What are standard monitoring devices for anesthesia in future?

Monitoring the patient's physiological functions is critical in clinical anesthesia. The latest version of the Japanese Society of Anesthesiologists' Guidelines for Safe Anesthesia Monitoring, revised in 2019, covers various factors, including electroencephalogram monitoring, oxygenation, ventilation, circulation, and muscle relaxation. However, with recent advances in monitoring technologies, the information provided has become more detailed, requiring practitioners to update their knowledge. At a symposium organized by the Journal of Anesthesia in 2023, experts across five fields discussed their respective topics: anesthesiologists need to interpret not only the values displayed on processed electroencephalogram monitors but also raw electroencephalogram data in the foreseeable future. In addition to the traditional concern of preventing hypoxemia, monitoring for potential hyperoxemia and the effects of mechanical ventilation itself will become increasingly important. The importance of using AI analytics to predict hypotension, assess nociception, and evaluate microcirculation may increase. With the recent increase in the availability of neuromuscular monitoring devices in Japan, it is important for anesthesiologists to become thoroughly familiar with the features of each device to ensure its effective use. There is a growing desire to develop and introduce a well-organized, integrated "single screen" monitor.

Comparison of the negative effect of remimazolam and propofol on cardiac contractility: Analysis of a randomised parallel-group trial and a preclinical ex vivo study.

Remimazolam is a newly developed ultra-short-acting benzodiazepine that exerts sedative effects. This study aimed to clarify the effects of remimazolam on cardiac contractility. In a randomised-parallel group trial, haemodynamic parameters were compared between propofol (n = 11) and remimazolam (n = 12) groups during the induction of general anaesthesia in patients undergoing non-cardiac surgery. In a preclinical study, the direct effects of remimazolam on cardiac contractility were also evaluated using isolated rat hearts. RNA sequence data obtained from rat and human hearts were analysed to assess the expression patterns of the cardiac γ-aminobutyric acid type A (GABAA ) receptor subunits. In a clinical study, the proportional change of the maximum rate of arterial pressure rise was milder during the study period in the remimazolam group (propofol: -52.6 [10.2] (mean [standard deviation])% vs. remimazolam: -39.7% [10.5%], p = 0.007). In a preclinical study, remimazolam did not exert a negative effect on left ventricle developed pressure, whereas propofol did exert a negative effect after bolus administration of a high dose (propofol: -26.9% [3.5%] vs. remimazolam: -1.1 [6.9%], p < 0.001). Analysis of the RNA sequence revealed a lack of γ subunits, which are part of the major benzodiazepine binding site of the GABAA receptor, in rat and human hearts. These results indicate that remimazolam does not have a direct negative effect on cardiac contractility, which might contribute to its milder effect on cardiac contractility during the induction of general anaesthesia. The expression patterns of cardiac GABAA receptor subunits might be associated with the unique pharmacokinetics of benzodiazepines in the heart.

The First Successful Living Donor Liver Transplantation for Acute-on-Chronic Liver Failure Caused by Severe Acute Necrotizing Pancreatitis: A Case Report.

Liver transplantation (LT) is the only life-saving option when acute-on-chronic liver failure (ACLF) does not improve with conservative therapy. Acute pancreatitis (AP) can cause chronic liver disease progression to ACLF. However, deceased donor LT for patients with AP has had mixed results, and no consensus has been established regarding the indication for LT. We report the first successful living donor LT (LDLT) for ACLF caused by severe AP. The 38-year-old patient with alcoholic liver disease was transferred to our institute with worsening refractory ascites. During the pretransplant workup, she developed severe acute necrotizing pancreatitis, resulting in grade 3 ACLF. The patient's clinical course was further complicated by high levels of donor-specific antibodies and immune thrombocytopenia. The AP gradually improved after intensive care combined with artificial liver support. The patient successfully underwent urgent LDLT with upfront splenectomy and desensitization therapy, including plasm exchange, high-dose intravenous immunoglobulin, and anti-thymocyte globulin. No infection or recurrence of AP was observed postoperatively. We conclude that LDLT is a feasible option for ACLF patients caused by severe AP if a deceased donor is not readily available.

Anesthetic Management of a Cesarean Delivery in a Patient With MYH11 Mutation Who Underwent Aortic Replacement.

We report a case of a pregnant woman with a history of ascending arch replacement for aortic dissection who still had a residual descending aortic dissection. She underwent urgent genetic testing to identify hereditary aortic-related diseases that might be useful in perinatal management. A mutation in the myosin heavy chain gene (MYH11), indicating a high risk of aortic dissection but a low impact on other vascular systems and organs, was identified. Due to concerns about the development of residual aortic dissection, cesarean delivery with combined spinal-epidural anesthesia was selected. Predelivery genetic testing might be useful for perinatal anesthetic management.

Continuous Spinal Anesthesia for Labor Analgesia and Cesarean Delivery in a Parturient With Familial Dilated Cardiomyopathy: A Case Report.

We report a case of successful continuous spinal anesthesia (CSA) for labor analgesia and cesarean delivery in a patient with familial dilated cardiomyopathy (DCM). A 33-year-old pregnant woman diagnosed with DCM was scheduled for a vaginal delivery under labor analgesia. An accidental intrathecal catheter was placed, and labor analgesia was provided by CSA. The vaginal delivery was converted to a cesarean delivery, and an intrathecal catheter was used for transition, which avoided hemodynamic changes and allowed the patient to safely undergo cesarean delivery. CSA is a reliable and rapidly titratable technique that provides excellent analgesia without hemodynamic changes in patients with DCM undergoing labor analgesia and subsequent cesarean delivery.

Bilateral multiple stroke, left upper extremity ischemia, and transient complete atrioventricular block in transcatheter aortic valve implantation: a case report.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) is a minimally invasive surgery. However, there is a risk of surgical manipulation causing detachment of a lesion of the aortic valve, which can result in various embolisms. CASE PRESENTATION: An 87-year-old woman with symptomatic severe aortic valve stenosis was scheduled for transfemoral TAVI under monitored anesthesia. Preoperative examination revealed severe calcification of the aortic valve, but there was no calcification in the ascending aorta. After a delivery catheter system passed the aortic valve, left radial arterial pressure dropped significantly, and complete atrioventricular block (CAVB) occurred. Catecholamine administration and ventricular pacing improved hemodynamics, and a self-expandable valve was implanted. CAVB resolved after surgery, but her state of consciousness was poor, and her left hand became ischemic. Imaging studies revealed multiple embolic infarcts in her bilateral cerebrum and cerebellum. CONCLUSIONS: It should be noted that there is a risk of detachment of a calcified lesion of the aortic valve during TAVI, which can cause embolisms not only in the brain but also in the extremities and coronary arteries.

Apnea management during WATCHMAN device deployment with apneic oxygenation: A case report of three cases.

WATCHMAN is a percutaneous left atrial appendage closure device that is implanted in patients who are unsuitable for anticoagulation therapy for atrial fibrillation. During WATCHMAN implantation, inducing apnea in the patient is preferable to allow stable deployment. We present three cases in which apneic oxygenation was employed to maintain oxygenation during apnea, and oxygen reserve index (ORiTM) was measured to evaluate its safety and efficacy. Oxygen was administered continuously via the endotracheal tube during apnea. During all four apneic events in three patients (mean duration of 356 seconds), the ORi values maintained above 0.24, which is generally considered the threshold of partial pressure of arterial oxygen (PaO2) > 100 mmHg. Transcutaneous oxygen saturation and PaO2 remained above 99% and 300 mmHg, respectively. There were no respiratory or circulatory complications during or after the surgery.

Anesthetic management with remimazolam in very elderly patients undergoing hybrid surgery of transcatheter aortic valve implantation plus off-pump coronary artery bypass grafting: report of two cases.

BACKGROUND: Remimazolam is a short-acting benzodiazepine with small circulatory depression. We used remimazolam for general anesthesia management in two very elderly patients undergoing hybrid surgery of transcatheter aortic valve implantation (TAVI) plus off-pump coronary artery bypass grafting (OPCABG). CASE PRESENTATION: A 96-year-old man (case 1) and a 92-year-old woman (case 2) had complex coronary artery disease (CAD) and severe aortic stenosis (AS) and were scheduled for TAVI plus OPCAB. Anesthesia in both patients was induced with 6 mg/kg/h remimazolam and fentanyl and maintained with 0.3 mg/kg/h and 0.5 mg/kg/h remimazolam and fentanyl, respectively. Although catecholamines were required, we successfully maintained circulation during the induction of anesthesia and the procedures of OPCAB and TAVI. Both patients were discharged without complications. CONCLUSION: Remimazolam can be a useful option for safe general anesthesia in very elderly patients when performing hybrid surgery.

Dexmedetomidine as a cardioprotective drug: a narrative review.

Dexmedetomidine (DEX), a highly selective alpha2-adrenoceptors agonist, is not only a sedative drug used during mechanical ventilation in the intensive care unit but also a cardio-protective drug against ischemia-reperfusion injury (IRI). Numerous preclinical in vivo and ex vivo studies, mostly evaluating the effect of DEX pretreatment in healthy rodents, have shown the efficacy of DEX in protecting the hearts from IRI. However, whether DEX can maintain its cardio-protective effect in hearts with comorbidities such as diabetes has not been fully elucidated. Multiple clinical trials have reported promising results, showing that pretreatment with DEX can attenuate cardiac damage in patients undergoing cardiac surgery. However, evidence of the post-treatment effects of DEX in clinical practice remains limited. In this narrative review, we summarize the previously reported evidence of DEX-induced cardio-protection against IRI and clarify the condition of the hearts and the timing of DEX administration that has not been tested. With further investigations evaluating these knowledge gaps, the use of DEX as a cardio-protective drug could be further facilitated in the management of patients undergoing cardiac surgery and might be considered in a broader area of clinical settings beyond cardiac surgery, including patients with acute myocardial infarction.

Albumin protects the ultrastructure of the endothelial glycocalyx of coronary arteries in myocardial ischemia-reperfusion injury in vivo.

Myocardial ischemia-reperfusion (I/R) injury induces endothelial glycocalyx (GCX) degradation. Several candidate GCX-protective factors including albumin have been identified, few have been demonstrated in in vivo studies and most albumins used to date have been heterologous. Albumin is a carrier protein for sphingosine 1-phosphate (S1P), which has protective effects on the cardiovascular system. However, changes inhibited by albumin in the endothelial GCX structure in I/R in vivo via the S1P receptor has not been reported. In this study, we aimed to determine whether albumin prevents the shedding of endothelial GCX in response to I/R in vivo. Rats were divided into four groups: control (CON), I/R, I/R with albumin preload (I/R + ALB), and I/R + ALB with S1P receptor agonist fingolimod (I/R + ALB + FIN). FIN acts as an initial agonist of S1P receptor 1 and downregulates the receptor in an inhibitory manner. The CON and I/R groups received saline and I/R + ALB and I/R + ALB + FIN groups received albumin solution before left anterior descending coronary artery ligation. Our study used rat albumin. Shedding of endothelial GCX was evaluated in the myocardium by electron microscopy, and the concentration of serum syndecan-1 was measured. Thus, albumin administration maintained the structure of endothelial GCX and prevented shedding of endothelial GCX via the S1P receptor in myocardial I/R, and FIN annihilated the protective effect of albumin against I/R injury.

Anesthesia Management of a Liver Transplant Recipient with Remimazolam.

Background: Intraoperative anesthetic requirements might be altered due to the modulated metabolic function in living donor liver transplant recipients. Remimazolam may provide appropriate anesthesia in patients with cirrhosis. However, the efficacy and safety of remimazolam in liver transplant recipients have not been reported. We present the successful anesthesia management of a liver transplant recipient using remimazolam. Case Presentation. A 54-year-old woman who was diagnosed with Child-Pugh C cirrhosis of unknown etiology was scheduled for living donor liver transplantation. Remimazolam was used for anesthesia management under electroencephalogram monitoring, including bispectral index (BIS) and patient state index (PSI) values. Despite the prolonged surgical time (1,037 min) and massive blood loss (22,500 mL), BIS and PSI values were maintained within acceptable ranges intraoperatively. There was no intraoperative awareness/recall or adverse events associated with remimazolam administered perioperatively. Conclusions: We safely managed general anesthesia for living donor liver transplantation with remimazolam using electroencephalogram monitoring.

Predictors of early postoperative cognitive dysfunction in middle-aged patients undergoing cardiac surgery: retrospective observational study.

PURPOSE: This study aimed to identify the incidence and risk factors of early post-operative cognitive dysfunction (POCD) in middle-aged patients undergoing cardiac surgery. METHODS: Data were examined retrospectively from 71 patients aged 46-64 years who underwent elective cardiac surgery. Magnetic resonance imaging (MRI) and MR angiography were obtained preoperatively to assess prior cerebral infarctions, carotid artery stenosis, and intracranial arterial stenosis. Patients also completed six neuropsychological tests of memory, attention, and executive function before and after surgery. Mild cognitive impairment (MCI) was defined as performance 1.5 standard deviations (SD) below the population means on any neurocognitive battery, whereas POCD was defined as a decrease of 1 SD population means on at least two in the test battery. Patient characteristics were analyzed using univariate analysis, and independent predictors were analyzed using multivariate logistic regression analysis. RESULTS: After surgery, 25 patients (35%) were assessed with POCD. Patients with POCD had significantly higher rates of preoperative MCI and cerebral infarcts on MRI. Multivariate logistic regression analysis identified preoperative MCI and cerebral infarctions detected by MRI as a predictor of POCD. CONCLUSION: More than one-third of middle-aged patients undergoing cardiac surgery developed POCD. Our findings suggested preoperative MCI and infarcts detected by MRI were risk factors for POCD in these middle-aged patients.

Future liver remnant volume is associated with postoperative fentanyl consumption following open donor hepatectomy: a retrospective multivariate analysis.

PURPOSE: Liver resection has a risk of postoperative hepatic dysfunction, including drug metabolism. Since fentanyl is primarily metabolized in the liver, liver resection requires exercising caution against fentanyl overdose in postoperative analgesia. The rationale for dose adjustment of fentanyl in the preoperative prescription for patients undergoing liver resection remains unclear. We examined whether postoperative fentanyl consumption is associated with the future liver remnant after liver resection and investigated factors influencing fentanyl consumption. METHODS: In this retrospective study, 89 living liver donors undergoing open liver resection received intravenous patient-controlled analgesia with fentanyl 2 mg with thoracic epidural analgesia. The primary outcome was postoperative hourly consumption of intravenous patient-controlled analgesia with fentanyl. Future liver remnant volume (ml) and the ratio of future liver remnant volume to whole liver volume (%) were estimated by computed tomography volumetry and compared to determine which correlated more strongly with fentanyl hourly consumption. Multivariable analysis identified independent factors affecting fentanyl consumption, with adjustments for patient characteristics and intravenous patient-controlled analgesia setting. RESULTS: Future liver remnant volume (ml) was significantly correlated more strongly than the ratio of future liver remnant (%) with postoperative fentanyl consumption (r = 0.53 vs. 0.36, p < 0.001). Larger future liver remnant volume (ß = 0.25, p = 0.006) and age < 45 years (ß = 0.24, p = 0.009) were independently associated with higher fentanyl consumption, while sex and weight were not. CONCLUSIONS: Future liver remnant volume was significantly associated with postoperative fentanyl consumption. Smaller remnant liver volume and older age (≥ 45 years) were independent factors reducing postoperative fentanyl consumption in patients undergoing open donor hepatectomy.

Transcatheter aortic valve implantation under lower activated clotting time in a patient with hemorrhagic gastric cancer: a case report.

BACKGROUND: Perioperative management of transcatheter aortic valve implantation (TAVI) in patients with a high risk of bleeding requires careful consideration. CASE PRESENTATION: A 74-year-old man complained of chest pain and was admitted to our hospital. Close examination revealed severe aortic stenosis (AS) and hemorrhagic gastric cancer. Hemorrhage from gastric cancer was controlled using endoscopic hemostasis. While both gastric cancer and AS required surgery, we decided to perform transfemoral transcatheter aortic valve implantation (TAVI) under monitored anesthesia. To reduce bleeding from gastric cancer, we carefully adjusted the heparin dose to maintain the activated clotting time (ACT) between 180 and 200 s. TAVI with a balloon-expandable valve was completed without thrombotic complications. Laparoscopic distal gastrectomy was performed on the 6th day after TAVI. CONCLUSIONS: We report the successful management of TAVI in a patient with hemorrhagic gastric cancer. In TAVI for patients with hemorrhagic diseases, careful consideration of antithrombotic therapy is required.

On the origin and evolution of the asteroid Ryugu: A comprehensive geochemical perspective.

Presented here are the observations and interpretations from a comprehensive analysis of 16 representative particles returned from the C-type asteroid Ryugu by the Hayabusa2 mission. On average Ryugu particles consist of 50% phyllosilicate matrix, 41% porosity and 9% minor phases, including organic matter. The abundances of 70 elements from the particles are in close agreement with those of CI chondrites. Bulk Ryugu particles show higher δ18O, Δ17O, and ε54Cr values than CI chondrites. As such, Ryugu sampled the most primitive and least-thermally processed protosolar nebula reservoirs. Such a finding is consistent with multi-scale H-C-N isotopic compositions that are compatible with an origin for Ryugu organic matter within both the protosolar nebula and the interstellar medium. The analytical data obtained here, suggests that complex soluble organic matter formed during aqueous alteration on the Ryugu progenitor planetesimal (several 10's of km), <2.6 Myr after CAI formation. Subsequently, the Ryugu progenitor planetesimal was fragmented and evolved into the current asteroid Ryugu through sublimation.

Differential effects of remimazolam and propofol on heart rate variability during anesthesia induction.

PURPOSE: The effects of remimazolam on autonomic nervous activity have not been elucidated. We investigated the differential effects of remimazolam and propofol on autonomic nervous activity during anesthesia induction. METHODS: Thirty patients were randomly divided into a remimazolam group or a propofol group for anesthesia induction. Hemodynamics and indices of heart rate variability were recorded before and after anesthesia. Low frequency power (LF; 0.04-0.15 Hz, ms2) and high frequency power (HF; 0.15-0.4 Hz, ms2) were calculated from power spectral density of heart rate variability. LF reflects both sympathetic and parasympathetic activities and HF reflects parasympathetic activity. To investigate the balance between sympathetic and parasympathetic activities, the normalized unit (%) of LF (LF nu) and that of HF (HF nu) were calculated. Changes in LF nu (ΔLF nu) before and after anesthesia (ΔLF nu = LF nu at awake-LF nu after anesthesia) were compared between the groups. RESULTS: Remimazolam and propofol decreased blood pressure and power spectral density of heart rate variability. Remimazolam did not change LF nu and HF nu, while propofol increased LF nu and decreased HF nu (P = 0.020). ΔLF nu in the remimazolam group (1.4 ± 23.6%) were less than that in the propofol group (19.3 ± 22.4%, P = 0.0415). CONCLUSION: Remimazolam and propofol decreased autonomic nervous activity during anesthesia induction. Remimazolam preserved the balance of sympathetic and parasympathetic activities, while propofol modulated it to sympathetic dominance.

Risk factors of cardiac arrest and failure to achieve return of spontaneous circulation during anesthesia: a 20-year retrospective observational study from a tertiary care university hospital.

PURPOSE: There is still a lack of robust data on the epidemiology of cardiac arrest during anesthesia. We investigated the frequency and risk factors of cardiac arrest during anesthesia over the past two decades at a tertiary care university hospital in Japan. METHODS: We retrospectively analyzed 111,851 anesthesia records of patients who underwent surgery under anesthesia between 2000 and 2019. Cardiac arrest cases were classified according to the patient's background, surgical status, main cause and initial rhythm of cardiac arrest, and the presence of the return of spontaneous circulation (ROSC). Univariate and multivariate logistic regression analyses were used to identify the risk factors of cardiac arrest and failure to achieve ROSC. RESULTS: Ninety cardiac arrest cases during anesthesia were identified. The incidence of cardiac arrest was 8.05 per 10,000 anesthetics (95% CI, 6.54-9.90). There were 6 anesthesia-related cardiac arrests and 9 anesthesia-contributory cardiac arrests. The most common cause of cardiac arrest was blood loss. American Society of Anesthesiologists physical status 4-5, emergency surgery, and cardiovascular surgery were identified as independent risk factors of cardiac arrest. American Society of Anesthesiologists physical status 4-5, blood loss-induced cardiac arrest, and non-shockable rhythm were independently associated with failure to achieve ROSC. CONCLUSION: Blood loss was the most common cause of cardiac arrest and blood loss-induced cardiac arrest was independently associated with failure to achieve ROSC. Further improvements in treatment strategies for bleeding may reduce the future incidence of cardiac arrest and death during anesthesia.