Pediatric reference values of NT-proBNP and Galectin-3 based on a French cohort.

BACKGROUND: In pediatric cardiology, the fact that some new biomarkers have assay-specific normal values has to be considered for correct clinical decisions. The current study aimed to provide age-adjusted normative values for NT-proBNP and Galectin-3 using the Abbott immunoassay system from a prospective French pediatric cohort sera collection and to validate our data for NT-proBNP on a second retrospective cohort. METHODS: We analyzed 283 consecutive samples for NT-proBNP and 140 samples for Galectin-3 collected from apparently healthy children (0-18 years) with outpatient treatment at our institution (Hôpital Necker-Enfants malades, Paris, France) during 24 months. RESULTS: For NT-proBNP and Galectin-3, we establish four age partitions, respectively two (<2 years / >2 years) and establish upper reference values and their 90 % CI for each biomarker (Galectin-3 (ng/mL): 56 [44-70] / 26 [23-29]). We evaluated the diagnostic performance of our upper reference values of NT-proBNP on a retrospective cohort (n = 428) with positive predictive value of 0.92. CONCLUSIONS: Using Abbott immunoassay system, we report age-specific reference values for NT-proBNP and for the first time for Galectin-3 in a healthy French pediatric cohort. These data call for larger cohort studies to define more robustly percentiles and diagnostic performance for NT-proBNP.

Histomorphometric parameters of iliac bone in healthy individuals: Systematic review and meta-analysis.

Despite its invasive character, bone biopsy followed by histomorphometry remains the gold standard for diagnosing and classifying many metabolic bone diseases. However, the interpretation of histomorphometric parameters requires comparison with average values obtained from a proper control group, which are only available for some populations, and reference standards still need to be published. Therefore, our objective was to estimate average values for bone histomorphometric parameters overall, by age, gender, and race (White and Black) categories of healthy adult individuals, based on a systematic review and meta-analysis of clinical studies. Relevant studies published in English with available results until December 2020 were identified by PubMed (Medline) search and consulting experts in the field. Out of 447 potentially relevant studies, 37 met the inclusion criteria. Meta-analysis using fixed-effects models was used to pool mean estimates and 95 % confidence intervals (CI) for 16 bone histomorphometry parameters. An age-by-gender trend was observed in most histomorphometry parameters. The mean estimates of bone volume/tissue volume (BV/TV), trabecular thickness (Tb.Th), and trabecular number (Tb.N) decreased. In contrast, trabecular separation (Tb.Sp) increased from the youngest to the oldest age categories in both genders. Osteoblast surface (Ob.S/BS) and osteoclast surface (Oc.S/BS) decreased across all age categories in males. Mineralizing surface (MS/BS) increased from the youngest to the oldest age categories in females, while mineralization lag time (Mlt) increased in both genders. Furthermore, gender and race had a significant effect on several histomorphometry parameters. In conclusion, this meta-analysis provided mean estimates for normal values of histomorphometric parameters that clinicians may use when evaluating bone biopsies in patients. This enables the direct comparison of patients' histomorphometric values with the suitable reference group regarding age, gender, and race.

Identifying abnormal exertional breathlessness in COPD: comparing mMRC and CAT with CPET.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) management is guided by the respiratory symptom burden, assessed using the modified Medical Research Council (mMRC) scale and/or COPD Assessment Test (CAT). RESEARCH QUESTION: What is the ability of mMRC and CAT to detect abnormally high exertional breathlessness on incremental cardiopulmonary cycle exercise testing (CPET) in people with COPD? STUDY DESIGN AND METHODS: Analysis of people aged ≥40 years with post-bronchodilator FEV1/FVC<0.70 and ≥10 smoking pack-years from the Canadian Cohort Obstructive Lung Disease study. Abnormal exertional breathlessness was defined as a breathlessness (Borg 0-10) intensity rating > upper limit of normal (ULN) at the symptom-limited peak of CPET using normative reference equations. RESULTS: We included 318 people with COPD (40% women), age 66.5±9.3 years (mean±SD), FEV1 79.5±19.0%predicted; 26% had abnormally low exercise capacity (V'O2peak

Reliability, reference values and factors related to maximum bite force measured by the Innobyte system in healthy adults with natural dentitions.

OBJECTIVES: We aimed to determine the predictors of maximum bite force (MBF), as measured with the Innobyte system, and to assess the reliability and reference values for MBF in young adults with natural dentitions. METHODS: This cross-sectional test-retest study included 101 dental students with natural dentitions. Participants had their dental occlusion examined and completed three questionnaires: the Temporomandibular disorders Pain Screener, Oral Behavior Checklist, and Jaw Functional Limitation Scale. Body mass index and muscle mass percentage were determined, and handgrip strength was measured with a dynamometer. The MBF was measured with Innobyte, with reliability assessed by the intraclass correlation coefficient, expressing reference values as MBF percentiles. Bivariate tests and multiple linear regression models were used for statistical analysis. RESULTS: The intraclass correlation coefficient for the MBF was 0.90, with 10th to 90th percentiles of 487-876 N for females and 529-1003 N for males. A positive relationship existed between the MBF and male sex, muscle mass percentage, overbite, handgrip strength, and possible sleep/awake bruxism. Stepwise regression showed that overbite, handgrip strength, and possible sleep/awake bruxism had the greatest effect on the MBF, explaining 27% of the variation. CONCLUSIONS: This study provides reference values for MBF when using the Innobyte system and shows excellent reliability. Overbite, general strength, and self-reported bruxism appear to be important predictors of MBF. CLINICAL RELEVANCE: Innobyte is a reliable device that can be used to measure MBF bilaterally. Self-reported bruxism is associated with an 8%-10% increase in MBF.

Reference Ranges and Z-Score Equations for 19 Fetal Cardiac Biometry Structures From 18 to 34 Weeks' Gestation.

OBJECTIVE: To determine equations for calculating the Z-scores of fetal cardiac structures between 18+0 and 34+6 weeks of gestation, create percentile reference tables and curves for the structures, and assess the intra- and inter-observer reproducibility of the measurements. METHODS: A cross-sectional study was conducted involving 340 normal fetuses from singleton pregnancies between 18 and 34 weeks of gestational age (GA). Nineteen cardiac structures were evaluated: diameters of the mitral, tricuspid, aortic, and pulmonary valve annuli; length, diameter, and area of the left and right ventricles; cardiac area and circumference; and diameters of the ascending aorta, aortic isthmus, main pulmonary artery, right pulmonary artery, left pulmonary artery, and ductus arteriosus. Regression analysis was performed to determine the equations for the mean and standard deviation of all structures using GA, biparietal diameter (BPD), and femur length (FL) as independent variables. RESULTS: All equations had high coefficients of determination (R2). The best performance was achieved using the GA (R2 .819-.944), followed by FL (R2 .813-.937) and BPD (R2 .792-.934). The structure that demonstrated the highest R2 was the cardiac circumference and the smallest was the ductus arteriosus. Reference tables of percentiles 1, 5, 10, 50, 90, 95, and 99, and reference curves of Z-scores were created for all 19 cardiac structures, depending on the GA. All measurements demonstrated good and excellent reproducibility with an inter-observer intraclass correlation coefficient (ICC) of 0.774-0.972 and intra-observer ICC of 0.938-0.993. CONCLUSIONS: Equations were produced to calculate Z-scores as well as percentile tables and curves for 19 fetal heart structures. All the measurements demonstrated good reproducibility.

Reference Values for Handgrip Strength, Five Times Sit-to-stand, and Gait Speed in Patients on Hemodialysis.

BACKGROUND AND HYPOTHESIS: Low levels of muscle strength and function predict adverse clinical outcomes in patients on hemodialysis; however, reference values remain lacking. We described reference values for handgrip strength, five times sit-to-stand (STS-5), and 4-m gait speed in a large-scale sample in patients on hemodialysis. METHODS: Baseline data from the SARCopenia trajectories and associations with adverse clinical outcomes in patients on HemoDialysis (SARC-HD) study were analyzed. Muscle strength was evaluated using handgrip strength and the STS-5, whereas physical performance was evaluated using usual 4-m gait speed before a midweek dialysis session. Sex- and age-specific smoothed reference curves for each test at the 3rd, 15th, 50th, 85th, and 97th percentiles were constructed using generalized additive models for location shape and scale. Comparisons between sex and age were also performed. RESULTS: Data from 1004 patients (39% female; 19 to 96 years; 49% ≥ 60 years) were analyzed. Declines in muscle strength and physical performance were observed with advancing age in both sexes. However, among males, muscle strength and performance were similar between 18 and 49 years of age. Males exhibited substantially greater performance in handgrip strength (10.3 kg, 95% confidence interval (CI) 9.1 to 11.4) and 4-m gait speed (-0.10 seconds, 95% CI: -0.14 to -0.05) compared to females. Older patients, independent of sex, exhibited poorer performance on most tests. Lower handgrip strength in the arm with arteriovenous fistula was observed in both sexes (males -2.3 kg, 95% CI: -2.8 to -1.7; and females -2.1 kg, 95% CI: -2.6 to -1.6). CONCLUSION: Reference values obtained in this study may be used in clinical and research settings to identify patients on hemodialysis with low physical function according to sex and age. Future studies should test these reference values as potential predictors of adverse clinical outcomes.

Reference value models for predicting preoperative six-minute walk test in patients scheduled for abdominal and pelvic cancer surgery.

Preoperative assessment of functional capacity with the six-minute walk test (6MWT) allows for estimation of surgical risk and targeted triage to prehabilitation services. Patient with abdominal and pelvic cancers have worse preoperative function compared with the general population. However, six-minute walk distance (6MWD) reference values from cancer patients are unknown, which limits the interpretation of 6MWT in this population. This study aimed to establish an explanatory reference value model for preoperative 6MWD in patients with abdominal or pelvic cancers undergoing elective surgery. Adult patients undergoing surgery for abdominal or pelvic cancers at major international hospitals were included. The 6MWT was assessed before surgery using a standardised protocol. Anthropometric data including age, sex, height, weight and body mass index (BMI) were collected and included in multiple linear regression analysis to model preoperative 6MWD. A total of 742 patients were included. Age, height and BMI were correlated with 6MWD. Six regression models were estimated, including two from the entire cohort, two from the subset of males and two from the subset of females. A sex-neutral model was the most representative, explaining 15% of the variance in 6MWD (6MWD = 761.00-3.00 * Age (years) -2.86 * BMI (kg/m2) - 48.09 * Sex (M1, F2)). The explored regression models, using anthropometric variables, poorly explained the variance between measured and modelled 6MWD, which suggests that these models have no clinical utility in the cancer population. Consideration of additional, non-anthropometric variables may improve regression modelling of preoperative 6MWD in patients in abdominal and pelvic cancers.

Reference values for cerebral and peripheral tissue oximetry in children: A clinical TD-NIRS study.

AIM: Current non-invasive near-infrared spectroscopy (NIRS) tissue oximetry suffers from suboptimal reproducibility over probe repositioning, hindering clinical threshold establishment. Time Domain-NIRS (TD-NIRS) offers higher precision but lacks sufficient paediatric data, preventing effective clinical application. We aimed to establish reference ranges for cerebral and mid-upper arm (MUA) tissue haemodynamics in paediatric subjects using TD-NIRS and explore correlations with auxological variables. METHODS: TD-NIRS measurements were conducted acquiring data from cerebral and MUA regions with the NIRSBOX tissue oximeter. Morphological and clinically relevant information were collected to explore potential correlations with TD-NIRS derived parameters. RESULTS: TD-NIRS assessment was applied in 350 children (8.4 ± 5.0 years). Precision of TD-NIRS was demonstrated with standard deviations of 0.9% (StO2) and 4.2 µM (tHb) for frontotemporal cerebral cortex, and 0.8% (StO2) and 3.7 µM (tHb) for MUA. No user dependency was observed. The trends of values for cerebral and peripheral regions vary differently according to age and auxological parameters. CONCLUSION: This study reports resting-state optical and haemodynamic values for a healthy paediatric population, providing a foundation for future investigations into clinically relevant deviations in these parameters. Furthermore, correlations with anthropometric and demographic values provide valuable insights for a deeper understanding of tissue haemodynamic evolution in childhood.

Reference values of strain-derived myocardial work indices in heart transplant patients.

Aims: Myocardial work (MW) is a relatively novel non-invasive echocardiographic method with increasing fields of application. Normal reference ranges of MW indices in patients who have undergone a heart transplant (HTx) have not been determined yet. The aim of this study was to obtain the reference ranges for 2D echocardiographic indices of MW for adult HTx patients and to compare them with the results of the European Association of Cardiovascular Imaging (EACVI) Normal Reference Ranges for Echocardiography (NORRE) study. Methods and results: All consecutive HTx patients admitted at our institution (University Hospital of Siena, Italy) between September 2019 and May 2022 who underwent endomyocardial biopsy (EMB) were considered. Patients with a history of rejection, a history of coronary artery vasculopathy, either acute cellular rejection or acute antibody-mediated rejection at EMB, and donor-specific antibodies were excluded. MW retrospectively performed for the included patients was retrieved, and the results were compared with those from the EACVI NORRE study. Out of 176 HTx patients who underwent EMB, 94 patients were excluded. The study population consisted of 82 HTx patients [68.3% male, median age 53 (46-62) years]. The median duration from HTx was 5 (2-22) months. The main MW indices such as global work efficiency (GWE, 84 ± 8%), global work index (GWI, 1447 ± 409 mmHg%), global constructive work (GCW, 2067 ± 423 mmHg%), and global wasted work [GWW, 310 (217-499) mmHg%] did not differ according to gender. Each of these indices significantly differed from those reported in the EACVI NORRE study (P-value <0.001), with lower GWI, GCW, and GWE and higher GWW values in the HTx population. Conclusion: This study provides reference ranges for MW indices in an adult HTx population free from transplant-related complications which proved to be different from those previously reported in healthy volunteers.

Lone Giant Atrium as a Variant of Atrial Cardiomyopathy: A Cardiovascular Magnetic Resonance Imaging Case Series.

Advances in cardiovascular imaging have expanded the scope and precision of rare diagnoses. Handling a patient with a giant left atrium, we focused on the existence and associated factors of "lone giant (left or right) atria" in our clinical setting. The aim of the current study was to establish reasonable cut-off values for the diagnosis of "giant atrium". Our analysis utilised echocardiography and cardiovascular magnetic resonance (CMR) imaging databases, with the original data re-assessed to ensure consistency and comparability. Four patients met the search criteria, with two cases requiring CMR to confirm the diagnosis of "giant atrium", correcting the initial echocardiographic assessment. Both echocardiography and CMR excel in the assessment of atrial anatomy, although the superior image quality and multiplanar capabilities of CMR support its preference. In assessing the atrial size, the use of 3D volumetric measurements should replace traditional biplane methods due to the complex anatomy of the atrium. We propose the use of an indexed volume threshold (>120 mL/m2) rather than simple diameter measurements for the diagnosis of "giant atria". Structural atrial abnormalities appear to correlate with an increased risk of atrial arrhythmias, while potential serious complications such as thromboembolism or compression symptoms require further observation in larger patient cohorts to establish definitive risks.

Preliminary Normative Reference Values of Validated FEES Scales in Healthy Young Adults.

OBJECTIVES: Limited normative reference data are available for validated outcomes of flexible endoscopic evaluation of swallowing (FEES). We aimed to examine healthy swallowing via FEES in community-dwelling healthy adults to derive a preliminary reference dataset of normative validated FEES outcomes to guide clinical interpretation and diagnostic decision-making. METHODS: Adults with no history of dysphagia-related disease underwent simultaneous videofluoroscopy and FEES imaging using a standardized 11-item bolus protocol. Trained raters performed duplicate, independent, blinded ratings of the New Zealand Secretion Scale (NZSS), Penetration-Aspiration Scale (PAS), and Dynamic Imaging Grade of Swallowing Toxicity-FEES (DIGEST-FEES) validated scales. Descriptive statistics were performed at the bolus (PAS) and participant level (NZSS, DIGEST-FEES). RESULTS: 361 swallows from 33 community-dwelling adults (36.6 ± 14.7 years old) were analyzed. In rank order, distribution profiles were: (1) NZSS: 95% normal (NZSS = 0), 5% abnormal (NZSS = 4); (2) Worst PAS: 73% safe (PAS 1-2, n = 24), 21% penetration above the true vocal folds (PAS 3, n = 7), 6% deep penetration to the true vocal folds (PAS = 5, n = 2); (3) DIGEST-FEES Safety Grades: 91% Grade 0 (normal, n = 30), 9% Grade 1 (mild impairment, n = 3); (4) DIGEST-FEES Efficiency Grades: 73% Grade 0 (normal, n = 24), 24% Grade 1 (mild impairment, n = 8), 3% Grade 2 (moderate impairment, n = 1). CONCLUSION: This preliminary healthy FEES dataset highlights variation in swallowing safety and efficiency and suggests careful interpretation of FEES outcomes to avoid over-pathologizing impairment. Future studies are warranted to obtain additional normative data in diverse populations to further understand normal variation in FEES outcomes to guide clinically meaningful diagnostic cut-points. LEVEL OF EVIDENCE: Level 3 Laryngoscope, 2024.

Compatibility of the global lung function 2012 spirometry reference values in children, adolescents and young adults: a systematic review.

INTRODUCTION: The Global Lung Function Initiative (GLI 2012) has published multiethnic spirometry reference values. To identify studies that evaluated the compatibility (applicability, validity, representativeness, agreement and/or adequacy) of the reference equations proposed by the GLI 2012 for spirometry tests in different populations. METHODS: Systematic searches were carried out on the PubMed, LILACS (Latin American and Caribbean Health Sciences Literature), Scopus, Web of Science and Google Scholar databases. Cross-sectional observational studies published between 2012 and 2013 onwards that evaluated the compatibility of the GLI 2012 in children, adolescents and young adults (3-20 years old) were included. The references were manually searched and the Joanna Briggs Institute Critical Appraisal Checklist for Cross-Sectional Analytical Studies was applied to assess the methodological quality of the studies included. RESULTS: All of the 5632 studies identified were classified as low risk of bias, but only 21 were deemed eligible for inclusion. Of these, 8 reported satisfactory GLI 2012 compatibility for their populations (Argentina, Spain, Columbia, Djibouti, Norway, Poland, Jordan and Zimbabwe), 5 cautious applicability, and the remaining 8 considered the equation unsatisfactory, since it over or underestimated spirometric parameters. CONCLUSION: The GLI 2012 equations are not applicable to all populations and must be tested before being adopted.

Recalibrated FRIEND equation for peak oxygen pulse is accurate in endurance athletes: the NOODLE study.

Peak oxygen pulse (O2Ppeak) is an important index of cardiorespiratory fitness (CRF). The FRIEND database is a global source of reference values for CRF. However, no reference equation is tailored for endurance athletes (EA) to predict O2Ppeak. Here, we adjusted the well-established FRIEND equation for O2Ppeak to the characteristics of the EA population. 32 (34.0%) female EA and 62 (66.0%) male well-trained EA underwent maximal cardiopulmonary exercise test on a treadmill. V̇O2max was 4.5 ± 0.5 L min-1 in males and 3.1 ± 0.4 L min-1 in females. O2Ppeak was 23.6 ± 2.8 mL beat-1 and 16.4 ± 2.0 mL beat-1 for males and females, respectively. Firstly, we externally validated the original FRIEND equation. Secondly, using multiple linear regression, we adjusted the FRIEND equation for O2Ppeak to the population of EA. The original FRIEND equation underestimated O2Ppeak for 2.9 ± 2.9 mL beat-1 (P < .001) in males and 2.2 ± 2.1 mL beat-1 (P < .001) in females. The updated equation was 1.36 + 1.07 (23.2 · 0.09 · age - 6.6 [if female]). The new equation explained 62% of the variance and significantly predicted O2Ppeak (R2 = 0.62, ß = 0.78, P < .001). The error of the EA-adjusted model was 0.1 ± 2.9 mL beat-1 (P = .82) and 0.2 ± 2.1 mL beat-1 (P = .65) for males and females respectively. Recalibration of the original FRIEND equation significantly enhances its accuracy among EA. The error of the EA-adjusted model was negligible. A new recalibrated equation should be used to predict O2Ppeak in the population of EA.

Pancreatic ultrasound: An update of measurements, reference values, and variations of the pancreas.

Reliable and reproducible measurement methods have been established, and reference values are used in almost all scientific disciplines. Knowledge of reference values is crucial to distinguish physiological from pathological processes and, therefore, subsequently, for the clinical management of patients. Image storage and documentation of measurements and normal findings should be part of quality assurance in imaging. This paper aims to review the published literature and provide current knowledge of sonographic measurements and reference values of the pancreas. Moreover, the role of clinical influencing factors such as age, gender, constitution, and ethnicity is also analyzed.

Therapeutic drug monitoring in Parkinson's disease.

A patient-tailored therapy of the heterogeneous, neuropsychiatric disorder of Parkinson's disease (PD) aims to improve dopamine sensitive motor symptoms and associated non-motor features. A repeated, individual adaptation of dopamine substituting compounds is required throughout the disease course due to the progress of neurodegeneration. Therapeutic drug monitoring of dopamine substituting drugs may be an essential tool to optimize drug applications. We suggest plasma determination of levodopa as an initial step. The complex pharmacology of levodopa is influenced by its short elimination half-life and the gastric emptying velocity. Both considerably contribute to the observed variability of plasma concentrations of levodopa and its metabolite 3-O-methyldopa. These amino acids compete with other aromatic amino acids as well as branched chain amino acids on the limited transport capacity in the gastrointestinal tract and the blood brain barrier. However, not much is known about plasma concentrations of levodopa and other drugs/drug combinations in PD. Some examples may illustrate this lack of knowledge: Levodopa measurements may allow further insights in the phenomenon of inappropriate levodopa response. They may result from missing compliance, interactions e.g. with treatments for other mainly age-related disorders, like hypertension, diabetes, hyperlipidaemia, rheumatism or by patients themselves independently taken herbal medicines. Indeed, uncontrolled combination of compounds for accompanying disorders as given above with PD drugs might increase the risk of side effects. Determination of other drugs used to treat PD in plasma such as dopamine receptor agonists, amantadine and inhibitors of catechol-O-methyltransferase or monoamine oxidase B may refine and improve the value of calculations of levodopa equivalents. How COMT-Is change levodopa plasma concentrations? How other dopaminergic and non-dopaminergic drugs influence levodopa levels? Also, delivery of drugs as well as single and repeated dosing and continuous levodopa administrations with a possible accumulation of levodopa, pharmacokinetic behaviour of generic and branded compounds appear to have a marked influence on efficacy of drug treatment and side effect profile. Their increase over time may reflect progression of PD to a certain degree. Therapeutic drug monitoring in PD is considered to improve the therapeutic efficacy in the course of this devastating neurologic disorder and therefore is able to contribute to the patients' precision medicine. State-of-the-art clinical studies are urgently needed to demonstrate the usefulness of TDM for optimizing the treatment of PD.

Force control of pinch grip: Normative data of a holistic evaluation.

BACKGROUND: Pulp pinch (PP) is a vital hand movement involving muscle strength and sensory integration. Previous research has primarily focused on Maximal Voluntary Contraction, but PP encompasses broader parameters. PURPOSE: This study aims to establish normative data for a comprehensive evaluation of thumb and index force control during PP, including endurance, precision, accuracy in unilateral PP, and force coordination in bilateral PP. STUDY DESIGN: A cross-sectional study. METHODS: Three hundred and twenty eight healthy Italian cis-gender participants (169 females, 159 males) were enrolled in a multiparametric force control evaluation of pinch grip, consisting in: sustained contraction (SC: ability to maintain a stable contraction at 40% MVC, measured as the time until exhaustion), dynamic contraction (DC: the ability to modulate precisely and accurately force output to follow a dynamic force trace), bimanual strength coordination (BSC: the ability to coordinate in-phase bimanual forces at different combined magnitudes) tasks. The sample was divided per sex and stratified in five age groups taking into account hand dominance. Differences in tasks' results between age, sex and hand-dominance were analysed. RESULTS: Endurance (SC) was similar between younger and older adults (η2 =0.047 (Females) and η2 < 0.007 (Males)). Older adults exhibited lower precision (DC) and coordination (BSC) compared to young adults in both sexes (η2 >0.16). Females demonstrated greater endurance (SC) but lower precision and coordination (BSC) compared to males (0.01 <η2 <0.1). No hand dominance effect emerged in SC and DC. CONCLUSIONS: Force accuracy and precision to modulate pinch force to perform a visual feedback force-matching task (DC) and force coordination between hands (BSC) worsen at increasing age. Hand dominance did not influence either endurance or precision of pinch grip in visual-feedback guided task.

Internal blood loss in fatal liver lacerations - determining lethality from relative blood loss.

Certificates of medical evidence are often used to aid the court in assessing the cause and severity of a victim's injuries. In cases with significant blood loss, the question whether the bleeding itself was life-threatening sometimes arises. To answer this, the volume classification of hypovolemic shock described in ATLS® is commonly used as an aid, where a relative blood loss > 30% is considered life-threatening. In a recent study of deaths due to internal haemorrhage, many cases had a relative blood loss < 30%. However, many included cases had injuries which could presumably cause deaths via other mechanisms, making the interpretation uncertain. To resolve remaining ambiguity, we studied whether deaths due to isolated liver lacerations had a relative blood loss < 30%, a cause of death where the mechanism of death is presumably exsanguination only. Using the National Board of Forensic Medicine autopsy database, we identified all adult decedents, who had undergone a medico-legal autopsy 2001-2021 (n = 105 952), where liver laceration was registered as the underlying cause of death (n = 102). Cases where death resulted from a combination of also other injuries (n = 79), and cases that had received hospital care, were excluded (n = 4), leaving 19 cases. The proportion of internal haemorrhage to calculated total blood volume in these fatal pure exsanguinations ranged from 12 to 52%, with 63% of cases having a proportion < 30%. Our results lend further support to the claim that the volume classification of hypovolemic shock described in ATLS® is inappropriate for assessing the degree of life-threatening haemorrhage in medico-legal cases.

Validation of VO2max Prediction Using International Formulae for Young Saudi Men.

Objectives: In this study, we aimed to assess the maximal oxygen uptake (VO2max) of young, healthy, non-athletic Saudi men using maximum graded exercise with instant breath-by-breath analysis and to compare this value to the predicted VO2max by international formulae. Methods: In this cross-sectional study, 88 young non-athletic normal-weight Saudi subjects were recruited from Eastern Province of Saudi Arabia with mean age (21.3 ± 1.5 years), weight: (64.7 ± 7.5 kg), height: (172.3 ± 6.1 cm) and body mass index: (21.8 ± 2.1). All subjects were interviewed and examined for eligibility, after which they performed maximum graded exercise testing on a treadmill to obtain VO2max. The predicted VO2max was also generated using the following formulae (Edvardsen, Fairbarns, FRIENDS, Hansen, and Jones). Results: The mean measured VO2max was 41.9 ± 7.2 ml/kg/min. While the predicted VO2max using the formulae were: Edvardsen = 66.8 ± 7.9, Fairbarns = 64.1 ± 4.7, FRIENDS = 53.5 ± 2.2, Hansen = 42.8 ± 0.54, and Jones = 50.9 ± 5.1 ml/kg/min. There was a significant difference between all the predicted VO2max and the measured one using the paired t-test (P < 0.001), except for the Hansen's predicted value (P = 0.212). The effect size index (Cohen's d) for the comparison of Hansen's VO2max and measured VO2max was trivial and equal to 0.13. The Bland-Altman test showed good agreement between the measured and Hansen's predicted VO2max. Conclusion: This study demonstrated the mean VO2max value of young, healthy, and non-athletic Saudi men. This value was lower than Western values, which might be due to low physical activity or racial differences. Most international formulae overestimate the VO2max in this population, except for the Hansen equation. Therefore, Hansen's predicted VO2max might be the best available reference value for the diagnosis and prognosis of young Saudi individuals undergoing maximum exercise testing.

Lower-Quarter Y-Balance Test Differs by Age: Younger Athletes May Not Be Generalized to High School-Aged Counterparts.

Background: Given rising youth sport participation, 8 to 10-year-olds increasingly display comparable lower-extremity injury incidence to 11 to 17-year-olds and require effective return to sport criteria. One such criterion which quantifies dynamic stability is the Y-Balance Test (YBT), though it has not been validated in children under age 11. Hypothesis/Purpose: The purpose of this study was to examine the performance of 8 to 10-year-old patients on the YBT after lower-extremity injury and determine how these results compare to larger samples of age-grouped athletes within the validated 11 to 17-year-old range. It was hypothesized that 8 to 10-year-olds would display different normalized YBT distances compared to 11 to 17-year-olds. Study Design: Cross-sectional Study. Methods: Patients (N=1093) aged 8 to 17 who presented to a pediatric sports medicine practice with a lower-extremity injury and completed the YBT between December 2015-May 2021 were included. Anterior, posteromedial, and posterolateral YBT scores were collected at return-to-sport for affected and unaffected limbs. Scores were normalized to limb length, and composite scores were created. Between-limb differences were calculated in groups of ages 8-10, 11-12, 13-14, and 15-17. Groups were also evaluated for differences by sex. Results: A rise in performance was observed in unaffected limb anterior reach from ages 8 to 10 years to 11 to 12 years followed by a subsequent significant decrease at older ages (p<0.001). Affected limb anterior reach differed between the youngest group and two oldest groups (p=0.004). Anterior and composite difference were significantly different between the oldest three groups (p=0.014 anterior; p=0.024 composite). No differences were observed between sexes in 8 to 10-year-olds, though 11 to 12-year-old females reached further during all eight distances. In the older three groups, males generally displayed greater between-limb differences. Conclusion: YBT scores, specifically anterior reach, demonstrated inconsistency by age and sex across a large adolescent cohort. Existing return-to-sport standards should not be used with younger athletes, and individual validation is required. Level of Evidence: Level III.

Maximal respiratory pressure after COVID-19 compared with reference material in healthy adults: A prospective cohort study (The SECURe study).

After COVID-19 long term respiratory symptoms and reduced lung function including maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) have been reported. However, no studies have looked at MIP and MEP in all disease groups and the reference materials collection methods differ substantially. We aimed to determine MIP and MEP in individuals after COVID-19 infection with different disease severity using reference material of healthy control group obtained using the same standardized method. Patients with COVID-19 were included March 2020-March 2021 at Rigshospitalet, Denmark. MIP and MEP were measured using microRPM. Predicted MIP and MEP were calculated using reference material obtained from 298 healthy adults aged 18-97 years using the same method. In SECURe, 145 participants were measured median 5 months after COVID-19 diagnosis and of these 16% had reduced MIP and/or MEP. There was reduced spirometry and total lung capacity, but not reduced diffusion capacity in those with abnormal MIP and/or MEP compared with normal MIP and MEP. Of those with reduced MIP and/or MEP at 5 months, 80% still had reduced MIP and/or MEP at 12 months follow-up. In conclusion, few have reduced MIP and/or MEP 5 months after COVID-19 and little improvement was seen over time.