"KAIZEN" method realizing implementation of deep-learning models for COVID-19 CT diagnosis in real world hospitals.

Numerous COVID-19 diagnostic imaging Artificial Intelligence (AI) studies exist. However, none of their models were of potential clinical use, primarily owing to methodological defects and the lack of implementation considerations for inference. In this study, all development processes of the deep-learning models are performed based on strict criteria of the "KAIZEN checklist", which is proposed based on previous AI development guidelines to overcome the deficiencies mentioned above. We develop and evaluate two binary-classification deep-learning models to triage COVID-19: a slice model examining a Computed Tomography (CT) slice to find COVID-19 lesions; a series model examining a series of CT images to find an infected patient. We collected 2,400,200 CT slices from twelve emergency centers in Japan. Area Under Curve (AUC) and accuracy were calculated for classification performance. The inference time of the system that includes these two models were measured. For validation data, the slice and series models recognized COVID-19 with AUCs and accuracies of 0.989 and 0.982, 95.9% and 93.0% respectively. For test data, the models' AUCs and accuracies were 0.958 and 0.953, 90.0% and 91.4% respectively. The average inference time per case was 2.83 s. Our deep-learning system realizes accuracy and inference speed high enough for practical use. The systems have already been implemented in four hospitals and eight are under progression. We released an application software and implementation code for free in a highly usable state to allow its use in Japan and globally.

Analysis of adverse events related to extracorporeal membrane oxygenation from a nationwide database of patient-safety accidents in Japan.

Although adverse events related to extracorporeal membrane oxygenation have been reported, epidemiological data on life-threatening events are insufficient to study the causes of such adverse events. Data from the Japan Council for Quality Health Care database were retrospectively analyzed. The adverse events extracted from this national database included events associated with extracorporeal membrane oxygenation reported between January 2010 and December 2021. We identified 178 adverse events related to extracorporeal membrane oxygenation. At least 41 (23%) and 47 (26%) accidents resulted in death and residual disability, respectively. The most common adverse events were cannula malposition (28%), decannulation (19%), and bleeding (15%). Among patients with cannula malposition, 38% did not undergo fluoroscopy-guided or ultrasound-guided cannulation, 54% required surgical treatment, and 18% required trans-arterial embolization. In this epidemiological study in Japan, 23% of the adverse events related to extracorporeal membrane oxygenation had fatal outcomes. Our findings suggest that a training system for cannulation techniques may be needed, and hospitals offering extracorporeal membrane oxygenation should perform emergency surgeries.

The Accuracy and Potential Racial and Ethnic Biases of GPT-4 in the Diagnosis and Triage of Health Conditions: Evaluation Study.

BACKGROUND: Whether GPT-4, the conversational artificial intelligence, can accurately diagnose and triage health conditions and whether it presents racial and ethnic biases in its decisions remain unclear. OBJECTIVE: We aim to assess the accuracy of GPT-4 in the diagnosis and triage of health conditions and whether its performance varies by patient race and ethnicity. METHODS: We compared the performance of GPT-4 and physicians, using 45 typical clinical vignettes, each with a correct diagnosis and triage level, in February and March 2023. For each of the 45 clinical vignettes, GPT-4 and 3 board-certified physicians provided the most likely primary diagnosis and triage level (emergency, nonemergency, or self-care). Independent reviewers evaluated the diagnoses as "correct" or "incorrect." Physician diagnosis was defined as the consensus of the 3 physicians. We evaluated whether the performance of GPT-4 varies by patient race and ethnicity, by adding the information on patient race and ethnicity to the clinical vignettes. RESULTS: The accuracy of diagnosis was comparable between GPT-4 and physicians (the percentage of correct diagnosis was 97.8% (44/45; 95% CI 88.2%-99.9%) for GPT-4 and 91.1% (41/45; 95% CI 78.8%-97.5%) for physicians; P=.38). GPT-4 provided appropriate reasoning for 97.8% (44/45) of the vignettes. The appropriateness of triage was comparable between GPT-4 and physicians (GPT-4: 30/45, 66.7%; 95% CI 51.0%-80.0%; physicians: 30/45, 66.7%; 95% CI 51.0%-80.0%; P=.99). The performance of GPT-4 in diagnosing health conditions did not vary among different races and ethnicities (Black, White, Asian, and Hispanic), with an accuracy of 100% (95% CI 78.2%-100%). P values, compared to the GPT-4 output without incorporating race and ethnicity information, were all .99. The accuracy of triage was not significantly different even if patients' race and ethnicity information was added. The accuracy of triage was 62.2% (95% CI 46.5%-76.2%; P=.50) for Black patients; 66.7% (95% CI 51.0%-80.0%; P=.99) for White patients; 66.7% (95% CI 51.0%-80.0%; P=.99) for Asian patients, and 62.2% (95% CI 46.5%-76.2%; P=.69) for Hispanic patients. P values were calculated by comparing the outputs with and without conditioning on race and ethnicity. CONCLUSIONS: GPT-4's ability to diagnose and triage typical clinical vignettes was comparable to that of board-certified physicians. The performance of GPT-4 did not vary by patient race and ethnicity. These findings should be informative for health systems looking to introduce conversational artificial intelligence to improve the efficiency of patient diagnosis and triage.

Severe Hyperammonemia Due to Fecal Bowel Obstruction With a Congenital Portosystemic Shunt Resulting in Refractory Status Epilepticus and Cerebral Edema.

Hyperammonemic encephalopathy is a neurological emergency that can lead to seizures and cerebral edema. Although early interventions have been suggested, no clear criteria have been established. Herein, we report a case of severe non-hepatic hyperammonemia resulting in refractory status epilepticus within a day. A 79-year-old woman presented with acute altered mental status. Initial evaluation revealed septic shock and hyperammonemia due to fecal bowel obstruction with congenital portosystemic shunt. The patient was unresponsive to medical treatment and developed refractory status epilepticus. After surgical drainage with colostomy and a decrease in ammonia level, the patient developed cerebral edema and did not recover from the coma. Severe hyperammonemia warrants early intervention, especially in critically ill patients, with treatment of the cause and augmented removal of ammonia with renal replacement therapy.

Bilateral vocal cord palsy induced by long-term use of small-bore nasogastric tube.

Background: Nasogastric tube syndrome is a rare but life-threatening complication of nasogastric tube placement due to acute upper airway obstruction caused by bilateral vocal cord paresis. Case Presentation: An 86-year-old woman was brought to the emergency department with acute stridor. She had been diagnosed with stroke 106 days prior, and an 8F nasogastric tube was placed on the day following the diagnosis. A laryngeal fiberscopy revealed bilateral laryngeal edema and bilateral vocal cord palsy. Nasogastric tube removal and intubation were carried out, and the stridor disappeared. Two days later, a tracheostomy was performed. Unfortunately, the patient's vocal cord function had not improved at the 1 month follow-up upon assessment with a laryngeal fiberscope. Conclusion: Long-term small-bore nasogastric tube placement can cause upper airway obstruction due to bilateral vocal cord palsy.

Obstructive shock due to a spontaneous haemothorax caused by primary lung cancer.

We describe the case of a 67-year-old man with shock and hypoxemia. Chest X-ray showed bilateral lung mass shadows and left pleural effusion with a mediastinal shift, suggesting malignancy. Physical examination and point-of-care ultrasound findings did not suggest obstructive or cardiac shock, but the patient had prolonged shock refractory to fluid and blood transfusion therapy. We inserted a drain into the left thoracic cavity, which enabled the patient to recover from shock. We diagnosed the patient with obstructive and hypovolemic shock due to spontaneous haemothorax caused by primary lung cancer. Tension haemothorax due to malignancy is rare, and when obstructive shock is combined with haemorrhagic shock, it can be very difficult to determine the cause of shock.

Successful treatment of invasive tracheobronchial pulmonary aspergillosis with venovenous extracorporeal membrane oxygenation and combined systemic, intratracheal instillation of liposomal amphotericin B: a case report.

BACKGROUND: Invasive pulmonary Aspergillus and invasive bronchial aspergillosis is a life-threatening opportunistic fungal infection that predominantly affects immunocompromised hosts. A case series and review found that the mortality rate of invasive bronchial aspergillosis is high, at about 40%, and 23.7% of invasive bronchial aspergillosis patients require mechanical ventilator management. There are few reports of life-saving cases with venovenous extracorporeal membrane oxygenation as rescue therapy in invasive pulmonary Aspergillus and invasive bronchial aspergillosis. Here, we report a case of invasive bronchial aspergillosis and invasive pulmonary Aspergillus that was successfully treated with venovenous extracorporeal membrane oxygenation, and combined systemic and intratracheal instillation of liposomal amphotericin B. CASE PRESENTATION: We present the case of a 61-year-old Japanese man with invasive tracheobronchial-pulmonary aspergillosis while receiving chemotherapy for malignant lymphoma. Bronchoscopy revealed trachea covered with pseudomembranous necrotizing tissue, the culture revealed Aspergillus fumigatus, and the histological findings of pseudomembranous revealed fungal hyphae. The patient required venovenous extracorporeal membrane oxygenation because of respiratory failure for atelectasis and obstructive pneumoniae. While continuing systemic administration of liposomal amphotericin B, intratracheal instillation liposomal amphotericin B was performed by bronchoscopy three times a week. Although the respiratory conditions improved and the patient was discontinued on venovenous extracorporeal membrane oxygenation, he ultimately died of recurrence of malignant lymphoma. CONCLUSION: Intratracheal instillation of liposomal amphotericin B is safe, and liposomal amphotericin B instillation allowed a targeted high local drug concentration, which led to improvement in the invasive bronchial aspergillosis. In addition, since the patient was supported with venovenous extracorporeal membrane oxygenation, we were able to perform safe bronchoscopic debridement of airway lesions and intratracheal instillation of liposomal amphotericin B.

Intravascular Catheter Accidentally Placed into the Right Lumbar Vein from the Right Femoral Vein: A Case Report.

BACKGROUND Severe hypothermia has a high mortality rate and necessitates aggressive warming to save lives. One of the most effective treatments for severe hypothermia is intravascular rewarming. Intravascular recuperative warming can be delivered by inserting a catheter through the cervical or femoral veins. Catheter insertion through the femoral vein is a commonly performed procedure with fewer complications than catheter insertion through the internal jugular vein. This procedure is commonly conducted by inserting a central venous catheter through the femoral vein. When a catheter is inserted through the femoral vein, a frontal abdominal radiograph is often used to confirm the position of the catheter tip. CASE REPORT We present the case of a 58-year-old Japanese man who had severe hypothermia. Under ultrasound guidance, a catheter was inserted through the femoral vein into the inferior vena cava for active rewarming. A frontal abdominal radiograph showed that a catheter tip appeared to be in the inferior vena cava. However, a subsequent computed tomography scan revealed that the catheter tip had been misplaced into the right ascending lumbar vein. CONCLUSIONS Catheters may stray into the right ascending lumbar vein if they are placed through the right femoral vein. Frontal abdominal radiographs may be insufficient to confirm catheter placement.

Experimental Implementation of NSER Mobile App for Efficient Real-Time Sharing of Prehospital Patient Information With Emergency Departments: Interrupted Time-Series Analysis.

BACKGROUND: With the aging society, the number of emergency transportations has been growing. Although it is important that a patient be immediately transported to an appropriate hospital for proper management, accurate diagnosis in the prehospital setting is challenging. However, at present, patient information is mainly communicated by telephone, which has a potential risk of communication errors such as mishearing. Sharing correct and detailed prehospital information with emergency departments (EDs) should facilitate optimal patient care and resource use. Therefore, the implementation of an app that provides on-site, real-time information to emergency physicians could be useful for early preparation, intervention, and effective use of medical and human resources. OBJECTIVE: In this paper, we aimed to examine whether the implementation of a mobile app for emergency medical service (EMS) would improve patient outcomes and reduce transportation time as well as communication time by phone (ie, phone-communication time). METHODS: We performed an interrupted time-series analysis (ITSA) on the data from a tertiary care hospital in Japan from July 2021 to October 2021 (8 weeks before and 8 weeks after the implementation period). We included all patients transported by EMS. Using the mobile app, EMS can send information on patient demographics, vital signs, medications, and photos of the scene to the ED. The outcome measure was inpatient mortality and transportation time, as well as phone-communication time, which was the time for EMS to negotiate with ED staffs for transport requests. RESULTS: During the study period, 1966 emergency transportations were made (n=1033, 53% patients during the preimplementation period and n=933, 47% patients after the implementation period). The ITSA did not reveal a significant decrease in patient mortality and transportation time before and after the implementation. However, the ITSA revealed a significant decrease in mean phone-communication time between pre- and postimplementation periods (from 216 to 171 seconds; -45 seconds; 95% CI -71 to -18 seconds). From the pre- to postimplementation period, the mean transportation time from EMS request to ED arrival decreased by 0.29 minutes (from 36.1 minutes to 35.9 minutes; 95% CI -2.20 to 1.60 minutes), without change in time trends. We also introduced cases where the app allowed EMS to share accurate and detailed prehospital information with the emergency department, resulting in timely intervention and reducing the burden on the ED. CONCLUSIONS: The implementation of a mobile app for EMS was associated with reduced phone-communication time by 45 seconds (22%) without increasing mortality or overall transportation time despite the implementation of new methods in the real clinical setting. In addition, real-time patient information sharing, such as the transfer of monitor images and photos of the accident site, could facilitate optimal patient care and resource use.

Adverse events related to thoracentesis and chest tube insertion: evaluation of the national collection of subject safety incidents in Japan.

PURPOSE: Thoracentesis and chest tube insertion are procedures commonly performed in routine clinical practice and are considered mandatory skills for all physicians. Adverse events secondary to these procedures have been widely reported; however, epidemiology data concerning life-threatening events associated with these procedures are lacking. METHODS: We retrospectively analyzed data from the Japan Council for Quality Health Care open database regarding subject safety incidents involving thoracentesis and chest tube insertion. The adverse events extracted from the database included only events associated with thoracentesis and chest tube insertion reported between January 2010 and April 2020. RESULTS: We identified 137 adverse events due to thoracentesis or chest tube insertion. Our analysis also revealed at least 15 fatal adverse events and 17 cases of left/right misalignment. Not only resident doctors but also physicians with 10 years or more of clinical experience had been mentioned in these reports. The most common complications due to adverse events were lung injury (55%), thoracic vascular injury (21%), and liver injury (10%). Surgical treatment was required for 43 (31%) of the 137 cases, and the mortality risk was significantly higher for thoracic vascular injury than for other complications (p = 0.02). CONCLUSION: We identified at least 15 fatal adverse events and 17 cases of left/right misalignment over a 10-year period in the Japan Council for Quality Health Care open database. Our findings also suggest that care should be taken to avoid thoracic vascular injury during chest tube insertion and that immediate intervention is required should such an injury occur.

Association of Initial Potassium Levels with the Type of Stroke in the Emergency Department.

Serum potassium levels are considered as a marker of cerebrovascular emergencies but there is less clarity on the association between initial serum potassium levels recorded on patient's arrival at the emergency department with the type of stroke. This is a case-control study using data of a tertiary care hospital in Japan from April 2018 to September 2019. We identified adult patients with hemorrhagic stroke including subarachnoid hemorrhage (cases) and those with ischemic stroke (controls). Data on age, sex, chief complaints, vital signs, and initial blood tests were collected. We analyzed the association between serum potassium levels and the type of stroke by drawing a LOWESS curve. Additionally, we fitted a logistic regression model to examine the association of interest. There were 416 stroke patients (158 hemorrhagic and 258 ischemic). The median age was 77 years (IQR: 68, 84), and 54% were male. The mean potassium level was 3.69 ± 0.55 mEq/L for hemorrhagic stroke and 4.08 ± 0.65 mEq/L for ischemic stroke. The LOWESS curve showed that the lower initial potassium level was linearly associated with a greater likelihood of hemorrhagic stroke. In the logistic regression model, the odds ratio for the risk of hemorrhagic stroke per 1 mEq/L lower potassium level was 3.31 (95% confidence interval [CI]: 2.24-5.04). This association remained significant in a multivariable model adjusting for other covariates (OR: 2.62 [95% CI: 1.70-4.16]). Initial potassium level was lower in patients with hemorrhagic stroke compared to those with ischemic stroke.

Impact of non-pharmaceutical interventions for the COVID-19 pandemic on emergency department patient trends in Japan: a retrospective analysis.

AIM: The coronavirus disease (COVID-19) pandemic massively impacted emergency department (ED) visits. The unavailability of specific therapies or vaccines has made non-pharmaceutical interventions (NPIs) an alternative strategy for COVID-19. We assessed the impact of NPIs (nationwide school closures and state of emergency) on ED visits during the COVID-19 pandemic in Japan. METHODS: This retrospective study compared the trends in ED visits from 1 January to 25 May, 2020 (during the pandemic) with the average during 2015-2019 (before the pandemic). The primary end-point was the change in the number of ED visits during the COVID-19 pandemic with those from before the pandemic, with the NPI application stratified across four periods in 2020: Period 0 (1-15 January), no COVID-19 cases detected in Japan; Period I (16 January-1 March), initial COVID-19 outbreak; Period II (2 March-15 April), nationwide school closures; Period III (16 April-25 May), state of emergency. RESULTS: Compared with before the pandemic, the number of walk-in ED visits significantly decreased by 23.1%, 12.4%, and 24.0% (4,047 versus 3,111; 3,211 versus 2,813; and 3,384 versus 2,573; P < 0.001 for all) in Periods I, II, and III, respectively. The number of ambulance ED visits during the pandemic significantly increased by 8.3% in Period I (1,814 versus 1,964, P = 0.002), whereas there was no significant change in Periods II and III with 2.7% and -3.1% (1,547 versus 1,589 and 1,389 versus 1,346; P = 0.335 and P = 0.284, respectively). CONCLUSIONS: The application of an NPI during the COVID-19 pandemic could have significantly reduced patient attendance in the ED.

Retrospective Study of Acute Kidney Injury Incidence in Patients with Newly Diagnosed Acute Promyelocytic Leukemia.

PURPOSE: Acute promyelocytic leukemia (APL) constitutes 5-10% of all cases of newly diagnosed acute myeloid leukemia. However, data on the epidemiology and risk factors for acute kidney injury (AKI) in patients with newly diagnosed APL are lacking. This study determined the incidence rate of AKI during induction chemotherapy for patients with newly diagnosed APL and the risk factors for AKI. PATIENTS AND METHODS: We conducted a retrospective observational study of patients with newly diagnosed APL in the Shonan Kamakura General Hospital between April 2004 and April 2020. Data of 27 patients with newly diagnosed APL were analyzed. The patients were classified as no AKI and AKI stages 1, 2 or 3. RESULTS: The incidence rate of AKI during induction chemotherapy was 40% (11/27). Among patients who developed AKI, four patients experienced AKI stage 3, and two patients required renal replacement therapy. No significant differences were found in the white blood cell count and baseline renal function between the groups; however, D-dimer and C-reactive protein levels upon admission were significantly higher in patients with AKI than in patients without AKI. Among patients who developed AKI, in hospital mortality at 90 days was 36% (4/11), which was significantly higher than among patients without AKI (p = 0.02). Patients who developed AKI were administered vancomycin more frequently, while almost all blood culture results were negative. CONCLUSION: Incidence of AKI development in patients with newly diagnosed APL during induction chemotherapy was approximately 40%. Moreover, patients who developed AKI tended to be administered vancomycin more frequently. Unnecessary use of vancomycin should be avoided in patients with newly diagnosed APL, and using alternative non-nephrotoxic drugs should be considered for patients at risk of AKI.

Reversible cerebral vasoconstriction syndrome: the importance of follow-up imaging within 2 weeks.

AIM: In patients with thunderclap headaches, reversible cerebral vasoconstriction syndrome (RCVS) should be considered as a differential diagnosis. However, RCVS diagnosis in the emergency department (ED) remains challenging. This report describes the clinical features and factors related to RCVS diagnosis and suggests diagnostic strategies for its management. METHODS: We retrospectively reviewed the medical records of eight patients diagnosed with RCVS from January 2010 to March 2019 (aged 18-69 years, 5 women). RESULTS: The median duration from the ED visit to RCVS diagnosis was 6 days (range, 1-11 days). Of the eight patients, seven were middle-aged, six had apparent triggers, six had subarachnoid hemorrhage (SAH), five had high systolic blood pressure, and none had any specific abnormality observed upon physical examination. At the initial visit, RCVS was diagnosed in only one patient who had a history of RCVS. Of the other patients, SAH was diagnosed in two, and primary headache was diagnosed in four patients with negative computed tomography (CT) findings. Based on follow-up angiography (e.g., magnetic resonance angiography), seven of eight patients with convexal SAH were diagnosed with RCVS (as the cause of SAH). CONCLUSION: Reversible cerebral vasoconstriction syndrome with negative CT findings at the ED visit was likely to be misdiagnosed as a primary headache. In patients with thunderclap headache and negative CT findings, physicians should consider RCVS as a differential diagnosis, inform patients of the risk of RCVS, and undertake follow-up imaging within 2 weeks.

The tetraspanin CD151 regulates cell morphology and intracellular signaling on laminin-511.

The tetraspanin CD151 forms a stable complex with integrin alpha3beta1, a widely expressed laminin receptor, and is implicated in the regulation of integrin alpha3beta1-mediated cellular responses, including cell attachment, spreading and migration. However, the molecular mechanism by which CD151 regulates integrin alpha3beta1 functions remains unclear. To address this issue, we knocked down CD151 expression in A549 human lung adenocarcinoma cells by RNA interference. When plated on laminin-511 (laminin-10), the CD151-knocked-down cells showed aberrant membrane protrusions and exhibited reductions in the tyrosine phosphorylation of focal adhesion kinase, Src, p130Cas and paxillin. The formation of membrane protrusions was attenuated when the cells were either plated on surfaces coated with higher concentrations of laminin-511 or treated with the integrin beta1-activating mAb TS2/16; however, neither treatment could rescue the reduced tyrosine phosphorylation. These results indicate that CD151 knockdown weakens the integrin alpha3beta1-mediated adhesion to laminin-511 and thereby provokes an aberrant morphology, but this reduced adhesive activity is not involved in the decline of signaling events in CD151-knocked-down cells. Thus, our results suggest that CD151 regulates integrin alpha3beta1 functions in two independent aspects: potentiation of integrin alpha3beta1-mediated cell adhesion and promotion of integrin alpha3beta1-stimulated signaling events involving tyrosine phosphorylation.