HRV), which had the potential to screen residents' stress levels using Holter electrocardiography (ECG) and psychological mood as assessed by the Profile of Mood States (POMS) questionnaire. HRV analysis revealed 2 findings. Firstly, standard deviation of the average of 5-min normal-to-normal R-R intervals (SDANN) was significant lower than that of same-aged healthy volunteers (69.3 ± 27.9 vs. 137.0 ± 43.0 ms, P < 0.05), which indicated suppression of autonomic nervous system activity throughout their work. Secondly, at induction of anesthesia, significant higher low frequency/high frequency ratio (LF/HF ratio: 1.326 vs. 0.846; P < 0.05) and lower HF (3326 vs. 5967 ms2; P < 0.05) and lower standard deviation of normal-to-normal R-R intervals (SDNN: 50.5 vs. 79.4 ms; nervous system was suppressed at the induction of anesthesia: expected to be the most stressful period of their work. On the other hand, deviation scores of POMS questionnaire elucidated that all the residents were within normal range of psychological mood, and without any significant diurnal changes with respect to total mood disturbance deviation (TMD) scores (48 vs. 47; P = 0.368). HRV elucidated physiological stress among anesthesiology residents quantitatively by evaluating autonomic nervous activities, especially at induction of anesthesia. These changes in HRV could be observed regardless of psychological mood.

A Novel Technique Using Magnetic Resonance Imaging in the Supine and Prone Positions for Diagnosing Lumbar Adhesive Arachnoiditis: A Preliminary Study.

BACKGROUND: Lumbar adhesive arachnoiditis is a debilitating neuropathic condition and is difficult to diagnose owing to lack of definitive diagnostic criteria. By focusing on the intrathecal mobility of nerve roots, we assessed whether useful diagnostic criteria could be established using MRI. METHODS: Seventeen patients with a high risk for lumbar adhesive arachnoiditis and 18 no-risk patients with chronic low back pain and/or leg pain participated in this study. The patients underwent MRI in both the supine and prone positions. Eleven axial T2-weighted images between the L2 and L5/S levels were obtained, and the proportion of the low-intensity area in the dorsal half to the total low-intensity area in the dural sac was calculated for each axial view. RESULTS: At some lumbar levels, the low-intensity area in the dorsal half of the dural sac was relatively larger in patients with a high risk for lumbar adhesive arachnoiditis than in the no-risk patients. In the no-risk group, the proportion of the low-intensity area in the dorsal half in the supine position was significantly higher than that in the prone position at all lumbar levels. However, in the high-risk group, at some levels, the proportions were not significantly different in the dorsal half of the dural sac between the supine and prone positions. CONCLUSION: In patients with a known risk for lumbar adhesive arachnoiditis, nerve roots lose their potential to migrate in the dural sac in the gravitational force direction on MRI.

Comparison of two point of care whole blood coagulation analysis devices and conventional coagulation tests as a predicting tool of perioperative bleeding in adult cardiac surgery-a pilot prospective observational study in Japan.

BACKGROUND: It is widely accepted that Point-of Care Test (PoCT) devices are useful in the detection of coagulopathies in situations of massive bleeding such as major cardiac surgery. These devices contribute to the reduction of blood transfusion. However, their implementation remains limited in Japan because of their cost and lack of health insurance support. STUDY DESIGN AND METHODS: Conventional coagulation tests and thromboelastography (TEG)/Sonoclot values were measured in 50 consecutive cardiac surgery cases. Clinical background information such as operative procedures was obtained from electronic medical records, and the theoretical perioperative total blood loss was calculated by measuring the hemoglobin content and total red blood cell transfusion volume. The correlation between perioperative total blood loss and the measured laboratory values or clinical parameters was evaluated by a multivariate linear regression analysis. The risk factors of the total amount of platelet transfusion and postoperative drain bleeding volume were similarly evaluated. RESULTS: No significant association between the estimated perioperative total blood loss (eTBL) and the laboratory measurements including conventional coagulation tests, TEG and Sonoclot was observed. On the other hand, postoperative drain bleeding volume was significantly associated with postoperative Sonoclot CR (p = 0.039) as well as preoperative use of oral anticoagulants and cell saver treated blood volume. Platelet transfusion amount was significantly associated with post-CBP PF and time to peak value of Sonoclot (p = 0.014 and 0.001, respectively). CONCLUSION: Sonoclot measurements may be useful to estimate the risks of postoperative bleeding and platelet transfusion in cardiac surgeries in Japan.

Resistin Is a Novel Marker for Postoperative Pain Intensity.

BACKGROUND: Pro- and anti-inflammatory cytokines (adipokines) associated with adipose tissue can modulate inflammatory processes and lead to systemic inflammatory conditions such as metabolic syndrome. In the present pilot study, we investigated 3 major adipokines (leptin, adiponectin, and resistin) and 2 nonspecific proinflammatory cytokines (tumor necrosis factor α and interleukin-6) with regard to their association with postoperative pain intensity. METHODS: We analyzed a total of 45 single-nucleotide polymorphisms of the adipokines in 57 patients with postlaparotomy pain. We adjusted for multiple testing to reduce the chance of false-positive results by controlling the false discovery rate. Serum levels of the adipokines and proinflammatory cytokines were measured in another 36 patients undergoing laparotomy. A stepwise multiple linear regression analysis using these measurements and opioid dosages as independent variables was performed to explore the factors associated with postoperative pain. RESULTS: Only 1 variant of the resistin gene (rs3745367) demonstrated a significant association with postoperative pain (P < .002). Patients exhibiting homozygosity for the minor alleles (n = 7; numerical rating scale [NRS], 2.3 ± 1.3) demonstrated lower pain intensity compared with those exhibiting homozygosity for the major alleles (n = 29; NRS, 3.8 ± 1.0; P = .004) and heterozygosity for the minor alleles (n = 21; NRS, 4.2 ± 0.8; P < .001). Only serum resistin levels showed a positive association with postoperative pain. CONCLUSIONS: A genetic variant of resistin and serum resistin levels were associated with postoperative pain intensity, while other adipokines and cytokines exhibit no such association. Resistin can alter the inflammatory responses in postoperative wounds, although it could be a determinant factor that is independent of inflammatory processes. Resistin may be a novel marker for postoperative pain intensity.

Reference value for expiratory time constant calculated from the maximal expiratory flow-volume curve.

BACKGROUND: The expiratory time constant (RCEXP), which is defined as the product of airway resistance and lung compliance, enable us to assess the mechanical properties of the respiratory system in mechanically ventilated patients. Although RCEXP could also be applied to spontaneously breathing patients, little is known about RCEXP calculated from the maximal expiratory flow-volume (MEFV) curve. The aim of our study was to determine the reference value for RCEXP, as well as to investigate the association between RCEXP and other respiratory function parameters, including the forced expiratory volume in 1 s (FEV1)/ forced vital capacity (FVC) ratio, maximal mid-expiratory flow rate (MMF), maximal expiratory flow at 50 and 25% of FVC (MEF50 and MEF25, respectively), ratio of MEF50 to MEF25 (MEF50/MEF25). METHODS: Spirometric parameters were extracted from the records of patients aged 15 years or older who underwent pulmonary function testing as a routine preoperative examination before non-cardiac surgery at the University of Tokyo Hospital. RCEXP was calculated in each patient from the slope of the descending limb of the MEFV curve using two points corresponding to MEF50 and MEF25. Airway obstruction was defined as an FEV1/FVC and FEV1 below the statistically lower limit of normal. RESULTS: We retrospectively analyzed 777 spirometry records, and 62 patients were deemed to have airway obstruction according to Japanese spirometric reference values. The cut-off value for RCEXP was 0.601 s with an area under the receiver operating characteristic curve of 0.934 (95% confidence interval = 0.898-0.970). RCEXP was strongly associated with FEV1/FVC, and was moderately associated with MMF and MEF50. However, RCEXP was less associated with MEF25 and MEF50/MEF25. CONCLUSIONS: Our findings suggest that an RCEXP of longer than approximately 0.6 s can be linked to the presence of airway obstruction. Application of the concept of RCEXP to spontaneously breathing subjects was feasible, using our simple calculation method.

Association Between Motor-Evoked Potentials and Spinal Cord Damage Diagnosed With Magnetic Resonance Imaging After Thoracoabdominal and Descending Aortic Aneurysm Repair.

OBJECTIVES: The authors investigated the association between intraoperative motor-evoked potential (MEP) changes and the severity of spinal cord infarction diagnosed with magnetic resonance imaging (MRI) to clarify the discrepancy between them, which was observed in patients with postoperative motor deficits after thoracic and thoracoabdominal aortic surgery. DESIGN: A multicenter retrospective study. SETTING: Motor-evoked potential <25% of control values was deemed positive for spinal cord ischemia. The severity of spinal cord infarction was categorized into grades A to D based on previous studies using the most severe axial MRI slices. The associations between MRI grade, MEP changes, and motor deficits were examined using logistic regression. PARTICIPANTS: Twenty-three of 1,245 patients (from 1999 to 2013, at 12 hospitals in Japan) were extracted from medical records of patients who underwent thoracic and thoracoabdominal aortic repair, with intraoperative MEP examinations and postoperative spinal MRI. INTERVENTIONS: No intervention (observational study). MEASUREMENTS AND MAIN RESULTS: Motor-evoked potential <25% of control value was associated significantly with motor deficits at discharge (adjusted odds ratio [OR], 130.0; p = 0.041), but not with severity of spinal cord infarction (adjusted OR, 0.917; p = 0.931). Motor deficit at discharge was associated with severe spinal cord infarction (adjusted OR, 4.83; p = 0.043), MEP <25% (adjusted OR, 13.95; p = 0.031), and combined deficits (motor and sensory, motor and bowel or bladder, or sensory and bowel or bladder deficits; adjusted OR, 31.03; p = 0.072) in stepwise logistic regression analysis. CONCLUSION: Motor-evoked potential <25% was associated significantly with motor deficits at discharge, but not with the severity of spinal cord infarction.

IFN-ß Improves Sepsis-related Alveolar Macrophage Dysfunction and Postseptic Acute Respiratory Distress Syndrome-related Mortality.

IFN-ß is reported to improve survival in patients with acute respiratory distress syndrome (ARDS), possibly by preventing sepsis-induced immunosuppression, but its therapeutic nature in ARDS pathogenesis is poorly understood. We investigated the therapeutic effects of IFN-ß for postseptic ARDS to better understand its pathogenesis in mice. Postseptic ARDS was reproduced in mice by cecal ligation and puncture to induce sepsis, followed 4 days later by intratracheal instillation of Pseudomonas aeruginosa to cause pneumonia with or without subcutaneous administration of IFN-ß 1 day earlier. Sepsis induced prolonged increases in alveolar TNF-α and IL-10 concentrations and innate immune reprogramming; specifically, it reduced alveolar macrophage (AM) phagocytosis and KC (CXCL1) secretion. Ex vivo AM exposure to TNF-α or IL-10 duplicated cytokine release impairment. Compared with sepsis or pneumonia alone, pneumonia after sepsis was associated with blunted alveolar KC responses and reduced neutrophil recruitment into alveoli despite increased neutrophil burden in lungs (i.e., "incomplete alveolar neutrophil recruitment"), reduced bacterial clearance, increased lung injury, and markedly increased mortality. Importantly, IFN-ß reversed the TNF-α/IL-10-mediated impairment of AM cytokine secretion in vitro, restored alveolar innate immune responsiveness in vivo, improved alveolar neutrophil recruitment and bacterial clearance, and consequently reduced the odds ratio for 7-day mortality by 85% (odds ratio, 0.15; 95% confidence interval, 0.03-0.82; P = 0.045). This mouse model of sequential sepsis → pneumonia infection revealed incomplete alveolar neutrophil recruitment as a novel pathogenic mechanism for postseptic ARDS, and systemic IFN-ß improved survival by restoring the impaired function of AMs, mainly by recruiting neutrophils to alveoli.

Early-phase Innate Immune Suppression in Murine Severe Sepsis Is Restored with Systemic Interferon-ß.

BACKGROUND: Sepsis is a leading cause of death in the intensive care unit. Immune modulatory therapy targeting sepsis-associated proinflammatory responses has not shown survival benefit. Here, the authors evaluated innate immunity at the early stage of murine mild or severe peritoneal sepsis induced by cecal ligation and puncture, and the effect of systemic interferon-ß, a potent inflammatory mediator, on severe sepsis as well as its mechanism of action. METHODS: Mild and severe sepsis was induced in C57BL/6 mice by cecal ligation and puncture with 22- and 18-gauge needles for puncture, respectively. Interferon-ß (700 U/g) was subcutaneously administered either before or 12 h after cecal ligation and puncture for the severe sepsis group. RESULTS: Severe sepsis resulted in significantly lower 6-day survival rates than mild sepsis (n = 48, 25% vs. n = 11, 81.8%, P = 0.002), significantly less phagocytic capacity of peritoneal exudate cells, and lower CXC chemokine receptor-2 expression on circulating neutrophils at 24 h after cecal ligation and puncture. Interferon-ß administration 12 h after cecal ligation and puncture associated with significantly improved survival (n = 34, 52.9%, P = 0.017) increased the number and function of peritoneal exudate cells, peritoneal/systemic inflammatory cytokine/chemokine concentrations, and CXC chemokine receptor-2 on neutrophils, compared with the severe sepsis controls. However, those responses were not observed in the prophylactic interferon-ß group (n = 24). Interferon-ß increased lipopolysaccharide-induced interleukin-6 messenger RNA/protein expression of lipopolysaccharide-tolerant murine peritoneal macrophages, which was not observed in nontolerant cells. CONCLUSIONS: In severe sepsis, immune suppression occurs within 24 h and is associated with worse mortality. Interferon-ß given after the onset of peritonitis restores impaired innate immunity in vivo and in vitro.

Association Between Polymorphisms in the Purinergic P2Y12 Receptor Gene and Severity of Both Cancer Pain and Postoperative Pain.

Background: Despite the widespread use of opioids for the treatment of cancer pain, results from several surveys consistently show that pain is still prevalent in some patients with malignant diseases. The purinergic P2Y12 receptor is a primary site leading to microglial activation and hyperalgesic pain behaviors and is considered a key regulator in the prevention of the aggravation of clinical pain conditions. Genetic variability in the P2RY12 gene may contribute to individual differences in pain and opioid sensitivity. Methods: We genotyped 31 single nucleotide polymorphisms (SNPs) throughout the P2RY12 gene and compared genotypes against pain measurements and opioid requirements in Japanese cancer pain patients (N = 90). The most promising SNP association with pain severity was validated by genotyping an additional postoperative pain patient cohort (N = 355). Results: Five SNPs (rs3732765, rs9859538, rs17283010, rs11713504, and rs10935840) of the P2RY12 gene were significantly associated with cancer pain severity, although opioid requirements were comparable in each genotype of the five SNPs. The alleles of these SNPs represented one absolute linkage disequilibrium block of the P2RY12 gene. In the second association study of postoperative pain, subjects carrying the minor T allele of the rs3732765 SNP demonstrated more intense 24-hour postoperative pain compared with subjects not carrying this allele although total 24-hour postoperative opioid consumptions based on weight were comparable. Conclusions: Polymorphisms of the P2RY12 gene may predict individual differences in both cancer and postoperative pain severity; this might be caused by functional alteration of nociceptive neurons through neuron-glia interaction.

Clinical Utility of Intraoperative Motor-Evoked Potential Monitoring to Prevent Postoperative Spinal Cord Injury in Thoracic and Thoracoabdominal Aneurysm Repair: An Audit of the Japanese Association of Spinal Cord Protection in Aortic Surgery Database.

BACKGROUND: Spinal cord ischemic injury is the most devastating sequela of descending and thoracoabdominal aortic surgery. Motor-evoked potentials (MEPs) have been used to intraoperatively assess motor tract function, but it remains unclear whether MEP monitoring can decrease the incidence of postoperative motor deficits. Therefore, we reviewed multicenter medical records of patients who had undergone descending and thoracoabdominal aortic repair (both open surgery and endovascular repair) to assess the association of MEP monitoring with postoperative motor deficits. METHODS: Patients included in the study underwent descending or thoracoabdominal aortic repair at 12 hospitals belonging to the Japanese Association of Spinal Cord Protection in Aortic Surgery between 2000 and 2013. Using multivariable mixed-effects logistic regression analysis, we investigated whether intraoperative MEP monitoring was associated with postoperative motor deficits at discharge after open and endovascular aortic repair. RESULTS: We reviewed data from 1214 patients (open surgery, 601 [49.5%]; endovascular repair, 613 [50.5%]). MEP monitoring was performed in 631 patients and not performed in the remaining 583 patients. Postoperative motor deficits were observed in 75 (6.2%) patients at discharge. Multivariable logistic regression analysis revealed that postoperative motor deficits at discharge did not have a significant association with MEP monitoring (adjusted odds ratio [OR], 1.13; 95% confidence interval [CI], 0.69-1.88; P = .624), but with other factors: history of neural deficits (adjusted OR, 6.08; 95% CI, 3.10-11.91; P < .001), spinal drainage (adjusted OR, 2.14; 95% CI, 1.32-3.47; P = .002), and endovascular procedure (adjusted OR, 0.45; 95% CI, 0.27-0.76; P = .003). The sensitivity and specificity of MEP <25% of control value for motor deficits at discharge were 37.8% (95% CI, 26.5%-49.5%) and 95.5% (95% CI, 94.7%-96.4%), respectively. CONCLUSIONS: MEP monitoring was not significantly associated with motor deficits at discharge.

MicroRNA-31 is a positive modulator of endothelial-mesenchymal transition and associated secretory phenotype induced by TGF-ß.

Transforming growth factor-ß (TGF-ß) plays central roles in endothelial-mesenchymal transition (EndMT) involved in development and pathogenesis. Although EndMT and epithelial-mesenchymal transition are similar processes, roles of microRNAs in EndMT are largely unknown. Here, we report that constitutively active microRNA-31 (miR-31) is a positive regulator of TGF-ß-induced EndMT. Although the expression is not induced by TGF-ß, miR-31 is required for induction of mesenchymal genes including α-SMA, actin reorganization and MRTF-A activation during EndMT. We identified VAV3, a regulator of actin remodeling and MRTF-A activity, as a miR-31 target. Global transcriptome analysis further showed that miR-31 positively regulates EndMT-associated unique secretory phenotype (EndMT-SP) characterized by induction of multiple inflammatory chemokines and cytokines including CCL17, CX3CL1, CXCL16, IL-6 and Angptl2. As a mechanism for this phenomenon, TGF-ß and miR-31 suppress Stk40, a negative regulator of NF-κB pathway. Interestingly, TGF-ß induces alternative polyadenylation (APA)-coupled miR-31-dependent Stk40 suppression without concomitant miR-31 induction, and APA-mediated exclusion of internal poly(A) sequence in Stk40 3'UTR enhances target efficiency of Stk40. Finally, miR-31 functions as a molecular hub to integrate TGF-ß and TNF-α signaling to enhance EndMT. These data confirm that constitutively active microRNAs, as well as inducible microRNAs, serve as phenotypic modifiers interconnected with transcriptome dynamics during EndMT.

Impact of Epinephrine Contained in Local Anesthetic Solution on Serum Lactate Level During Orthognathic Surgery.

PURPOSE: There have been many discussions of a relation between endogenous and exogenous epinephrine and hyperlactatemia. This study aimed to identify the impact of epinephrine contained in a local anesthetic solution on serum lactate levels in patients who underwent orthognathic surgery. MATERIALS AND METHODS: This study was a retrospective record review of cases of maxillary and mandibular osteotomy at the Tokyo University Hospital (Tokyo, Japan) from January 2006 through December 2014. One hundred ninety-three patients were enrolled in this study. RESULTS: The maximum intraoperative serum lactate level was 22.3 ± 14.7 mg/dL. Of 193 patients, 91 showed an intraoperative serum lactate level that was higher than the normal maximum of 19.8 mg/dL (2.2 mmol/L), and 16 of these had a level that was at least 40 mg/dL (≥4.49 mmol/L). Multiple logistic regression analysis showed 2 factors that could increase the serum lactate level: the amount of epinephrine contained in the local anesthetic solution injected into the oral cavity (odds ratio [OR] = 1.014; 95% confidence interval [CI], 1.006-1.022; P = .0001) and the absence of intraoperative treatment with propranolol (OR, 0.105; 95% CI, 0.019-0.434; P = .0013). Patients with severe serum lactate concentrations (ie, ≥40 mg/dL [≥4.49 mmol/L]) had slight metabolic acidosis. All patients survived 90 days. The number of postoperative hospitalization days for patients with severe serum lactate concentrations was 12.8 ± 2.6 days and that for patients without severe serum lactate concentration was 16.0 ± 8.6 days. CONCLUSION: Increases in intraoperative serum lactate levels during orthognathic surgery are associated, at least in part, with increased aerobic glycolysis because of ß2-adrenergic signaling. Lactate increase caused by epinephrine contained in a local anesthetic solution does not result in a poor postoperative outcome.

Reliability of cardiac output measurements using LiDCOrapid™ and FloTrac/Vigileo™ across broad ranges of cardiac output values.

Knowing a patient's cardiac output (CO) could contribute to a safe, optimized hemodynamic control during surgery. Precise CO measurements can serve as a guide for resuscitation therapy, catecholamine use, differential diagnosis, and intervention during a hemodynamic crisis. Despite its invasiveness and intermittent nature, the thermodilution technique via a pulmonary artery catheter (PAC) remains the clinical gold standard for CO measurements. LiDCOrapid™ (LiDCO, London, UK) and FloTrac/Vigileo™ (Edwards Lifesciences, Irvine, CA) are less invasive continuous CO monitors that use arterial waveform analysis. Their calculations are based on arterial waveform characteristics and do not require calibration. Here, we evaluated LiDCOrapid™ and FloTrac/Vigileo™ during off-pump coronary artery bypass graft (OPCAB) and living-donor liver transplantation (LDLT) surgery. This observational, single-center study included 21 patients (11 OPCAB and 10 LDLT). We performed simultaneous measurements of CO at fixed sampling points during surgery using both devices (LiDCOrapid™ version 1.04-b222 and FloTrac/Vigileo™ version 3.02). The thermodilution technique via a PAC was used to obtain the benchmark data. LiDCOrapid™ and FloTrac/Vigileo™ were used in an uncalibrated fashion. We analyzed the measured cardiac index using a Bland-Altman analysis (the method of variance estimates recovery), a polar plot method (half-moon method), a 4-quadrant plot and compared the widths of the limits of agreement (LOA) using an F test. One OPCAB patient was excluded because of the use of an intra-aortic balloon pumping during surgery, and 20 patients (10 OPCAB and 10 LDLT) were ultimately analyzed. We obtained 149 triplet measurements with a wide range of cardiac index. For the FloTrac/Vigileo™, the bias and percentage error were -0.44 L/min/m2 and 74.4 %. For the LiDCOrapid™, the bias and percentage error were -0.38 L/min/m2 and 53.5 %. The polar plot method showed an angular bias (FloTrac/Vigileo™ vs. LiDCOrapid™: 6.6° vs. 5.8°, respectively) and radial limits of agreement (-63.9 to 77.1 vs. -41.6 to 53.1). A 4-quadrant plot was used to obtain concordance rates (FloTrac/Vigileo™ vs. PAC and LiDCOrapid™ vs. PAC: 84.0 and 92.4 %, respectively). We could compare CO measurement devices across broad ranges of CO and SVR using LDLT and OPCAB surgical patients. An F test revealed no significant difference in the widths of the LoA for both devices when sample sizes capable of detecting a more than two-fold difference were used. We found that both devices tended to underestimate the calculated CIs when the CIs were relatively high. These proportional bias produced large percentage errors in the present study.

Perioperative Point-of-care Ultrasonography: Preface and Comments.

Recent years have witnessed remarkable progress in the medical equipment including ultrasound devices. There has also been an increasing interest in point-of-care ultrasound in the field of perioperative medicine. This editorial outlines the basis of point-of-care ultrasound to aid anesthesiologists, focusing on how to make better use of this useful tool.