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.

Hydrogen attenuates endothelial glycocalyx damage associated with partial cardiopulmonary bypass in rats

Cardiopulmonary bypass (CPB) causes systemic inflammation and endothelial glycocalyx damage. Hydrogen has anti-oxidant and anti-inflammatory properties; therefore, we hypothesized that hydrogen would alleviate endothelial glycocalyx damage caused by CPB. Twenty-eight male Sprague-Dawley rats were randomly divided into four groups (n = 7 per group), as follows: sham, control, 2% hydrogen, and 4% hydrogen. The rats were subjected to 90 minutes of partial CPB followed by 120 minutes of observation. In the hydrogen groups, hydrogen was administered via the ventilator and artificial lung during CPB, and via the ventilator for 60 minutes after CPB. After observation, blood collection, lung extraction, and perfusion fixation were performed, and the heart, lung, and brain endothelial glycocalyx thickness was measured by electron microscopy. The serum syndecan-1 concentration, a glycocalyx component, in the 4% hydrogen group (5.7 ± 4.4 pg/mL) was lower than in the control (19.5 ± 6.6 pg/mL) and 2% hydrogen (19.8 ± 5.0 pg/mL) groups (P < 0.001 for each), but it was not significantly different from the sham group (6.2 ± 4.0 pg/mL, P = 0.999). The endothelial glycocalyces of the heart and lung in the 4% hydrogen group were thicker than in the control group. The 4% hydrogen group had lower inflammatory cytokine concentrations (interleukin-1β and tumor necrosis factor-α) in serum and lung tissue, as well as a lower serum malondialdehyde concentration, than the control group. The 2% hydrogen group showed no significant difference in the serum syndecan-1 concentration compared with the control group. However, non-significant decreases in serum and lung tissue inflammatory cytokine concentrations, as well as in serum malondialdehyde concentration, were observed. Administration of 4% hydrogen via artificial and autologous lungs attenuated endothelial glycocalyx damage caused by partial CPB in rats, which might be mediated by the anti-inflammatory and anti-oxidant properties of hydrogen.

Effect of remimazolam versus sevoflurane on intraoperative hemodynamics in noncardiac surgery: a retrospective observational study using propensity score matching

BACKGROUND

This study compared the effects of remimazolam and sevoflurane on intraoperative hemodynamics including intraoperative hypotension (IOH).

RESULTS

This study involved adult patients undergoing noncardiac surgery using remimazolam (Group R) or sevoflurane (Group S) for maintenance anesthesia, and invasive arterial pressure measurements, from September 2020 to March 2023 at our hospital. IOH was defined as a mean blood pressure < 65 mmHg occurring for a cumulative duration of at least 10 min. A 1:1 propensity score-matching method was used. The primary endpoint was the occurrence of IOH, and the secondary endpoints were the cumulative hypotensive time, incidence of vasopressor use, and dose of vasopressor used (ephedrine, phenylephrine, dopamine, and noradrenaline). Group R comprised 169 patients, Group S comprised 393 patients, and a matched cohort of 141 patients was created by propensity score matching. There was no significant difference in the incidence of IOH between the two groups (85.1% in Group R vs. 91.5% in Group S, p = 0.138). Patients in Group R had a significantly lower cumulative hypotension duration (55 [18-119] vs. 83 [39-144] min, p = 0.005), vasopressor use (81.6% vs. 91.5%, p = 0.023), and dose of ephedrine (4 [0-8] vs. 12 [4-20] mg, p < 0.001) than those in Group S. There were no significant differences in the doses of other vasopressors between groups.

CONCLUSIONS

Compared with sevoflurane, the maintenance of anesthesia with remimazolam was not associated with a decreased incidence of IOH; however, it reduced the cumulative hypotension time, incidence of vasopressor use, and dose of ephedrine.

Serum-Stable and Selective Backbone-N-Methylated Cyclic Peptides That Inhibit Prokaryotic Glycolytic Mutases

N-Methylated amino acids (N-MeAAs) are privileged residues of naturally occurring peptides critical to bioactivity. However, de novo discovery from ribosome display is limited by poor incorporation of N-methylated amino acids into the nascent peptide chain attributed to a poor EF-Tu affinity for the N-methyl-aminoacyl-tRNA. By reconfiguring the tRNA's T-stem region to compensate and tune the EF-Tu affinity, we conducted Random nonstandard Peptides Integrated Discovery (RaPID) display of a macrocyclic peptide (MCP) library containing six different N-MeAAs. We have here devised a "pool-and-split" enrichment strategy using the RaPID display and identified N-methylated MCPs against three species of prokaryotic metal-ion-dependent phosphoglycerate mutases. The enriched MCPs reached 57% N-methylation with up to three consecutively incorporated N-MeAAs, rivaling natural products. Potent nanomolar inhibitors ranging in ortholog selectivity, strongly mediated by N-methylation, were identified. Co-crystal structures reveal an architecturally related Ce-2 Ipglycermide active-site metal-ion-coordinating Cys lariat MCP, functionally dependent on two cis N-MeAAs with broadened iPGM species selectivity over the original nematode-selective MCPs. Furthermore, the isolation of a novel metal-ion-independent Staphylococcus aureus iPGM inhibitor utilizing a phosphoglycerate mimetic mechanism illustrates the diversity of possible chemotypes encoded by the N-MeAA MCP library.

Dexmedetomidine suppresses serum syndecan-1 elevation and improves survival in a rat hemorrhagic shock model

Hemorrhagic shock causes vascular endothelial glycocalyx (EGCX) damage and systemic inflammation. Dexmedetomidine (DEX) has anti-inflammatory and EGCX-protective effects, but its effect on hemorrhagic shock has not been investigated. Therefore, we investigated whether DEX reduces inflammation and protects EGCX during hemorrhagic shock. Anesthetized Sprague-Dawley rats were randomly assigned to five groups (n=7 per group): no shock (SHAM), hemorrhagic shock (HS), hemorrhagic shock with DEX (HS+DEX), hemorrhagic shock with DEX and the α7 nicotinic type acetylcholine receptor antagonist methyllycaconitine citrate (HS+DEX/MLA), and hemorrhagic shock with MLA (HS+MLA). HS was induced by shedding blood to a mean blood pressure of 25–30 mmHg, which was maintained for 30 min, after which rats were resuscitated with Ringer’s lactate solution at three times the bleeding volume. The survival rate was assessed up to 3 h after the start of fluid resuscitation. Serum tumor necrosis factor-alpha (TNF-α) and syndecan-1 concentrations, and wet-to-dry ratio of the heart were measured 90 min after the start of fluid resuscitation. The survival rate after 3 h was significantly higher in the HS+DEX group than in the HS group. Serum TNF-α and syndecan-1 concentrations, and the wet-to-dry ratio of heart were elevated by HS, but significantly decreased by DEX. These effects were antagonized by MLA. DEX suppressed the inflammatory response and serum syndecan-1 elevation, and prolonged survival in rats with HS.

Impact of frailty on super elderly patients with peripheral artery disease from the I-PAD 3 year registry

Background

Unlike age, frailty is often not taken into account in treatment indications of Endovascular treatment (EVT). One of the reason is that there was little known the relationship between frailty and the outcome of EVT for super elderly patients with peripheral artery disease (PAD). We investigate impacts of frailty on the super elderly patient prognosis who underwent EVT.

Purpose

To investigate impacts of frailty on the super elderly patient prognosis who underwent EVT.

Methods

From August 2015 to July 2016, 335 consecutive patients who underwent EVT were enrolled in the I-PAD registry from 7 institutes in Nagano prefecture. Among them, we selected and analyzed 91 super elderly PAD patients (≥80 years-old) and divided them into two groups:those with moderate or higher frailty (Clinical Frailty Scale (CFS) ≥6, n=28) and those without (CFS ≤5, n=63). The primary endpoints were cardiovascular death and major adverse cardiovascular and limb events (MACLE), defined as a composite of cardiovascular death, myocardial infarction, stroke, admission for heart failure, major amputation and revascularization.

Results

The median follow-up period was 2.7 years. Freedom rate from cardiovascular death and MACLE were significantly lower among patients with moderate or higher frailty than among those without (47.0% vs. 58.0%, P=0.03; 39.1% vs. 68.5%, P&lt;0.01).

Conclusion

The prognosis of super elderly patients with moderate or higher frailty is worse than those without.

Funding Acknowledgement

Type of funding source: None

Baseline clinical features in a large-scale registration survey of patient with hypertrophic cardiomyopathy throughout Japan: J-HCM registry study

Background

Hypertrophic cardiomyopathy (HCM) is a most prevalent primary myocardial disorder with heterogeneous clinical features. However, there have been few studies on clinical features of HCM as a prospective cohort. In 2015, we established a large-scale registration survey of patients with HCM throughout Japan, named J-HCM registry study.

Purpose

The aim of this study was to clarify the clinical features of Japanese patients with HCM.

Methods

J-HCM registry study is a prospective, multicenter investigation, consisting of 24 hospitals. This time, we present the baseline clinical characteristics in this survey.

Results

Total 1484 patients were registered. The ages at registration and at diagnosis were 65±15 and 56±17 years, respectively, and 806 patients (54%) were men. Majority of the patients (95%) was NYHA class I or II. With regard to subtypes of HCM, there were 526 patients (36%) in the HCM with left ventricular (LV) outflow tract obstruction, 126 patients (8%) in the mid-ventricular obstruction, 57 patients (4%) in the end-stage phase characterized by LV ejection fraction &lt;50%, and 197 patients (14%) in apical HCM. At registration, 80 patients (6%) had prior successful recovery from sustained ventricular tachycardia or ventricular fibrillation, 162 patients (11%) suffered from heart failure hospitalization, and 64 patients (4%) had history of embolic event. Regarding invasive treatment, 160 patients (10%) had prior septal reduction therapy and 162 patients (11%) had ICD implantation. According to the 2014 European Society of Cardiology Guidelines on sudden cardiac death (SCD) prevention, the study patients were divided into 3 categories by the HCM Risk-SCD calculator: patients distribution, 4% in the high risk group (≥6% calculated HCM Risk-SCD at 5 years), 7% in the intermediate risk group (4% to &lt;6%), 69% in the low risk group (&lt;4%), and 16% in the patients with extreme characteristics (Figure 1).

Conclusions

In this multicenter registration survey of patients with HCM, the baseline clinical characteristics were almost similar to several retrospective large-scale cohorts in Western countries except older age and less symptomatic state. This study will provide important knowledge regarding management of HCM.

Figure 1

Funding Acknowledgement

Type of funding source: None

Desflurane anesthesia shifts the circadian rhythm phase depending on the time of day of anesthesia

Desflurane is one of the most frequently used inhalational anesthetics in clinical practice. A circadian rhythm phase-shift after general anesthesia with sevoflurane or isoflurane has been reported in mice, but few studies have reported this effect with desflurane. In the present study, we examined the rest/activity rhythm of mice by counting the number of running wheel rotations, and we found that desflurane anesthesia caused a phase shift in the circadian rhythm that was dependent on the time of day of anesthesia. We also found that desflurane anesthesia altered the relative mRNA expression of four major clock genes (Per2, Bmal, Clock, and Cry1) in the suprachiasmatic nucleus (SCN). These results are important for elucidating the effects of desflurane on the SCN, which is the master clock for the mammalian circadian rhythm. Further studies on the relationship between anesthesia and circadian rhythm may lead to the prevention and treatment of postoperative complications related to circadian rhythms.

1.2% Hydrogen gas inhalation protects the endothelial glycocalyx during hemorrhagic shock: a prospective laboratory study in rats

PURPOSE

Hydrogen gas (H₂) inhalation improved the survival rate of hemorrhagic shock. However, its mechanisms are unknown. We hypothesized that H₂ protected the endothelial glycocalyx during hemorrhagic shock and prolonged survival time.

METHODS

83 Sprague-Dawley rats were anesthetized with isoflurane. The animals were randomly assigned to 5 groups: room air with no shock, 1.2% H₂ with no shock, room air with shock (Control-S), 1.2% H₂ with shock (H₂1.2%-S), and 3.0% H₂ with shock (H₂3.0%-S). Shock groups were bled to a mean arterial pressure of 30-35 mmHg and held for 60 min, then resuscitated with normal saline at fourfold the amount of the shed blood volume.

RESULTS

The syndecan-1 level was significantly lower in the H₂1.2%-S [8.3 ± 6.6 ng/ml; P = 0.01; 95% confidence interval (CI), 3.2-35.8] than in the Control-S (27.9 ± 17.0 ng/ml). The endothelial glycocalyx was significantly thicker in the H₂1.2%-S (0.15 ± 0.02 µm; P = 0.007; 95% CI, 0.02-0.2) than in the Control-S (0.06 ± 0.02 µm). The survival time was longer in the H₂1.2%-S (327 ± 67 min, P = 0.0160) than in the Control-S (246 ± 69 min). The hemoglobin level was significantly lower in the H₂1.2%-S (9.4 ± 0.5 g/dl; P = 0.0034; 95% CI, 0.6-2.9) than in the Control-S (11.1 ± 0.8 g/dl). However, the H₂3.0%-S was not significant.

CONCLUSIONS

Inhalation of 1.2% H₂ gas protected the endothelial glycocalyx and prolonged survival time during hemorrhagic shock. Therapeutic efficacy might vary depending on the concentration.

P943The impact of diabetes on patients with frail after endovascular treatments: from I-PAD registry

Background

Diabetes mellitus (DM) is known to be one of the risks of arteriosclerosis. However, it is still unknown whether DM is a risk factor also in secondary prevention of frail patients after endovascular treatments (EVT)

Purpose

To investigate impact of diabetes on patients with frail after EVT.

Methods

From July 2015 to July 2016, 371 consecutive PAD patients who performed EVT were enrolled in I-PAD registry. We could conduct follow up survey 361 patients (446 lesions) and divided into 2 groups; with diabetes (185 patients, 226 lesions) or without diabetes (176 patients, 220 lesions) and analyzed. And among them,we selected 96 patients with frail and divided into 2 groups; with diabetes (49 patients, 70 lesions) or without diabetes (46 patients, 58 lesions) and analyzed. We defined frail patients as the patients with Clinical Frailty Scale 5 (mild frail) or higher. The primary end point was all-cause-death and major adverse limb events (MALE: TLR, TVR, major amputations) at 1 year.

Result

At 1 years in the patients group with diabetes, overall survival and freedom from MALE were significantly lower (81.7% vs 95.8% P<0.0001; 80.0% vs 94.6%, P<0.0001) than the group without diabetes.Among the patients with frail, between the patients group with diabetes and the group without, there is no significant differences in overall survival and freedom from MALE (88.2% vs 88.9% P=0.83; 80.7% vs 84.1%, P=0.55) at 5 years.

Conclusion

The prognosis of patients with diabetes after EVT was worse than the patient without. On the other hand, the prognosis of frail patients with diabetes after EVT was no difference with the frail patient without diabetes in this study.

P942Impact of left ventricular ejection fraction in patients with critical limb ischemia: from I-PAD registry

Introduction

In patients with critical limb ischemia (CLI) it is known that malnutrition, low BMI, inflammation and so on are prognostic factors. But, it is unclear whether left ventricular ejection fraction (LVEF) affects prognosis of CLI patients. So we investigated that LVEF affects prognosis of CLI patients.

Methods

From July 2015 to July 2016, 371 consecutive peripheral artery disease patients who performed endovascular treatment (EVT) were enrolled in I-PAD registry. 179 of them were patients with CLI. We could conduct follow up survey about 126 (age 75.5±11.1, men 63.5%) and divided two groups according to their LVEF (group with LVEF≤40%, n=13, group without LVEF≤40%, n=113). The primary end point was major adverse limb events (MALE: TLR, TVR, major amputations) and secondary end point was all-cause death.

Results

The median follow-up period was 11.5±6.7 months. The 18 months MALE rate was significant higher in the group with low LVEF than group without low LVEF (76.9% vs 37.2% p<0.05). The 18months all-cause death tended to be higher in the group with low LVEF, however there was not statistical significance in the two groups (53.8% vs 24.8% p=0.09).

Conclusion

LVEF was associated with MALE in patients with CLI.

P1957Impact of fraility on the super elderly patients with peripheral artery disease

Background

The current consensus is that frail patients have high risks of mortality. However, it remains unclear whether frailty is associated with mortality risks in super-elderly patients with peripheral artery disease (PAD).

Methods

The I-PAD registry was a prospective multicenter observational study involving 12 institutions in Nagano prefecture in Japan. From July 2015 to July 2016, the I-PAD registry enrolled 371 consecutive PAD patients who had undergone endovascular therapy (EVT). Among them, we selected and analysed 109 PAD patients who were >80 years old when they had undergone EVT and divided them into two groups: those with frailty (Clinical Frailty Scale≥5, n=47) and those without frailty (Clinical Frailty Scale≤4, n=62). The primary endpoints were overall survival and major adverse limb events (MALE), defined as a composite of all-cause death, major amputation and revascularization.

Results

The median follow-up period was 1.58±0.3 years. Overall, 109 patients with a mean age of 84.8±4.0 years, of whom 63.3% were men, were included. Overall survival and freedom from MALE were significantly lower among patients with frailty than among those without frailty (60.5% vs. 91.6%, P<0.001; 51.4% vs. 87.5%, P<0.001; respectively).

Conclusion

The prognosis of super-elderly patients with frailty is worse than that of patients without frailty.

P936Impact of left ventricular ejection fraction in patients with peripheral artery disease: from I-PAD registry

Introduction

In patients with peripheral artery disease (PAD) it is known that CVD is one of prognostic factors. But, it is unclear whether left ventricular ejection fraction (LVEF) affects prognosis of PAD patients. So we investigated that LVEF affects prognosis of PAD patients.

Methods

From July 2015 to July 2016, 371 consecutive PAD patients who performed endovascular treatment (EVT) were enrolled in I-PAD registry. We could conduct follow up survey about 337 (age 73.8±9.6, men 72.4%) patients and divided two groups according to their LVEF (group with LVEF≤40%, n=18, group without LVEF≤40%, n=319). The primary end point was major adverse limb events (MALE: TLR, TVR, major amputations) and secondary end point was all-cause death.

Results

The median follow-up period was 13.6±5.7 months. The 18 months MALE and all-cause death rate were significantly higher in the group with low LVEF than group without low LVEF (61.1% vs 21.6% p<0.001, 44.4% vs 11.6% p<0.001).

Conclusion

LVEF was significantly associated with MALE and all-cause death in patients with PAD.

Di-(2-ethylhexyl) phthalate suppresses IL-12p40 production by GM-CSF-dependent macrophages via the PPARα/TNFAIP3/TRAF6 axis after lipopolysaccharide stimulation

Activation of peroxisome proliferator-activated receptor α (PPARα) by di-(2-ethylhexyl) phthalate (DEHP) has an anti-inflammatory effect. This study investigated the potential combined influence of PPARα, tumor necrosis factor α-induced protein 3 (TNFAIP3/A20), and tumor necrosis factor receptor-associated factor 6 (TRAF6) on interleukin (IL)-12p40 production by macrophages exposed to DEHP and stimulated with lipopolysaccharide (LPS). LPS upregulated IL-12p40 expression by granulocyte-macrophage colony-stimulating factor-dependent macrophages (on day 9 of culture), whereas adding DEHP to cultures significantly attenuated the response of IL-12p40 to LPS stimulation. PPARα protein was also reduced by DEHP. Interestingly, transfection of macrophages with small interfering RNA (siRNA) duplexes for PPARα, TNFAIP3/A20, or dual oxidase 2 restored the response of IL-12p40 protein to LPS stimulation in the presence of DEHP. siRNAs for various protein kinase Cs (PKCs) (α, β, γ, or δ) also restored IL-12p40 production by macrophages exposed to LPS and DEHP. While LPS upregulated both IL-12p40 and TNFAIP3/A20 production, adding DEHP to cultures dramatically reduced IL-12p40 and TNFAIP3/A20 levels. Silencing of PKCα reduced TNFAIP3/A20 production, whereas PKCγ siRNA (but not PKCβ or δ siRNA) significantly increased TNFAIP3/A20. TRAF6 was also attenuated by macrophages with DEHP. The PPARα/TNFAIP3/TRAF6 axis may have an important role in the mechanism through which DEHP reduces IL-12p40 production by LPS-stimulated macrophages.

[Changes in the Femoral Vein Diameter due to Lower Limb Flexion]

BACKGROUND

The purpose of this study was to in- vestigate the changes in the femoral vein (FV) diam- eter and the positional relationship during lower limb flexion using ultrasonography.

METHODS

Twenty five male healthy volunteers were positioned in the supine and the hip joint was flexed to the target angles, followed by external rota- tion and abduction of the hip joint (hemi-frog-leg posi- tion). The flexion angle of the hip joint was mea- sured: before flexion (control), and at 30', 450, 60*, 75* flexion. The ultrasonograph transducer was held over the line which was 2 cm distal and parallel to the inguinal ligament Results: Compared with controls, the distance from the skin to the anterior wall of the FV was signifi- cantly shorter at 30 (15.1 mm vs 13.3 mm, P<0.01) and longer at 75" (15.1 mm vs 16.4 mm, P<0.03). The exposed width of the FV (length not overlapped by the femoral artery) was longest at 300(9.9 mm vs 12.1 mm, P<0.01).

CONCLUSIONS

This study demonstrated that the hemi-frog-leg position was associated with significant increases in the diameter and exposed width of the FV. In particular, the most effective angle of the hip joint flexion was about 30*.

[A Case of Rocuronium Anaphylaxis in which Anesthesia was Safely Performed after Selection of an Alternative Drug after a Skin Test]

We report our experience of a patient with a history of anaphylactic shock suspected to be caused by rocuronium who was scheduled to undergo hepatic tumor resection. The patient was a 17-year-old female (height : 166 cm, weight : 46 kg). During general anesthesia at another hospital several years ago, she had an anaphylactic shock, and rocuronium was suspected to be the offending drug. To collect information and search for the cause, skin tests were performed for rocuronium, vecuronium and suxamethonium. She was positive for rocuronium, and negative for other drugs. At anesthesia induction, we administered vecuronium and confirmed no development of anaphylaxis before commencement of surgery. In the perioperative period, she had no symptoms that indicated anaphylaxis. Since there is potential high cross-reactivity among muscle relaxants, it is important to perform a test for alternative drugs when a muscle relaxant may be a cause of anaphylaxis. Selection and administration of an alternative drug should be carefully performed, even when a skin test is negative for the alternative drug.

Development of a microwave ion source for ion implantations

A microwave ion source is expected to have a long lifetime, as it has fewer consumables. Thus, we are in the process of developing a microwave ion source for ion implantation applications. In this paper, we report on a newly developed plasma chamber and the extracted P(+) beam currents. The volume of the plasma chamber is optimized by varying the length of a boron nitride block installed within the chamber. The extracted P(+) beam current is more than 30 mA, at a 25 kV acceleration voltage, using PH3 gas.

[The McGRATH MAC Video Laryngoscope Facilitates Probe Insertion during Transesophageal Echocardiography]

BACKGROUND

A transesophageal echocardiography (TEE) probe is often inserted blindly. However, it is desirable to insert it under visual guidance because the blind technique sometimes causes difficulty and may contribute to serious, but rare, complications. This prospective study compared the usefulness of TEE insertion between a brand-new McGRATH MAC video laryngoscope (McGRATH) and a Macintosh laryngoscope (Macintosh).

METHODS

We randomly assigned 80 adult patients undergoing cardiovascular surgery into two groups according to the laryngoscope used for TEE probe insertion: the McGRATH (McG Group; n = 40) and Macintosh (MC Group; n = 40) groups. End points included patient demographics, procedure duration, and resistance during insertion (grades 1-5).

RESULTS

No differences were found in patient demographics between the groups. There was no significant difference in procedure duration between the groups (P = 0.116). Resistance during insertion was significantly lower in the McG Group than in the MC Group (P < 0.001). There were no failures of insertion in the McG Group.

CONCLUSIONS

There were no failures of insertion in the McG Group. Resistance during insertion was lower with the McGRATH than Macintosh. The McGRATH was shown to be very useful when inserting TEE probes.

[Efficacy and safety of sugammadex (Org 25969) in reversing deep neuromuscular block induced by rocuronium or vecuronium in Japanese patients]

BACKGROUND

Efficacy and safety of sugammadex in reversing neuromuscular block induced by rocuronium or vecuronium were investgated in Japanese patients.

METHODS

We studied 99 Japanese patients undergoing surgery requiring general anesthesia. Patients were allocated randomly to receive intubation dose of rocuronium or vecuronium. During surgery, patients received additional dose of rocuronium or vecuronium for maintenance of deep block. At 1-2 PTC, 0.5-8.0 mg . kg-1 of sugammadex was administered. The neuromuscular block was monitored with acceleromyography using TOF stimuli. Sevoflurane was administered to all treatment groups after intubation.

RESULTS

For the rocuronium-induced neuromuscular block, the mean recovery time of the T4/T1 ratio to 0.9 decreased from 66.9 min in the sugammadex 0.5 mg kg-1 group to 1.3 min in the sugammadex 8.0 mg kg-1 group. For the vecuronium-induced neuromuscular block it decreased from 79.5 min in the sugammadex 0.5 mg . kg-1 group to 2.9 min in the sugammadex 8.0 mg . kg-1 group. No clinical evidence of recurarization or residual curarization was observed.

CONCLUSIONS

The efficacy and safety of sugammadex were confirmed in Japanese surgical patients for reversal from deep block.

Hypocapnia delays subsequent bupivacaine cardiotoxicity in rats under sevoflurane anesthesia

BACKGROUND

Hypocapnia induced following the accidental intravenous infusion of a local anesthetic can mitigate anesthetic toxicity, but the effects of hypocapnia induced prior to local anesthetic infusion are unknown. In this study, we examined the effects of prior hypocapnia on bupivacaine-induced cardiotoxicity in rats.

METHODS

Eighteen Sprague-Dawley rats were randomly divided into two groups: one receiving sevoflurane with normal ventilation (Control Group) and the other receiving sevoflurane with hyperventilation to induce hypocapnia (Hypocapnia Group). After 30 min, both groups received continuous intravenous infusions of 0.25% bupivacaine at 2 mg · kg(-1) · min(-1). The time taken to reach 25% and 50% reductions in heart rate (HR; HR-25%, HR-50%) and mean arterial pressure (MAP; MAP-25%, MAP-50%) from the start of bupivacaine infusion were recorded. The difference between HR-25% and MAP-25% was calculated. The times of the first ventricular premature beat (VPB) and final systole were also recorded.

RESULTS

In the Hypocapnia Group, HR-50%, MAP-25%, and MAP-50% were prolonged compared with the Control Group (P < 0.001). Furthermore, the interval between HR-25% and MAP-25% and the times between the first VPB and final systole were prolonged in the Hypocapnia Group (P < 0.001).

CONCLUSION

In rats under sevoflurane anesthesia, prior hypocapnia delayed the onset of bupivacaine-induced cardiotoxicity. Prior hypocapnia should be avoided during continuous bupivacaine nerve block under general anesthesia, because it may delay the detection of cardiotoxicity.

Development of microwave ion source for industrial applications

A microwave ion source is one of the long-life ion sources. In this paper, we report on the characteristics of the extracted Ar ion beam produced by a microwave ion source under various conditions, in terms of magnetic flux distribution and mass flow, and the stability of the ion beam. The measured spectra show that, under the experimental condition, almost all of produced ions were Ar(+) ions. For more than 6 h, the ion beam was stable.

A preliminary study to determine the diagnostic reference level using dose-area product for limited-area cone beam CT

OBJECTIVES

The aim of this study was to measure the dose-area product (DAP) of limited-area cone beam CT (CBCT) units used by dental offices, and to evaluate the rationale of the DAP with an aid of optically stimulated luminescence (OSL) dosemeter in measuring radiation dose.

METHOD

The DAPs of 21 CBCT units used in the dental offices of Tokyo and the surrounding areas from five different manufacturers were measured using OSL nanoDot dosemeter. An assembly of OSL dosemeters with an X-ray film was exposed by CBCT units at exposure parameters commonly used in each dental office. DAP values were then calculated as expressed in mGy cm(2).

RESULTS

DAP values ranged from 126.7 mGy cm(2) to 1476.9 mGy cm(2), depending on the units used.

CONCLUSION

OSL dosemeter coupled with film can be utilized for a large-scale study to measure DAP. The DAP values for individual CBCT units depend not only on the field of view, but also on the exposure parameters adapted by the dental offices.

Efficacy of adding sodium alginate to omeprazole in patients with nonerosive reflux disease: a randomized clinical trial

Nonerosive reflux disease (NERD) is the most common form of gastroesophageal reflux disease. Patients with NERD have a lower response rate to proton pump inhibitors (PPIs) than patients with erosive esophagitis when gauged from relief of heartburn. Sodium alginate decreases the acidity of refluxate and protects the esophageal mucosa. However, whether the addition of sodium alginate to PPI therapy can improve NERD symptoms remains unknown. Accordingly, the aim of this study was to evaluate the efficacy of adding sodium alginate to basal PPI therapy for NERD. Patients who had experienced heartburn on at least 2 days per week during the 1-month period before entering the study and had no endoscopic mucosal breaks (grade M or N according to Hoshihara's modification of the Los Angeles classification) were randomized to one of two treatments for 4 weeks: omeprazole (20 mg once daily) plus sodium alginate (30 mL four times a day) (group A) or omeprazole (20 mg once daily) alone (group B). Eighty-seven patients were enrolled, and 76 patients were randomly assigned to group A (n = 36) or group B (n = 40). Complete resolution of heartburn for at least 7 consecutive days by the end of treatment was significantly more common in group A (56.7%) than in group B (25.7%). One patient from group A had mild drug-related diarrhea that was not clinically serious. In conclusion, omeprazole combined with sodium alginate was better than omeprazole alone in Japanese patients with NERD.

Characterization of optically stimulated luminescence dosemeters to measure organ doses in diagnostic radiology

OBJECTIVE

The aim of this study was to assess the characteristics of an optically stimulated luminescence dosemeter (OSLD) for use in diagnostic radiology and to apply the OSLD in measuring the organ doses by panoramic radiography.

METHODS

The dose linearity, energy dependency and angular dependency of aluminium oxide-based OSLDs were examined using an X-ray generator to simulate various exposure settings in diagnostic radiology. The organ doses were then measured by inserting the dosemeters into an anthropomorphic phantom while using three panoramic machines.

RESULTS

The dosemeters demonstrated consistent dose linearity (coefficient of variation<1.5%) and no significant energy dependency (coefficient of variation<1.5%) under the applied exposure conditions. They also exhibited negligible angular dependency (≤ 10%). The organ doses of the X-ray as a result of panoramic imaging by three machines were calculated using the dosemeters.

CONCLUSION

OSLDs can be utilized to measure the organ doses in diagnostic radiology. The availability of these dosemeters in strip form proves to be reliably advantageous.

Population-based study of asymptomatic infection with Chlamydia trachomatis among female and male students

There are few epidemiological studies of asymptomatic chlamydial infection among students in non-medical settings with minimal bias and improved accuracy; thus, useful data from screening among students are limited. We aimed to obtain accurate epidemiological information about asymptomatic chlamydial infection among students in non-medical settings. A population-based cross-sectional survey of 10,440 >or=18-year-old asymptomatic students who volunteered for a urine screening test for chlamydia was conducted. The prevalences of asymptomatic infection were 9.5% for women and 6.7% for men. Multivariate analysis revealed the risk factors to be a lifetime history of >or=4 sexual partners for women (odds ratio [OR] 3.17) and inconsistent condom use for men (OR 4.18). For both sexes, younger age at first intercourse was associated with a higher rate of inconsistent condom use. This study produced accurate epidemiological information on asymptomatic chlamydial infection. These results may contribute to the establishment of preventive countermeasures against such infection.

"Living electrode" as a long-lived photoconverter for biophotolysis of water

Living blue-green algae (Mastigocladus laminosus), immobilized on an SnO(2) optically transparent electrode with calcium alginate, functioned as an anodic photoelectrode on continuous illumination for periods of time adequate for use in a conventional electrochemical cell. This "living electrode" shows promise of use as a long-lived photoconverter of solar radiant energy to electric energy and as a suitable replacement for unstable chloroplast systems.

[Thymic cancer with superior vena cava invasion reconstructed by ready-made Y-graft]

A 57-year-old woman was admitted to our hospital with a complaint of left supraclavicular lymph node's swelling in January 2007. Computed tomography (CT) showed the lobulated tumor suspected of superior vena cava (SVC) invasion, located in the anterior mediastinum, 5 x 3 cm in size. The patient underwent thymectomy, resection of SVC, and partial resection of the right upper lobe. SVC was reconstructed by ready-made Y-graft (Hemashied phi 18 x 9 mm). Histopathological diagnosis was thymic cancer, poorly differentiated squamous cell carcinoma. The patient was discharged on 21st postoperative day. Postoperative radiotherapy (RT : 12.6 Gy) was canceled for the side effect. Alternatively, adjuvant chemotherapy [carboplatin (CBDCA) +paclitaxel (PTX)] was administered. Additional RT (50 Gy) was given to the lesion of local recurrence 1 and half year after the operation. The patient was alive without any signs of recurrence after RT. Left side bypass graft was patent at 8 months postoperatively, but was obliterated thereafter. Right side bypass is patent at more than 2 years postoperatively. Ready-made Y-graft can be one of the choices of SVC reconstruction.

Solubilization of excess sludge in activated sludge process using the solar photo-Fenton reaction

The solubilization of excess sludge by the solar photo-Fenton reaction has been investigated for the reduction of excess sludge in the activated sludge process. The solubilization kinetics depended on the dosages of the Fenton reagents, Fe and H(2)O(2). Increases of initial Fe and H(2)O(2) concentrations in their ranges studied in this work continuously enhanced the sludge solubilization. Cell lysis by the photo-Fenton reaction caused the increase in dissolved chemical oxygen demand (COD) in the first step of sludge solubilization. The further oxidative decomposition of the discharged organic compounds by the photo-Fenton reaction led to the decrease in the dissolved COD as the second step of sludge solubilization. The increase of dissolved COD in the first step of sludge solubilization and the consumption of H(2)O(2) could be described by the pseudo-zero order kinetics based on the accumulated light energy. About 40% reduction of mixed-liquor suspended solids (MLSS) by the solar photo-Fenton reaction was found. It was found that solar light used as a light energy source instead of costly and hazardous artificial UV light was very effective. The dissolved COD for solar photo-Fenton reaction increased faster and by 1.5 times as compared with that by artificial UV light.

Tachycardia-dependent right bundle-branch block with supernormal conduction

This paper reports the case of a 76-year-old man in whom atrial flutter with varying atrioventricular block and intermittent right bundle-branch block was found. This is the first report on tachycardia-dependent right bundle-branch block associated with supernormal conduction in a case of atrial flutter. When an impulse is conducted to the ventricles beyond 0.72 s after a QRS complex of right bundle-branch block configuration, the impulse falls after the abnormally long effective refractor period of the right bundle branch and passes through the right bundle branch. When the conducted impulse occurs within 0.72 s after a QRS complex of right bundle-branch block configuration, the impulse usually falls in the refractory period and is blocked in the right bundle branch; however, only when the impulse occurs 0.48 or 0.49 s after that does it fall in the supernormal period and passes through the right bundle branch. The findings in the present report strengthen our previous suggestion that the presence of supernormal conduction plays an important role in the initiation of reentrant ventricular tachycardia.

[Case of facial edema and tongue swelling after aortic surgery in the lateral position]

The facial edema and tongue swelling after oral surgery are not rare complications and many case reports were published, but they were limited after anesthesia for surgery of other parts. A 70-year-old woman who had underwent thoraco-abdominal aortic graft surgery showed severe facial edema and tongue swelling after the surgery in the right lateral position. The tongue was largely protruded outside of the mouse when entering ICU and was gradually improved. Twelve hours later, the tongue was shrunken into the mouse. The patient was moved to a general ward without any complications on the 5th postoperative day. The patient had taken anti-hypertensive drugs including candesartan for a long period. She might have become susceptible to angioedema by angiotensin receptor blocker such as angiotensin-converting enzyme inhibitor and stress of surgery, and anesthesia might have induced a complication of the acute tongue swelling. Although, prevention and treatment of angioedema have not been established, careful observation would be required.