Radial artery catheterization using a novel T-type ultrasound probe: a single-center randomized study.

Ultrasound guidance has been reported to facilitate radial artery catheterization compared with the palpation method. However, a recent meta-analysis showed that there was not significant differences in the first attempt success rate between the long-axis in-plane (LA-IP) method and the short-axis out-of-plane method. In 2023, we started using a novel T-type probe. We can recognize the needle first during the radial artery access with the short-axis view and then dose it with the long-axis view using the T-type probe. Therefore, we hypothesized that the T-type probe-guided method might heighten the first attempt success rate in radial artery catheterization, even for non-expert practitioners, compared with the LA-IP technique. One hundred and fifty adult patients, older than 20 years, ASA I to III, were randomly assigned to the T-type probe-guided group (Group T: n = 75) or the LA-IP group (Group L: n = 75). The primary outcome was the first attempt success rate. The first attempt success rate in Group T (49/71, 69%) was significantly higher than that in Group L (31/68, 46%) (p = 0.0062). The present study showed that the T-type probe might facilitate the radial artery catheterization rather than the LA-IP method.

Incidence of sodium-glucose cotransporter-2 inhibitor-associated perioperative ketoacidosis in surgical patients: a prospective cohort study.

PURPOSE: Sodium-glucose cotransporter 2 inhibitors (SGLT2is) are commonly prescribed anti-diabetic medications with various beneficial effects; however, they have also been associated with ketoacidosis. The aim of this study was to determine the incidence of SGLT2i-associated perioperative ketoacidosis (SAPKA) in surgical patients. METHODS: We conducted a multicenter, prospective cohort study across 16 centers in Japan, enrolling surgical patients with diabetes who were prescribed SGLT2is between January 2021 and August 2022. Patients were monitored until the third postoperative day to screen for SAPKA, defined as urine ketone positivity with a blood pH of < 7.30 and HCO3 level ≤ 18.0 mEq/L, excluding cases of respiratory acidosis. RESULTS: In total, 759 of the 762 evaluated patients were included in the final analysis. Among these, three patients (0.40%) had urine ketones with a blood pH of < 7.30; however, blood gas analysis revealed respiratory acidosis in all three, and none of them was considered to have SAPKA. The estimated incidence of SGLT2i-associated postoperative ketoacidosis was 0% (95% confidence interval, 0%-0.4%). CONCLUSIONS: The observed incidence of SAPKA in our general surgical population was lower than expected. However, given that the study was observational in nature, interpretation of study results warrants careful considerations for biases.

The 10 Hz dynamic response of a fluid-filled pressure monitoring system is a novel alternative to the fast flush test and indicative of unacceptable systolic pressure overshoot.

The standard method for qualitatively evaluating the dynamic response is to see if the gain of the amplitude spectrum curve approaches 1 (input signal = output signal) over the frequency band of the blood pressure waveform. In a previous report, Watanabe reported that Gardner's natural frequency and damping coefficient, which are widely used as evaluation methods, do not reflect the dynamic response of the circuit. Therefore, new parameters for evaluating the dynamic response of pressure monitoring circuits were desired. In this study, arterial pressure catheters with length of 30, 60, 150, and 210 cm were prepared, and a blood pressure wave calibrator, two pressure monitors with analog output and a personal computer were used to analyze blood pressure monitoring circuits. All data collection and analytical processes were performed using step response analysis program. The gain at 10 Hz was close to 1 and the systolic blood pressure difference was small in the short circuits (30 cm, 60 cm), and the gain at 10 Hz was 1.3-1.5 in the 150 cm circuit and over 1.7 in the 210 cm circuit. The difference in systolic blood pressure increased in proportion to the length of the circuit. It could also be inferred that the gain at 10 Hz should be less than 1.2 to meet a clinically acceptable blood pressure difference. In conclusion, the gain at 10 Hz is sufficiently useful as an indicator to determine the correct systolic blood pressure.

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.

Platelet Function Testing Using Sonoclot and TEG6s as a Platelet Transfusion Prediction Tool in Open Heart Surgery.

Introduction The point-of-care test (POCT) is useful for blood coagulation management during cardiovascular surgery. Although thromboelastography (TEG6s) has been reported to have targeted benefits for blood transfusion in cardiac surgery, Sonoclot analysis has not yet been fully validated. In this study, we evaluated the accuracy of Sonoclot, especially platelet function (PF) as a platelet concentrate (PC) transfusion parameter, compared to TEG6s in cardiovascular surgery. Methods This single-center, prospective, randomised trial was conducted at a university hospital. Forty-two adult patients who underwent elective cardiac surgery requiring cardiopulmonary bypass were included in this study between 2017 and 2021. The participants were randomly assigned to the Sonoclot (S) or Sonoclot and TEG6s (ST) groups. The amount of intraoperative PC was determined according to the POCT parameter values at the time of protamine administration. In addition, we investigated the correlation between PF parameters of POCT and platelet count at the end of surgery. Results There was no statistically significant difference in the intraoperative PC volume between the two groups. The Sonoclot PF parameter, PF, was moderately correlated with platelet count at the end of surgery (r=0.5449, p=0.009), and the TEG6s PF parameter showed a strong correlation with platelet count at the end of surgery (r=0.7744, p<0.001). Conclusion There was no statistically significant difference in platelet transfusion volume between the Sonoclot and TEG6s in this study. The correlation between the PF of the Sonoclot and platelet count was moderate. This study suggests that PF of Sonoclot may be a potentiating indicator of PF.

A Prospective Randomized Controlled Trial of the Effect of Maintenance of Continuous Cuff Pressures (20 cmH2O vs 30 cmH2O) on Postoperative Airway Symptoms in Laparoscopic Surgeries.

INTRODUCTION: Recently, laparoscopic surgery has been used in many fields of surgery. It has been reported that cuff pressure becomes high during laparoscopic surgery. Increased cuff pressure may cause postoperative sore throat and hoarseness. Considering previous reports, we hypothesized that maintenance of a fixed low cuff pressure during laparoscopic surgery might be associated with low grades of postoperative sore throat and hoarseness. METHODS: The participants were 100 patients between 20 and 80 years of age who were scheduled to undergo laparoscopic surgery lasting over 2 hours. Patients were randomly allocated to two groups with endotracheal tube cuff pressures fixed at 20 cmH2O (low-pressure group; LPG) and 30 cmH2O (high-pressure group; HPG). We evaluated mainly sore throat and hoarseness on postoperative day 1 using a visual analog scale (VAS; 0-10 cm). Statistical comparisons of values were performed using the unpaired t-test, Mann-Whitney U-test, and chi-square test with values of p < 0.05 considered statistically significant. RESULTS: There were no significant differences in background characteristics between the two groups. Median postoperative scores for the LPG and HPG were 1 (interquartile range, 0-3) and 0 (0-2; p = 0.560) for sore throat and 2 (0-4) and 1 (0-3; p = 0.311) for hoarseness, respectively, and the differences were not significant. CONCLUSION: The effects of maintenance of a fixed low cuff pressure and a fixed high cuff pressure on the degrees of postoperative sore throat and hoarseness after laparoscopic surgery were the same and the grades were low.

The Tip Position of Peripherally Inserted Central Catheters by the Sherlock 3CG System Was Almost Deeper Than Zone B: A Case Series.

A first analysis of deaths due to central venous catheterization (CVC) in Japan in 2017 reported peripherally inserted central catheterization (PICC) as an alternative to CVC. In 2018, Sherlock™ 3CG (C.R. Bard Inc., New Jersey, USA) and Power PICC® became available for use in Japan. The electromagnetic mechanism of the Sherlock 3CG system often eliminates the need for the use of fluoroscopic devices, such as C-arm scanners. In this clinical report, we describe five cases of patients who underwent PICC guided by the Sherlock 3CG system and were evaluated by transesophageal echocardiography (TEE). The patients were adapted for PICC for highly invasive urologic, thoracic, and dental surgery. Also, the positions of the catheter tip were confirmed by TEE in all cases. The mean distance from the access vein to the catheter tip was 41.1 ± 3.8 cm. Chest X-ray analysis showed a mean distance of 40.0 ± 21.5 mm between the carina and catheter tip. Bicaval TEE views showed that the Power PICC tip had not been advanced into the right atrium in any of the cases. We concluded that the tip positions of the Power PICC guided by the Sherlock 3CG system were almost deeper than Zone B and not in the right atrium.

Validity and Utility of Early Parameters in TEG6s Platelet Mapping to Assess the Coagulation Status During Cardiovascular Surgery With Cardiopulmonary Bypass.

Background The aim of this retrospective observational study was to explore the early predictive parameters for maximum amplitudein the kaolin with heparinase (HKH) assay (MAHKH) of TEG6s Platelet Mapping in cardiovascular surgery including cardiopulmonary bypass (CPB) period. The relationship between each parameter of the assay and laboratory data was also assessed. Methods We included the patients who underwent TEG6s Platelet Mapping during cardiovascular surgery under CPB between November 2021 and May 2022. The correlation between MAHKH and the early parameters was assessed. The association between each parameter of Platelet Mapping and a combination of fibrinogen concentration > 150 mg/dL and platelet count > 100,000µL was also evaluated by the receiver operating characteristic (ROC) curve. Results In 23 patients who underwent TEG6s Platelet Mapping during the study period, 62 HKH assay data including 59 pairs of data (HKH assay and laboratory data) were analyzed. K and angle, but not R, were significantly correlated with MAHKH (r [95% CI]: -0.90 [-0.94, -0.83], p < 0.0001 for K, and 0.87 [0.79, 0.92], p < 0.0001 for angle). Furthermore, ROC curves suggested that these parameters predicted a combination of fibrinogen concentration > 150 mg/dL and platelet count > 100,000/µL with high accuracy. Similar results were confirmed in the heparinized blood samples obtained during CPB. Conclusion These findings suggest that not only MAKHK but also K and angle, which are early parameters in the HKH assay, provide clinically significant information that will facilitate rapid decision-making regarding coagulation strategies during cardiovascular surgery including the CPB period.

Effect of desflurane on changes in regional cerebral oxygenation in patients undergoing one-lung ventilation is equivalent to the effect of propofol.

OBJECTIVES: Desaturation is an important clinical problem during one-lung ventilation (OLV) since it may induce cerebral hypoxia. Measurement of cerebral oxygenation has been shown to provide accurate information about episodes of cerebral hypoxemia. The purpose of this study was to compare the effect of desflurane on changes in cerebral oxygenation during OLV with the effect of propofol. METHODS: A randomized, single-blinded, prospective study was conducted. Fifty adult patients who were scheduled to undergo thoracic surgery were randomly assigned to anesthetic management using desflurane with remifentanil (Group D: n = 25) or using propofol and remifentanil (Group P: n = 25). RESULTS: The characteristics of the patients were very similar. Intergroup analysis of changes in cerebral oxygenation showed no significant difference on the operative side (two-way ANOVA, F (7, 368) = 0.425, p = 0.887) or the non-operative side (two-way ANOVA, F (7, 367) = 1.342, p = 0.229). Intragroup analysis of changes in cerebral oxygenation using one-way ANOVA showed no significant difference on the operative side (Group P; p = 0.585, Group D; p = 0.928) or the non-operative side in both groups (Group P; p = 0.657, Group D; p = 0.602). CONCLUSIONS: The effects of desflurane and propofol on changes in cerebral oxygenation in patients undergoing OLV were equivalent. Our results indicated that desflurane might be an appropriate anesthetic during OLV for maintaining cerebral oxygenation with an effective equivalent to that of propofol.

Comparison of Mill Suss™-guided radial artery catheterization with the long-axis in-plane ultrasound-guided method under general anesthesia: a randomized controlled trial.

Continuous arterial blood pressure measurement is an effective perioperative monitoring method in patients with high-risk comorbidities. Recently, ultrasound guidance has been reported to facilitate radial artery catheterization. A new device, Mill Suss™, has also been developed for visualization of the radial artery and superficial veins using near-infrared laser light. In this study, we hypothesized that the Mill Suss-guided method might reduce the time and the number of attempts required for radial artery catheterization under general anesthesia, as compared to the long-axis in-plane ultrasound-guided method. Seventy-two adult patients aged 20-80 years, ASA physical status I or II, were randomly assigned to the Mill Suss-guided group (Group M: n = 36) or ultrasound-guided group (Group U: n = 36). Primary outcomes were the time required for successful radial artery catheterization and the number of cannulation attempts. There were no significant differences in the characteristics of patients between the two groups. The time required for successful radial artery catheterization was significantly shorter in Group M than in Group U. The number of attempts for successful cannulation was not statistically significantly different between the two groups. However, the results might be different among anesthesiologists well experienced in the ultrasound-guided method.

Superior sealing effect of a three-dimensional printed modified supraglottic airway compared with the i-gel in a three-dimensional printed airway model.

PURPOSE: The aim of this study was to compare the force exerted by a three-dimensional (3D) printed modified supraglottic airway (mSGA) vs. that exerted by the i-gel on a 3D printed airway model. METHODS: After a preliminary experiment in Thiel embalmed cadavers, we created a 3D printed mSGA and five 3D printed airway models based on computed tomography data from five female Japanese patients. We compared the force exerted by the i-gel and mSGA on the larynx of the 3D printed airway models. In addition, tidal volumes with insertion of the airway devices into the 3D printed airway model and administration of different levels of pressure-controlled ventilation (PCV) were compared. RESULTS: The values below indicate mean values ± SD (p value, 95% confidence interval) for the mSGA and i-gel, respectively. The forces exerted by the cuff parts were as follows: ventral: 12.5 ± 5.4 vs. 20.7 ± 3.7 N (p = 0.0001, - 10.0 to - 6.5), proximal: 1.9 ± 1.4 vs. 1.7 ± 1.3 N (p = 0.322, - 0.26 to 0.74), and dorsal parts: 6.9 ± 2.2 vs. 12.5 ± 4.8 N (p = 0.0001, - 7.9 to - 3.4), respectively. We also found significantly higher tidal volumes with the mSGA under PCV of 10, 15, and 20 cmH2O. CONCLUSIONS: The method of creating the mSGA that we proposed in this study can be applied to development of novel SGAs that is anatomically more suitable for pharyngolaryngeal structure.

Comparison of the clinical performances of Air-Qsp and i-Gel for airway management under general anesthesia with a muscle relaxant.

STUDY OBJECTIVES: Recently, i-Gel intubating laryngeal airway (ILA) has been frequently used because of the ease for airway insertion by residents and young anesthesiologists. However, it sometimes fails to fit or ventilate sufficiently in Japanese patients. Use of Air-Qsp, which is a new non-inflatable cuffed ILA, in a clinical setting has become possible. The purpose of this study was to compare the clinical performance of Air-Qsp with that of i-Gel for airway management in Japanese adult patients. DESIGN: A randomized, single-blinded, prospective study was conducted after approval from the institutional review board. SETTING: Operating rooms at hospitals. PATIENTS: Thirty-seven adult patients aged 20 to 69 years, with ASA physical status I or II, and scheduled for elective surgery under general anesthesia in the supine position. INTERVENTIONS: Patients were randomly assigned to insertion with Air-Qsp (Group A: n=20) or i-Gel (Group I: n=17). MEASUREMENTS: The number of insertions, duration of insertion, changes in systolic blood pressure and heart rate during insertion, delivered tidal volume for setting volume control ventilation, distribution of the tips of the bronchofiberscopes (BFs) on a clock face, and the number of postoperative complications was evaluated. MAIN RESULTS: Two patients in Group A and one patient in Group I were excluded because insertion of the device failed. There were no significant differences in measured parameters between the 2 groups. The distribution of the tips of the bronchofiberscopes tended to be around the center of the glottis in Group A, whereas they were more toward the 6-o'clock position in Group I. CONCLUSIONS: Air-Qsp is as useful as i-Gel in Japanese patients and the distributions of the tips of BFs through ILAs are different for Air-Qsp and i-Gel.

[A Patient with Klippel-Feil Syndrome Having Difficulties in Inserting and Placing an Endotracheal Tube under General Anesthesia].

A patient with Klippel-Feil syndrome had difficulties in inserting and placing an endotracheal tube under general anesthesia. Klippel-Feil syndrome, characterized by cervical vertebral fusion, scoliosis and endocardiosis, is a rare disease. Anesthesiologists should pay attention to management of anesthesia in airway troubles. A 53-year-old woman diagnosed with Klippel-Feil syndrome was scheduled for general anesthesia with intubation. We tried to insert an endotracheal tube using McGRATH MAC, but it was difficult to insert and place the tube. Finally, we managed to insert a 5.5 mm endotracheal tube. The three-dimensional computed tomography (3D-CT) images after the operation, showed tracheal stenosis at the level of the fourth and fifth cervical vertebrae. In cases where airway difficulties are expected, evaluating 3D-CT images might be useful in airway management.

Comparison of fluid leakage across endotracheal tube cuffs using a three-dimensional printed model of the human trachea.

The objective of this study was to compare fluid leakage across endotracheal tube cuffs using a three-dimensional (3D)-printed human tracheal model that anatomically simulates the human trachea. We made two models based on computed tomography data of the neck and chest. Using a Mallinckrodt Hi-Lo™ (HL), ThinCuff(®) (TC), and Mallinckrodt TaperGuard™ (TG), we sequentially measured the amount of fluid leakage across each endotracheal tube cuff after applying saline or viscous liquid above the cuff. The TG allowed significantly less leakage than the HL and TC with both saline and the viscous liquid. Our study, using a 3D-printed tracheal model, indicated that a conical-shaped endotracheal tube cuff significantly reduces fluid leakage across the cuff compared with conventional cylindrical-shaped cuffs made of polyurethane or polyvinylchloride, contrary to the results of a previous study using a solid cylindrical structure.

A case of hemothorax due to traumatic bleeding managed effectively by Sonoclot®-guided blood transfusion.

A 71-year-old woman was transported to our hospital due to traumatic bleeding, and an operation was immediately performed for achieving hemostasis. We decided to perform Sonoclot®-guided blood transfusion. When Sonoclot signatures had returned normal values, further bleeding did not occur. We experienced the first case of traumatic bleeding managed effectively by using Sonoclot. We suggest that a Sonoclot analyzer may be useful for the management of severe coagulopathy due to traumatic bleeding like ROTEM and TEG.

[Successful Management of Cardiopulmonary Bypass Using Heparin in a Patient with Previous History of Heparin-induced Thrombocytopenia].

Anti-coagulant management of cardiopulmonary bypass for the patient complicated with heparin-induced thrombocytopenia (HIT) is difficult. A woman of late 50's with a previous history of HIT was scheduled for mitral valve replacement, tricuspid valvuloplasty and coronary artery bypass graft. We knew that heparin antibody was negative by serologic and functional assay before the operation. According to the HIT guideline, we planned to use heparin only during cardiopulmonary bypass and to use argatroban for other catheters. Although the platelet count continued decreasing up to the 5th postoperative day unless the transfusion of platelets, heparin antibody was negative on the first postoperative day. But, it was thought that HIT would develop from 5 days to 10 days after using heparin. Therefore, we had to examine heparin antibody on the 5th postoperative day at least for the patients with a history of HIT. In the future, it is important to observe the patient carefully and examine heparin antibody.

[Anesthetic management of an adult patient with Ebstein's anomaly].

Ebstein's anomaly is a rare congenital heart disease. An adult patient with Ebstein's anomaly was scheduled for Hetzer's procedure (modified tricuspid valve repair). This 36-year-old female had been diagnosed as Ebstein's anomaly and a patent foramen ovale during pregnancy, and Hetzer's repair procedure for tricuspid valve incompetence and closure of the foramen ovale were performed. The surgical techniques were chosen based on preoperative transthoracic echocardiography and intraoperative transesophageal echocardiography. During the operation, maximal attention was paid to prevent hypoxemia and paradoxical embolization. The patient's postoperative course was successful, and she was discharged from the hospital on the 14th postoperative day. Tricuspid valve regurgitation was reduced from IV to I, and New York Heart Association functional class was improved from III to I in the postoperative period. Hetzer's procedure is a useful technique for tricuspid repair of Ebstein's anomaly. Accurate morphological evaluation of the tricuspid valve by preoperative transthoracic and intraoperative transesophageal echocardiography is very important for the surgeon to plan surgery appropriately. Anesthesiologists should understand transesophageal echocardiography for congenital heart disease well.