Using educational prescriptions to teach medical students evidence-based medicine.

PURPOSE: To evaluate feasibility and impact of evidence-based medicine (EBM) educational prescriptions (EPs) in medical student clerkships. METHODS: Students answered clinical questions during clerkships using EPs, which guide learners through the "four As" of EBM. Epidemiology fellows graded EPs using a rubric. Feasibility was assessed using descriptive statistics and student and fellow end-of-study questionnaires, which also measured impact. In addition, for each EP, students reported patient impact. Impact on EBM skills was assessed by change in EP scores over time and scores on an EBM objective structured clinical exam (OSCE) that were compared to controls from the prior year. RESULTS: 117 students completed 402 EPs evaluated by 24 fellows. Average score was 7.34/9.00 (SD 1.58). 69 students (59%) and 21 fellows (88%) completed questionnaires. Most students thought EPs improved "Acquiring" and "Appraising". Almost half thought EPs improved "Asking" and "Applying". Fellows did not value grading EPs. For 18% of EPs, students reported a "change" or "potential change" in treatment. 56% "confirmed" treatment. EP scores increased by 1.27 (95% CI: 0.81-1.72). There were no differences in OSCE scores between cohorts. CONCLUSIONS: Integrating EPs into clerkships is feasible and has impact, yet OSCEs were unchanged, and research fellows had limitations as evaluators.

Renal dysfunction associated with intra-abdominal hypertension and the abdominal compartment syndrome.

Once considered mostly a postsurgical condition, intra-abdominal hypertension (IAH) and the abdominal compartment syndrome (ACS) are now thought to increase morbidity and mortality in many patients receiving medical or surgical intensive care. Animal data and human observational studies indicate that oliguria and acute kidney injury are early and frequent consequences of IAH/ACS and can be present at relatively low levels of intra-abdominal pressure (IAP). Among medical patients at particular risk are those with septic shock and severe acute pancreatitis, but the adverse effects of IAH may also be seen in cardiorenal and hepatorenal syndromes. Factors predisposing to IAH/ACS include sepsis, large volume fluid resuscitation, polytransfusion, mechanical ventilation with high intrathoracic pressure, and acidosis, among others. Transduction of bladder pressure is the gold standard for measuring intra-abdominal pressure, and several nonsurgical methods can help reduce IAP. The role of renal replacement therapy for volume management is not well defined but may be beneficial in some cases. IAH/ACS is an important possible cause of acute renal failure in critically ill patients and screening may benefit those at increased risk.

Got calcium? Welcome to the calcium-alkali syndrome.

We recommend changing the name of the milk-alkali syndrome to the calcium-alkali syndrome, because the new terminology better reflects the shifting epidemiology and understanding of this disorder. The calcium-alkali syndrome is now the third most common cause of hospital admission for hypercalcemia, and those at greatest risk are postmenopausal or pregnant women. The incidence of the calcium-alkali syndrome is growing in large part as a result of the widespread use of over-the-counter calcium and vitamin D supplements. Advertising for treatment or prevention of osteoporosis has long encouraged this use. Intricate mechanisms mediating the calcium-alkali syndrome depend on interplay among intestine, kidney, and bone. New insights regarding its pathogenesis focus on the key role of calcium-sensing receptors and TRPV5 channels in the modulation of renal calcium excretion. Restoring extracellular blood volume, increasing GFR and calcium excretion, and discontinuing calcium supplementation provide best treatment.

ACR Appropriateness Criteria® Renal Failure.

Renal failure can be divided into acute kidney injury and chronic kidney disease. Both are common and result in increased patient morbidity and mortality. The etiology is multifactorial and differentiation of acute kidney injury from chronic kidney disease includes clinical evaluation, laboratory tests, and imaging. The main role of imaging is to detect treatable causes of renal failure such as ureteral obstruction or renovascular disease and to evaluate renal size and morphology. Ultrasound is the modality of choice for initial imaging, with duplex Doppler reserved for suspected renal artery stenosis or thrombosis. CT and MRI may be appropriate, particularly for urinary tract obstruction. However, the use of iodinated and gadolinium-based contrast should be evaluated critically depending on specific patient factors and cost-benefit ratio. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

KDOQI US commentary on the 2009 KDIGO Clinical Practice Guideline for the Diagnosis, Evaluation, and Treatment of CKD-Mineral and Bone Disorder (CKD-MBD).

This commentary provides a US perspective on the 2009 KDIGO (Kidney Disease: Improving Global Outcomes) Clinical Practice Guideline for the Diagnosis, Evaluation, Prevention, and Treatment of Chronic Kidney Disease-Mineral and Bone Disorder (CKD-MBD). KDIGO is an independent international organization with the primary mission of the promotion, coordination, collaboration, and integration of initiatives to develop and implement clinical practice guidelines for the care of patients with kidney disease. The National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI), recognizing that international guidelines need to be adapted for each country, convened a group of experts to comment on the application and implementation of the KDIGO guideline for patients with CKD in the United States. This commentary puts the KDIGO guideline into the context of the supporting evidence and the setting of care delivered in the United States and summarizes important differences between prior KDOQI guidelines and the newer KDIGO guideline. It also considers the potential impact of a new bundled payment system for dialysis clinics. The KDIGO guideline addresses the evaluation and treatment of abnormalities of CKD-MBD in adults and children with CKD stages 3-5 on long-term dialysis therapy or with a kidney transplant. Tests considered are those that relate to laboratory, bone, and cardiovascular abnormality detection and monitoring. Treatments considered are interventions to treat hyperphosphatemia, hyperparathyroidism, and bone disease in patients with CKD stages 3-5D and 1-5T. Limitations of the evidence are discussed. The lack of definitive clinical outcome trials explains why most recommendations are not of level 1 but of level 2 strength, which means weak or discretionary recommendations. Suggestions for future research highlight priority areas.

ACR Appropriateness Criteria® Recurrent Lower Urinary Tract Infections in Females.

Urinary tract infections (UTIs) in women are common, with an overall lifetime risk over >50%. UTIs are considered recurrent when they follow complete clinical resolution of a previous UTI and are usually defined as at least three episodes of infection within the preceding 12 months. An uncomplicated UTI is classified as a UTI without structural or functional abnormalities of the urinary tract and without relevant comorbidities. Complicated UTIs are those occurring in patients with underlying structural or medical problems. In women with recurrent uncomplicated UTIs, cystoscopy and imaging are not routinely used. In women suspected of having a recurrent complicated UTI, cystoscopy and imaging should be considered. CT urography or MR urography are usually appropriate for the evaluation of recurrent complicated lower urinary tract infections or for women who are nonresponders to conventional therapy, develop frequent reinfections or relapses, or have known underlying risk factors. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Indeterminate Renal Mass.

Renal masses are increasingly detected in asymptomatic individuals as incidental findings. CT and MRI with intravenous contrast and a dedicated multiphase protocol are the mainstays of evaluation for indeterminate renal masses. A single-phase postcontrast dual-energy CT can be useful when a dedicated multiphase renal protocol CT is not available. Contrast-enhanced ultrasound with microbubble agents is a useful alternative for characterizing renal masses, especially for patients in whom iodinated CT contrast or gadolinium-based MRI contrast is contraindicated. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Hematuria.

Hematuria is a common reason for patients to be referred for imaging of the urinary tract. All patients diagnosed with hematuria should undergo a thorough history and physical examination, urinalysis, and serologic testing prior to any initial imaging. Ultrasound, CT, and MRI are the most common imaging modalities used to evaluate hematuria. This document discusses the following clinical scenarios for hematuria: initial imaging of microhematuria without risk factors or history of recent vigorous exercise, or presence of infection, or viral illness, or present or recent menstruation; initial imaging of microhematuria in patients with known risk factors and no history of recent vigorous exercise, or presence of infection, or viral illness, or present or recent menstruation or renal parenchymal disease; initial imaging of microhematuria in the pregnant patient and initial imaging of gross hematuria. Follow-up of normal or abnormal findings is beyond the scope of this review. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Lower Urinary Tract Symptoms-Suspicion of Benign Prostatic Hyperplasia.

Lower urinary tract symptoms due to benign prostatic enlargement have a high prevalence in men over 50 years of age. Diagnosis is made with a combination of focused history and physician examination and validated symptom questionnaires. Urodynamic studies can help to differentiate storage from voiding abnormalities. Pelvic ultrasound may be indicated to assess bladder volume and wall thickness. Other imaging modalities, including prostate MRI, are usually not indicated in the initial workup and evaluation of uncomplicated lower urinary tract symptoms from an enlarged prostate. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Accuracy of Acid-Base Diagnoses Using the Central Venous Blood Gas in the Medical Intensive Care Unit.

BACKGROUND: Acid-base disturbances are frequent in critically ill patients. Arterial blood gas (ABG) is the gold standard in the diagnosis of these disturbances, but it is invasive with potential hazards. For patients with a central venous catheter, venous blood gas (VBG) sampling may be an alternative, less-invasive diagnostic tool. However, the accuracy of a central VBG-based acid-base disorder diagnosis compared to an ABG is unknown. The primary objective of this study was to assess the accuracy of a central VBG-based acid-base disorder diagnosis compared to the "gold standard" ABG in critically ill patients. METHODS: This was a study of adult patients in a medical intensive care unit that had simultaneously drawn ABG and central VBG samples. Expert acid-base diagnosticians, all nephrologists, diagnosed the acid-base disorder(s) in each blood gas sample. The central VBG diagnostic accuracy was assessed with percent agreement, sensitivity, and specificity compared to the ABG-based diagnosis. RESULTS: The study involved 23 participants. Overall, the central VBG had 100% sensitivity for metabolic acidosis, metabolic alkalosis, and respiratory acidosis, and lower sensitivity (71%) for respiratory alkalosis, and high percent agreement, ranging from 75 to 94%. VBG-based diagnoses in vasopressor-dependent patients (n = 13, 56.5%) performed similarly to the entire sample. CONCLUSIONS: In critically ill adult patients, central VBG may be used to detect and diagnose acid-base disturbances with reasonable diagnostic accuracy, even in shock states, compared to the ABG. This study supports the use of central VBG for diagnosis of acid-base disturbances in critically ill patients.

ACR Appropriateness Criteria® Acute Pyelonephritis.

Pyelonephritis refers to infection involving the renal parenchyma and renal pelvis. In most patients, uncomplicated pyelonephritis is diagnosed clinically and responds quickly to appropriate antibiotic treatment. If treatment is delayed, the patient is immunocompromised, or for other reasons, microabscesses that form during the acute phase of pyelonephritis may coalesce, forming a renal abscess. Patients with underlying diabetes are more vulnerable to complications, including emphysematous pyelonephritis in addition to abscess formation. Additionally, diabetics may not have the typical flank tenderness that helps to differentiate pyelonephritis from a lower urinary tract infection. Additional high-risk populations may include those with anatomic abnormalities of the urinary tract, vesicoureteral reflux, obstruction, pregnancy, nosocomial infection, or infection by treatment-resistant pathogens. Treatment goals include symptom relief, elimination of infection to avoid renal damage, and identification of predisposing factors to avoid future recurrences. The primary imaging modalities used in patients with pyelonephritis are CT, MRI, and ultrasound. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Renovascular Hypertension.

Renovascular hypertension is the most common type of secondary hypertension and is estimated to have a prevalence between 0.5% and 5% of the general hypertensive population, and an even higher prevalence among patients with severe hypertension and end-stage renal disease, approaching 25% in elderly dialysis patients. Investigation for renal artery stenosis is appropriate when clinical presentation suggests secondary hypertension rather than primary hypertension, when there is not another known cause of secondary hypertension, and when intervention would be carried out if a significant renal artery stenosis were identified. The primary imaging modalities used to screen for renal artery stenosis are CT, MRI, and ultrasound, with the selection of imaging dependent in part on renal function. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Renal Transplant Dysfunction.

Renal transplantation is the treatment of choice in patients with end-stage renal disease because the 5-year survival rates range from 72% to 99%. Although graft survival has improved secondary to the introduction of newer immunosuppression drugs and the advancements in surgical technique, various complications still occur. Ultrasound is the first-line imaging modality for the evaluation of renal transplants in the immediate postoperative period and for long-term follow-up. In addition to depicting many of the potential complications of renal transplantation, ultrasound can also guide therapeutic interventions. Nuclear medicine studies, CT, and MRI are often helpful as complementary examinations for specific indications. Angiography remains the reference standard for vascular complications and is utilized to guide nonsurgical intervention. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer-reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Contrast-induced nephropathy: how it develops, how to prevent it.

No current treatment can reverse or ameliorate contrast-induced nephropathy once it occurs, but prophylaxis is possible. Many preventive measures have failed to show benefits in well-designed, prospective, randomized, double-blinded trials. This review will focus only on the prophylactic strategies that have possible or proven value.

ACR Appropriateness Criteria indeterminate renal mass.

Renal masses are increasingly detected in asymptomatic individuals as incidental findings. An indeterminate renal mass is one that cannot be diagnosed confidently as benign or malignant at the time it is discovered. CT, ultrasonography, and MRI of renal masses with fast-scan techniques and intravenous (IV) contrast are the mainstays of evaluation. Dual-energy CT, contrast-enhanced ultrasonography, PET/CT, and percutaneous biopsy are all technologies that are gaining traction in the characterization of the indeterminate renal mass. In cases in which IV contrast cannot be used, whether because of IV contrast allergy or renal insufficiency, renal mass classification with CT is markedly limited. In the absence of IV contrast, ultrasonography, MRI, and biopsy have some advantages. Owing to the low malignant and metastatic potential of small renal cell carcinomas (≤4 cm in diameter), active surveillance is additionally emerging as a diagnostic strategy for patients who have high surgical risk or limited life expectancy. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 3 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and application by the panel of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Pathogenesis of contrast-induced nephropathy: experimental and clinical observations with an emphasis on the role of osmolality.

Experimental studies suggest that the pathogenesis of contrast media nephrotopathy is due to a combination of renal ischemia and direct tubular epithelial cell toxicity. Clinical studies to date have demonstrated a reduction in clinical contrast nephropathy with the introduction of low-osmolar and, more recently, iso-osmolar contrast media. Numerous experimental studies have examined the role of osmolality per se in the pathogenesis of contrast nephropathy, with conflicting results. Whether iso-osmolar contrast media are the least nephrotoxic iodinated contrast media needs to be determined with large prospective randomized clinical trials.