Video versus ultrasound pupillometry for detecting increased pupillary diameters due to nociceptive stimuli: a prospective observational study.

PURPOSE: Ultrasound pupillometry (UP) is a potential alternative to video pupillometry (VP) for assessing changes in patients' pupillary diameter (ΔPD) due to surgical nociception, but the reproducibility of UP and VP has been unclear. We evaluated the reproducibility of nociceptive ΔPD measured with both methods. SUBJECTS AND METHODS: This prospective observational trial with 15 healthy volunteers aged ≥ 18 years was conducted at a Japanese teaching hospital. The ΔPD due to tetanic stimuli randomly applied at 10-60 mA was measured with VP and UP. The primary outcome was the correlation between the ΔPD measured with VP and that measured with UP. The secondary outcome was the agreement between the methods. We also evaluated ΔPD pattern changes due to the raised pain intensity in each method. RESULTS: The noxious ΔPD values of UP were weakly but significantly correlated with those of VP (Spearman's ρ = 0.38, p < 0.001). A significant constant error was identified between the two measurements (Bland-Altman: mean of the difference in ΔPD (VP - UP), - 0.4 [95% CI: - 0.52 to - 0.28, p < 0.001], generalized estimating equation: a beta estimator of ΔPD: 0.41, [95% CI: 0.26-0.56, p < 0.001]). The ΔPD pattern changes due to the raised tetanic stimuli were almost the same in the two methods. CONCLUSION: Due to the significant constant error, we consider the reproducibility of the measured ΔPD between UP and VP moderate. Trial registry number UMIN 000047145. Prior to the subjects' enrollment, the trial was registered with the University Hospital Medical Information Network (Principal investigator: Mao Konno, Date of registration: 3.11.2022). https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000053778 .

Impact of the combination of abdominal peripheral nerve block and neuromuscular blockade on the surgical space during robot-assisted laparoscopic surgery: a prospective randomized controlled study.

PURPOSE: The impact of the combination of abdominal peripheral nerve block (PNB) and the depth of neuromuscular blockade on the surgical field were assessed. METHODS: Thirty-eight patients undergoing elective robot-assisted laparoscopic radical prostatectomy (RARP) were randomized into two groups: a PNB group (moderate neuromuscular block [train-of-four 1-3 twitches] with abdominal PNB) and a non-PNB group (deep neuromuscular block [post-tetanic count 0-2 twitches] without abdominal PNB). The primary outcome was the change in the depth of the abdominal cavity relaxation assessed by the change in the distance (Δdistance) between the umbilicus port and peritoneum upon pneumoperitoneal pressure increase from 8 to 12 mmHg. The secondary outcomes were the CO2 usage for the pneumoperitoneal pressure increase and the subjective differences in the Surgical Rating Score (SRS) during surgery. RESULTS: The Δdistance and the CO2 usage from 8 to 12 mmHg did not differ significantly between the non-PNB and PNB groups (1.34 ± 0.65 vs. 1.28 ± 0.61 cm, p = 0.763 and 3.64 ± 1.68 vs. 4.34 ± 1.44 L, p = 0.180, respectively). There was also no significant difference in SRS. Comparisons of the Δdistance values for pressure increases from 6 to 8 mmHg, 6 to 10 mmHg and 6 to 12 mmHg between the non-PNB and PNB groups also showed no between-group differences, despite significant intra-group differences (p < 0.001) by pressure increment. CONCLUSIONS: Our findings indicate that moderate neuromuscular block with abdominal PNB maintained an adequate surgical space for RARP, with no significant difference from the space achieved by deep neuromuscular block.

Clotting functional stability of withdrawing blood in storage for acute normovolemic hemodilution: a pilot study.

PURPOSE: This study was conducted to time-course changes of clotting function of withdrawing blood for acute normovolemic hemodilution (ANH). METHODS: Twelve enrolled patients who underwent ANH from August, 2018 to January, 2019. Blood was withdrawn into blood collection pack and shaken at 60-80 rpm for 24 h in room temperature. Clot formation was evaluated using rotational thromboelastometry (ROTEM™) just after blood withdrawal (control) and 4, 8, 12 and 24 h after blood withdrawal. We compared with the control value and each value of extrinsically-activated test with tissue factor (EXTEM), intrinsically-activated test using ellagic acid (INTEM) and fibrin-based extrinsically activated test with tissue factor (FIBTEM). RESULTS: Maximum clot firmness (MCF) of FIBTEM did not change significantly. MCF of EXTEM was significantly decreased time-dependent manner but all MCF of EXTEM were within a normal range. Maximum percent change in MCF of EXTEM was 12.4% [95% confidence interval (CI): 9.0-15.8%]. The difference in the maximum clot elasticity (MCE) between EXTEM and FIBTEM (MCEEXTEM-MCEFIBTEM) was significantly decrease from 8 h after blood withdrawal. Maximum percent change in MCEEXTEM-MCEFIBTEM was 30.2% (95% CI:17.6-42.9%) at 24 h after blood withdrawal. CONCLUSION: Even though the MCE significantly decreased in a time-dependent manner, MCF of FIBTEM and EXTEM was normal up to 24 h storage. The blood of ANH can use for the purpose of hemostasis at least 8 h stored at room temperature after blood withdrawal. Future studies are needed to elucidate the clinical impact on the patient after delayed transfusion of ANH blood with regard to patient's hemostasis.

Efficacy of abdominal peripheral nerve block and caudal block during robot-assisted laparoscopic surgery: a retrospective clinical study.

PURPOSE: We retrospectively analyzed the efficacy of abdominal peripheral nerve block (PNB) and caudal block (CB) in patients undergoing robot-assisted laparoscopic radical prostatectomy (RARP). METHODS: Patients who underwent elective RARP at our hospital (Jan. 2015-Sept. 2016) were enrolled. We reviewed the 188 patients' anesthesia charts and medical records and divided the patients into three groups based on the anesthesia used in their cases: 76 patients in the total intravenous anesthesia (TIVA) group, 51 patients in the TIVA + abdominal PNB group (TI-PB group), and 61 patients in the TIVA + abdominal PNB + CB (TI-PB-CB group). We compared the groups' amounts of anesthetic drug usage, anesthesia times, and the presence/absence of additional opioid administration in the recovery room. RESULTS: The perioperative opioid use during anesthesia was significantly greater in the TIVA group than in the TI-PB-CB group. The total amount of muscle relaxant was significantly higher (p < 0.001) in the TIVA group than the TI-PB-CB group: 60.0 (50.0-70.0) mg vs. 50.0 (40.0-60.0) mg. Although there were no significant differences in the operation time, the frequency of the use of additional opioid administration was significantly higher (p < 0.01) in the TIVA group than the TI-PB group: 23.7% vs. 2.0%, respectively. CONCLUSIONS: Although there was no influence on the anesthesia time, the muscle relaxant dose and the perioperative amount of opioid use were significantly less in the combined PNB + CB group. Our analyses suggest that not only PNB but also CB was useful for perioperative management in RARP. CLINICAL TRIAL REGISTRATION: 2016-1059.

Factors affecting phantom limb pain in patients undergoing amputation: retrospective study.

PURPOSE: The efficacy of preemptive analgesia for prevention of phantom limb pain has been controversial although pain management before amputation is empirically important. The aim of this study was to determine the associated factors with perioperative phantom limb pain. METHODS: Following approval by the Medical Ethics Committee in our university, medical records of patients receiving limb amputation surgery in our hospital between April 1, 2013 and October 31, 2017 were retrospectively reviewed. To determine which pre-operative factors could affect the development of phantom limb pain, we performed univariate analysis to find candidate factors (p < 0.05), and then did multivariate regression analysis. RESULTS: Incidence of phantom limb pain was 50% (22/44). There was no difference between the groups in types of anesthesia and post-operative pain levels. The multivariate logistic regression including possible confounders suggested that diabetes mellitus and uncontrollable preoperative pain with non-steroidal anti-inflammatory drugs (NSAIDs) were independently associated with the development of phantom limb pain (Adjusted odds ratio (OR) 0.238 [95% confidential interval (CI) 0.0643-0.883], p = 0.032, Adjusted OR 6.360 [95% CI 1.280-31.50], p = 0.024, respectively). CONCLUSION: The types of anesthesia and the degree of postoperative pain were not related to the development of phantom limb pain. The present data suggest that insufficient preoperative pain with NSAIDs and diabetes mellitus would give an impact on the development of phantom limb pain.

Significance of preoperative butyrylcholinesterase level as an independent predictor of survival in patients with upper urinary tract urothelial carcinoma treated with nephroureterectomy.

OBJECTIVES: Butyrylcholinesterase (BChE) is an alpha-glycoprotein synthesized in the liver. Its serum levels are reportedly correlated with disease activity in patients with cancer. The aim of this study was to estimate the potential prognostic significance of preoperative serum BChE levels in patients with upper urinary tract urothelial carcinoma (UTUC) undergoing radical nephroureterectomy (RNU). METHODS: Of the 220 patients with UTUC who underwent RNU between 1995 and 2016 at Hirosaki University Hospital, 149 patients with available laboratory data were included for analysis. Covariates included age, sex, preoperative laboratory data, clinical T and N grades, tumor grade, tumor location and preoperative chemotherapy. Univariate and multivariate analyses were performed to identify clinical factors associated with overall survival (OS) and disease-free survival (DFS). Univariate analysis was performed using the Kaplan-Meier and log-rank methods, and the multivariate analysis was performed using a Cox proportional hazard model. RESULTS: The median BChE level was 276 U/l and the optimal cut-off point for the serum BChE level was determined to be 218 IU/ml. The 5-year OS and DFS rates were 81.0% and 73.7%, respectively. The 5-year OS and DFS rates were significantly greater in the BChE ≥ 218 than <218 U/l groups (86.6% vs. 53.7%, P < 0.001 and 76.4% vs. 58.3%, P = 0.049, respectively). In multivariate analysis, BChE levels were most significantly associated with OS, whereas BChE level and tumor grade were significantly associated with DFS. CONCLUSIONS: This study validated preoperative serum BChE levels as an independent prognostic factor for UTUC after RNU.

Impact of acute changes in perfusion index and blood pressure on the accuracy of non-invasive continuous hemoglobin concentration measurements during induction of anesthesia.

PURPOSE: Several factors affect the accuracy of non-invasive continuous hemoglobin concentration (SpHb) measurements. We had previously shown an increase in the perfusion index (PI) following induction of anesthesia which was associated with an increase in the difference between SpHb and total hemoglobin (tHb) (SpHb-tHb). We hypothesized that blunting the increase in PI by maintaining blood pressure during induction of anesthesia would improve the agreement between SpHb and tHb measurements. METHODS: Twenty-nine adult patients were enrolled. Patients were randomly assigned by use of sequentially numbered, opaque sealed envelopes to a control (group C) or a phenylephrine group (group P). Anesthesia was induced and maintained with propofol, remifentanil, and ketamine. In group P, phenylephrine was infused at 0.5 µg/kg/min during induction of anesthesia. SpHb and PI were monitored with a Radical-7 Pulse CO-Oximeter. tHb and hematocrit were measured with the ABL800 blood gas analyzer. RESULTS: Following induction of anesthesia, PI increased significantly in both groups (p < 0.001 and p < 0.05 in groups C and P, respectively). However, the increase in PI was significantly smaller in group P than in group C (2.6 ± 1.3 vs 0.8 ± 1.4%, p < 0.001). Similarly, the change in SpHb-tHb was significantly smaller in group P than in group C (0.40 ± 0.78 vs 0.97 ± 0.70 g/dl, p < 0.05). Changes in SpHb-tHb are correlated with changes in PI (r = 0.46, p < 0.05). CONCLUSIONS: The findings suggest that blunting the increase in PI by maintaining arterial pressure during induction of anesthesia improves the agreement between SpHb and tHb values.

[Update on the Use of Lower Extremity Peripheral Nerve Blocks and its Future].

Regional anesthesia for lower limb surgery not only provides satisfactory analgesia, but also improves the overall postoperative outcome with less postoperative nausea and vomiting by decreasing the opioid con- sumption, encouraging early postoperative mobility. Therefore, high-quality anesthesia and postoperative analgesia accelerate the rehabilitation process and shorten the hospital stay. In the past decade, ultra- sound-guided lower extremity peripheral nerve blocks have become popular in Japanese hospitals. This tech- nique enables the visualization of thee target nerve structures, controlles needle movement and the spread of injected local anesthetic solution in a real real-time manner, and this has been adapted not only for tradi- tional blocks, but also in "new approach" blocks such as adductor canal blocks, depending solely on ultra- sound images. In the decades to come, we hope to obtain more established evidence supporting the utility of ultra- sound-guided techniques for lower extremity nerve blocks based on high-quality clinical studies. These findings may support the development of sustained- release formulation local anesthetics and new devices or techniques in the future.

Significance of preoperative butyrylcholinesterase as an independent predictor of biochemical recurrence-free survival in patients with prostate cancer treated with radical prostatectomy.

BACKGROUND: Butyrylcholinesterase (BChE) is an alpha-glycoprotein found in the nervous system and liver. Its serum level is reduced in many clinical conditions, such as liver damage, inflammation, injury, infection, malnutrition, and malignant disease. In this study, we analyzed the potential prognostic significance of preoperative BChE levels in patients with prostate cancer (PCa) undergoing radical prostatectomy (RP). METHODS: We retrospectively evaluated 535 patients with PCa who underwent RP from 1996-2014 at a single institution. Serum BChE was routinely measured in all patients before operation. Covariates included age, preoperative laboratory data [prostate-specific antigen (PSA), hemoglobin, total protein, albumin, BChE, lactate dehydrogenase, C-reactive protein], clinical T, biopsy Gleason score, D'Amico risk classification, and RP with/without neoadjuvant therapy. Univariate and multivariate analyses were performed to identify clinical factors associated with biochemical recurrence-free survival (BRFS). Univariate analyses were performed using the Kaplan-Meier and log-rank methods, and multivariate analysis was performed using a Cox proportional hazard model. RESULTS: The median BChE level was 255 U/L (normal range 168-470 U/L). The median age of the enrolled patients was 68 years, and the median PSA level at diagnosis of PCa was 8.39 ng/mL. The median follow-up period was 65 months. The 5-year BRFS rate was 72.9 %. The 5-year BRFS rates in the BChE ≥ 168 and ≤ 167 U/L groups were 77.7 and 55.0 %, respectively (P < 0.001). In univariate analysis, BChE, cT, biopsy Gleason score, and D'Amico risk classification were significantly associated with BRFS. Multivariate analysis revealed that BChE was significantly associated with BRFS. CONCLUSIONS: This study validated preoperative serum BChE levels as an independent prognostic factor for PCa after RP.

A case report of sudden thrombocytopenia detected only by in vitro analysis.

We experienced an unexpected thrombocytopenia detected only in vitro during radical prostatectomy for a 66-year-old patient. Thrombocytopenia with platelet aggregation was observed in a blood sample obtained using a heparinized syringe (not by ethylene diamine tetra-acetic acid tube). Although we could not exclude platelet agglutination in vivo, no thrombosis or coagulation disorder was observed. We changed the anti-coagulant in the arterial catheter carrier fluid (saline) from heparin to argatroban, and continued with the operation. No embolic complications were observed during the perioperative period. Although pseudothrombocytopenia or heparin-induced thrombocytopenia was highly suspected in the present case, we were not able to confirm which of the two developed. Multi-directional attention and care may be required for perioperative unexpected thrombocytopenia.

The accuracy of non-invasively continuous total hemoglobin measurement by pulse CO-Oximetry undergoing acute normovolemic hemodilution and reinfusion of autologous blood.

BACKGROUND: Non-invasively continuous total hemoglobin (SpHb) measurement has not been assessed adequately in acute bleeding and rapid blood transfusion during surgery. Thus, we have assessed the efficacy of SpHb during both acute normovolemic hemodilution (ANH) and autologous blood transfusion (ABT). METHODS: Twenty-four patients undergoing urological and gynecological surgery were enrolled. ANH was induced by withdrawing blood of 800 g with simultaneous fluid administration. When surgical hemostasis was completed, collected blood was reinfused. Measurement of SpHb, perfusion index (PI) and real total Hb (tHb) were done before and after each 400 ml blood removal (-0, -400, -800 ml) and reinfusion (+0, +400, +800 ml). RESULTS: A Bland-Altman analysis for repeated measurements showed a bias (precision) g/dl of 1.12 (1.25), 1.43 (1.24) and 1.10 (1.23) for all data, during ANH and during ABT, respectively. Additionally, a bias (precision) increased with a reduction in tHb (g/dl): ≥10.0; 0.74 (1.30), 8.0-10.0; 1.15 (1.12) and <8.0; 1.60 (1.28). Although the difference between SpHb and tHb was almost zero before anesthesia induction, it became significant just before ANH and did not change further by ANH and ABT. Significant correlations between SpHb and tHb for all data (r = 0.75, n = 228, p < 0.001) were observed. PI slightly correlated with the difference between SpHb and tHb (r = 0.38, n = 216, p < 0.001). Furthermore, before and after induction of anesthesia, PI also correlated with the difference between SpHb and tHb (r = 0.42, n = 23, p = 0.048 and r = 0.51, n = 22, p = 0.016, respectively). CONCLUSIONS: The present data suggest that SpHb may overestimate tHb during ANH and ABT. In addition, PI and tHb levels had an impact on the accuracy of SpHb measurements.

[Anesthetic Management of Laparoscopic Nephrectomy for a Renal Cancer Patient with Distal Myopathy of Rimmed Vacuole].

A 56-year-old male with distal myopathy of rimmed vacuoles underwent laparoscopic nephrectomy. Anesthesia was induced with propofol, remifentanil and ketamine. Tracheal intubation using McGRATH was uneventful without using muscle relaxants. Then ultrasound-guided right thoracic paravertebral (TPVB) block was performed using 20 ml 0.75% ropivacaine with 10 ml 2% lidocaine by 3 injections of 10 ml each at T9 to T11. General anesthesia was maintained with propofol, remifentanil and ketamine monitoring bispectral index. Good surgical condition and pneumoperitoneum were maintained without using muscle relaxants. His postoperative course was smooth and uneventful, even though a small amount of fentanyl was administrated to relieve wound pain. This case suggests that McGRATH and ultrasound-guided TPVB can be one of the options to avoid using muscle relaxants in patient with neuromuscular disease.

Preoperative butyrylcholinesterase level as an independent predictor of overall survival in clear cell renal cell carcinoma patients treated with nephrectomy.

The prognostic factors for the overall survival (OS) of clear cell renal cell carcinoma (ccRCC) patients treated with nephrectomy are not well defined. In the present study, we investigated the prognostic significance of preoperative butyrylcholinesterase (BChE) levels in 400 ccRCC patients undergoing radical or partial nephrectomy from 1992 to 2013 at our institution. Univariate and multivariate analyses were performed to determine the clinical factors associated with OS. Among the enrolled patients, 302 were diagnosed with organ-confined disease only (T1-2N0M0), 16 with lymph node metastases, and 56 with distant metastases. The median preoperative BChE level was 250 U/L (normal range, 168-470 U/L), and median follow-up period was 36 months. The 3-year OS rate in patients with preoperative BChE levels of ≥100 U/L was significantly higher than in those with levels of <100 U/L (89.3% versus 77.7%, P = 0.004). On univariate analysis, performance status; anemia; hypoalbuminemia; preoperative levels of BChE, corrected calcium, and C-reactive protein; and distant metastasis status were significantly associated with OS. Multivariate analysis revealed that preoperative BChE levels and distant metastasis status were significantly associated with OS. Our findings suggest a possible role of preoperative BChE levels as an independent predictor of OS after nephrectomy in ccRCC patients.

Plasma ropivacaine concentrations after ultrasound-guided transversus abdominis plane block for open retropubic prostatectomy.

PURPOSE: Ropivacaine-induced vasoconstriction may affect the early absorption speed of ropivacaine; however, the effects of dose on pharmacokinetics following transversus abdominis plane (TAP) block have not been studied. In this study, we have examined plasma ropivacaine concentrations following TAP block with various ropivacaine concentrations (0.25, 0.5, and 0.75 %). METHODS: With the approval of our University ethics committee and informed consent, 39 adult patients undergoing open retropubic prostatectomy were enrolled. Patients were randomly assigned to three groups (n = 13 each) receiving TAP block with 20 ml (10 ml each side) of different concentrations of ropivacaine. To determine plasma concentrations, blood samples were drawn before and 15, 30, 45, 60, 90, 120, and 180 min after completion of bilateral TAP blocks. Plasma ropivacaine concentrations were analyzed by gas chromatography with mass spectrometry. RESULTS: We found that the peak plasma concentrations (C(max)) increased dose dependently (0.41 ± 0.14, 0.89 ± 0.55, and 1.56 ± 0.50 µg/ml), but the times to C(max) (23.0 ± 15.8, 23.1 ± 14.5, and 20.8 ± 11.5 min) were not different between 0.25, 0.5, and 0.75 % ropivacaine doses, respectively. Terminal elimination half-life (t(1/2)), total body clearance (CL), and distribution volume (V(d)) were also not different among the three groups. CONCLUSION: Ropivacaine concentration did not alter pharmacokinetic profile following TAP blocks.

Effects of adding epinephrine on the early systemic absorption kinetics of local anesthetics in abdominal truncal blocks.

We evaluated the pharmacokinetics of ropivacaine following rectus sheath block (RSB) and transversus abdominis plane (TAP) block with or without epinephrine. A total of 26 adult patients undergoing lower abdominal surgery with RSB (=RSB trial) and another 26 adult patients undergoing open prostatectomy with TAP block (=TAP trial) were enrolled. Patients were randomly assigned to receive either a mixture of 0.75 % ropivacaine 13.2 mL with 1 % plain lidocaine 6.8 mL (TAP-E(-) and RSB-E(-) groups) or a mixture of 0.75 % ropivacaine 13.2 mL and 1 % lidocaine containing adrenaline (1:100,000) 6.8 mL (TAP-E(+) and RSB-E(+) groups) under general anesthesia. The serum concentrations of ropivacaine were measured using gas chromatography with mass spectrometry. The peak concentration was significantly lower and time to peak concentration was significantly longer in the TAP-E(+) group than in the TAP-E(-) group (P < 0.05 and <0.01, respectively), while there were no significant differences in these parameters between the RSB-E(+) and RSB-E(-) groups. These results indicate that epinephrine attenuates the early phase of local anesthetic absorption from the injected site in TAP blocks, but not RSB.

Anesthetic management of external iliac artery transection in a morbidly obese patient with Klippel-Trenaunay-Weber syndrome: a case report.

BACKGROUND: We report the anesthetic management of an external iliac artery transection in a morbidly obese patient with Klippel-Trenaunay-Weber syndrome (KTWS). CASE PRESENTATION: A 47-year-old man with KTWS was scheduled for a right external iliac artery transection. Preoperative CT showed a right external iliac artery aneurysm, a right superficial femoral artery aneurysm, and developed collateral vessels. General anesthesia was maintained with desflurane, remifentanil, and rocuronium bromide. After the transection of the right external iliac artery, the regional saturation of oxygen (rSO2) value of the right femoral did not decrease. There was no significant hemodynamic change before or after the transection. A non-ultrasound-guided rectus abdominis sheath block was performed due to the many collateral vessels. After extubation, the patient did not complain of postoperative pain. CONCLUSIONS: In the transection of lower-extremity blood arteries under laparotomy in patients with KTWS, rSO2 monitoring, hemodynamic monitoring, and combined regional anesthesia could be useful.

Brief reports: plasma ropivacaine concentrations after ultrasound-guided rectus sheath block in patients undergoing lower abdominal surgery.

A rectus sheath block can provide postoperative analgesia for midline incisions. However, information regarding the pharmacokinetics of local anesthetics used in this block is lacking. In this study, we detail the time course of ropivacaine concentrations after this block. Thirty-nine patients undergoing elective lower abdominal surgery were assigned to 3 groups receiving rectus sheath block with 20 mL of different concentrations of ropivacaine. Peak plasma concentrations were dose dependent, and there were no significant differences in the times to peak plasma concentrations. The present data also suggested a slower absorption kinetics profile for ropivacaine after rectus sheath block than other compartment blocks.

Two cases of circulatory collapse due to suspected remimazolam anaphylaxis.

BACKGROUND: Remimazolam was approved in Japan in January 2020. We report two cases of circulatory collapse due to suspected remimazolam anaphylaxis during anesthetic induction. CASE PRESENTATION: Case 1: A 74-year-old male was scheduled for debridement and skin grafting for a severe burn injury. We induced anesthesia with 4 mg of remimazolam and 20 mg of ketamine. The patient subsequently developed treatment-resistant severe hypotension. Case 2: A 59-year-old male was scheduled for laparoscopic-assisted sigmoid colectomy. We induced anesthesia with 9 mg of remimazolam. Within a few minutes, the patient developed treatment-resistant severe hypotension. As serum tryptase was elevated in both cases and only intravenous administration of adrenaline was effective, we considered the circulatory collapse might be due to anaphylaxis. CONCLUSION: We experienced two cases of circulatory collapse due to suspected remimazolam anaphylaxis during anesthetic induction. The prevalence of remimazolam anaphylaxis is not yet known, and further research is needed.

The role of neutrophil gelatinase-associated lipocalin and iron homeostasis in object recognition impairment in aged sepsis-survivor rats.

Older adult patients with sepsis frequently experience cognitive impairment. The roles of brain neutrophil gelatinase-associated lipocalin (NGAL) and iron in older sepsis patients remain unknown. We investigated the effects of lipopolysaccharide-induced sepsis on novel object recognition test, NGAL levels, an inflammatory mediator tumor necrosis factor-α (TNFα) levels, and iron ion levels in the hippocampus and cortex of young and aged rats. The effect of an iron chelator deferoxamine pretreatment on aged sepsis rats was also examined. Young sepsis-survivor rats did not show impaired novel object recognition, TNFα responses, or a Fe2+/Fe3+ imbalance. They showed hippocampal and cortical NGAL level elevations. Aged sepsis-survivor rats displayed a decreased object discrimination index, elevation of NGAL levels and Fe2+/Fe3+ ratio, and no TNFα responses. Pretreatment with deferoxamine prevented the reduction in the object recognition of aged sepsis-survivor rats. The elevation in hippocampal and cortical NGAL levels caused by lipopolysaccharide was not influenced by deferoxamine pretreatment. The lipopolysaccharide-induced Fe2+/Fe3+ ratio elevation was blocked by deferoxamine pretreatment. In conclusion, our findings suggest that iron homeostasis in the cortex and hippocampus contributes to the maintenance of object recognition ability in older sepsis survivors.

[Risk management in ultrasound-guided regional anesthesia].

The innovation of ultrasound-guided regional anesthesia technique has enabled the anesthesiologist to secure an accurate needle position and to monitor the distribution of the local anesthetic in real time. However, the evidence is necessary concerning increased benefits and reduced complications compared to conventional guidance techniques. This article highlights the importance of acquiring an understanding and knowledge of the complications related to regional anesthesia itself, including neural injury, local anesthetics systemic toxicity and vascular injury. Common complications of nerve blocks can be avoided with major principles of ultrasound-guided technique, which involves similar risk of complications and requires similar amount of knowledge for management. It is necessary to establish the recommendations for the scope of practice, teaching curriculum and the opinion for implementing the medical practice of ultrasound-guided regional anesthesia.