Effects of volatile anesthetics on circadian rhythm in mice: a comparative study of sevoflurane, desflurane, and isoflurane.

PURPOSE: Volatile anesthetics affect the circadian rhythm of mammals, although the effects of different types of anesthetics are unclear. Here, we anesthetized mice using several volatile anesthetics at two different times during the day. Our objective was to compare the effects of these anesthetics on circadian rhythm. METHODS: Male adult C57BL/6 J mice were divided into eight groups (n = 8 each) based on the anesthetic (sevoflurane, desflurane, isoflurane, or no anesthesia) and anesthesia time (Zeitgeber time [ZT] 6-12 or ZT18-24). Mice were anesthetized for 6 h using a 0.5 minimum alveolar concentration (MAC) dose under constant dark conditions. The difference between the start of the active phase before and after anesthesia was measured as a phase shift. Clock genes were measured by polymerase chain reaction in suprachiasmatic nucleus (SCN) samples removed from mouse brain after anesthesia (n = 8-9 each). RESULTS: Phase shift after anesthesia at ZT6-12 using sevoflurane (- 0.49 h) was smaller compared with desflurane (- 1.1 h) and isoflurane (- 1.4 h) (p < 0.05). Clock mRNA (ZT6-12, p < 0.05) and Per2 mRNA (ZT18-24, p < 0.05) expression were different between the groups after anesthesia. CONCLUSION: 0.5 MAC sevoflurane anesthesia administered during the late inactive to early active phase has less impact on the phase shift of circadian rhythm than desflurane and isoflurane. This may be due to differences in the effects of volatile anesthetics on the expression of clock genes in the SCN, the master clock of the circadian rhythm.

Electrocardiogram Cream Reduces Skin-Electrode Impedance Upon Neuromuscular Monitoring Using TOF-Cuff®.

Background Mechanistic insight into the high failure rate of TOF-Cuff® (RGB Medical Devices, Madrid, Spain) measurements on the lower leg is unclear. Aims We aimed to determine whether materials applied to pseudo-skin can reduce the impedance between a model arm and TOF-Cuff® electrodes and whether a material between TOF-Cuff® electrodes and the patient's skin surface decreases the skin-TOF-Cuff® electrode impedance within the appropriate range. Methods This was a combination of an in vitro study using non-living materials and a prospective observational clinical study. Eight patients aged > 70 years who had undergone elective surgery were eligible. One of the primary outcomes was whether water, electrocardiogram (ECG) cream, or ECG gel applied on the pseudo-skin could reduce the impedance between the model arm and the TOF-Cuff® electrodes in the in vitro study. Another was whether a material between the TOF-Cuff® electrodes and the patient's skin surface decreased the skin-TOF-Cuff® electrode impedance to an appropriate level of less than 5,000 Ω in the clinical study. Results The application of water, ECG cream, and ECG gel similarly reduced the impedance values within the electrical circuit in the in vitro study. ECG cream application between the patient's skin surface and the TOF-Cuff® electrodes decreased the skin-TOF-Cuff® electrode impedance (median (interquartile range (IQR)) Ω) from 8,600 (6,450 to 9,775) to 2,000 (1,600 to 2,600) (P = 0.012) in surgical patients. Conclusion ECG cream application between the patient's skin surface and the TOF-Cuff® electrodes decreased the skin-TOF-Cuff® electrode impedance appropriately, and thus, the application can facilitate precise TOF-Cuff® measurements in patients.

Dietary Iron Restriction Protects Against Aneurysm Rupture in a Mouse Model of Intracranial Aneurysm.

INTRODUCTION: Iron accumulation in vessel walls induces oxidative stress and inflammation, which can cause cerebrovascular damage, vascular wall degeneration, and intracranial aneurysmal formation, growth, and rupture. Subarachnoid hemorrhage from intracranial aneurysm rupture results in significant morbidity and mortality. This study used a mouse model of intracranial aneurysm to evaluate the effect of dietary iron restriction on aneurysm formation and rupture. METHODS: Intracranial aneurysms were induced using deoxycorticosterone acetate-salt-induced hypertension and a single injection of elastase into the cerebrospinal fluid of the basal cistern. Mice were fed an iron-restricted diet (n = 23) or a normal diet (n = 25). Aneurysm rupture was detected by neurological symptoms, while the presence of intracranial aneurysm with subarachnoid hemorrhage was confirmed by post-mortem examination. RESULTS: The aneurysmal rupture rate was significantly lower in iron-restricted diet mice (37%) compared with normal diet mice (76%; p < 0.05). Serum oxidative stress, iron accumulation, macrophage infiltration, and 8-hydroxy-2'-deoxyguanosine in the vascular wall were lower in iron-restricted diet mice (p < 0.01). The areas of iron positivity were similar to the areas of CD68 positivity and 8-hydroxy-2'-deoxyguanosine in both normal diet and iron-restricted diet mice aneurysms. CONCLUSIONS: These findings suggest that iron is involved intracranial aneurysm rupture via vascular inflammation and oxidative stress. Dietary iron restriction may have a promising role in preventing intracranial aneurysm rupture.

Postoperative norepinephrine versus dopamine in patients undergoing noncardiac surgery: a propensity-matched analysis using a nationwide intensive care database.

BACKGROUND: Choosing catecholamines, such as norepinephrine and dopamine, for perioperative blood pressure control is essential for anesthesiologists and intensivists. However, studies specific to noncardiac surgery are limited. Therefore, we aimed to evaluate the effects of postoperative norepinephrine and dopamine on clinical outcomes in adult noncardiac surgery patients by analyzing a nationwide intensive care patient database. METHODS: The Japanese Intensive care PAtient Database (JIPAD) was used for this multicenter retrospective study. Adult patients in the JIPAD who received norepinephrine or dopamine within 24 h after noncardiac surgery in 2018-2020 were included. We compared the norepinephrine and dopamine groups using a one-to-one propensity score matching analysis. The primary outcome was in-hospital mortality. Secondary outcomes were intensive care unit (ICU) mortality, hospital length of stay, and ICU length of stay. RESULTS: A total of 6,236 eligible patients from 69 ICUs were allocated to the norepinephrine (n = 4,652) or dopamine (n = 1,584) group. Propensity score matching was used to create a matched cohort of 1,230 pairs. No differences in the in-hospital mortality was found between the two propensity score matched groups (risk difference: 0.41%, 95% CI [-1.15, 1.96], P = 0.608). Among the secondary outcomes, only the ICU length of stay was significantly shorter in the norepinephrine group than in the dopamine group (median length: 3 vs. 4 days, respectively; P < 0.001). CONCLUSIONS: In adult patients after noncardiac surgery, norepinephrine was not associated with decreased mortality but was associated with a shorter ICU length of stay than dopamine.

Development of Low-Molecular-Weight Organogelators from Cyclic ß-Amino Acid: Effect of Stereochemistry and their Application on Visual Chiral Recognition of Amines.

This study reports the formation of low-molecular-weight gelators based on carboxylic acids derived from chiral cyclicß-amino acids. The effect of their stereochemistry on the gelation of organic solvents was investigated, and their assemblies with the intermolecular interactions in the xerogels were proposed via infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and crystallographic details of the related model compounds. The effect of the alkyl chain length on the gelators was studied, and they were applied to the chiral recognition of amines. Only one diastereomeric salt with amines afforded gels, whereas the others resulted in precipitates. Chiral recognition was also achieved in the gel state, and the appearance of the as-prepared gel changed upon the addition of each amine enantiomer, thus enabling the visual detection of their chirality.

Treatment-resistant venous thrombosis and pulmonary embolism in a patient with granulomatosis with polyangiitis: a case report.

BACKGROUND: We herein present a case of venous thrombosis that developed more than 20 years after diagnosis of granulomatosis with polyangiitis (GPA), although many reports of GPA have described venous thrombosis within 1 year of diagnosis. CASE PRESENTATION: A 73-year-old man with GPA was admitted for lower extremity swelling and diagnosed with venous thrombosis and pulmonary embolism. On the second day, catheter-based thrombolysis was unsuccessful, and inferior vena cava filter insertion and anticoagulation were performed. On the third day, respiratory disturbance and loss of consciousness appeared and progressed. The patient died on the fifth day. The autopsy revealed a large thrombus in the inferior vena cava filter, and death of progressive venous thrombosis was suspected. CONCLUSIONS: We experienced a case of venous thrombosis that developed 20 years after diagnosis of GPA, although GPA is frequently associated with venous thrombosis immediately after diagnosis. The thrombosis progressed rapidly and was resistant to treatment.