Implementing Wearable Sensors for Clinical Application at a Surgical Ward:Points to Consider before Starting

Incorporating technology into healthcare processes is necessary to ensure the availability of high-quality care in the future. Wearable sensors are an example of such technology that could decrease workload, enable early detection of patient deterioration, and support clinical decision making by healthcare professionals. These sensors unlock continuous monitoring of vital signs, such as heart rate, respiration rate, blood oxygen saturation, temperature, and physical activity. However, broad and successful application of wearable sensors on the surgical ward is currently lacking. This may be related to the complexity, especially when it comes to replacing manual measurements by healthcare professionals. This report provides practical guidance to support peers before starting with the clinical application of wearable sensors in the surgical ward. For this purpose, the Non-Adoption, Abandonment, Scale-up, Spread, and Sustainability (NASSS) framework of technology adoption and innovations in healthcare organizations is used, combining existing literature and our own experience in this field over the past years. Specifically, the relevant topics are discussed per domain, and key lessons are subsequently summarized.</p

Validation of a Length-Adjusted Abdominal Arterial Calcium Score Method for Contrast-Enhanced CT Scans

BACKGROUND: The Agatston score on noncontrast computed tomography (CT) scans is the gold standard for calcium load determination. However, contrast-enhanced CT is commonly used for patients with atherosclerotic cardiovascular diseases (ASCVDs), such as peripheral arterial occlusive disease (PAOD) and abdominal aortic aneurysm (AAA). Currently, there is no validated method to determine calcium load in the aorta and peripheral arteries with a contrast-enhanced CT. This study validated a length-adjusted calcium score (LACS) method for contrast-enhanced CT scans.METHOD: The LACS (calcium volume in mm 3/arterial length in cm) in the abdominal aorta was calculated using four-phase liver CT scans of 30 patients treated between 2017 and 2021 at the University Medical Center Groningen (UMCG) with no aortic disease. Noncontrast CT scans were segmented with a 130 Hounsfield units (HU) threshold, and a patient-specific threshold was used for contrast-enhanced CTs. The LACS was calculated and compared from both segmentations. Secondly, the interobserver variability and the influence of slice thickness (0.75 mm vs. 2.0 mm) was determined. RESULTS: There was a high correlation between the LACS from contrast-enhanced CT scans and the LACS of noncontrast CTs ( R 2 = 0.98). A correction factor of 1.9 was established to convert the LACS derived from contrast-enhanced CT to noncontrast CT scans. LACS interobserver agreement on contrast-enhanced CT was excellent (1.0, 95% confidence interval = 1.0-1.0). The 0.75 mm CT threshold was 541 (459-625) HU compared with 500 (419-568) HU on 2 mm CTs ( p = 0.15). LACS calculated with both thresholds was not significantly different ( p = 0.63). CONCLUSION: The LACS seems to be a robust method for scoring calcium load on contrast-enhanced CT scans in arterial segments with various lengths.</p

On the evaluation of some distributions that arise in simultaneous tests for the equality of the latent roots of the covariance matrix

In this paper, the authors consider the evaluation of the distribution functions of the ratios of the intermediate roots to the trace of the real Wishart matrix as well as the ratios of the individual roots to the trace of the complex Wishart matrix. In addition, the authors consider the evaluation of the distribution functions of the ratios of the extreme roots of the Wishart matrix in the real and complex cases. Some applications and tables of the above distributions are also given.Exact distributions ratios of the roots Wishart matrix multiple time series tests for additivity simultaneous tests mixture of populations

On the distributions of the ratios of the extreme roots to the trace of the Wishart matrix

In this paper, the authors cosider the derivation of the exact distributions of the ratios of the extreme roots to the trace of the Wishart matrix. Also, exact percentage points of these distributions are given and their applications are discussed.Exact distributions ratios of the extreme roots to the trace Wishart matrix

Changes in Apposition of Endograft Limbs in the Iliac Arteries After Endovascular Aneurysm Repair:Determination With New Computed Tomography-Applied Software

Purpose: To validate new computed tomography (CT)-applied software used to determine endograft limb position and apposition after endovascular aneurysm repair (EVAR). Materials and Methods: Twelve EVAR patients (mean age 81 +/- 6 years; 10 men) with distal stent-graft extensions for 15 (3 bilateral) type Ib endoleaks during follow-up were selected based on the availability of the following CT studies: pre-EVAR, 1 month, and the penultimate scan prior to the scan disclosing the type Ib endoleak. Twelve patients (mean age 82 +/- 7 years; 11 men) without endoleak and a similar interval between the primary EVAR procedure and the penultimate CT scan of the endoleak group were selected as controls using measurements from both endograft limbs (n=21, 3 excluded). Prototype Vascular Imaging Analysis software was adapted to calculate 6 parameters for the distal apposition zone: fabric distance, shortest apposition length, endograft diameter, iliac seal surface (ISS), iliac endograft apposition surface (IEAS), and percentage of iliac surface coverage (IEAS/ISS x 100). Measurements were performed on the preoperative, first postoperative, and penultimate/matched follow-up CT scans. Interobserver variability was assessed with the intraclass correlation coefficient (ICC). Continuous data are presented as the median [interquartile range (IQR) Q1, Q3]. Results: CTA follow-up was not significantly different between the endoleak and control groups [30 months (IQR 18, 58) vs 36 months (IQR 21, 59), p=0.843]. Interobserver agreement was good to excellent for all parameters (ICC 0.879-0.985). Preoperative anatomy and endograft dimensions on the first follow-up CTA scan did not differ significantly between the groups. When the penultimate CTA scan was compared with the first postoperative CT scan, endograft dimensions had significantly changed in the endoleak group; importantly, apposition was significantly decreased, and fabric distance was significantly increased, indicating limb retraction. Differences in changes in endograft dimensions were significant between the groups. Conclusion: New CT-applied software was introduced to visualize apposition and position changes of endograft limbs during follow-up. The software demonstrated good-to-excellent interobserver agreement and enabled accurate analysis of post-EVAR endograft dimensions. Significant changes in apposition and position were observed with the software on the penultimate CT scan prior to diagnosis of type Ib endoleak

Clinical Applications of Conebeam CTP Imaging in Cerebral Disease:A Systematic Review

BACKGROUND: Perfusion imaging with multidetector CT is integral to the evaluation of patients presenting with ischemic stroke due to large-vessel occlusion. Using conebeam CT perfusion in a direct-To-Angio approach could reduce workflow times and improve functional outcome.PURPOSE: Our aim was to provide an overview of conebeam CT techniques for quantifying cerebral perfusion, their clinical applications, and validation.DATA SOURCES: A systematic search was performed for articles published between January 2000 and October 2022 in which a conebeam CT imaging technique for quantifying cerebral perfusion in human subjects was compared against a reference technique.STUDY SELECTION: Eleven articles were retrieved describing 2 techniques: dual-phase (n = 6) and multiphase (n = 5) conebeam CTP. DATA ANALYSIS: Descriptions of the conebeam CT techniques and the correlations between them and the reference techniques were retrieved.DATA SYNTHESIS: Appraisal of the quality and risk of bias of the included studies revealed little concern about bias and applicability. Good correlations were reported for dual-phase conebeam CTP; however, the comprehensiveness of its parameter is unclear. Multiphase conebeam CTP demonstrated the potential for clinical implementation due to its ability to produce conventional stroke protocols. However, it did not consistently correlate with the reference techniques.LIMITATIONS: The heterogeneity within the available literature made it impossible to apply meta-Analysis to the data.CONCLUSIONS: The reviewed techniques show promise for clinical use. Beyond evaluating their diagnostic accuracy, future studies should address the practical challenges associated with implementing these techniques and the potential benefits for different ischemic diseases.</p

Quantification of muscle mass in the legs of patients with peripheral arterial occlusive disease:associations between volumetric and cross-sectional single-slice measurements for identification of atrophy and focal sarcopenia

BACKGROUND: Sarcopenia, commonly determined by measuring skeletal muscle mass index (SMI) at the third lumbar level, has been identified as a predictor of clinical outcome in a variety of diseases. For patients with PAOD, we hypothesized that lower extremity skeletal muscle mass index (LESMI) might be a more precise predictor of outcome and the extent of chronic ischemia than the systemic muscle mass at the L3 level. We investigated the association between complete muscle volume and muscle area derived with single-slice 2- dimensional measurements in the legs to identify at which level cross-sectional single-slice measurements are most representative of the muscle volume and investigated whether LESMI is associated with systemic sarcopenia and PAOD severity. METHODS: Muscle volumes and areas were semiautomatically segmented from computed tomography (CT) scans of the affected and contralateral legs of 50 PAOD patients with Fontaine stage IIb and 50 PAOD patients with Fontaine stage IV. The muscle mass was determined for the complete volumes of the upper and lower legs and for cross-sectional slices at 40%, 50%, and 60% of the length of the femur and tibia. Patients were determined as sarcopenic based on sex-specific cutoff values at the L3 spinal segment. Two observers segmented 20 randomly selected patients to determine the interobserver reliability with the intraclass correlation coefficient. RESULTS: The correlation between the LESMI of the complete muscle volume and the three cross-sectional slices in all 200 upper and 200 lower legs was moderately strong to strong. Interobserver reliability of cross- sectional slice segmentation was excellent. The LESMI, both measured volumetrically and cross-sectionally, were significantly lower in patients with sarcopenia compared to patients without sarcopenia. The LESMI was lower in patients with Fontaine stage IV compared with patients with Fontaine stage IIb for both volumetric and cross-sectional measurements. CONCLUSIONS: Segmentation of skeletal muscle mass from cross-sectional single-slice CT in the upper and lower leg can accurately and precisely substitute complete volume segmentations. These findings warrant the use of measurements based on cross-sectional single-slice CT for assessing the LESMI. Patients with systemic sarcopenia are also at increased risk for muscle mass loss in the lower extremities. In the current study, LESMI was lower in patients with Fontaine class IV PAOD compared to patients with Fontaine classIIb PAOD. Future studies should assess the predictive value of the LESMI on clinical outcomes in PAOD patients

Determination of the gained proximal sealing zone length after debranching of the left subclavian artery in thoracic endovascular aortic repair.

BACKGROUND: For descending thoracic aortic aneurysms (TAA) in proximity of the aortic arch, debranching of the left subclavian artery (LSA) may be necessary to extend proximal sealing in zone 2. The aim of this study was to determine the added proximal apposition length gained from LSA debranching during thoracic endovascular aortic repair (TEVAR). METHODS: This multicenter retrospective study (2010-2020) included patients who underwent elective TEVAR in zone 2 for a degenerative TAA where the LSA was surgically debranched. The endograft position on the first postoperative computed tomography angiography (CTA) scan was assessed using post-processing software. The analysis included the shortest apposition length (SAL), the tilt of the proximal edge of the endograft, and the distance between the endograft and the left common carotid artery. Clinical endpoints (neurological complications and endoleaks) at 30 days were also reported. RESULTS: Twenty-two patients were included. The median interval between TEVAR and the first postoperative CTA was 3 days (2-10 days). Median SAL was 9.2 mm (1.3-26.4 mm), of which 8.6 mm (1.3-16.2 mm) was gained proximal of the LSA, including the LSA orifice. In 12 patients (55.5%) the SAL was <10 mm. The median tilt was 18.3° (13.9°-22.2°). Seven endoleaks were reported on the first CTA: 1 type Ia, 2 type Ib, 3 type II, and 1 type III. CONCLUSIONS: Debranching the LSA adds valuable sealing length in zone 2, but the SAL was still relatively short in many patients, putting these patients at risk for a future type Ia endoleak. Accurate assessment of the circumferential apposition on postoperative CTA follow-up in these high-risk patients with short, complex landing zones seems mandatory. Evaluation of apposition in a larger population with longer follow-up is advised