Carboxyhemoglobin in Cardiac Surgery Patients and Its Association with Risk Factors and Biomarkers of Hemolysis.

BACKGROUND: Cardiac surgery with cardiopulmonary bypass (CPB) is associated with hemolysis. Yet, there is no easily available and frequently measured marker to monitor this hemolysis. However, carboxyhemoglobin (CO-Hb), formed by the binding of carbon monoxide (a product of heme breakdown) to hemoglobin, may reflect such hemolysis. We hypothesized that CO-Hb might increase after cardiac surgery and show associations with operative risk factors and indirect markers for hemolysis. METHODS: We conducted a retrospective descriptive cohort study of data from on-pump cardiac surgery patients. We analyzed temporal changes in CO-Hb levels and applied a generalized linear model to assess patient characteristics associated with peak CO-Hb levels. Additionally, we examined their relationship with red blood cell (RBC) transfusion and bilirubin levels. RESULTS: We studied 38,487 CO-Hb measurements in 1735 patients. CO-Hb levels increased significantly after cardiac surgery, reaching a peak CO-Hb level 2.1 times higher than baseline ( P < .001) at a median of 17 hours after the initiation of surgery. Several factors were independently associated with higher peak CO-Hb, including age ( P < .001), preoperative respiratory disease ( P = .001), New York Heart Association Class IV ( P = .019), the number of packed RBC transfused ( P < .001), and the duration of CPB ( P = .002). Peak CO-Hb levels also significantly correlated with postoperative total bilirubin levels (Rho = 0.27, P < .001). CONCLUSIONS: CO-Hb may represent a readily obtainable and frequently measured biomarker that has a moderate association with known biomarkers of and risk factors for hemolysis in on-pump cardiac surgery patients. These findings have potential clinical implications and warrant further investigation.

Reduction Rate of Uric Acid in Blood During Continuous Renal Replacement Therapy for Acute Kidney Injury: A Multicenter Retrospective Observational Study.

INTRODUCTION: Continuous renal replacement therapy (CRRT) eliminates these small solutes with equal efficacy under the same conditions. However, variations in the reduction rates of these solutes observed in patients with CRRT are likely influenced by factors other than removal through CRRT. This study evaluated the reduction rates of these small solutes during CRRT and their possible association with mortality. METHODS: This study used the data of limited patients registered in the CHANGE study, which is a large retrospective observational study on CRRT management across 18 Japanese ICUs. Reduction rates of three solutes in blood, calculated on the 1st and 2nd days, were compared in patients with acute kidney injury (AKI) treated by CRRT. The potential association between solute reduction rates and mortality during CRRT or within 7 days after the termination of CRRT was evaluated. RESULTS: In total, 163 patients with AKI were included in the analysis. The reductuin rates of uric acid (UA) were significantly higher than those of urea and creatinine for the 1st and 2nd tests in the entire cohort. Receiver operating curve (ROC) analysis revealed that lower UA reduction rates were significantly associated with mortality during CRRT or within 7 days after CRRT termination (area under the ROC curve: 0.62 [95% confidence interval {CI} 0.52-0.71] for the 1st test and 0.63 [95%CI 0.54-0.72] for the 2nd test). After adjusting for age and SOFA score, a significant association was observed between lower UA reduction rates and hospital mortality for both tests. CONCLUSION: Among the small solutes, UA reduction rates in patients with AKI treated with CRRT were notably higher than those of creatinine and urea. Furthermore, the significant association between lower UA reduction rates and mortality suggests that UA reduction rate may serve as a valuable indicator of insufficient removal of uremic solutes by CRRT, although the decline in UA production must be taken into account.

Impact of renal dysfunction on the diagnosis of acute pancreatitis using urinary trypsinogen-2: A retrospective study.

AIM: Early diagnosis of acute pancreatitis is crucial, and urinary trypsinogen has been recently reported as a useful biomarker for diagnosing acute pancreatitis. We aimed to evaluate the impact of renal dysfunction on the diagnostic performance of urinary trypsinogen-2 for acute pancreatitis. METHODS: We conducted a retrospective study using the clinical data of patients who visited the Department of Emergency and Critical Care at the University of Tokyo Hospital between 1 October, 2021, and 30 June, 2022. Patients with available data on qualitative urinary trypsinogen-2 levels were identified. We compared the urinary trypsinogen-2 levels among patients who were clinically diagnosed with acute pancreatitis. We further stratified the patients according to renal function parameters, such as serum creatinine level, blood urea nitrogen level, and estimated glomerular filtration rate, and evaluated the performance of urinary trypsinogen-2 as a biomarker for acute pancreatitis. RESULTS: Within 9 months, 35 patients were identified. Of them, 22 patients showed positive results and 13 showed negative results on the urinary trypsinogen-2 test. The sensitivity, specificity, positive predictive value, and negative predictive value were 0.80, 0.40, 0.18, and 0.92, respectively. Based on the blood urea nitrogen level and estimated glomerular filtration rate, the prevalence of false-positive results was significantly higher in patients with reduced renal function than in those with normal renal function. CONCLUSION: In patients with reduced renal function, the urinary trypsinogen-2 qualitative test results might be interpreted with caution when used for diagnosing acute pancreatitis.

Artificial intelligence-assisted interventions for perioperative anesthetic management: a systematic review and meta-analysis.

BACKGROUND: Integration of artificial intelligence (AI) into medical practice has increased recently. Numerous AI models have been developed in the field of anesthesiology; however, their use in clinical settings remains limited. This study aimed to identify the gap between AI research and its implementation in anesthesiology via a systematic review of randomized controlled trials with meta-analysis (CRD42022353727). METHODS: We searched the databases of Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica Database (Embase), Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), Institute of Electrical and Electronics Engineers Xplore (IEEE), and Google Scholar and retrieved randomized controlled trials comparing conventional and AI-assisted anesthetic management published between the date of inception of the database and August 31, 2023. RESULTS: Eight randomized controlled trials were included in this systematic review (n = 568 patients), including 286 and 282 patients who underwent anesthetic management with and without AI-assisted interventions, respectively. AI-assisted interventions used in the studies included fuzzy logic control for gas concentrations (one study) and the Hypotension Prediction Index (seven studies; adding only one indicator). Seven studies had small sample sizes (n = 30 to 68, except for the largest), and meta-analysis including the study with the largest sample size (n = 213) showed no difference in a hypotension-related outcome (mean difference of the time-weighted average of the area under the threshold 0.22, 95% confidence interval -0.03 to 0.48, P = 0.215, I2 93.8%). CONCLUSIONS: This systematic review and meta-analysis revealed that randomized controlled trials on AI-assisted interventions in anesthesiology are in their infancy, and approaches that take into account complex clinical practice should be investigated in the future. TRIAL REGISTRATION: This study was registered with the International Prospective Register of Systematic Reviews (PROSPERO ID: CRD42022353727).

Carboxyhemoglobin as Potential Biomarker for Cardiac Surgery Associated Acute Kidney Injury.

OBJECTIVES: Carboxyhemoglobin (CO-Hb) is a marker of hemolysis and inflammation, both risk factors for cardiac surgery-associated AKI (CSA-AKI). However, the association between CO-Hb and CSA-AKI remains unknown. DESIGN: A retrospective cohort study. SETTING: Tertiary university-affiliated metropolitan hospital: single center. PARTICIPANTS: Adult on-pump cardiac surgery patients from July 2014 to June 2022 (N = 1,698). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients were stratified into quartiles based on CO-Hb levels at intensive care unit (ICU) admission. A progressive increased risk of CSA-AKI was observed with higher CO-Hb levels at ICU admission. On multivariable logistic regression analysis, the highest quartile (CO-Hb ≥ 1.4%) showed an independent association with the occurrence of CSA-AKI (odds ratio 1.45 compared to the lowest quartile [CO-Hb < 1.0%], 95% CI 1.023-2.071; p = 0.038). Compared to patients with CO-Hb <1.4%, patients with CO-Hb ≥ 1.4% at ICU admission had significantly higher postoperative creatinine (135 vs 116 µmol/L, p < 0.001), higher rates of postoperative RRT (6.7% vs 2.3%, p < 0.001) and AKI (p < 0.001) on univariable analysis and shorter time to event for AKI or death (p < 0.001). CONCLUSIONS: CO-Hb ≥ 1.4% at ICU admission is an independent risk factor for CSA-AKI, which is easily obtainable and available on routine arterial blood gas measurements. Thus, CO-Hb may serve as a practical and biologically logical biomarker for risk stratification and population enrichment in trials of CSA-AKI prevention.

Risk of postoperative pneumonia after extubation with the positive pressure versus normal pressure technique: a single-center retrospective observational study.

PURPOSE: A normal pressure extubation technique (no lung inflation before extubation), proposed by the Japanese Society of Anesthesiologists to prevent droplet infection during the coronavirus disease 2019 (COVID-19) pandemic, could theoretically increase postoperative pneumonia incidence compared with a positive pressure extubation technique (lung inflation before extubation). However, the normal pressure extubation technique has not been adequately evaluated. This study compared postoperative pneumonia incidence between positive and normal pressure extubation techniques using a dataset from the University of Tsukuba Hospital. METHODS: In our hospital, the extubation methods changed from positive to normal pressure extubation techniques on March 3, 2020 due to the COVID-19 pandemic. Thus, we compared the risk of postoperative pneumonia between the positive (April 1, 2017 to December 31, 2019) and normal pressure extubation techniques (March 3, 2020 to March 31, 2022) using propensity score analyses. Postoperative pneumonia was defined using the International Classification of Diseases, 10th Edition (ICD-10) codes (J13-J18), and we reviewed the medical records of patients flagged with these ICD-10 codes (preoperative pneumonia and ICD-10 codes for prophylactic antibiotic prescriptions for pneumonia). RESULTS: We identified 20,011 surgeries, including 11,920 in the positive pressure extubation group (mean age 48.2 years, standard deviation [SD] 25.2 years) and 8,091 in the normal pressure extubation group (mean age 47.8 years, SD 25.8 years). The postoperative pneumonia incidences were 0.19% (23/11,920) and 0.17% (14/8,091) in the positive and normal pressure extubation groups, respectively. The propensity score analysis using inverse probability weighting revealed no significant difference in postoperative pneumonia incidence between the two groups (adjusted odds ratio 0.98, 95% confidence interval 0.50 to 1.91, P = 0.94). CONCLUSIONS: These results indicated no increased risk of postoperative pneumonia associated with the normal pressure extubation technique compared with the positive pressure extubation technique. CLINICAL TRIAL NUMBER: Clinical trial number: UMIN000048589 https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000055364.

The Effect of Home Care Support Clinics on Hospital Readmission in Heart Failure Patients in Japan.

BACKGROUND: Heart failure is common and is associated with high rates of hospitalization. Home care support clinics/hospitals (HCSCs) and enhanced HCSCs were introduced in Japan in 2006 and 2012, respectively. OBJECTIVE: This study aimed to examine the effect of post-discharge care by conventional or enhanced HCSCs on readmission, compared with general clinics. DESIGN: Retrospective cohort study using the Japanese nationwide health insurance claims database. PARTICIPANTS: Participants were ≥65 years of age, admitted for heart failure and discharged between July 2014 and August 2015 and received a home visit within a month following the discharge (n=12,393). MAIN MEASURES: The exposure was the type of medical facility that provides post-discharge home healthcare: general clinics, conventional HCSCs, and enhanced HCSCs. The primary outcome was all-cause readmission for 6 months after the first visit; the incidence of emergency house calls was a secondary outcome. We used a competing risk regression using the Fine and Gray method, in which death was regarded as a competing event. KEY RESULTS: At 6 months, readmissions were lower in conventional (38%) or enhanced HCSCs (38%) than general clinics (43%). The adjusted subdistribution hazard ratio (sHR) of readmission was 0.87 (95% CI: 0.78-0.96) for conventional and 0.86 (0.78-0.96) for enhanced HCSCs. Emergency house calls increased with conventional (sHR: 1.77, 95% CI:1.57-2.00) and enhanced HCSCs (sHR: 1.93, 95% CI: 1.71-2.17). CONCLUSIONS: Older Japanese patients with heart failure receiving post-discharge home healthcare by conventional or enhanced HCSCs had lower readmission rates, possibly due to compensation with more emergency house calls. Conventional and enhanced HCSCs may be effective in reducing the risk of rehospitalization. Further studies are necessary to confirm the medical functions performed by HCSCs.

Association between advanced care planning and emergency department visits: A systematic review.

BACKGROUND: Advance care planning can help provide optimal medical care according to a patient's wishes as a part of patient-centered discussions on end-of-life care. This can prevent undesired transfers to emergency departments. However, the effects of advance care planning on emergency department visits and ambulance calls in various settings or specific conditions remain unclear. AIM: To evaluate whether advanced care planning affected the frequency of emergency department visits and ambulance calls. DESIGN: Systematic review. This study was registered in PROSPERO (CRD42022340109). We assessed risk of bias using RoB 2.0, ROBINS-I, and ROBINS-E. DATA SOURCES: We searched the PubMed, Cochrane CENTRAL, and EMBASE databases from their inception until September 22, 2022 for studies comparing patients with and without advanced care planning and reported the frequency of emergency department visits and ambulance calls as outcomes. RESULTS: Eight studies were included. Regarding settings, two studies on patients in nursing homes showed that advanced care planning significantly reduced the frequency of emergency department visits and ambulance calls. However, two studies involving several medical care facilities reported inconclusive results. Regarding patient disease, a study on patients with depression or dementia showed that advanced care planning significantly reduced emergency department visits; in contrast, two studies on patients with severe respiratory diseases and serious illnesses showed no significant reduction. Seven studies showed a high risk of bias. CONCLUSIONS: Advanced care planning may lead to reduced emergency department visits and ambulance calls among nursing home residents and patients with depression or dementia. Further research is warranted to identify the effectiveness of advanced care planning in specific settings and diseases.

Evaluation of enhanced home care support clinics regarding emergency home visits, hospitalization, and end-of-life care: a retrospective cohort study in a city of Japan.

BACKGROUND: To meet the increasing demand for home healthcare in Japan as the population ages, home care support clinics/hospitals (HCSCs) and enhanced HCSCs were introduced in 2006 and 2012, respectively. This study aimed to evaluate whether enhanced HCSCs fulfilled the expected role in home healthcare. METHODS: We conducted a retrospective cohort study using linked medical and long-term care claims data from a municipality in Japan. Participants were ≥ 65 years of age, had newly started regular home visits between July 2014 and March 2018, and used either conventional or enhanced HCSCs. Patients were followed up for one year after they started regular home visits or until the month following the end of the regular home visits if they ended within one year. The outcome measures were (i) emergency home visits at all hours and on nights and holidays at least once, respectively, (ii) hospitalization at least once, and (iii) end-of-life care, which was evaluated based on the place of death and whether a physician was present at the time of in-home death. Multivariable logistic regression analyses were conducted for the outcomes of emergency home visits and hospitalizations. RESULTS: The analysis included 802 patients, including 405 patients in enhanced HCSCs and 397 patients in conventional HCSCs. Enhanced HCSCs had more emergency home visits at all hours than conventional HCSCs (65.7% vs. 49.1%; adjusted odds ratio 1.70, 95% CI [1.26-2.28]), more emergency home visits on nights and holidays (33.6% vs. 16.7%; 2.20 [1.55-3.13]), and fewer hospitalizations (21.5% vs. 32.2%; 0.55 [0.39-0.76]). During the follow-up period, 229 patients (152 patients in enhanced HCSCs and 77 patients in HCSCs) died. Deaths at home were significantly more common in enhanced HCSCs than in conventional HCSCs (80.9% vs. 64.9%; p < .001), and physician-attended deaths among those who died at home were also significantly more common in enhanced HCSCs (99.2% vs. 78.0%; p < .001). CONCLUSIONS: This study confirms that enhanced HCSCs are more likely to be able to handle emergency home visits and end-of-life care at home, which are important medical functions in home healthcare. Further promotion of enhanced HCSCs would be advantageous.

Association between physicians' characteristics and their knowledge, attitudes, and practices regarding advance care planning: a cross-sectional study.

BACKGROUND: Despite physicians' vital role in advance care planning, a limited number of physicians practice it. This study assessed factors associated with physicians' knowledge, attitudes, and practices regarding advance care planning. METHODS: This cross-sectional study used data from an anonymous survey conducted by the Japanese Ministry of Health, Labour and Welfare. Questionnaires were mailed to 4500 physicians in November and December 2022. Data from 1260 respondents were analyzed. RESULTS: Of the respondents, 46.4%, 77.0%, and 82.0% reported good knowledge of advance care planning, agreed with promoting it, and with its provision by medical/care staff, respectively. Male physicians were significantly less likely to support advance care planning (odds ratio: 0.54, 95% confidence interval: 0.35-0.84) or agree to its provision by medical/care staff (odds ratio: 0.47, 95% confidence interval: 0.29-0.78) but significantly more likely to practice it (odds ratio: 1.58, 95% confidence interval: 1.05-2.36). Physicians specialized in surgery or internal/general/palliative medicine were more knowledgeable about advance care planning and more likely to practice it. Physicians working in clinics were significantly less knowledgeable (odds ratio: 0.33, 95% confidence interval: 0.25-0.44) about advance care planning and less likely to support it (odds ratio: 0.37, 95% confidence interval: 0.27-0.50), agree with its provision by medical/care staff (odds ratio: 0.54, 95% confidence interval: 0.39-0.75), or to practice it (odds ratio: 0.16, 95% confidence interval: 0.12-0.22). CONCLUSIONS: Physicians working in clinics had less knowledge of advance care planning, less supportive attitudes, and less likely to practice it. Knowledge, attitudes and practice also varied by gender and specialty. Interventions should target physicians working in clinics.

Impact of COVID-19 on pediatric surgery cancellations: A retrospective study.

BACKGROUND: Prevalence trends and reasons for pediatric surgery cancellation in Japan during the coronavirus disease 2019 (COVID-19) pandemic have not previously been reported. This study aimed to compare the prevalence and reasons for cancellation of pediatric surgeries in Japan before and during the COVID-19 pandemic. METHODS: This single-center retrospective cohort study reviewed the reasons for surgery cancellations scheduled for patients aged <18 years between the prepandemic period (September 2017-December 2019) and the COVID-19 pandemic period (January 2020-April 2022). The cancellation reasons were classified into four major categories: medical, surgical, patient-related, and administrative. RESULTS: Of the 3395 and 3455 surgeries scheduled before and during the COVID-19 pandemic, 305 (9.0%) and 319 (9.2%) surgeries were canceled (p = 0.737), respectively. The proportion of cancellations due to infections or fever in medical reasons decreased from 67.9% to 56.1% (p = 0.003) and that due to patient-related reasons increased from 6.6% to 15.1% (p = 0.001). Further, the proportion of cancellations due to staff shortages in staff administrative reasons increased from 0.3% to 3.1% (p = 0.011). There was no significant difference in the proportion of surgeries canceled due to surgical reasons between the two periods. CONCLUSIONS: The proportion of cancellations due to infections or fever decreased during the COVID-19 pandemic, while that due to staff shortages increased. Infection prevention is an important measure to address the staff shortages. Implementation of national or regional policies and additional strategic interventions may be required to prepare for disasters like the COVID-19 pandemic.

Clinical Features and Mortality of COVID-19-Associated Mucormycosis: A Systematic Review and Meta-Analysis.

The recent increase of COVID-19-associated mucormycosis (CAM) has been commanding global attention. However, basic epidemiologic characteristics have not firmly been established. In this systematic review and meta-analysis, we sought to determine the clinical manifestations, potential risk factors, and outcomes of CAM. Observational studies reporting CAM were searched with PubMed and EMBASE databases in January 2022. We collected data on comorbidities and treatment for COVID-19, and performed a one-group meta-analysis on the frequency of orbital exenteration procedure and mortality of CAM using a random-effect model. Fifty-one observational studies, including a total of 2,312 patients with proven CAM, were identified. Among the 51 studies, 37 were conducted in India, 8 in Egypt, and 6 in other countries. The most common comorbidity was diabetes mellitus (82%). While 57% required oxygenation, 77% received systemic corticosteroids. Among CAM, 97% were rhino-orbital-cerebral (ROCM), and 2.7% were pulmonary mucormycosis. Usual presentations were headache (54%), periorbital swelling/pain (53%), facial swelling/pain (43%), ophthalmoplegia (42%), proptosis (41%), and nasal discharge/congestion (36%). Regarding the outcomes, orbital exenteration was performed in 17% (95% CI: 12-21%, I2 = 83%) of the COVID-19-associated ROCM patients. The mortality of CAM was 29% (95% CI; 22-36%, I2 = 92%). In conclusion, this systematic review and meta-analysis indicated that the most prevalent type of CAM was ROCM, and most CAM patients had diabetes mellitus and received systemic glucocorticoids. Clinicians in the endemic areas should have a high index of suspicion for this invasive fungal complication of COVID-19 when a diabetic patient who received high-dose systemic glucocorticoids developed rhino-orbital symptoms.

Epinephrine dosing interval and neurological outcome in out-of-hospital cardiac arrest.

OBJECTIVE: Current guidelines for cardiopulmonary resuscitation (CPR) recommend that standard-dose epinephrine be administered every 3-5 minutes during cardiac arrest. However, there is a knowledge gap regarding the optimal epinephrine dosing interval. This study aimed to examine the association between epinephrine dosing intervals and outcomes after out-of-hospital cardiac arrest (OHCA). METHODS: This was a nationwide population-based observational study using data from a Japanese government-led registry of OHCA, including patients who experienced OHCA in Japan from 2011 to 2017. We defined the epinephrine dosing interval as the time interval between the first epinephrine administration and return of spontaneous circulation in the prehospital setting, divided by the total number of epinephrine doses. The primary outcome was 1-month neurologically favorable survival. RESULTS: A total of 10,965 patients (mean (SD) age, 75.8 (14.3) years; 59.8% male) were included. The median epinephrine dosing interval was 3.5 minutes (IQR, 2.5-4.5; mean (SD), 3.6 (1.8)). Only approximately half of the patients received epinephrine administration with a standard dosing interval, as recommended in the current CPR guidelines. After multivariable adjustment, compared with the standard dosing interval, neither shorter nor longer epinephrine dosing intervals were associated with neurologically favorable survival after OHCA (Short vs Standard: adjusted OR 0.87 [95%CI 0.66-1.15]; and Long vs Standard: adjusted OR 1.08 [95%CI 0.76-1.55]). Similar associations were observed in propensity score-matched analyses. CONCLUSIONS: The epinephrine dosing interval was not associated with 1-month neurologically favorable survival after OHCA. Our findings do not deny the recommended epinephrine dosing interval in the current CPR guidelines.

Impact of clinical information on CT diagnosis by radiologist and subsequent clinical management by physician in acute abdominal pain.

OBJECTIVE: The impact of clinical information on radiological diagnoses and subsequent clinical management has not been sufficiently investigated. This study aimed to compare diagnostic performance between radiological reports made with and without clinical information and to evaluate differences in the clinical management decisions based on each of these reports. METHODS: We retrospectively reviewed 410 patients who presented with acute abdominal pain and underwent unenhanced (n = 248) or enhanced CT (n = 162). Clinical information including age, sex, current and past history, physical findings, and laboratory tests were collected. Six radiologists independently interpreted CTs that were randomly assigned with or without clinical information, made radiological diagnoses, and scored the diagnostic confidence level. Four general and emergency physicians simulated clinical management (i.e., followed up in the outpatient clinic, hospitalized for conservative therapy, or referred to other departments for invasive therapy) based on reports made with or without the clinical information. Reference standards for the radiological diagnoses and clinical management were defined by an independent expert panel. RESULTS: The radiological diagnoses made with clinical information were more accurate than those made without clinical information (93.7% vs. 87.8%, p = 0.008). Median interpretation time for radiological reporting with clinical information was significantly shorter than that without clinical information (median 122.0 vs. 139.0 s, p < 0.001). Clinical simulation better matched the reference standard for clinical management when radiological diagnoses were made with reference to clinical information (97.3% vs. 87.8%, p < 0.001). CONCLUSION: Access to adequate clinical information enables accurate radiological diagnoses and appropriate subsequent clinical management of patients with acute abdominal pain. KEY POINTS: • Radiological interpretation improved diagnostic accuracy and confidence level when clinical information was provided. • Providing clinical information did not extend the interpretation time required by radiologists. • Radiological interpretation with clinical information led to correct clinical management by physicians.

Is "pain before vomiting" useful?: Diagnostic performance of the classic patient history item in acute appendicitis.

BACKGROUND: In most surgical textbooks, it has been stated that pain almost always precedes vomiting in patients with appendicitis. However, the usefulness of this classic history item, "pain before vomiting", has been investigated in only one study nearly 50 years ago, in which the cause of abdominal pain could not be identified in more than 40% of patients. Accordingly, our objective was to evaluate the performance of pain before vomiting for the diagnosis of acute appendicitis in patients who presented with both acute abdominal pain and vomiting. METHODS: A retrospective chart review of adult outpatients with abdominal pain and vomiting at three acute care hospitals was performed. The reference standard for appendicitis was a CT scan evaluated by two radiologists. Diagnostic performance of pain before vomiting and the value it added to the Alvarado score were evaluated. RESULTS: Among 310 patients, 24 patients were diagnosed with appendicitis. Diagnostic performance of pain before vomiting was a sensitivity of 95.8% (95% confidence interval [CI] 79.8-99.3) and a specificity of 16.6% (95% CI 12.6-21.4). When combined with the Alvarado score, it ruled out appendicitis in an additional 12% (increased from 32% to 44%) of patients without any false negatives. CONCLUSIONS: "Pain before vomiting" is useful for ruling out appendicitis in patients with abdominal pain and vomiting.

Patients' impressions of after-hours house-call services during the COVID-19 pandemic in Japan: a questionnaire-based observational study.

BACKGROUND: Access to healthcare has been strongly affected by the coronavirus disease 2019 (COVID-19) pandemic, which has raised concerns about the increased risk of delays in receiving medical care. This study aimed to assess the patients' impressions of after-hour house-call (AHHC) medical services during the COVID-19 pandemic using a patient questionnaire. METHODS: This was a cross-sectional observational study of anonymized medical record data and internet-based questionnaires from patients who used AHHC medical services from April 2020 to January 2021. We summarized the patients' impressions of AHHC medical services during the COVID-19 pandemic stratified by patient characteristics. The questions of the questionnaire were as follows: (i) Did you use the AHHC medical services because you suspected you had COVID-19 infection? (ii) Do you feel that the use of AHHC medical services has helped prevent transmission of COVID-19? (iii) What action would you have taken in the absence of AHHC medical services? RESULTS: A total of 1802 patients responded to the questionnaire (response rate: 11.3%). First, 700 (40.8%) of the responders indicated that they had used AHHC medical services because of suspicion of COVID-19. Second, most responders (88.8%) felt that AHHC medical services prevented transmission of COVID-19. Third, 774 (43.0%) of the responders considered that they would have visited an emergency department or called an ambulance if AHHC medical services had not been used. Furthermore, 411 (22.8%) of the responders indicated that they would remain at home or wait until working hours if AHHC medical services were not available despite having a condition that required emergency attention. CONCLUSIONS: AHHC medical services may be one of the strategies for those who refrain from seeking healthcare services, thus reducing the risk of delayed hospital visits during emergencies. Furthermore, AHHC medical services may also contribute to preventing transmission of COVID-19 by avoiding contact with other patients in the hospital.

Strain patterns in normal anterior talofibular and calcaneofibular ligaments and after anatomical reconstruction using gracilis tendon grafts: A cadaver study.

BACKGROUND: Inversion ankle sprains, or lateral ankle sprains, often result in symptomatic lateral ankle instability, and some patients need lateral ankle ligament reconstruction to reduce pain, improve function, and prevent subsequent injuries. Although anatomically reconstructed ligaments should behave in a biomechanically normal manner, previous studies have not measured the strain patterns of the anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) after anatomical reconstruction. This study aimed to measure the strain patterns of normal and reconstructed ATFL and CFLs using the miniaturization ligament performance probe (MLPP) system. METHODS: The MLPP was sutured into the ligamentous bands of the ATFLs and CTLs of three freshly frozen cadaveric lower-extremity specimens. Each ankle was manually moved from 15° dorsiflexion to 30° plantar flexion, and a 1.2-N m force was applied to the ankle and subtalar joint complex. RESULTS: The normal and reconstructed ATFLs exhibited maximal strain (100) during supination in three-dimensional motion. Although the normal ATFLs were not strained during pronation, the reconstructed ATFLs demonstrated relative strain values of 16-36. During the axial motion, the normal ATFLs started to gradually tense at 0° plantar flexion, with the strain increasing as the plantar flexion angle increased, to a maximal value (100) at 30° plantar flexion; the reconstructed ATFLs showed similar strain patterns. Further, the normal CFLs exhibited maximal strain (100) during plantar flexion-abduction and relative strain values of 30-52 during dorsiflexion in three-dimensional motion. The reconstructed CFLs exhibited the most strain during dorsiflexion-adduction and demonstrated relative strain values of 29-62 during plantar flexion-abduction. During the axial motion, the normal CFLs started to gradually tense at 20° plantar flexion and 5° dorsiflexion. CONCLUSION: Our results showed that the strain patterns of reconstructed ATFLs and CFLs are not similar to those of normal ATFLs and CFLs.

Three-dimensional analysis of anterior talofibular ligament strain patterns during cadaveric ankle motion using a miniaturized ligament performance probe.

BACKGROUND: Measuring the strain patterns of ligaments at various joint positions informs our understanding of their function. However, few studies have examined the biomechanical properties of ankle ligaments; further, the tensile properties of each ligament, during motion, have not been described. This limitation exists because current biomechanical sensors are too big to insert within the ankle. The present study aimed to validate a novel miniaturized ligament performance probe (MLPP) system for measuring the strain patterns of the anterior talofibular ligament (ATFL) during ankle motion. METHODS: Six fresh-frozen, through-the-knee, lower extremity, cadaveric specimens were used to conduct this study. An MLPP system, comprising a commercially available strain gauge (force probe), amplifier unit, display unit, and logger, was sutured into the midsubstance of the ATFL fibers. To measure tensile forces, a round, metal disk (a "clock", 150 mm in diameter) was affixed to the plantar aspect of each foot. With a 1.2-Nm load applied to the ankle and subtalar joint complex, the ankle was manually moved from 15° dorsiflexion to 30° plantar flexion. The clock was rotated in 30° increments to measure the ATFL strain detected at each endpoint by the miniature force probe. Individual strain data were aligned with the neutral (0) position value; the maximum value was 100. RESULTS: Throughout the motion required to shift from 15° dorsiflexion to 30° plantar flexion, the ATFL tensed near 20° (plantar flexion), and the strain increased as the plantar flexion angle increased. The ATFL was maximally tensioned at the 2 and 3 o'clock (inversion) positions (96.0 ± 5.8 and 96.3 ± 5.7) and declined sharply towards the 7 o'clock position (12.4 ± 16.8). Within the elastic range of the ATFL (the range within which it can return to its original shape and length), the tensile force was proportional to the strain, in all specimens. CONCLUSION: The MLPP system is capable of measuring ATFL strain patterns; thus, this system may be used to effectively determine the relationship between limb position and ATFL ankle ligament strain patterns.

Clinical outcomes of concurrent surgery with weight bearing after modified lasso-loop stitch arthroscopic ankle stabilization.

PURPOSE: To determine the effects of unilateral and bilateral ankle stabilization surgery with or without additional concurrent procedures for other pathologies on return to activity in patients who were allowed unrestricted weight bearing postoperatively. METHODS: Ninety-three athletes underwent 120 ankle stabilization surgeries including 27 that underwent bilateral simultaneous surgery using the all-inside arthroscopy-modified lasso-loop technique and were divided into two groups: arthroscopic ligament repair alone without concurrent procedures (group A) and with simultaneous procedures for other pathologies (group B). Group A was further subdivided into unilateral (group A1) and simultaneous bilateral ankle surgery (group A2), and group B into ankle stabilization surgery with simultaneous procedures not requiring weight bearing postoperatively (Group B1) and with concurrent procedures allowing weight bearing (Group B2). Return to activity postoperatively was assessed by recording the time to walk without any support, jog, and return to full athletic activities. Clinical outcomes were assessed preoperatively and 12 months postoperatively using a subjective clinical score. RESULTS: The average time between surgery and unsupported walk, jog, and return to full athletic activities was 1.6 ± 2.5, 16.9 ± 3.7, and 42.4 ± 19.3 days in group A, 17.2 ± 19.6, 34.5 ± 20.8, and 60.9 ± 22.8 days in group B, 1.7 ± 2.9, 16.1 ± 2.4, and 41.6 ± 18.2 days in group A1, 1.3 ± 0.6, 18.9 ± 5.5, and 44.6 ± 22.5 days in group A2, 25.3 ± 20.2, 43.3 ± 21.1, and 70.7 ± 23.1 days in group B1, and 4.8 ± 11.7, 20.7 ± 11.7, and 45.0 ± 13.7 days in group B2, respectively. These results indicate that the patients in group B2 showed a statistically significant faster time to return to activity than did those restricted from weight bearing. Differences in ankle stabilization alone between patients in groups A1 and A2 as well as groups B2 and A were not statistically significant. Clinical outcomes were similar for patients in groups B2 and A1 versus group A2. CONCLUSION: Time to return to activity and clinical outcomes after ankle stabilization surgery using the modified lasso-loop technique were negatively affected if simultaneous bilateral surgery or simultaneous concurrent procedures were added or if weight bearing was unrestricted. However, a delay in return to athletic activity was observed when ankle stabilization surgery was performed using the modified lasso-loop technique with concurrent procedures that require non-weight bearing postoperatively. LEVEL OF EVIDENCE: Level III.

Changes in the proportion and severity of patients with fever or common cold symptoms utilizing an after-hours house call medical service during the COVID-19 pandemic in Tokyo, Japan: a retrospective cohort study.

BACKGROUND: Trends in the characteristics and disease severity of patients using an after-hours house call (AHHC) medical service changed during the coronavirus disease (COVID-19) pandemic. However, there have been no reports on this issue since the start of the COVID-19 pandemic. This study aimed to investigate patients' tendencies to utilize an AHHC medical service for fever or common cold symptoms during the COVID-19 pandemic. METHODS: This retrospective cohort study compared the characteristics and disease severity of patients with fever or common cold symptoms utilizing an AHHC medical service offered by a single large company between the control period (December 1, 2018 to April 30, 2019) and the COVID-19 pandemic exposure period (December 1, 2019 to April 30, 2020). We also assessed the proportion of these patients in relation to all patients calling the service for any reason. RESULTS: During the control and COVID-19 pandemic exposure periods, a total of 6462 and 10,003 patients consulted the AHHC medical service, respectively. Of these, 5335 (82.6%) and 7423 (74.2%) patients had fever and common cold symptoms, respectively, during the control and COVID-19 pandemic exposure periods (P < 0.001). The corresponding median (interquartile range) ages were 8 (3-11) and 10 (4-33) years, respectively. The distribution of disease severity differed between the groups. The proportions of patients with mild, moderate, and severe illness were 71.1, 28.7, and 0.2% in the control period and 42.3, 56.7, and 0.9% in the COVID-19 pandemic exposure period, respectively (P < 0.001). CONCLUSIONS: During the COVID-19 pandemic, the proportion of patients with fever or common cold symptoms was lower than that in the control period, but disease severity was significantly higher.