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51.
Christian B. Ong Chad A. Krueger Andrew M. Star 《The Journal of arthroplasty》2021,36(8):2658-2664.e2
BackgroundMedically complex patients require more resources and experience higher costs within total joint arthroplasty (TJA) bundled payment models. While risk adjustment would be beneficial for such patients, no tool currently exists which can reliably identify these patients preoperatively. The purpose of this study is to determine if the Hospital Frailty Risk Score (HFRS) is a valid predictor of high-TJA treatment costs.MethodsRetrospective analysis was performed on patients who underwent primary TJA between 2015 and 2020 from a single large orthopedic practice. ICD-10 codes from an institutional database were used to calculate HFRS. Cost data including inpatient, postacute, and episode of care (EOC) costs were collected. Charlson comorbidity index, demographics, readmissions, and complications were analyzed.Results4936 patients had a calculable HFRS and those with intermediate and high scores experienced more frequent readmissions/complications after TJA, as well as higher EOC costs. However, HFRS did not reliably predict EOC costs, yielding a sensitivity of 49% and specificity of 66%. Multivariate analysis revealed that both patient age and sex are superior individual cost predictors when compared with HFRS. Secondary analyses indicated that HFRS more effectively predicts TJA complications and readmissions but is still nonideal for clinical applications.ConclusionHFRS has poor sensitivity as a predictor of high-EOC costs for TJA patients but has adequate specificity for predicting postoperative readmissions and complications. Further research is needed to develop a scale that can appropriately predict orthopedic cost outcomes. 相似文献
52.
Seongmin Kim Kyung Jin Min Sanghoon Lee Jin Hwa Hong Jae Yun Song Jae Kwan Lee Nak Woo Lee 《Asian journal of surgery / Asian Surgical Association》2021,44(1):174-180
Background/ObjectiveRecent prospective studies have shown poorer oncologic outcomes following minimally invasive surgery, which has led many surgeons to deeply inspect their practices. We reviewed our experience and evaluated the results of radical hysterectomy in patients with early stage cervical cancer.MethodsThis retrospective study included patients with early stage cervical cancer (Ia1 - IIa1) who were treated with radical hysterectomy from May 2006 to Dec 2016. Patients were divided into three groups according to the surgical approach: radical abdominal hysterectomy (RAH), laparoscopic radical hysterectomy (LRH), and robot-assisted radical hysterectomy (RRH).ResultsLearning curves of each type of surgery were obtained using the cumulative sum method. Survival rates were compared using Kaplan–Meier curves. To analyze the learning curve of a single surgeon, 89 patients were selected from the whole population. Learning curves of each group showed two distinct phases. The minimum number of cases required to achieve surgical improvement were 16 in RAH, 13 in LRH, and 21 in RRH. Progression-free survival (PFS) and overall survival did not vary between RAH and minimally invasive surgery (MIS) (p = .828 and p = .757, respectively). However, when stratified by the phases of the learning curves, patients included in the early phase of MIS showed a poorer PFS (p = .014).ConclusionsSurgical proficiency could significantly affect the oncologic outcome in MIS. A prospective study regarding sufficient surgical competence is necessary for elaborate analysis of the feasibility of minimally invasive radical hysterectomy. 相似文献
53.
54.
Dimitrios Moris Brian I. Shaw Cecilia Ong Ashton Connor Mariya L. Samoylova Samuel J. Kesseli Nader Abraham Jared Gloria Robin Schmitz Zachary W. Fitch Bryan M. Clary Andrew S. Barbas 《肝胆外科与营养》2021,10(3):315
BackgroundSelection of the optimal treatment modality for primary liver cancers remains complex, balancing patient condition, liver function, and extent of disease. In individuals with preserved liver function, liver resection remains the primary approach for treatment with curative intent but may be associated with significant mortality. The purpose of this study was to establish a simple scoring system based on Model for End-stage Liver Disease (MELD) and extent of resection to guide risk assessment for liver resections.MethodsThe 2005–2015 NSQIP database was queried for patients undergoing liver resection for primary liver malignancy. We first developed a model that incorporated the extent of resection (1 point for major hepatectomy) and a MELD-Na score category of low (MELD-Na =6, 1 point), medium (MELD-Na =7–10, 2 points) or high (MELD-Na >10, 3 points) with a score range of 1–4, called the Hepatic Resection Risk Score (HeRS). We tested the predictive value of this model on the dataset using logistic regression. We next developed an optimal multivariable model using backwards sequential selection of variables under logistic regression. We performed K-fold cross validation on both models. Receiver operating characteristics were plotted and the optimal sensitivity and specificity for each model were calculated to obtain positive and negative predictive values.ResultsA total of 4,510 patients were included. HeRS was associated with increased odds of 30-day mortality [HeRS =2: OR =3.23 (1.16–8.99), P=0.025; HeRS =3: OR =6.54 (2.39–17.90), P<0.001; HeRS =4: OR =13.69 (4.90–38.22), P<0.001]. The AUC for this model was 0.66. The AUC for the optimal multivariable model was higher at 0.76. Under K-fold cross validation, the positive predictive value (PPV) and negative predictive value (NPV) of these two models were similar at PPV =6.4% and NPV =97.7% for the HeRS only model and PPV =8.4% and NPV =98.1% for the optimal multivariable model.ConclusionsThe HeRS offers a simple heuristic for estimating 30-day mortality after resection of primary liver malignancy. More complicated models offer better performance but at the expense of being more difficult to integrate into clinical practice. 相似文献
55.
This study explored the determinants of consumer satisfaction with OTC drugs using the confirmation/disconfirmation model. A revised confirmation/disconfirmation model specifically for OTC drugs was proposed and tested using structural equation modeling with a specific product category: cold medications. The results of this study found that the confirmation/disconfirmation of a consumer's expectation and perceived performance of an OTC drug is important in predicting consumer satisfaction. Theoretical and managerial implications for pharmaceutical marketers are discussed. 相似文献
56.
Metabolite identification and urinary and biliary excretion of the new fluoroquinolone antibacterial agent DW116 [1-(5-fluoro-2-pyridyl)-6-fluoro-7-(4-methyl-1-piperazinyl)-1,4-dihydro-4-oxoquinoline-3-carboxylic
acid, hydrochloride] after oral administration have been studied in Sprague-Dawley rats. The excretion kinetics were monoexponential.
Most of the drug was eliminated via the hepatic and renal routes. Mean renal clearance of DW116 was 73.4 ml/hr/kg and mean
biliary clearance was 83.8 ml/hr/kg. The major metabolite excreted in the bile was identified as the glucuronide ester of
the parent drug using base-hydrolysis of the conjugate metabolite followed by co-HPLC with standard compound,19F-NMR and LC-MS methods. The glucuronide conjugate was also found in urine. The mean urinary recoveries of free and total
(free plus glucuronide ester) DW116 were 28.6±2.7% and 36.4±1.8% of the administered dose and the corresponding biliary recoveries
were 14.4±5.5% and 37.0±7.6%, respectively. 相似文献
57.
We assessed reproducible definition of two standardized co-ordinate systems for intersubject analysis of brain images. The baselines in the two co-ordinate systems were a modification of the canthomeatal (inCM) line and the anterior-posterior commissural )AC-PC) line. Axial spin-echo MR images of four subjects at 1.5T were used. Operator error was computed from the replicate analyses of two operators. The mCM line was determined by the lens of the eye and the internal auditory canal, and the AC-PC line was determined by the intersection of the AC and PC with the interhemispheric fissure. Reproducibility of the mCM markers (SD=0.59 mm) did not differ significantly from that of the AC-PC line (SD=0.68 mm). The measurement error of the angle of the baseline (), however, was more than 7 times as large for the AC-PC line as for the mCM line. An additional error affecting the rostrocaudal rotation of the co-ordinate systems, attributable to the distance between the anatomic markers, was 2.1 and 3.6° (3 mm and 5 mm slice thickness) for the mCM co-ordinate system and 8.2 and 11.0° (3 mm and 5 mm slice thickness) for the AC-PC system. The AC-PC line based co-ordinate system is therefore, less reproducible than the mCM line based system. this could be improved if a combination of axial and sagittal images were used for the definition of the AC-PC line. 相似文献
58.
Vedhara K Nott KH Richards SM Bradbeer C Davidson EA Ong EL Snow MH 《AIDS patient care》1995,9(6):276-280
Despite uncertainty over their reliability, CD4+ cell counts are used extensively in both clinical and research settings to document progression in HIV infection. We examined, therefore, whether the performance of a simple statistical test would facilitate greater accuracy in the use of this marker. CD4+ cell count data were collected from a cohort of deceased (N = 60) and living HIV-positive gay men (N = 100). Pearson's product moment correlation coefficients were calculated for each individual in order to examine the association between CD4+ counts and time since diagnosis. Correlations of 0.7 or greater were obtained in approximately 50 percent of cases in each cohort. For these individuals, CD4+ cell counts were deemed to be a reliable indicator of rate of progression. The results suggest that the proposed technique ensures greater precision in the use of CD4+ cell counts and that the technique cna be used in individuals with either complete (deceased patients) or partial (living patients) CD4+ data. 相似文献
59.
The relationship of scapulothoracic motion to glenohumeral motion, commonly referred to as the scapulohumeral rhythm, has been the subject of numerous investigations. The purpose of this study was to assess the effects of localized muscular fatigue on three-dimensional scapulothoracic motion and the resulting scapulohumeral rhythm during elevation of the humerus in the plane of the scapula. A six-degree-of-freedom digitizing system (Metrecom(TM)) was used to define scapular and trunk reference frames, and three-dimensional Eulerian angles were determined for scapular motion for 0-135 degrees of humeral elevation before and after fatigue of the upper and lower trapezius muscles. Local muscle fatigue was determined using spectral analysis of electromyographic signals for the upper and lower trapezius muscles. The results demonstrated an average of 22% decrease in the median frequencies of the muscles sampled following resistive exercise, suggesting a state of local muscle fatigue. Concomitant with the fatigue was a selective decrease in scapulothoracic motion about two of the three scapular axes. RELEVANCE: Occupational and recreational conditions often require repetitive overhead elevations of the arms, resulting in muscular fatigue and various pathologies. During repetitive arm elevations the scapulohumeral rhythm or synchronization between the humerus and the scapula is balanced to allow the most efficient elevation of the arm. A better understanding of this much-discussed scapulohumeral rhythm and the changes induced by muscular fatigue may provide insight into the pathomechanics associated with shoulder dysfunction. 相似文献
60.
54 sporadic colorectal cancers were analyzed for aberrations in the K-ras oncogene. DNA was extracted from frozen tissues obtained from surgical resection and analyzed for mutations in codons 12, 13 and 61 of the K-ras oncogene using single strand conformation polymorphism analysis (SSCP) and direct sequencing. Point mutations in the K-ras oncogene were found in 26/54 (48%) cases, all of which resulted in amino acid substitutions. No other types of mutations (e.g. insertions or deletions) were found. 4 of the mutations were at codon 12, 22 in codon 13 and only 1 was a codon 61 mutant. G-->A transitions were found to be predominant. A remarkable finding was the high preponderance of (13)Gly-(13)Ser mutations (54%). No correlation was observed between K-ras mutations and tumor location, Dukes' stage, differentiation levels, age or sex of the patient. 相似文献