Simulation training for medical emergencies: Evaluation of dentists' long-term learning skills and confidence.

INTRODUCTION: As the population ages and more patients experience medical emergencies during dental treatments, dentists must competently and confidently manage these situations. We developed a simulation training course for medical emergencies in the dental setting using an inexpensive vital sign simulation app for smartphones/tablets without the need for an expensive simulator. However, the duration for which this effect is maintained is unclear. This study was performed to evaluate the long-term educational effect at 3, 6, and 12 months after taking the course. MATERIALS AND METHODS: Thirty-nine dental residents participated in this course. Scenarios included vasovagal syncope, anaphylaxis, hyperventilation syndrome, and acute coronary syndrome, each of which the participants had to diagnose and treat. The participants were evaluated using a checklist for anaphylaxis diagnosis and treatment skills immediately after and 3, 6, and 12 months after the course. The participants were also surveyed about their confidence in diagnosing and treating these conditions by questionnaire before, immediately after, and 3, 6, and 12 months after the course. RESULTS: The checklist scores for anaphylaxis were significantly lower at 3, 6, and 12 months after the course than immediately after the course. The percentage of participants who provided a correct diagnosis and appropriate treatment for vasovagal syncope, hyperventilation syndrome, and acute coronary syndrome was lower at all reassessments than immediately after the course. CONCLUSION: Because medical emergency management skills and confidence declined within 3 months, it would be useful to introduce a refresher course approximately 3 months after the initial course to maintain skills and confidence.

A new option for education during surgical procedures and related clinical anatomy in a virtual reality workspace.

The COVID-19 pandemic and mandatory social distancing has brought challenges to anatomy educators who generally need in-person classes. The purpose of this study is to share the experience of a distant online lecture on a surgical procedure and related anatomy in a three-dimensional (3D) virtual reality (VR) workspace and to compare it with reported teaching methods, that is, an in-person class and a Zoom online class. The lecture was delivered by three authors of this article in a VR workspace that enables people to meet through VR. The lectures were about combinations of dental surgical procedures and related clinical anatomy. Physically, the attendees could have been located anywhere in the world, so lecturers joined from the United States and the attendees were all from Japan. VR environment and its flexibility enabled attendees to join the lecture actively, helping them to gain understanding of the surgical procedure and anatomy more efficiently. The use of VR technology with a live communication tool demonstrated in this study has several advantages over previous education methods, although there are still technical issues or disadvantages that need to be addressed. Development of the technology and app/software is required so that more data can be processed at higher speed. Use of VR technology with a live communication tool could be an alternative teaching method. Its overall advantages are a closer look at the slides/monitor and concurrent observation of the multiple assets in various directions by multiple attendees. These advantages cannot be achieved by any other teaching method without VR assets with the workspace provided by Spatial. Even during the mandatory social distancing due to the COVID-19 pandemic, this could enable us to foster 3D understanding of surgery and related anatomy. Further study is now needed to evaluate the effectiveness of this newly proposed teaching method by comparing it with traditional in-person and online classes with a live communication tool.

Junctional Rhythm Preoperatively and During General Anesthesia for Oral and Maxillofacial Surgery.

We report a case of junctional rhythm that occurred both preoperatively and later during a portion of general anesthesia. A 19-year-old woman was scheduled to undergo bilateral sagittal split ramus osteotomy after being diagnosed with a jaw deformity. Preoperative electrocardiography (ECG) revealed a junctional rhythm with a slow heart rate (HR). At 90 minutes after anesthesia induction, local anesthesia with 10 mL of 1% lidocaine and 1:100,000 adrenaline was administered. A junctional rhythm appeared 15 minutes after the local anesthesia. We believe that the atrioventricular nodal pacemaker cells accelerated because of the increased sympathetic activity due to the adrenaline. On the preoperative ECG, the junctional rhythm with slow HR appeared as an escaped beat caused by slowing of the primary pacemaker. Therefore, we think that the preoperative junctional rhythm and the junctional rhythm that appeared during general anesthesia were due to different causes. Understanding the cause of a junctional rhythm could lead to more appropriate treatment. We therefore believe that identifying the cause of the junctional rhythm is important in anesthetic management.

Tension Pneumothorax After Percutaneous Tracheostomy.

A 76-year-old woman with right mandibular gingival cancer was scheduled for surgery. A percutaneous tracheostomy kit was used for tracheostomy under intravenous sedation. After puncturing the cricothyroid membrane, a dilator was inserted along a guidewire. Bucking was observed at the time of insertion of the dilator, despite intratracheal lidocaine spray applied before insertion. After that, the tracheostomy tube was inserted, but no capnographic waveforms appeared when the tube was connected to the anesthesia circuit. Direct macroscopic observation revealed a perforation extending from the posterior wall of the trachea to the anterior wall of the esophagus, which prompted us to request assistance from a thoracic surgeon for treatment before reinserting the tracheostomy tube. After verifying capnographic waveforms on the monitor, anesthesia was induced. Because arterial oxygen saturation was 96% under the administration of pure oxygen, chest radiography was conducted revealing a right pneumothorax. A chest tube was inserted and the patient transported to a nearby general hospital. We suspect that pneumothorax was induced when the integrity of the mediastinal pleura was compromised by mediastinal emphysema because of the injury to the posterior tracheal wall complicated by bucking at the time of insertion of the dilator.

The osteoblastic differentiation ability of human dedifferentiated fat cells is higher than that of adipose stem cells from the buccal fat pad.

OBJECTIVES: The purpose of this study was to evaluate and compare the osteoblastic differentiation ability of dedifferentiated fat (DFAT) cells and adipose stem cells (ASCs) from the buccal fat pad (BFP). MATERIALS AND METHODS: We isolated human DFAT cells and ASCs from the BFP of a patient who underwent oral and maxillofacial surgery and then analyzed their cell surface antigens by flow cytometry. Then, the cells were cultured in osteogenic medium for 14 days. Measurement of bone-specific alkaline phosphatase (BAP), osteocalcin (OCN), and calcium deposition and alizarin red staining were performed to evaluate the osteoblastic differentiation ability of both cell types. RESULTS: ASCs and DFAT cells were positive for CD90 and CD105 and negative for CD11b, CD34, and CD45. BAP (days 3 and 7), OCN (day 14), and calcium deposition (days 7 and 14) within DFAT cell cultures were significantly higher than those in ASC cultures. The alizarin red-stained area in DFAT cell cultures, which indicates mineralized matrix deposition, was stained more strongly than that in ASC cultures. CONCLUSIONS: The cell surface antigens of ASCs and DFAT cells tend to be similar. Furthermore, the osteoblastic differentiation ability of human DFAT cells is higher than that of ASCs from the BFP. CLINICAL RELEVANCE: Isolation of DFAT cells from the BFP has an esthetic advantage because the BFP can be obtained via the oral cavity without injury to the external body surface. Therefore, we consider that DFAT cells from the BFP are an ideal cell source for bone tissue engineering.

Survey on the Awareness of the Use of Oropharyngeal Throat Packs in Dental Anesthesia: An International Online Survey.

INTRODUCTION: Oropharyngeal throat packs (OPTPs) are frequently used to administer general anesthesia during oral surgery and dental procedures. However, the use of OPTPs has remained controversial, with concerns about their effectiveness, the potential for falling short of expectations, and the inherent risk of serious oversight in removing them. This study aimed to assess the awareness of dental anesthesiologists in the United States of America (USA) and Japan regarding the use of OPTPs. METHODS: An online questionnaire was distributed to 41 dental anesthesia education facilities in May 2023 and responses were obtained from 32 facilities. RESULTS: The responses to the questionnaire indicated that dental anesthesiologists in both the USA and Japan believe that using OPTPs during general anesthesia with airway securement is of significant importance, albeit with varying primary purposes for their application. In contrast, notable disparities were observed between the USA and Japan regarding the perceived importance and routine use of OPTPs during open-airway general anesthesia. In both countries, there is a common understanding that the residual risks of OPTPs are severe and that multiple preventive procedures are required. CONCLUSIONS:  The present study showed that dental anesthesiologists in the USA and Japan believed that the use of OPTPs was generally necessary for dental anesthesia. However, there was a difference in awareness between Japan and the USA regarding the importance of OPTPs for open-airway general anesthesia. Therefore, there should be a consensus among dental anesthesiologists in Japan and the USA on using OPTPs during open-airway general anesthesia in the near future.

SARS-CoV-2 recombinant spike protein induces cell apoptosis in rat taste buds.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections can cause loss or alteration of taste and smell as early symptoms or sequelae, but the detailed mechanism behind this phenomenon remains unclear. Here, we investigated whether the SARS-CoV-2 spike protein induces taste cell apoptosis and expression of the apoptosis-related cytokine TNF-α in male Sprague-Dawley rats. Terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP)-fluorescein nick end labeling (TUNEL) assay results revealed a significantly higher apoptosis index for taste cells in the SARS-CoV-2 group than for those in the control group. An immunohistochemistry analysis indicated significantly more TNF-α-positive cells in the SARS-CoV-2 group compared with the control group. These data suggest that the SARS-CoV-2 spike protein promotes taste cell apoptosis and the release of apoptosis-related cytokine TNF-α, implicating its contribution to the taste malfunction caused by coronavirus disease 2019 (COVID-19).

Simulation training for medical emergencies of dental patients: A review of the dental literature.

In recent years, due to the aging of the population, the number of dental patients with comorbidities such as hypertension and diabetes has increased. Although it has been reported that these patients are increasingly developing medical emergencies during their dental treatments, many dental providers still do not possess the skills to manage medical emergencies appropriately. Simulation training is essential to improve this situation however, there is no report describing how to conduct an effective simulation in detail for dental office medical emergencies. The purpose of this review is to provide information on simulations that is effective and practical. The authors will highlight the key characteristics for providing effective simulation trainings, such as the selection of simulators, simulation locations, instructors, debriefings, methods for evaluating educational effectiveness, and the use of telesimulation as a method for simulation training due to the global COVID-19 pandemic. In addition, this review provides recommendations on tailoring an ideal simulation training course for those who wish to create one. The authors hope that this review will promote the spread of effective simulation training and in turn, contribute to improving the medical safety of dental patients.

Safety of COVID-19 vaccine delivery by dentists: An observational cohort study.

Background/purpose: Although many coronavirus disease 2019 (COVID-19) vaccine injections have been administered worldwide, the safety of this practice remains unclear. This study aimed to compare the rates of complications associated with COVID-19 vaccines administered by dentists with those of vaccines administered by nurses. This study aimed to evaluate the safety of a vaccination program delivered by dentists. Materials and methods: This observational cohort study included 537 recipients of the second dose of the Pfizer COVID-19 vaccine, delivered as an intramuscular injection to the upper arm deltoid muscle by dentists or nurses at the study site. Vaccine recipients were divided into two groups according to the vaccination administrator (dentist vs. nurse groups). The rates of complications associated with intramuscular injection technique (numbness in the hand or arm at the time of the injection, vasovagal reflex at the time of the injection, vaccine-related shoulder injury, and prolonged numbness) were examined. Results: A total of 125 vaccine recipients were included (nurse group, n = 84; dentist group, n = 41). The overall incidence rate of complications was lower in the dentist group (2.4%; 1/41) than in the nurse group (8.3%; 7/84). However, this difference was not statistically significant (P = 0.3). Conclusion: This study suggests that the safety of COVID-19 vaccine administration is comparable between dentists and nurses.

Anatomical Study of the Communication Between the Mental Nerve and Marginal Mandibular Branch of the Facial Nerve.

Background Trigeminal-facial nerve communications have been recognized for over 100 years. More specifically, the mental nerve (MN) and marginal mandibular branch of the facial nerve (MMb) communication have been studied but the termination of these branches remains unclear. Therefore, we aim to classify the anatomical communication between the MN and MMb by its course. Methods Sixty sides from thirty adult cadaveric heads were dissected. The communicating branches were dissected and observed anatomically and histologically. Results Communication between the MN and MMb was found on all sides. Based on the course, the communication was classified into two types, superior and anterior. For the superior type, a small branch of the MN and MMb join and travel superiorly to reach the lower lip area. The communication was observed at the level of the mental foramen or above it. For the anterior type, a small branch of the MN and MMb join and travel anteriorly to reach the chin area. The termination was either in the subcutaneous tissue of the chin or in the mentalis. This communication was observed below the mental foramen. Histological observation revealed that these communications contained two or more perineuria. Conclusions Although the function of such neural communications is still unclear, this study helps better understand the anatomical variants of these unions and provides a novel classification system.

The Impact of COVID-19 on Dental Anesthesiologists: An Online Survey of Board-Certified Dental Anesthesiology Specialists of the Japanese Dental Society of Anesthesiology.

OBJECTIVE: The impact of the COVID-19 pandemic on dental anesthesiologists has not been examined. This study aimed to determine how the COVID-19 pandemic affected Japanese dental anesthesiologists' professional lives. METHODS: An online questionnaire related to the effects of COVID-19 on dental anesthesiologists' professional lives was emailed to 351 board-certified dental anesthesiology specialists from the Japanese Dental Society of Anesthesiology. The endpoints of this study were changes in income and job satisfaction as a dental anesthesiologist from 2019 prior to the COVID-19 pandemic. RESULTS: A total of 141 dental anesthesiologists participated in the survey. Most respondents reported no change in income relative to 2019 for 2020 or 2021. Significantly more dental anesthesiologists reported income decreases relative to 2019 for 2020 (39%) vs 2021 (21.3%; P = .001). Very few dental anesthesiologists reported income increases relative to 2019 for 2020 (2.1%) vs 2021 (15.6%; P < .001). Job satisfaction as a dental anesthesiologist remained unchanged for all 3 years. CONCLUSION: Even though many Japanese dental anesthesiologist specialists lost income because of COVID-19, they maintained their job satisfaction.

SARS-CoV-2 recombinant proteins-induced degeneration of taste buds in rat circumvallate papillae.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections cause loss or alteration of taste and smell as early symptoms and sequelae, but the detailed mechanism remains unclear. This study investigated whether coronavirus disease 2019-induced taste disorders are caused by direct effects on taste bud cells. SARS-CoV-2 recombinant spike and nucleocapsid proteins were applied to circumvallate papillae of male Sprague-Dawley rats. Immunohistochemistry and image analysis were used to compare the number of taste buds, and taste bud cells and area, together with confirmation of angiotensin-converting enzyme 2 (ACE2) expression. Immunohistochemical analysis revealed ACE2 expression in the taste buds of rat circumvallate papillae. Decreases in the number of taste buds, taste bud cells, and their area were observed at 12 days after application of SARS-CoV-2 recombinant spike and nucleocapsid proteins. These data suggest that SARS-CoV-2 proteins induce degeneration of taste buds.

[Examination of the optimal midazolam dose required for loss of puncture memory at the time of spinal anesthesia].

BACKGROUND: We examined midazolam ED50 according to age that was necessary for loss of puncture memory at the time of spinal anesthesia and determined whether we could estimate the presence of puncture memory from the degree of sedation after midazolam administration. METHODS: We enrolled patients with ASA PS 1 or 2 and patients from 50 to 80 years of age who had been planned for surgery with spinal anesthesia. We divided the patients into groups according to their age--50s, 60s, and 70s as L, M, and H groups, respectively. We evaluated the degree of sedation with six phases of scores after intravenous administration of midazolam and spinal anesthesia was performed. The midazolam dose was based on the ups and downs method. RESULTS: The midazolam ED50s required for the loss of puncture memory in groups L, M, and H were 0.043, 0.035, and 0.026 mg x kg(-1), respectively. We estimated the association between the sedation degree score after midazolam administration and the puncture memory from ROC curve, but AUC was 0.56 for all cases. CONCLUSIONS: The midazolam ED50 required for the loss of puncture memory decreased with age but it was difficult to estimate puncture memory from the degree of sedation.

Unexpected Anesthetic Circuit Leak Attributed to Improper Use of a Tube Holder: A Case Report.

Leaks involving the anesthesia circuit can cause significant complications including hypoxia and hypoventilation. We present a case of a circuit leak caused by damage to the corrugated tubing attributed to improper use of the tube holder. A 58-year-old male was scheduled for resection of a palatal tumor under an intubated general anesthetic. After successful nasotracheal intubation, the anesthesiologist inserted the corrugated tubing of the anesthetic circuit into the tube holder. A leaking sound was heard and a tear in the corrugated tubing was promptly discovered. The corrugated tubing of the anesthetic circuit presumably tore because it was inserted into the groove of the tube holder at an inappropriate angle with excessive force. Anesthesiologists should be aware of potential leaks if the anesthesia circuit is damaged, which may be caused by improper use of tube holders.

Changes in blood pressure during induction of anesthesia and oral and maxillofacial surgery by type and timing of discontinuation of antihypertensive drugs.

The purpose of this study was to evaluate the effects of an antihypertensive drug class and the timing of discontinuation of antihypertensive therapy on blood pressure during oral and maxillofacial surgery for 129 patients on antihypertensive therapy receiving general anesthesia. Blood pressures at loss of response to stimulation and 5-15 minutes after intubation were significantly lower than those before induction, although the type of antihypertensive therapy did not affect changes in blood pressure. No significant correlation was observed between systolic blood pressure (SBP) on the ward and change in SBP during surgery, though patients with higher blood pressure on the ward tended to exhibit larger differences between SBP on the ward and the lowest SBP during surgery. Frequency of use of vasopressors during surgery was significantly higher in patients who discontinued antihypertensive therapy on the day before surgery than in those who continued antihypertensive therapy on the day of surgery. These findings suggest that appropriate preoperative antihypertensive therapy is important for minimizing change in blood pressure during surgery and preventing perioperative complications. Patients undergoing antihypertensive therapy should be carefully monitored perioperatively by observation for interactions between antihypertensive and anesthetic agents and minimizing interruption schedules for antihypertensive therapy.

Potentiation of Rocuronium Bromide by Lithium Carbonate: A Case Report.

Lithium carbonate is a medication used for the management of various mental disorders. The present report describes a case of prolongation of rocuronium bromide in a patient concurrently taking lithium carbonate. A 64-year-old woman was scheduled to undergo cystectomy under general anesthesia. The patient took lithium carbonate (600 mg/d) for treatment of bipolar affective disorder. General anesthesia was induced with propofol, fentanyl, remifentanil, and sevoflurane. After loss of consciousness, rocuronium bromide (50 mg) was administered, and the trachea was intubated. Approximately 1 hour after the administration of rocuronium, the degree of residual muscle relaxant was evaluated using a nerve stimulation device. No muscle contraction occurred with train-of-four (TOF) stimulation. Following administration of sugammadex (200 mg) the TOF ratio increased to 95%. The ionic size of lithium is similar to that of sodium; therefore, lithium is transported into the cell with sodium. The resting membrane potential decreases, leading to a reduction in the height of the action potential. Thus, the effect of the remaining lithium may have been superimposed on the rocuronium neuromuscular blockade. Evaluation with a nerve stimulation device in patients taking lithium is crucial before extubation because of the risk of rocuronium potentiation.

Utility of the Portex introducer, ivory type, as a tube exchanger.

PURPOSE: This study compared the Portex introducer, ivory type (PII) (Portex Tracheal Tube Introducer; SIMS Portex, Hythe, Kent, England), and Cook Airway Exchange Catheter (CAEC) (Cook, Letchworth, Hertfordshire, England) with regard to success rate of and time required for tracheal intubation by use of each device by oral and maxillofacial surgeons on a manikin. MATERIALS AND METHODS: The subjects comprised 17 oral and maxillofacial surgeons who intubated the trachea of the manikin with each device. The PII or CAEC was inserted into the trachea of the manikin and advanced 26 cm from the upper incisor, and the time required for intubation was measured. The subjects were then asked to rate the difficulty of intubation using a 10-cm visual analog scale. RESULTS: The mean intubation time, averaged over 3 attempts, was significantly shorter for the PII (7.92 +/- 3.15 seconds) than for the CAEC (11.44 +/- 3.98 seconds) (P < .001). The rate of successful intubation with the PII (88.2%) was significantly greater than that with the CAEC (37.3%) (P < .001). With regard to the overall difficulty of intubation, as rated by the 10-cm visual analog scale, the PII (median, 45 mm [10th-90th percentile, 32-53 mm]) was considered less difficult than the CAEC (median, 66 mm [10th-90th percentile, 52-84 mm]) (P < .001). CONCLUSIONS: Intubation is faster, more sure, and easier by use of the PII as a tube exchanger than with the CAEC. This may be particularly important for patients undergoing oral and maxillofacial surgery as a result of anatomic changes in the airway, because edema or hematoma in the upper airway often leads to failed intubation. We conclude that the PII is useful as a tube exchanger.

Comparison of Parker-tipped and Murphy-tipped tracheal tubes in Airway Scope-assisted intubation in a manikin.

PURPOSE: We tested our hypothesis that a Parker-tipped tracheal tube could improve the reliability of tracheal tube passage as compared to a Murphy-tipped tracheal tube during Airway Scope-assisted intubation in a manikin. METHODS: Twenty-seven resident doctors performed Airway Scope-assisted intubations using both tracheal tubes, and the number of times the tracheal tube tip touched the glottis or other laryngeal structures was counted on the Airway Scope monitor. RESULTS: The incidence of the tracheal tube tip touching the glottis during Airway Scope-assisted intubation using the Parker-tipped tracheal tube (7.4%; 2 of 27 attempts) was significantly less than that obtained using the Murphy-tipped tracheal tube (33.3%; 9 of 27 attempts; P = 0.039). CONCLUSION: When the advancement of a conventional tracheal tube during Airway Scope-assisted intubation is likely to result in collision with the glottis or other laryngeal structures, the selection of a Parker-tipped tracheal tube is a better option.