Perceived exertion as a tool to self-regulate exercise in individuals with tetraplegia

The purpose of this investigation was to examine the use of subjective rating of perceived exertion (RPE) as a tool to self-regulate the intensity of wheelchair propulsive exercise in individuals with tetraplegia. Eight motor complete tetraplegic (C5/6 and below; ASIA Impairment Scale = A) participants completed a submaximal incremental exercise test followed by a graded exercise test to exhaustion to determine peak oxygen uptake ( $ \dot{V}O_{{ 2 {\text{peak}}}} $ ) on a wheelchair ergometer. On a separate day, a 20-min exercise bout was completed at an individualised imposed power output (PO) equating to 70 % of $ \dot{V}O_{{ 2 {\text{peak}}}} $ . On a third occasion, participants were instructed to maintain a workload equivalent to the average RPE for the 20-min imposed condition. $ \dot{V}O_{2} $ , heart rate (HR) and PO were measured at 1-min intervals and blood lactate concentration [BLa^?] was measured at 0, 10 and 20 min. No differences (P > 0.17) were found between mean $ \dot{V}O_{2} $ , %  $ \dot{V}O_{{ 2 {\text{peak}}}} $ , HR, % HR_peak, [BLa^?], velocity or PO between the imposed and RPE-regulated trials. No significant (P > 0.05) time-by-trial interaction was present for $ \dot{V}O_{2} $ data. A significant interaction (P < 0.001) for the PO data represented a trend for an increase in PO from 10 min to the end of exercise during the RPE-regulated condition. However, post hoc analysis revealed none of the differences in PO across time were significant (P > 0.05). In conclusion, these findings suggest that RPE can be an effective tool for self-regulating 20 min of wheelchair propulsion in a group of trained participants with tetraplegia who are experienced in wheelchair propulsion.     

Incidence of injury in elite junior Rugby Union: a prospective descriptive study

The high incidence of injury in Rugby Union is well documented, particularly at elite levels of competition. This article describes the incidence and nature of all injuries sustained by elite Western Australian junior Rugby Union players during the 26 weeks up to and including the 1997 National Championship campaign. Informed consent was gained for each participant (n = 44) prior to completion of an extensive baseline questionnaire. Exposure and injury data were collected at each training session and game. The injury incidence rate over the 26 week period was 13.26/1000 player hours. Injury data were analysed by phase of play, position, severity and if occurred at games or training. The incidence of injury was significantly associated with the position played (chi2 = 67.49, p value = 0.008) and the phase of play in which the injury occurred (chi2 = 8.07, p value = 0.042). Tackling was the most dangerous phase of play (52% of injuries) and the most common site of injury was the lower limb (37%). Most injuries occurred during games (56%) and the flanker was the position most at risk of injury (12%). Further research is needed to identify the aetiology of injury at all levels of competition and to use these findings to develop effective injury prevention strategies in this sport. Position-specific risk factors should also be investigated, as should the mechanism of injury associated with tackling which is the phase of play in which significantly more injuries occur in rugby.     

Dual-phase 3D MDCT angiography for evaluation of the liver before hepatic resection

OBJECTIVE: We sought to evaluate the accuracy of dual-phase MDCT angiography for assessing the liver before hepatic resection and to compare 2D and 3D images for quality and arterial branch visualization. MATERIALS AND METHODS: Sixty-three patients with colorectal metastases (n = 30), hepatocellular carcinomas (n = 13), giant hemangiomas (n = 5), and other lesions (n = 15) underwent dual-phase MDCT using either a LightSpeed QX/i 4-MDCT (n = 31) or LightSpeed QX/i Ultra 8-MDCT (n = 32) scanner. Contrast material (150 mL of Isovue 370 [iopamidol]) was injected at a rate of 5 mL/sec. The arterial phase images were rendered on a workstation to obtain 3D MDCT angiograms that were assessed by two reviewers who were blinded to the surgical findings. Arterial anatomy was categorized according to the Michels classification. The reviewers assessed the 2D and 3D images for quality, arterial branch visualization, and differences between the 4- and 8-MDCT images. In the 43 patients who underwent resection, imaging findings were correlated with intraoperative findings. RESULTS: The anatomy of hepatic arteries in the 63 patients was classified as follows: Michels type I, 51 patients (80.9%); type III, four patients (6.3%); type V, five patients (7.9%); and types VII, VIII, and IX, one patient (1.6%) each. In 40 (93%) of 43 patients, the surgical findings concurred with MDCT findings. Three discrepancies were due to failure to identify small accessory left hepatic arteries. Branch visualization and image quality of the 2D images were superior to those of the 3D images. No significant difference was found between the 4- and 8-MDCT images in branch visualization and image quality. CONCLUSION: Three-dimensional MDCT angiography is accurate for classification of hepatic arterial anatomy before hepatic resection. Although 2D data sets show small arteries to better advantage than 3D MDCT angiograms, the 3D MDCT angiograms provide a useful overview of hepatic anatomy.     

Thirty-day mortality of patients with hip fracture during COVID-19 pandemic and pre-pandemic periods: A systematic review and meta-analysis

BACKGROUNDTimely intervention in hip fracture is essential to decrease the risks of perioperative morbidity and mortality. However, limitations of the resources, risk of disease transmission and redirection of medical attention to a more severe infective health problem during coronavirus disease 2019 (COVID-19) pandemic period have affected the quality of care even in a surgical emergency.AIMTo compare the 30-d mortality rate and complications of hip fracture patients treated during COVID-19 pandemic and pre-pandemic times.METHODSThe search of electronic databases on 1^st August 2020 revealed 45 studies related to mortality of hip fracture during the COVID-19 pandemic and pre-pandemic times. After careful screening, eight studies were eligible for quantitative and qualitative analysis of data.RESULTSThe pooled data of eight studies (n = 1586) revealed no significant difference in 30-d mortality rate between the hip fracture patients treated during the pandemic and pre-pandemic periods [9.63% vs 6.33%; odds ratio (OR), 0.62; 95%CI, 0.33, 1.17; P = 0.14]. Even the 30-d mortality rate was not different between COVID-19 non-infected patients who were treated during the pandemic time, and all hip fracture patients treated during the pre-pandemic period (OR, 1.03; 95%CI, 0.61, 1.75; P = 0.91). A significant difference in mortality rate was observed between COVID-19 positive and COVID-19 negative patients (OR, 6.99; 95%CI, 3.45, 14.16; P < 0.00001). There was no difference in the duration of hospital stay (OR, -1.52, 95%CI, -3.85, 0.81; P = 0.20), overall complications (OR, 1.62; P = 0.15) and incidence of pulmonary complications (OR, 1.46; P = 0.38) in these two-time frames. Nevertheless, the preoperative morbidity was more severe, and there was less use of general anesthesia during the pandemic time.CONCLUSIONThere was no difference in 30-d mortality rate between hip fracture patients treated during the pandemic and pre-pandemic periods. However, the mortality risk was higher in COVID-19 positive patients compared to COVID-19 negative patients. There was no difference in time to surgery, complications and hospitalization time between these two time periods.     

Comparison of radiologists and technologists in the performance of air-contrast barium enemas

OBJECTIVE: The purpose of this study was to determine whether the rate of polyp detection and the quality of air-contrast barium enema (ACBE) procedures performed by technologists differ from those performed by radiologists. CONCLUSION: Our results showed that well-trained certified technologists can perform ACBE similar in overall quality and accuracy to ACBE performed by attending physicians and residents. Training technologists to perform ACBE may help to alleviate the radiology staffing shortage in the United States.     

Multi-slice echo-planar spectroscopic MR imaging provides both global and local metabolite measures in multiple sclerosis.

MR spectroscopy (MRS) provides information about neuronal loss or dysfunction by measuring decreases in N-acetyl aspartate (NAA), a metabolite widely believed to be a marker of neuronal viability. In multiple sclerosis (MS), whole-brain NAA (WBNAA) has been suggested as a marker of disease progression and treatment efficacy in treatment trials, and the ability to measure NAA loss in specific brain regions early in the evolution of this disease may have prognostic value. Most spectroscopic studies to date have been limited to single voxels or nonlocalized measurements of WBNAA only, and longitudinal studies have often been hampered by standardization and reproducibility problems. Multi-slice echo-planar spectroscopic imaging (EPSI) is presented as a promising alternative to single-voxel or nonlocalized spectroscopy for obtaining global metabolite estimates in MS. In the same session, measurements of metabolites in specific brain areas chosen after image acquisition (e.g., normal-appearing white matter (NAWM), gray matter (GM), and lesions) can be obtained. The identification and exclusion of regions that are inadequate for spectroscopic evaluation in global assessments can significantly improve quality and reproducibility, as demonstrated by a low within-subject variance in healthy controls. The reproducibility of the technique makes it a promising tool for future longitudinal spectroscopic studies of MS.     

Metabolic and physiological differences between zero-flow and low-flow myocardial ischemia: effects of L-acetylcarnitine

Summary The metabolic and physiologic differences between low-flow and zero-flow ischemia of varying duration were compared in the isolated perfused rat heart. Hearts subjected to 60 and 90 minutes of zero-flow ischemia recovered less cardiac work than hearts subjected to low-flow ischemia. Low-flow ischemia caused a build-up of both myocardial long-chain acyl coenzyme A and acyl carnitine esters, while zero-flow ischemia produced no change in long-chain acyl carnitine and only a transient increase in long-chain acyl coenzyme A. High energy phosphate depletion was greater in zero-flow ischemia. Perfusion with excess free fatty acids decreased the recovery of cardiac work after low-flow ischemia but had no effect after repeated episodes of zero-flow ischemia. L-Acetylcarnitine improved the recovery of cardiac work after low-flow ischemia in hearts perfused with 0.4 and 1.2 mM palmitate. With zero-flow ischemia, L-acetylcarnitine had no effect on the recovery of cardiac work in hearts perfused with 0.4 mM palmitate and a slight but statistically significant effect with 1.2 mM palmitate. Possible protective mechanisms of L-acetylcarnitine against ischemic damage are discussed.     

Accumulation of methotrexate and methotrexate polyglutamates in lymphoblasts at diagnosis of childhood acute lymphoblastic leukemia: a pilot prognostic factor analysis

Lymphoblasts in bone marrow samples, obtained from 43 children with acute lymphoblastic leukemia at diagnosis, were incubated with 1.0 mumols/L [3H] methotrexate for 24 hours in vitro. Nonexchangeable methotrexate and methotrexate polyglutamates were separated and quantitated. Event-free survival at 5 years was 38% +/- 9% for all 43 patients (27 failures), and 44% +/- 10% for the 35 with non-T, non-B- cell acute lymphoblastic leukemia (20 failures). Of these 35 children, those whose lymphoblasts accumulated more than 100 pmol methotrexate and 500 pmol methotrexate polyglutamates per billion cells experienced better 5-year event-free survival than those whose lymphoblasts did not (65% +/- 12% v 22% +/- 9%, P = .010). This difference characterized "good-risk" patients who were female (P = .014), less than age 7 at diagnosis (P = .005), or had low initial white blood cell counts (less than 20 X 10(9)/L, P = .018). Findings were similar for the 43 children with acute lymphoblastic leukemia and for the "good-risk" children in this total group. Thus, the ability of lymphoblasts to accumulate methotrexate and form methotrexate polyglutamates may be important to the curative properties of current therapy of acute lymphoblastic leukemia in children, particularly for "good-risk" patients. In such patients, inherent rather than acquired drug resistance may be the initial event leading to treatment failure.     

Modified two-stage basilic vein transposition for hemodialysis access

Background

Various techniques for basilic vein transposition have been described, including endovascular, 1-stage, and 2-stage transposition. However, none of these 2-stage techniques include a new arteriovenous anastomosis during the second stage. This study adds to the current literature as well as introducing a new and innovative technique for hemodialysis access.

Methods

Forty-nine basilic vein transpositions were performed. Data were collected retrospectively. Primary and secondary patency was calculated using life table methods. Complications and interventions were recorded.

Results

Primary patency was 72% at 1 year, 54% at 2 years, and 54% at 3 years. Secondary patency was 95%, 80% and 65% at 1, 2, and 3 years, respectively. Twenty-nine patients experienced complications related to the fistula, and 15 required intervention to maintain patency. Patency was achieved in 100% of the procedures using percutaneous techniques.

Conclusions

This 2-stage procedure should be strongly considered when planning brachial basilic fistulas for hemodialysis access.