Anthropometric approximation of body weight in unresponsive stroke patients

Very low-calorie ketogenic diet (VLCKD): a therapeutic nutritional tool for acne?

BACKGROUND

Acne, a chronic inflammatory disease impacting the pilosebaceous unit, is influenced significantly by inflammation and oxidative stress, and is commonly associated with obesity. Similarly, obesity is also associated with increased inflammation and oxidation. The role of diet in acne remains inconclusive, but the very low-calorie ketogenic diet (VLCKD), known for weight loss and generating anti-inflammatory ketone bodies, presents promising potential. Despite this, the effects of VLCKD on acne remain underexplored. This study aimed to investigate the efficacy of a 45-day active phase of VLCKD in reducing the clinical severity of acne in young women with treatment-naïve moderate acne and grade I obesity.

METHODS

Thirty-one women with treatment-naïve moderate acne, grade I obesity (BMI 30.03-34.65 kg/m2), aged 18-30 years, meeting inclusion/exclusion criteria, and consenting to adhere to VLCKD were recruited. Baseline and post-intervention assessments included anthropometric measurements, body composition, phase angle (PhA), trimethylamine N-oxide (TMAO) levels, and reactive oxygen metabolite derivatives (dROMs) as markers of inflammation, dysbiosis, and oxidative stress, respectively. A comprehensive dermatological examination, incorporating the Global Acne Grading System (GAGS) and the Dermatology Life Quality Index (DLQI), was conducted for all women.

RESULTS

VLCKD resulted in general improvements in anthropometric and body composition parameters. Significantly, there were significant reductions in both the GAGS score (Δ%: - 31.46 ± 9.53, p < 0.001) and the DLQI score (Δ%: - 45.44 ± 24.02, p < 0.001) after the intervention. These improvements coincided with significant decreases in TMAO (p < 0.001) and dROMs (p < 0.001) levels and a significant increase in PhA (Δ%: + 8.60 ± 7.40, p < 0.001). Changes in the GAGS score positively correlated with changes in dROMs (p < 0.001) and negatively with PhA (p < 0.001) even after adjusting for Δ% FM. Changes in the DLQI score positively correlated with changes in dROMs (p < 0.001) and negatively with PhA (p < 0.001) even after adjustment for Δ% FM.

CONCLUSION

Given the side effects of drugs used for acne, there is an increasing need for safe, tolerable, and low-cost treatments that can be used for acne disease. The 45-day active phase of VLCKD demonstrated notable improvements in acne severity, and these improvements seemed to be attributable to the known antioxidant and anti-inflammatory effects of VLCKD.

Automated Patient Registration in Magnetic Resonance Imaging Using Deep Learning-Based Height and Weight Estimation with 3D Camera: A Feasibility Study

RATIONALE AND OBJECTIVES

Accurate and efficient estimation of patient height and weight is crucial to ensure patient safety and optimize the quality of magnetic resonance imaging (MRI) procedures. Several height and weight estimation methods have been proposed for use in adult patient management, but none is widely established. Estimation by the medical technologists for radiology (MTR) based on personal experience remains to be the most common method. This study aimed to compare a novel deep learning (DL)-based 3-dimensional (3D) camera estimation method to MTR staff in terms of estimation accuracy.

METHODS

A retrospective study was conducted to compare the accuracy of height and weight estimation with a DL-based 3D camera algorithm to the accuracy of height and weight estimation by the MTR. Depth images of the patients were captured during the regular imaging workflow on a low field 0.55 T MRI scanner (MAGNETOM Free.Max, Siemens Healthineers, Erlangen, Germany) and then processed retrospectively. Depth images of a total of 161 patients were used to validate the accuracy of the height and weight estimation algorithm. The accuracy of each estimation method was evaluated by computing the proportions of the estimates within 5% and 15% of actual height (PH05, PH15) and within 10% and 20% of actual weight (PW10, PW20). An acceptable accuracy for height estimation was predetermined to be PH05 = 95% and PH15 = 99% and an acceptable accuracy for weight estimation was predetermined to be PW10 = 70% and PW20 = 95%. The bias in height and weight estimation was measured by the mean absolute percentage error (MAPE).

RESULTS

The retrospective study included 161 adult patients. For 148/161 patients complying with inclusion criteria, DL-based 3D camera algorithm outperformed the MTR in estimating the patient's height and weight in term of accuracy (3D camera: PH05 =98.6%, PH15 =100%, PW10 =85.1%, PW20 =95.9%; MTR: PH05 =92.5%, PH15 =100%, PW10 =75.0%, PW20 =93.2%). MTR had a slightly higher bias in their estimates compared to the DL-based 3D camera algorithm (3D camera: MAPE height=1.8%, MAPE weight=5.6%, MTR: MAPE height=2.2%, MAPE weight=7.5%) CONCLUSION: This study has demonstrated that the estimation of the patient's height and weight by a DL-based 3D camera algorithm is accurate and robust. It has the potential to complement the regular MRI workflows, by providing further automation during patient registration.

Very low-calorie ketogenic diet (VLCKD) in the management of hidradenitis suppurativa (Acne Inversa): an effective and safe tool for improvement of the clinical severity of disease. Results of a pilot study

BACKGROUND

Hidradenitis suppurativa (HS), an inflammatory-based dermatological condition often associated with obesity, poses significant challenges in management. The very low-calorie ketogenic diet (VLCKD) has shown efficacy in addressing obesity, related metabolic disorders, and reducing chronic inflammation. However, its effects on HS remain underexplored. In this prospective pilot study, we aimed to investigate the impact of a 28-day active phase of VLCKD on HS in a sample of treatment-naive women with HS and excess weight.

METHODS

Twelve women with HS and overweight or obesity (BMI 27.03 to 50.14 kg/m2), aged 21 to 54 years, meeting inclusion/exclusion criteria and agreeing to adhere to VLCKD, were included. Baseline lifestyle habits were assessed. The Sartorius score was used to evaluate the clinical severity of HS. Anthropometric parameters (waist circumference, weight, height, and body mass index), body composition via bioelectrical impedance analysis, levels of trimethylamine N-oxide (TMAO), oxidized low-density lipoprotein (oxLDL), and derivatives of reactive oxygen metabolites (dROMs) were assessed at baseline and after 28 days of the active phase of VLCKD.

RESULTS

VLCKD led to general improvements in anthropometric parameters and body composition. Notably, a significant reduction in the Sartorius score was observed after the intervention (Δ%: - 24.37 ± 16.64, p < 0.001). This reduction coincided with significant decreases in TMAO (p < 0.001), dROMs (p = 0.001), and oxLDL (p < 0.001) levels. Changes in the Sartorius score exhibited positive correlations with changes in TMAO (p < 0.001), dROMs (p < 0.001), and oxLDL (p = 0.002).

CONCLUSION

The 28-day active phase of VLCKD demonstrated notable improvements in HS severity and associated metabolic markers, highlighting the potential utility of VLCKD in managing HS and its association with metabolic derangements in women with overweight or obesity.

The accuracy of total body weight estimation in adults - A systematic review and meta-analysis

BACKGROUND

Weight estimation is required in adult patients when weight-based medication must be administered during emergency care, as measuring weight is often impossible. Inaccurate estimations may lead to inaccurate drug doses, which may cause patient harm. Little is known about the relative accuracy of different methods of weight estimation that could be used during resuscitative care. The aim of this study was to evaluate the performance and suitability of existing weight estimation methods for use in adult emergency care.

METHODS

A systematic literature search was performed for suitable articles that studied the accuracy of weight estimation systems in adults. The study characteristics, the quality of the studies, the weight estimation methods evaluated, the accuracy data, and any information on the ease-of-use of the method were extracted and evaluated.

RESULTS

A total of 95 studies were included, in which 27 different methods of total body weight estimation were described, with 42 studies included in the meta-analysis. The most accurate methods, determined from the pooled estimates of accuracy (the percentage of estimates within 10% of true weight, with 95% confidence intervals) were 3-D camera estimates (88.8% (85.8 to 91.8%)), patient self-estimates (88.7% (87.7 to 89.7%)), the Lorenz method (77.5% (76.4 to 78.6%)) and family estimates (75.0% (71.5 to 78.6%)). However, no method was without significant potential limitations to use during emergency care.

CONCLUSION

Patient self-estimations of weight were generally very accurate and should be the method of choice during emergency care, when possible. However, since alternative estimation methods must be available when confused, or otherwise incapacitated, patients are unable to provide an estimate, alternative strategies of weight estimation should also be available.

Proportion of Hidden Vertebral Fractures Among Egyptian Males With Fragility Hip Fractures in the Emergency Room of Ain Shams University Hospitals

Background Fragility fractures are linked to significant costs for society as well as significant pain and suffering, disability, and even death. It is well-recognized that osteoporosis-related fragility fractures raise the risk of subsequent fragility fractures. One of the most frequent osteoporotic fractures brought on by low bone mineral density and other risk factors is vertebral fractures. Considering that most vertebral fractures are asymptomatic and not clinically identified, proactive screening could stop additional impairment. Objective The current study aims to determine the prevalence and risk factors of hidden vertebral fractures in Egyptian males who have fragility hip fractures. Patients and methods A cross-sectional case-control study examining the correlation of risk factors between cases (fragility hip fracture and vertebral fractures) and a control group (fragility hip fracture without vertebral fracture) was carried out from September 2020 to September 2021 on patients visiting the orthopedic emergency department of a university hospital in Cairo, Egypt. Males who presented to the emergency room (ER) with fragility hip fractures and were 40 years of age or older met our inclusion criteria. For every patient who presented with a fragility hip fracture, standard lateral and anteroposterior radiographs of the dorso-lumbar spine were taken. Results A total of 43,935 patients visited the orthopedic emergency room (ER) throughout the study period; 13,034 of those patients were men, accounting for 29.7% of all orthopedic ER visits. Our inclusion criteria for fragility hip fractures were met by 132 male participants. The screening lumbosacral plain X-rays identified 27 (20.5%) of the 132 patients as having concomitant vertebral fractures in addition to the fragility hip fractures. Concomitant hidden vertebral fractures among Egyptian males with other fragility fractures, particularly fragility hip fractures, are predicted by the number of co-morbid diseases, hypertension, and continuous use of steroids and anti-epileptics. Conclusion Most fragility fractures are avoidable. Because one fragility fracture increases the likelihood of others, early detection is crucial. To prevent complications and mortality, it is important to identify and manage individuals who have a fragility hip fracture as they frequently have concurrent hidden vertebral fractures. Predictive risk factors for fragility vertebral fractures include hypertension, the number of concomitant illnesses, and chronic drugs (anti-epileptics and steroids).

Proportion and Risk Factors of Silent Vertebral Fractures Among Egyptian Females With Fragility Hip Fracture Presenting to the Emergency Room of Ain Shams University Hospitals

Background Fragility fractures caused by osteoporosis are known to increase the risk of further fragility fractures. Also, several factors have been associated with an increasing risk of fracture in postmenopausal women with osteoporosis, as prior fracture, advancing age, low bone mineral density (BMD), greater risk or history of falls certain, pharmacologic therapies such as glucocorticoids, and medical conditions increase the risk of secondary osteoporosis and related fractures through their direct impact on bone density or structure. Menstrual history including age at menarche menopause and a history of amenorrhea is documented as a predicting osteoporotic fracture. Objective The aim of the current study is to find the proportion of hidden vertebral fractures among Egyptian females with fragility hip fracture. Patients and methods A cross-sectional study was conducted on patients who presented to the orthopedic emergency room (ER) of Ain Shams University Hospitals in Cairo, Egypt, from September 2020 to September 2021. Our inclusion criteria include females aged 40 years or older, who presented to the ER with fragility hip fractures. A simple random sample of females fulfilling our inclusion criteria for osteoporotic hip fracture was thoroughly investigated. Conventional lateral and anteroposterior radiographs of the dorsolumbar spine were obtained excluding those with high-impact fractures or pathological fractures. Results During the study period, a total of 43,935 persons presented to the orthopedic ER, of whom 30,901 were females, comprising 70.03% of total orthopedic ER visits. A sample of 150 females met our inclusion criteria. Results showed that 16 of our 150 cases had concomitant vertebral fracture, meaning that 10.7% of cases had hidden vertebral fracture at the time of osteoporotic hip fracture, as diagnosed by the screening lumbosacral plain X-rays. Older age at menarche, younger age at menopause, and amenorrhea are shown to be risk factors for hidden vertebral fracture in Egyptian females. Conclusion Osteoporosis is a complex and costly disease. Osteoporotic fractures may be largely preventable, as environmental factors are open to intervention, and effective pharmacological agents are available. Concomitant hidden vertebral fracture is prevalent among females with osteoporotic hip fractures, and those who had later menarche, earlier menopause, and menstrual irregularities have a higher incidence of developing associated vertebral fracture, which warrants identification and management to evade complications and mortality.

Development and validation of a length- and habitus-based method of total body weight estimation in adults

BACKGROUND

Erroneous weight estimation during the management of emergency presentations in adults may contribute to patient harm and poor outcomes. Patients can often not be weighed during emergencies and a weight estimation is required to facilitate weight-based therapies. Many existing methods of weight estimation are either unacceptably inaccurate or very difficult to use during the provision of emergency care.

METHODS

The weight estimation system developed in this study was based on and modified from the PAWPER XL-MAC method, a pediatric weight estimation system that uses recumbent length and mid-arm circumference (MAC) to predict total body weight. This model was validated in the 2015-2018 National Health and Nutrition Examination Survey (NHANES) datasets. The primary outcome measure was to achieve >95% of estimations within 20% of measured weight (P20 > 95%).

RESULTS

The modified PAWPER XL-MAC model achieved a P20 of 96.0% and a P10 of 71.3% in the validation dataset (N = 11,520). This accuracy (P20 > 95%) was maintained in both sexes, all ages, all ethnic groups, all lengths and in all habitus-types, except for the subgroup of severely obese individuals.

CONCLUSIONS

The modified PAWPER XL-MAC model proved to be a very accurate method of weight estimation. It is more accurate than most other published reports of existing methods of weight estimation, except for patients' own estimations. It therefore could have a role in facilitating emergency drug dose calculations, if prospective studies bear out the accuracy found in this study.

Seeing under the cover with a 3D U-Net: point cloud-based weight estimation of covered patients

PURPOSE

Body weight is a crucial parameter for patient-specific treatments, particularly in the context of proper drug dosage. Contactless weight estimation from visual sensor data constitutes a promising approach to overcome challenges arising in emergency situations. Machine learning-based methods have recently been shown to perform accurate weight estimation from point cloud data. The proposed methods, however, are designed for controlled conditions in terms of visibility and position of the patient, which limits their practical applicability. In this work, we aim to decouple accurate weight estimation from such specific conditions by predicting the weight of covered patients from voxelized point cloud data.

METHODS

We propose a novel deep learning framework, which comprises two 3D CNN modules solving the given task in two separate steps. First, we train a 3D U-Net to virtually uncover the patient, i.e. to predict the patient's volumetric surface without a cover. Second, the patient's weight is predicted from this 3D volume by means of a 3D CNN architecture, which we optimized for weight regression.

RESULTS

We evaluate our approach on a lying pose dataset (SLP) under two different cover conditions. The proposed framework considerably improves on the baseline model by up to [Formula: see text] and reduces the gap between the accuracy of weight estimates for covered and uncovered patients by up to [Formula: see text].

CONCLUSION

We present a novel pipeline to estimate the weight of patients, which are covered by a blanket. Our approach relaxes the specific conditions that were required for accurate weight estimates by previous contactless methods and thus constitutes an important step towards fully automatic weight estimation in clinical practice.

Comparison of adult weight estimation methods for use during emergency medical care

OBJECTIVE

Many emergency drug and fluid doses are weight dependent in adults, but in resuscitation and low-resource settings it can be impractical or impossible to weigh a patient. It is especially important to obtain accurate weight estimation for dose calculations for emergency drugs with narrow therapeutic ranges. Several weight estimation methods have been proposed for use in adults, but none is widely established. The aim of this study was to compare the accuracy of adult weight estimation methods.

METHODS

Demographic and body measurement data were obtained from the US National Health and Nutrition Examination Survey (NHANES), and 7 previously published weight estimation methods were used to estimate the weight for each individual. The primary outcomes were the proportions of estimates within 10% and 20% of actual weight (P10, P20). An acceptable accuracy was predetermined to be P10 = 70% and P20 = 95%.

RESULTS

The data set included 5158 adults (51.2% women) with sufficient data to calculate all weight estimation methods. The Lorenz method performed best (P10 = 86.8%, P20 = 99.4%) and met the standard of acceptability across sex and body mass index subgroups. The Mercy and PAWPER XL-MAC methods performed acceptably in non-obese adults.

CONCLUSION

The ideal weight estimation method should be accurate, rapid, simple, and feasible. This study has demonstrated the accuracy of 7 methods. The Lorenz method performed best but is complex and likely to be difficult to apply in resuscitation settings. Other simpler and quicker methods are at least as accurate as the best methods widely used in children, and there is potential for further calibrating these for use in adults before validation in real-world studies.

Effect of erroneous body-weight estimation on outcome of thrombolyzed stroke patients

Intravenously administered tissue plasminogen activator (IV-tPA), dose determined by patients' body-weight, remains the only approved drug treatment for acute ischemic stroke (AIS). Since a shorter onset-to-treatment time results in better functional outcome, treatment is often initiated according to the estimated or last-known body-weight of the patient. This approach may result in underdosing or overdosing of tPA. In this multicenter retrospective study, we evaluated the extent of error in tPA dosing in our AIS cohort and its impact on functional outcome and symptomatic intracranial hemorrhage (SICH). Consecutive AIS patients, receiving IV-tPA, dose determined by the estimated body-weight, at three tertiary centers between January and December 2017 were included. Collected data included information about demographics, cardiovascular risk factors, stroke subtype and National Institute of Health Stroke Scale (NIHSS) score. Estimated and measured body-weights were recorded. Modified Rankin scale (mRS) of 2 or more defined unfavorable outcome. The study included 150 patients. Median age was 64 -years (IQR 55-75) with male preponderance (67%) and median NIHSS score of 9 points (IQR 6-17). Mean measured weight of our study population was 58 (SD 13) kg. Median difference between actual and estimated body-weight was 3 kg (IQR 1.5-6). Difference was more than 10% in 35 (23.3%) patients. Good functional outcome (mRS 0-1) was achieved by 74 (49.3%) patients and 10 (6.8%) developed SICH. NIHSS (OR 1.288; 95% CI 1.157-1.435, p < 0.001) and large artery atherosclerosis (OR 5.878; 95% CI 1.929-17.910, p = 0.002) were independent predictors of unfavorable functional outcome. Our finding of the statistically insignificant 2.5-fold increase in poor outcomes among patients where the estimated and actual weight differed by more than 10% should be interpreted with caution due to the limited sample size. Significant difference occurs between estimated and actual body-weight in a considerable proportion of thrombolysed AIS patients. However, this discrepancy does not affect functional outcome or the risk of SICH.

Assessment of body weight from percutaneous widths of the bones and joints-Implications in forensic and clinical examinations

BACKGROUND

Estimation of age, stature, sex, and ancestry contributes to the establishment of the biological profile of the deceased in forensic examinations. Assessment of the body weight aids in the approximation of the overall body size of the individual which may help in the forensic identification process. In clinical examinations, body weight assessment assumes importance in cases where body weight measurement is a challenging task due to illness and body deformity.

OBJECTIVE

The present research was conducted to estimate the body weight from the percutaneous width of the bones and joints with the help of prediction equations.

METHODS

The study was carried out on 344 adults (172 Females and 172 Males) aged between 18 and 25 years from the Himachal Pradesh State of North India. Eleven anthropometric measurements including height vertex, mid-arm circumference, humerus bicondylar width, transverse chest breadth, sagittal chest breadth, bi-iliac breadth, handbreadth, femur bicondylar breadth, ankle breadth, foot breadth, and body weight were taken on each individual. The sex differences were evaluated by using independent student t-test and Mann-Whitney U test and the correlation between the body weight and the anthropometric variables was investigated by using both Karl Pearson's correlation coefficient and Spearman's rank correlation coefficient depending upon the normality of the data. Regression models for the estimation of body weight were calculated. Further, a validation study was carried out to check the accuracy and utility of the derived regression models by calculating the mean absolute percent prediction error (MAPPE).

RESULTS

Significant sex differences were observed among all the anthropometric variables. The transverse chest breadth and mid-arm circumference were strongly correlated with the body weight, whereas, a good correlation was also observed in other measurements except for the ankle breadth. The SEE (Standard error of estimate) of the derived linear regression models was compared, and it was found that multiple linear regression models show better accuracy than simple linear regression models. The MAPPE was found to be less in the case of multiple linear regression models than the linear ones.

CONCLUSION

The present investigation concludes that regression models can be used in the estimation of body weight from the percutaneous measurements and joint widths with reasonable accuracy in an Indian population.

Accuracy of Critical Care Transport Team Estimation of Patient Height and Weight in Scene Responses

Estimates of clinically relevant information, such as height, weight, blood loss, and burn area, have consistently been fraught with error in the health care setting. Seemingly little has been done in health care education to improve estimate outcomes. Standardized tools, most often in pediatric populations, have become commonplace to guide acute care management when misestimation of data points like height or weight would likely have its biggest impact on patient care and outcome. This article is a retrospective study of a critical care transport team's abilities to estimate patient height and weight in scene responses using the Glasgow Coma Scale score as an indicator for the likelihood of patient input. Ultimately, height was removed as a variable because of the paucity and unreliability of the collected data. The expected outcome with respect to weight estimates was observed; with decreased patient Glasgow Coma Scale scores, the discrepancy in provider estimate increased from 8% to 12%. Although statistically significant, it does not represent the level of aberrancy noted in other studies, which has been reported to be as high as 40%.

Single-slice CT measurements allow for accurate assessment of sarcopenia and body composition

OBJECTIVES

To evaluate the correlation between simple planimetric measurements in axial computed tomography (CT) slices and measurements of patient body composition and anthropometric data performed with bioelectrical impedance analysis (BIA) and metric clinical assessments.

METHODS

In this prospective cross-sectional study, we analyzed data of a cohort of 62 consecutive, untreated adult patients with advanced malignant melanoma who underwent concurrent BIA assessments at their radiologic baseline staging by CT between July 2016 and October 2017. To assess muscle and adipose tissue mass, we analyzed the areas of the paraspinal muscles as well as the cross-sectional total patient area in a single CT slice at the height of the third lumbar vertebra. These measurements were subsequently correlated with anthropometric (body weight) and body composition parameters derived from BIA (muscle mass, fat mass, fat-free mass, and visceral fat mass). Linear regression models were built to allow for estimation of each parameter based on CT measurements.

RESULTS

Linear regression models allowed for accurate prediction of patient body weight (adjusted R² = 0.886), absolute muscle mass (adjusted R² = 0.866), fat-free mass (adjusted R² = 0.855), and total as well as visceral fat mass (adjusted R² = 0.887 and 0.839, respectively).

CONCLUSIONS

Our data suggest that patient body composition can accurately and quantitatively be determined by using simple measurements in a single axial CT slice. This could be useful in various medical and scientific settings, where the knowledge of the patient's anthropometric parameters is not immediately or easily available.

KEY POINTS

• Easy to perform measurements on a single CT slice highly correlate with clinically valuable parameters of body composition. • Body composition data were acquired using bioelectrical impedance analysis to correlate CT measurements with a non-imaging-based method, which is frequently lacking in previous studies. • The obtained equations facilitate a quick, opportunistic assessment of relevant parameters of body composition.

Mid-arm circumference method is invalid to estimate the body weight of elderly Emergency Department patients in the Netherlands

In the Emergency Department (ED) actual body weight (ABW) is essential for accurate drug dosing. Frequently, the ABW is unknown and direct measurement troublesome. A method using the mid-arm circumference (MAC) to estimate ABW has been developed and validated in the United States of America (USA). This study aimed to validate the MAC-formula for estimating ABW in the Dutch population and compare its performance within the American population.Data were obtained from the Dutch National Institute for Public Health and the Environment (RIVM) and extracted from the American National Health and Nutrition Examination Survey (NHANES) datasets. We included all subjects' ≥70 years whose MAC and weight were recorded and obtained additional anthropometric data. We used the equation: kg = 4 × MAC-50 to estimate the ABW of all subjects and compared results.We retrieved 723 and 972 subjects from the Dutch and American dataset, respectively. The MAC is better correlated with ABW in the American dataset when compared with the Dutch dataset (Pearson r = 0.84 and 0.68, respectively). Bland-Altman bias was -7.49 kg (Limits-of-Agreement [LOA] -27.5 to 12.27 kg) and -0.50 kg (LOA -20.99 to 19.99 kg) in the Dutch and American datasets, respectively.The MAC based formula to estimate ABW is a promising tool for the elderly American population. However it is not accurate within the Dutch elderly ED population. Consequently, it is not applicable to Dutch EDs. This study highlights that the results of anthropometric studies performed within the USA are not per se generalizable to the European population.

Body Weight Estimation for Dose-Finding and Health Monitoring of Lying, Standing and Walking Patients Based on RGB-D Data

This paper describes the estimation of the body weight of a person in front of an RGB-D camera. A survey of different methods for body weight estimation based on depth sensors is given. First, an estimation of people standing in front of a camera is presented. Second, an approach based on a stream of depth images is used to obtain the body weight of a person walking towards a sensor. The algorithm first extracts features from a point cloud and forwards them to an artificial neural network (ANN) to obtain an estimation of body weight. Besides the algorithm for the estimation, this paper further presents an open-access dataset based on measurements from a trauma room in a hospital as well as data from visitors of a public event. In total, the dataset contains 439 measurements. The article illustrates the efficiency of the approach with experiments with persons lying down in a hospital, standing persons, and walking persons. Applicable scenarios for the presented algorithm are body weight-related dosing of emergency patients.

A new method for estimating patient body weight using CT dose modulation data

Background

Body weight (BW) is a relevant metric in emergency care. However, visual/physical methods to estimate BW are unreliable. We have developed a method for estimating BW based on effective mAs (mAs_eff) from computed tomography (CT) dose modulation.

Methods

The mAs_eff of CT examinations was correlated with the BW of 329 decedents. Linear regression analysis was used to calculate an equation for BW estimation based on the results of decedents with a postmortem interval (PMI) < 4 days (n = 240). The equation was applied to a validation group of 125 decedents. Pearson correlation and t-test statistics were used.

Results

We found an overall strong correlation between mAs_eff and BW (r = 0.931); r values ranged from 0.854 for decedents with PMI ≥ 4 days to 0.966 for those with PMI < 4 days; among the latter group, r was 0.974 for females and 0.960 for males and 0.969 in the presence and 0.966 in the absence of metallic implants (all correlations with p values < 0.001). The estimated BW was equal to 3.732 + (0.422 × mAs_eff) – (3.108 × sex index), where the sex index is 0 for males and 1 for females. The validation group showed a strong correlation (r = 0.969) between measured BW and the predicted BW, without significant differences overall (p = 0.119) as well as in female (p = 0.394) and in male decedents (p = 0.196). No outliers were observed.

Conclusions

CT dose modulation is a rapid and reliable method for BW estimation with potential use in clinical practice, in particular in emergency settings.

Automatic RBG-depth-pressure anthropometric analysis and individualised sleep solution prescription

INTRODUCTION

Sleep surfaces must adapt to individual somatotypic features to maintain a comfortable, convenient and healthy sleep, preventing diseases and injuries. Individually determining the most adequate rest surface can often be a complex and subjective question.

OBJECTIVES

To design and validate an automatic multimodal somatotype determination model to automatically recommend an individually designed mattress-topper-pillow combination.

METHODS

Design and validation of an automated prescription model for an individualised sleep system is performed through a single-image 2 D-3 D analysis and body pressure distribution, to objectively determine optimal individual sleep surfaces combining five different mattress densities, three different toppers and three cervical pillows.

RESULTS

A final study (n = 151) and re-analysis (n = 117) defined and validated the model, showing high correlations between calculated and real data (>85% in height and body circumferences, 89.9% in weight, 80.4% in body mass index and more than 70% in morphotype categorisation).

CONCLUSIONS

Somatotype determination model can accurately prescribe an individualised sleep solution. This can be useful for healthy people and for health centres that need to adapt sleep surfaces to people with special needs. Next steps will increase model's accuracy and analise, if this prescribed individualised sleep solution can improve sleep quantity and quality; additionally, future studies will adapt the model to mattresses with technological improvements, tailor-made production and will define interfaces for people with special needs.

Dosage Calculation for Intravenous Thrombolysis of Ischemic Stroke: To Weigh or to Estimate

BACKGROUND

Estimation is a widely used method of assessing the weight of patients with acute stroke. Because the dosage of tissue plasminogen activator (tPA) is weight-dependent, errors in estimation lead to incorrect dosing.

METHODS

We installed a ground-level scale in the computed tomography (CT) suite of our hospital and also integrated a scale into the CT table of our Mobile Stroke Unit in order to prospectively assess the differences between reported, estimated, and measured weights of acute stroke patients. An independent rater asked patients to report their weight. The patients' weights were also estimated by the treating physician and measured with a scale. Differences between reported, estimated, and measured weights were analyzed statistically.

RESULTS

For 100 consecutive patients, weighing was possible without treatment delays. Weights estimated by the physician diverged from measured weights by 10% or more for 27 patients and by 20% or more for 6 patients. Weights reported by the patient diverged from measured weights by 10% or more for 12 patients. Weights reported by the patients differed significantly less from measured weights (mean, 4.1 ± 3.1 kg) than did weights estimated by the physician (5.7 ± 4.4 kg; p = 0.003).

CONCLUSION

This first prospective study of weight assessment in acute stroke shows that the use of an easily accessible scale makes it feasible to weigh patients with acute stroke without the treatment delay associated with additional patient transfers. Physicians' estimates of patients' weights demonstrated substantial aberrations from measured weights. Avoiding these deviations would improve the accuracy of tPA dosage.

The effect that energy storage and return feet have on the propulsion of the body: a pilot study

A variety of energy storage and return prosthetic feet are currently available for use within lower limb prostheses. Designs claim to provide a beneficial energy return during push-off, but the extent to which this occurs remains disputed. Techniques currently used to measure energy storage, dissipation and return within the structure of the prosthetic foot are debatable, with limited evidence to support substantial elastic energy storage and return from existing designs. The aim of this study was to evaluate the performance of energy storage and return foot designs through considering the ankle power during push-off and the effect on body centre of mass propulsion. To achieve this aim, the gait patterns of six trans-tibial prosthetic users wearing different designs of energy storage and return feet were analysed while ascending a ramp. Three examples of energy storage and return feet (suitable for moderate activity) were selected and randomly evaluated: the Blatchford's Epirus, Össur Assure and College Park Tribute feet. The power at the anatomical and mechanical ankle joints was integrated to evaluate the work done over the gait cycle. The direction of the inertial force, and therefore propulsion of the body centre of mass, was used to indicate the effect of the energy return by the energy storage and return feet. Results indicate that although energy storage and return feet may provide energy return, the work done around the prosthetic ankle indicates net power absorption. Therefore, the prosthetic limb is unable to contribute to the body centre of mass propulsion to the same extent as the biological limb.

Thrombolytic dosing in acute ischaemic stroke

Thrombolysis treatment for acute ischaemic stroke is effective if it is administered within 4.5 hours of stroke onset. Alteplase is a licensed thrombolytic treatment for ischaemic stroke. The dose of alteplase is dependent on a patient's weight. The stroke team involved in the administration of the treatment usually estimates a patient's weight prior to the treatment in order to ensure the correct dosage. This paper highlights the reliability of body weight estimates in determining the accuracy of thrombolysis dosing and the implication of dosing errors to post-thrombolysed patients.

Estimation of body weight in hospitalized patients

AIM

To examine the bias and precision of different methods of estimating body mass and height in hospitalized adult patients.

METHODS

Patients were enrolled at the Alfred and Caulfield hospitals, Melbourne, Australia following verbal consent. Estimates were made using the Lorenz formula (that utilizes height, waist and hip circumference), the Crandell formula (that utilizes height and arm circumference) and visual estimation of weight based on the average results obtained by two pharmacy interns. Statistical error was calculated as the ratio of estimated to actual weight; bias was assessed as the mean error and precision as the proportion of estimates within 10 and 20% of measured weight and standard deviation of the error.

RESULTS

In a 5-week period July to August 2010, 198 patients were enrolled. The median age was 64 years (range 19-91) and 52% were female. Thirty-four (17%) patients were obese (BMI >30 kg/m(2)) and 8 (4%) were underweight (BMI <18 kg/m(2)). With the Lorenz formula an estimate within 10% was obtained for 56% of patients; with the Crandell formula prediction was poor. Documentation of body weight in notes and patient self-reporting were both accurate. Seventy-two patients (43%) were prescribed one or more drugs for which dosing potentially should be adjusted for body weight.

CONCLUSION

In adult hospitalized patients, the estimation of body weight by anthropomorphic measures is not accurate. This supports the need for equipment to be made widely available to accurately weigh patients directly in hospital, including in unconscious and immobile patients.

Is the Maximum Dose of 90 mg Alteplase Sufficient for Patients With Ischemic Stroke Weighing >100 kg?

Background and Purpose—

Intravenous alteplase for acute ischemic stroke has a maximum dose limit of 90 mg. Consequently, patients >100 kg body weight receive a lower per-kilogram dose compared with those ≤100 kg. We investigated if the lower per-kilogram dose is associated with poor early neurological improvement and worse outcome after thrombolysis.

Methods—

Of 27 910 patients registered in Safe Implementation of Treatment in Stroke–International Stroke Thrombolysis Register (SITS-ISTR; 2002 to 2009), 1190 (4.3%) weighed >100 kg. Major neurological improvement was used to estimate recanalization (National Institutes of Health Stroke Scale improvement ≥8 points or score of 0 at 24 hours). Outcome measures included symptomatic intracerebral hemorrhage (National Institutes of Health Stroke Scale deterioration ≥4 points within 24 hours and Type 2 parenchymal hemorrhage), functional independence (modified Rankin Scale 0 to 2), and mortality at 3 months.

Results—

Patients >100 kg received a lower per-kilogram alteplase dose (0.82 versus 0.90, P <0.001), were younger (62 versus 70 years, P <0.001), had a lower baseline National Institutes of Health Stroke Scale (10 versus 12, P <0.001), but more frequently had cardiovascular risk factors. Major neurological improvement at 24 hours occurred in 27.7% in both groups. Symptomatic intracerebral hemorrhage occurred in 2.6% versus 1.7% ( P =0.03) in >100 kg versus ≤100 kg. Functional independence was 59.7% versus 53.6% ( P <0.001) and mortality was 14.4% versus 15.1% ( P =0.54). After adjustment for baseline characteristics, there was no significant difference for major neurological improvement or functional independence between >100 kg and ≤100 kg, but >100-kg patients had a higher odds ratio for symptomatic intracerebral hemorrhage (OR, 1.6; 95% CI, 1.06 to 2.41; P =0.02) and mortality (OR, 1.37; 95% CI, 1.08 to 1.74; P =0.01).

Conclusions—

Our results support the current upper dose limit. There was a higher incidence of symptomatic intracerebral hemorrhage in patients >100 kg despite the lower per-kilogram recombinant tissue plasminogen activator dose. Major neurological improvement and functional independence were similar.