New perforated radiation shield for anesthesiologists: Monte Carlo simulation of effects.

Catheterization for structural heart disease (SHD) requires fluoroscopic guidance, which exposes health care professionals to radiation exposure risk. Nevertheless, existing freestanding radiation shields for anesthesiologists are typically simple, uncomfortable rectangles. Therefore, we devised a new perforated radiation shield that allows anesthesiologists and echocardiographers to access a patient through its apertures during SHD catheterization. No report of the relevant literature has described the degree to which the anesthesiologist's radiation dose can be reduced by installing radiation shields. For estimating whole-body doses to anesthesiologists and air dose distributions in the operating room, we used a Monte Carlo system for a rapid dose-estimation system used with interventional radiology. The simulations were performed under four conditions: no radiation shield, large apertures, small apertures and without apertures. With small apertures, the doses to the lens, waist and neck surfaces were found to be comparable to those of a protective plate without an aperture, indicating that our new radiation shield copes with radiation protection and work efficiency. To simulate the air-absorbed dose distribution, results indicated that a fan-shaped area of the dose rate decrease was generated in the area behind the shield, as seen from the tube sphere. For the aperture, radiation was found to wrap around the backside of the shield, even at a height that did not match the aperture height. The data presented herein are expected to be of interest to all anesthesiologists who might be involved in SHD catheterization. The data are also expected to enhance their understanding of radiation exposure protection.

Preoperative Femoral Nerve Block and Postoperative Sciatic Nerve Block at the Subgluteal Space After Total Knee Arthroplasty: A Retrospective Cohort Study.

Background A preoperative sciatic nerve block (SNB) before total knee arthroplasty (TKA) frequently causes postoperative drop foot; however, this can also occur as an unintended result of surgical invasion. This study assessed the benefits of a postoperative SNB at the subgluteal space for patients who underwent TKA. Methodology This was a single-center, retrospective cohort study. Patients who underwent TKA under general anesthesia between May 2018 and June 2019 at the Teikyo University School of Medicine were screened for inclusion. They received either a preoperative femoral nerve block alone (control group; n = 87) or a preoperative femoral nerve block and postoperative SNB at the subgluteal space (post-SNB group; n = 40). The primary outcome was the pain-related Numerical Rating Scale (NRS) scores. The secondary outcomes were postoperative nausea and vomiting (PONV), intravenous patient-controlled analgesia (iv-PCA) suspension, and postoperative complications. Results No significant differences were observed in the characteristics, NRS scores, time to first drug use for pain, and iv-PCA suspension between groups. However, the incidence of PONV was significantly lower in the post-SNB group (p = 0.03). Logistic regression analysis revealed that droperidol doses of iv-PCA and the presence of postoperative SNB were independently associated with PONV occurrence [A1] {(p = 0.008, 95% confidence intervals (CI) [0.46, 0.89] and (p = 0.02, 95% CI [0.25, 0.88])}. Conclusions A postoperative SNB at the subgluteal space following TKA does not improve postoperative pain control; however, it may have contributed to reduced PONV.

Periarticular multimodal drug injection does not improves early postoperative analgesia compared with continuous interscalene brachial plexus block after arthroscopic rotator cuff repair: A retrospective single-center comparative study.

BACKGROUND: Although continuous interscalene brachial plexus block (CISBPB) is common method in pain management following arthroscopic rotator cuff repair (ARCR), little is known about the analgesic effects of periarticular multimodal drug injection (PMDI) for ARCR. This retrospective study sought to clarify which technique could provide the best analgesic effect after ARCR. METHODS: We retrospectively reviewed consecutive patients who underwent ARCR performed by the same surgeon at our institution between June 2016 and November 2017. Patients who underwent surgery before January 2017 received CISBPB and those who underwent surgery after February 2017 received PMDI for postoperative pain control. Both treatment groups also received fentanyl by intravenous patient-controlled analgesia (IV-PCA). Postoperative pain was evaluated by visual analog scale (VAS) pain scores at 3, 6, 12, 24, and 48 h and need for IV-PCA at 8, 16, and 24 h. RESULTS: Twenty-eight patients received CISBPB and 21 received PMDI. According to the VAS scores, the postoperative analgesic effect was significantly better in the CISBPB group during the first 6 h (p < 0.05). Total fentanyl consumption by IV-PCA during the first 8 postoperative h was significantly greater in the PMDI group than in the CISBPB group. CONCLUSIONS: PMDI does not improve early postoperative analgesia after ARCR compared with CISBPB. CISBPB had a significantly better analgesic effect in the first 8 h postoperatively. LEVEL OF EVIDENCE: Level III.

Accelerated activation of the coagulation pathway during cardiopulmonary bypass in aortic replacement surgery: a prospective observational study.

BACKGROUND: Any form of surgery or tissue damage causes release of tissue factor into the circulation. This may lead to the accelerated consumption of coagulation factors, resulting in severe consumptive coagulopathy. In this study, we compared the molecular markers involved in coagulation activation during cardiopulmonary bypass (CPB) between patients who underwent aortic replacement surgery and those who underwent valve surgery. METHODS: This prospective observational study was performed in each 14 patients who underwent aortic replacement surgery or valve surgery. We evaluated the differences in the levels of fibrinogen, activated factor VII (FVIIa), thrombin-antithrombin complex (TAT), and soluble fibrin monomer complex (SFMC) during surgery between these two groups. RESULTS: The change in fibrinogen levels showed no difference between the groups. The magnitude of increase in TAT was much larger in patients who underwent aortic replacement surgery than in those who underwent valve surgery (173.6 vs. 49.4 ng/mL; p = 0.0001). More importantly, the elevation of FVIIa was significantly higher in patients who underwent aortic replacement (28.5 vs. 19.0 mU/mL; p = 0.0122). The magnitude of increase in SFMC was also larger in the aortic replacement surgery. CONCLUSIONS: The activation of coagulation during CPB was dramatically higher in the aortic replacement surgery compared with the valve surgery, probably owing to the activation of the extrinsic coagulation pathway in the former. This could potentially exacerbate consumptive coagulopathy after CPB termination in patients who underwent aortic replacement, possibly resulting in massive hemorrhage due to impaired hemostasis.

Bronchial blocker lung collapse technique: nitrous oxide for facilitating lung collapse during one-lung ventilation with a bronchial blocker.

BACKGROUND: Effective lung collapse of the nonventilated lung can facilitate thoracic surgery. Previous studies showed that using a bronchial blocker could delay the time of lung collapse compared with using a double-lumen endotracheal tube. We hypothesized that the use of nitrous oxide (N2O) in the inspired gas mixture during 2-lung ventilation would lead to clinically relevant improvement of lung collapse during subsequent 1-lung ventilation with a bronchial blocker. METHODS: Fifty patients were randomized into 2 groups: N2O (n =26) or O2 (n = 24). The N2O group received a gas mixture of oxygen and N2O (FIO2 = 0.5), and the O2 group received 100% oxygen until the start of 1-lung ventilation. Lung isolation was achieved with an Arndt® wire-guided bronchial blocker (Cook® Critical Care, Bloomington, IN. After turning patients to the lateral decubitus position, the cuff of the bronchial blocker was inflated under fiberoptic bronchoscopy surveillance, and thereafter, the dependent lung was ventilated with 100% oxygen during 1-lung ventilation in both groups. Surgeons blinded to the randomization evaluated the degree of lung collapse by using a verbal rating scale (lung collapse scale, 0 = no collapse to 10 = complete collapse) at 5 minutes after opening the pleura. Also, as secondary outcomes, lung collapse at 1 and 10 minutes were evaluated. RESULTS: The score on the lung collapse scale in the N2O group was significantly higher compared with the O2 group at 5 minutes after opening the pleura (7 vs 5, P < 0.001, WMWodds = 7.3, 95% confidence interval (CI), 6.0 to 9.0). It was also higher in the N2O group at 10 minutes (10 vs 7, P < 0.001, WMWodds = 10.1, 95% CI, 1.9-13.3). The lung collapse scale between groups was not significant at 1 minute after opening the pleura (2 vs 2, P = 0.76, WMWodds = 1.1, 95% CI, 0.96-1.2). None of the patients developed hypoxia (SpO2 <92%) during 1-lung ventilation. CONCLUSIONS: Filling the lung with 50% N2O before 1-lung ventilation facilitated lung collapse 5 minutes after opening the chest compared with 100% oxygen when a bronchial blocker was used. The N2O/O2 mixture (FIO2 = 0.5) did not have a harmful effect on subsequent arterial oxygenation during 1-lung ventilation.

Difficulty in placement of a left-sided double-lumen tube due to aberrant tracheobronchial anatomy.

A rare case of a tracheal bronchus coexisting with a left-shifted carina and an acute angle of left main bronchus is presented. A 66 year old man with a history of colon cancer was scheduled for right thoracoscopic pericardial window due to recurrent pericardial effusion. After induction of anesthesia, the trachea was intubated using a 39-French, left-sided double lumen tube (DLT); the DLT was positioned with fiberoptic bronchoscopic guidance. Significantly high airway pressure was noticed as we initiated one-lung ventilation after the patient was positioned in the left lateral decubitus position. While repositioning the DLT, we found an aberrant tracheal bronchus. Although multiple attempts were made to adjust the DLT so as to achieve lung isolation, we could not place the DLT in the appropriate position due to abnormal and distorted anatomy. Lung isolation was unsuccessful; both lungs were carefully ventilated with small tidal volumes.

Papillary muscle sandwich plasty for the treatment of functional mitral valve regurgitation.

We evaluated the availability of original "sandwich plasty" for the treatment of functional mitral regurgitation (FMR) associated with ischemic heart disease (IHD) and aortic valve disease (AVD). Forty-three patients were reviewed, including 27 IHD patients and 16 AVD patients. Preoperatively severe FMR was detected in 14 patients, moderate FMR in 26, and mild FMR in 3. The papillary muscle heads of anterior leaflets and posterior leaflets were approximated using Teflon-pledgeted 3-0 Ticron sutures at anterolateral and posteromedial commissural portions. After surgery, residual moderate FMR was observed in 1 patient and mild FMR in 3 patients. Tenting height of the mitral valve significantly decreased. FMR free rates 2 years after surgery were 93% among IHD patients and 83% in AVD patients. "Sandwich plasty" was simple and effective for the treatment of functional FMR caused by tethering effects due to left ventricular dilatation.

The effects of short interactive animation video information on preanesthetic anxiety, knowledge, and interview time: a randomized controlled trial.

BACKGROUND: We designed an interactive animated video that provides a basic explanation-including the risks, benefits, and alternatives-of anesthetic procedures. We hypothesized that this video would improve patient understanding of anesthesia, reduce anxiety, and shorten the interview time. METHODS: Two hundred eleven patients scheduled for cancer surgery under general anesthesia or combined general and epidural anesthesia, who were admitted at least 1 day before the surgery, were randomly assigned to the video group (n = 106) or the no-video group (n = 105). The patients in the video group were asked to watch a short interactive animation video in the ward. After watching the video, the patients were visited by an anesthesiologist who performed a preanesthetic interview and routine risk assessment. The patients in the no-video group were also visited by an anesthesiologist, but were not asked to watch the video. In both groups, the patients were asked to complete the State-Trait Anxiety Inventory and a 14-point scale of knowledge test before the anesthesiologist's visit and on the day of surgery. We also measured interview time. RESULTS: There was no demographic difference between the 2 groups. The interview time was 34.4% shorter (video group, 12.2 ± 5.3 minutes, vs. no-video group, 18.6 ± 6.4 minutes; 95% confidence interval [CI] for the percentage reduction in time: 32.7%- 44.3%), and knowledge of anesthesia was 11.6% better in the video group (score 12.5 ± 1.4 vs. no-video group score 11.2 ± 1.7; 95% CI for the percentage increase in knowledge: 8.5%-13.9%). However, there was no difference in preanesthetic anxiety between the 2 groups. CONCLUSION: Our short interactive animation video helped patients' understanding of anesthesia and reduced anesthesiologists' interview time.

[Clinical anesthetic training at St. Vincent's Hospital, Melbourne Australia].

Anesthesia training system and operation theater management at St Vincent's hospital Melbourne in Australia, are very well organized, including tutorials, invitation lecture, transesophageal echocardiography conference as well as working hour, operation room, organization of comedical staffs such as nursing and technician staff, and day surgery and anesthesia. Good anesthesia training system and efficient operation theater management are necessary to establish better quality of medical services.