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61.
62.

Objective:

To evaluate current UK practice of periprocedural haematological management for image-guided procedures in relation to Cardiovascular and Interventional Radiological Society guidelines, which provide recommendations according to bleeding risk of procedures from Category 1 (lowest) to 3 (highest).

Methods:

Survey of practice in UK radiology departments conducted over a 1-year period

Results:

48 radiology departments responded. The percentage of departments that stop antithrombotics pre-procedurally are as follows (for Category 1, 2 and 3, respectively): aspirin (31.3%, 43.8%, 54.2%); clopidogrel (54.2%, 68.8%, 72.9%); therapeutic low-molecular-weight heparin (56.3%, 77.1%, 75.0%). The percentage of departments that perform pre-procedural laboratory testing are as follows (for Category 1, 2 and 3, respectively): international normalized ratio (INR; 81.3%, 95.8%, 93.8%); activated partial thrombin time ratio (APTTR; 60.4%, 75.0%, 93.8%); platelet (77.1%, 91.7%, 95.7%); haemoglobin (70.8%, 85.4%, 87.5%). Mean threshold (standard deviation) of laboratory results for conducting procedures (Level 1, 2 and 3, respectively) are as follows: INR [1.53 (0.197), 1.47 (0.186), 1.47 (0.188)]; APTTR [1.50 (0.392), 1.50 (0.339), 1.48 (0.344)]; platelet count (x103 cells per microlitre) [74.4 (28.7), 79.9 (29.1), 80.5 (29.3)]; haemoglobin (grams per decilitre) [9.05 (1.40), 9.00 (1.33), 8.92 (1.21)]. No department practices conformed to current recommendations for (1) pre-procedural cessation of antithrombotics and (2) pre-procedural laboratory testing. Two (4.2%) department practices conformed to recommendations for thresholds of haematological parameters.

Conclusion:

Current peri-procedural haematological management is variable and often does not conform to existing recommendations. Further research into the impact of this variation in practice on patient outcome is required

Advances in Knowledge:

This study demonstrates wide variation in practice in haematological management for image-guided procedures.Periprocedural haematological management, such as correction of coagulopathy, cessation of antithrombotics and pre-procedural laboratory testing (e.g. for haemoglobin levels and platelet count), is an important consideration for patients undergoing image-guided procedures.1 The challenges of periprocedural haematological management are multifactorial in aetiology. In addition to the increasing range of complex image-guided procedures being performed, the patient population undergoing such procedures may also be complicated.2 Many of these patients have comorbidities requiring antithrombotic therapy, or may have liver and marrow dysfunction, which can affect bleeding risk. Decisions on the optimal periprocedural haematological management are also confounded by the lack of high-level evidence, and existing guidelines within the literature can be variable even for equivalent procedures. For example, in two separate internationally accepted guidelines, the recommended international normalized ratio (INR) for chest drain insertion is <1.5 and <2.0.3,4 There is also limited scope to transfer existing evidence on haematological management from other domains such as open surgery to image-guided interventions. Unlike conventional open surgical procedures where bleeding may be visualized immediately and controlled by direct pressure or vessel ligation, bleeding from image-guided procedures may be difficult to control owing to issues with access and identification.5The lack of high-level evidence is unsurprising, given the potential ethical issues in conducting the necessary studies; it would be difficult to justify the randomization of patients to receiving or not receiving coagulopathy correction prior to undergoing various image-guided procedures for the purpose of research.6 As a result, current evidence is often based on retrospective studies. To address this complex issue, the Society of Interventional Radiology in conjunction with the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) has previously produced guidelines based on existing evidence and expert consensus on periprocedural haematological management for image-guided procedures which are stratified into three categories according to the bleeding risk (4 However, despite the existence of such guidelines, from our experience, significant variation in practice exists between clinicians, even within our own institution.

Table 1.

Society of Interventional Radiology/Cardiovascular and Interventional Radiological Society of Europe consensus guidelines on periprocedural haematological management for image-guided procedures according to category of bleeding risk
Guideline itemGuidance according to category of bleeding risk
 
Category 1 (low risk)Category 2 (intermediate risk)Category 3 (high risk) 
Examples of procedures
 
 VascularVenography, IVC filter, PICC line
Arterial intervention (access size up to 7 French), chemoembolization, uterine fibroid embolizationTIPS 
 Non-vascularThoracentesis, paracentesis, superficial aspiration and biopsy
Intra-abdominal abscess drainage, lung biopsy, percutaneous cholecystostomyRenal biopsy, biliary interventions (new tract), nephrostomy 
Antiplatelet/anticoagulation cessation
 
 Aspirin
Do not withholdDo not withholdWithhold 5-day pre-procedure 
 Clopidogrel
Do not withholdWithhold 5-day pre-procedureWithhold 5-day pre-procedure 
 Therapeutic LMWH
Withhold one-dose pre-procedureWithhold one-dose pre-procedureWithhold for 24 h/up to two doses 
Pre-procedural testing
 
 INR
On warfarin/with liver diseaseAll patientsAll patients 
 APTTR
On unfractionated heparinOn unfractionated heparinOn unfractionated heparin 
 Platelet count
Not routinely recommendedNot routinely recommendedAll patients 
 Haemoglobin
Not routinely recommendedNot routinely recommendedAll patients 
Threshold for correcting parameter/withholding procedure
 
 INR
INR >2.0>1.5 (89% consensus)>1.5 (95% consensus) 
 APTTR
No consensusNo consensus>1.5 times control 
 Platelet count
Transfusion if <50 × 103 μl−1Transfusion if <50 × 103 μl−1Transfusion if <50 × 103 μl−1 
 HaemoglobinNo recommended thresholdNo recommended thresholdNo recommended threshold 
Open in a separate windowAPTTR, activated partial thrombin time ratio; INR, international normalized ratio; IVC, inferior vena cava; LMWH, low-molecular-weight heparin; PICC, peripherally inserted central catheters; TIPS, transjugular intrahepatic portosystemic shunt.Adapted from Patel et al.4The aim of this study was to evaluate current practices of haematological management in patients undergoing image-guided procedures in the UK.  相似文献   
63.
64.
Racial and ethnic disparities are disturbing facets of the American healthcare system that document the reality of unequal treatment. Research consistently shows that patients of color experience poorer quality of care and health outcomes contributing to increased risks and accelerated mortality rates relative to their white counterparts. While initially conceptualized as an approach for increasing the responsiveness of children’s behavioral health care, cultural competence has been adopted as a key strategy for eliminating racial and ethnic health disparities across the healthcare system. However, cultural competence research and practices largely focus on improving provider competencies, while agency and system level approaches for meeting the service needs of diverse populations are given less attention. In this article we offer seven essential strategies for promoting and sustaining organizational and systemic cultural competence. These strategies are to: (1) Provide executive level support and accountability, (2) Foster patient, community and stakeholder participation and partnerships, (3) Conduct organizational cultural competence assessments, (4) Develop incremental and realistic cultural competence action plans, (5) Ensure linguistic competence, (6) Diversify, develop, and retain a culturally competent workforce, and (7) Develop an agency or system strategy for managing staff and patient grievances. For each strategy we offer several recommendations for implementation.  相似文献   
65.
The renin–angiotensin–aldosterone system makes a critical contribution to body fluid homeostasis, and abnormalities in this endocrine system have been implicated in certain forms of hypertension. The peptide hormone angiotensin II (AngII) regulates hydromineral homeostasis and blood pressure by acting on both peripheral and brain targets. In the brain, AngII binds to the angiotensin type 1 receptor (AT1R) to stimulate thirst, sodium appetite and both arginine vasopressin (AVP) and oxytocin (OT) secretion. The present study used an experimental model of endogenous AngII to examine the role of p44/42 mitogen‐activated protein kinase (MAPK) as a signalling mechanism to mediate these responses. Animals were given a combined treatment of furosemide and a low dose of captopril (furo/cap), comprising a diuretic and an angiotensin‐converting enzyme inhibitor, respectively, to elevate endogenous AngII levels in the brain. Furo/cap induced p44/42 MAPK activation in key brain areas that express AT1R, and this effect was reduced with either a centrally administered AT1R antagonist (irbesartan) or a p44/42 MAPK inhibitor (U0126). Additionally, furo/cap treatment elicited water and sodium intake, and irbesartan markedly reduced both of these behaviours. Central injection of U0126 markedly attenuated furo/cap‐induced sodium intake but not water intake. Furthermore, p44/42 MAPK signalling was not necessary for either furo/cap‐ or exogenous AngII‐induced AVP or OT release. Taken together, these results indicate that p44/42 MAPK is required for AngII‐induced sodium appetite but not thirst or neurohypophysial secretion. This result may allow for the discovery of more specific downstream targets of p44/42 MAPK to curb sodium appetite, known to exacerbate hypertension, at the same time as leaving thirst and neurohypophysial hormone secretion undisturbed.  相似文献   
66.
67.
Prevalence of obesity, an established risk factor for many cancers, has increased dramatically over the past 50 years in the United States and across the globe. Relative to normoweight cancer patients, obese cancer patients often have poorer prognoses, resistance to chemotherapies, and are more likely to develop distant metastases. Recent progress on elucidating the mechanisms underlying the obesity?cancer connection suggests that obesity exerts pleomorphic effects on pathways related to tumor development and progression and, thus, there are multiple opportunities for primary prevention and treatment of obesity-related cancers. Obesity-associated alterations, including systemic metabolism, adipose inflammation, growth factor signaling, and angiogenesis, are emerging as primary drivers of obesity-associated cancer development and progression. These obesity-associated host factors interact with the intrinsic molecular characteristics of cancer cells, facilitating several of the hallmarks of cancer. Each is considered in the context of potential preventive and therapeutic strategies to reduce the burden of obesity-related cancers. In addition, this review focuses on emerging mechanisms behind the obesity?cancer link, as well as relevant dietary interventions, including calorie restriction, intermittent fasting, low-fat diet, and ketogenic diet, that are being implemented in preclinical and clinical trials, with the ultimate goal of reducing incidence and progression of obesity-related cancers.  相似文献   
68.
We evaluated two representative microcomputer-based programs for organizing a biomedical literature filing system. With a bibliography of 100 anesthetic references, a series of benchmark tests was developed to measure the speed and accuracy of typical searching, sorting, and formatting tasks. Each program performed the searching tasks accurately and at about the same speed. One program performed sorting without errors, provided the field order of the template used to enter references was unchanged. Both programs used punctuation files, that is, templates for controlling author presentation; punctuation to suit style requirements of individual journals; and order of particular fields, such as publisher and year of publication. Each program was able to format journal, book, and chapter references correctly, but the resulting output required some refining in a word processor. Both require a major time commitment to learn and to create custom punctuation files for journals not included in the predesigned punctuation files. Once mastered, both programs are quite competent at organizing reprints and formatting journal references.  相似文献   
69.
To determine if malabsorption of zinc contributes to the zinc deficiency found in cirrhosis, the absorption of an oral dose of ZnCl2, labeled with65Zn and a nonabsorbed marker51CrCl3, was determined from the ratio of these isotopes in a stool specimen. Average65Zn absorption in 25 alcoholic cirrhotics, 37±17% (sd), was low compared to 55±16% in 31 healthy volunteer controls (P<0.01). In contrast, mean65Zn absorption, 47±11%, in 11 nonalcoholic cirrhotics was not significantly different from the average result in healthy controls. Low65Zn absorption was accompanied by low leukocyte zinc in a subgroup of alcoholic cirrhotics with ascites and/or ascites and encephalopathy, but not in the subgroup in which these clinical features were absent. Thus, low zinc absorption contributes to zinc deficiency in decompensated alcoholic cirrhosis. The failure to find similar abnormalities in nonalcoholic cirrhosis suggests that the long-standing consumption of alcoholic beverages contributes to the malabsorption of zinc.Supported by a grant from the Medical Research Council.  相似文献   
70.

Background

Clubfoot can be treated nonoperatively, most commonly using a Ponseti approach, or surgically, most often with a comprehensive clubfoot release. Little is known about how these approaches compare with one another at longer term, or how patients treated with these approaches differ in terms of foot function, foot biomechanics, or quality-of-life from individuals who did not have clubfoot as a child.

Questions/purposes

We compared (1) focused physical and radiographic examinations, (2) gait analysis, and (3) quality-of-life measures at long-term followup between groups of adult patients with clubfoot treated either with the Ponseti method of nonsurgical management or a comprehensive surgical release through a Cincinnati incision, and compared these two groups with a control group without clubfoot.

Methods

This was a case control study of individuals treated for clubfoot at two separate institutions with different methods of treatment between 1983 to 1987. One hospital used only the Ponseti method and the other mainly used a comprehensive clubfoot release. There were 42 adults (24 treated surgically, 18 treated with Ponseti method) with isolated clubfoot along with 48 healthy control subjects who agreed to participate in a detailed analysis of physical function, foot biomechanics, and quality-of-life metrics.

Results

Both treatment groups had diminished strength and motion compared with the control subjects on physical examination measures; however, the Ponseti group had significantly greater ankle plantar flexion ROM (p < 0.001), greater ankle plantar flexor (p = 0.031) and evertor (p = 0.012) strength, and a decreased incidence of osteoarthritis in the ankle and foot compared with the surgical group. During gait the surgical group had reduced peak ankle plantar flexion (p = 0.002), and reduced sagittal plane hindfoot (p = 0.009) and forefoot (p = 0.008) ROM during the preswing phase compared with the Ponseti group. The surgical group had the lowest overall ankle power generation during push off compared with the control subjects (p = 0.002). Outcome tools revealed elevated pain levels in the surgical group compared with the Ponseti group (p = 0.008) and lower scores for physical function and quality-of-life for both clubfoot groups compared with age-range matched control subjects (p = 0.01).

Conclusions

Although individuals in each treatment group experienced pain, weakness, and reduced ROM, they were highly functional into early adulthood. As adults the Ponseti group fared better than the surgically treated group because of advantages including increased ROM observed at the physical examination and during gait, greater strength, and less arthritis. This study supports efforts to correct clubfoot with Ponseti casting and minimizing surgery to the joints, and highlights the need to improve methods that promote ROM and strength which are important for adult function.

Level of Evidence

Level III, prognostic study.  相似文献   
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