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PURPOSE OF REVIEW: The purpose of this review is to describe an approach that emphasizes shared decision-making for patients with decompensated cirrhosis and acute kidney injury when liver transplantation is either not an option, or unlikely to be an option. RECENT FINDINGS: When acute kidney injury occurs on a background of decompensated cirrhosis, outcomes are generally poor. Providers can also be faced with prognostic uncertainty. A lack of guidance from nephrology and hepatology professional societies means that providers rely on expert opinion or institutional practice patterns. SUMMARY: For patients who are unlikely to receive liver transplantation, the occurrence of acute kidney injury represents an opportunity for a goals of care conversation. In this article, we share strategies through which providers can incorporate more shared decision-making when caring for these patients. The approach involves creating prognostic consensus amongst multidisciplinary teams and then relying on skilled communicators to share the prognosis. Palliative care consultation can be useful when teams need assistance in the conversations.
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Injúria Renal Aguda , Transplante de Fígado , Nefrologia , Humanos , Diálise Renal , Transplante de Fígado/efeitos adversos , Cirrose Hepática/diagnóstico , Cirrose Hepática/cirurgia , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/terapiaRESUMO
BACKGROUND: Hypercoagulability may be a key mechanism of death in patients with coronavirus disease 2019 (COVID-19). OBJECTIVE: To evaluate the incidence of venous thromboembolism (VTE) and major bleeding in critically ill patients with COVID-19 and examine the observational effect of early therapeutic anticoagulation on survival. DESIGN: In a multicenter cohort study of 3239 critically ill adults with COVID-19, the incidence of VTE and major bleeding within 14 days after intensive care unit (ICU) admission was evaluated. A target trial emulation in which patients were categorized according to receipt or no receipt of therapeutic anticoagulation in the first 2 days of ICU admission was done to examine the observational effect of early therapeutic anticoagulation on survival. A Cox model with inverse probability weighting to adjust for confounding was used. SETTING: 67 hospitals in the United States. PARTICIPANTS: Adults with COVID-19 admitted to a participating ICU. MEASUREMENTS: Time to death, censored at hospital discharge, or date of last follow-up. RESULTS: Among the 3239 patients included, the median age was 61 years (interquartile range, 53 to 71 years), and 2088 (64.5%) were men. A total of 204 patients (6.3%) developed VTE, and 90 patients (2.8%) developed a major bleeding event. Independent predictors of VTE were male sex and higher D-dimer level on ICU admission. Among the 2809 patients included in the target trial emulation, 384 (11.9%) received early therapeutic anticoagulation. In the primary analysis, during a median follow-up of 27 days, patients who received early therapeutic anticoagulation had a similar risk for death as those who did not (hazard ratio, 1.12 [95% CI, 0.92 to 1.35]). LIMITATION: Observational design. CONCLUSION: Among critically ill adults with COVID-19, early therapeutic anticoagulation did not affect survival in the target trial emulation. PRIMARY FUNDING SOURCE: None.
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Anticoagulantes/administração & dosagem , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Transtornos da Coagulação Sanguínea/virologia , COVID-19/complicações , Idoso , Anticoagulantes/efeitos adversos , Transtornos da Coagulação Sanguínea/mortalidade , COVID-19/mortalidade , Estado Terminal , Feminino , Hemorragia/induzido quimicamente , Hemorragia/mortalidade , Hemorragia/virologia , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Taxa de Sobrevida , Estados Unidos/epidemiologia , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/mortalidade , Tromboembolia Venosa/virologiaRESUMO
BACKGROUND: AKI is a common sequela of coronavirus disease 2019 (COVID-19). However, few studies have focused on AKI treated with RRT (AKI-RRT). METHODS: We conducted a multicenter cohort study of 3099 critically ill adults with COVID-19 admitted to intensive care units (ICUs) at 67 hospitals across the United States. We used multivariable logistic regression to identify patient-and hospital-level risk factors for AKI-RRT and to examine risk factors for 28-day mortality among such patients. RESULTS: A total of 637 of 3099 patients (20.6%) developed AKI-RRT within 14 days of ICU admission, 350 of whom (54.9%) died within 28 days of ICU admission. Patient-level risk factors for AKI-RRT included CKD, men, non-White race, hypertension, diabetes mellitus, higher body mass index, higher d-dimer, and greater severity of hypoxemia on ICU admission. Predictors of 28-day mortality in patients with AKI-RRT were older age, severe oliguria, and admission to a hospital with fewer ICU beds or one with greater regional density of COVID-19. At the end of a median follow-up of 17 days (range, 1-123 days), 403 of the 637 patients (63.3%) with AKI-RRT had died, 216 (33.9%) were discharged, and 18 (2.8%) remained hospitalized. Of the 216 patients discharged, 73 (33.8%) remained RRT dependent at discharge, and 39 (18.1%) remained RRT dependent 60 days after ICU admission. CONCLUSIONS: AKI-RRT is common among critically ill patients with COVID-19 and is associated with a hospital mortality rate of >60%. Among those who survive to discharge, one in three still depends on RRT at discharge, and one in six remains RRT dependent 60 days after ICU admission.
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Injúria Renal Aguda/terapia , Injúria Renal Aguda/virologia , COVID-19/complicações , Cuidados Críticos , Terapia de Substituição Renal , Injúria Renal Aguda/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/mortalidade , COVID-19/terapia , Estudos de Coortes , Feminino , Mortalidade Hospitalar , Hospitalização , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Taxa de Sobrevida , Estados Unidos , Adulto JovemRESUMO
Most patients who rely on dialysis for treatment of end-stage renal disease (ESRD) never receive a kidney transplant. Therefore, it is important for nephrology providers to feel comfortable discussing the role of dialysis near the end of life (EOL). Advance care planning (ACP) is an ongoing process of learning patient values and goals in an effort to outline preferences for current and future care. This review presents a framework for how to incorporate ACP in the care of dialysis patients throughout the kidney disease course and at the EOL. Early ACP is useful for all dialysis patients and should ideally begin in the absence of clinical setbacks. Check-in conversations can be used to continue longitudinal discussions with patients and identify opportunities for symptom management and support. Lastly, triggered ACP is useful to clarify care preferences for patients with worsening clinical status. Practical tools include prognostication models to identify patients at risk for decline; ACP documents to operationalize patient care preferences; and communication guidance for engaging in these important conversations. Interdisciplinary teams with expertise from social work, palliative care, and hospice can be helpful at various stages and are discussed here.
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Planejamento Antecipado de Cuidados/organização & administração , Falência Renal Crônica/terapia , Qualidade de Vida , Diálise Renal/métodos , Assistência Terminal/organização & administração , Comunicação , Feminino , Humanos , Falência Renal Crônica/mortalidade , Masculino , Cuidados Paliativos/métodos , Equipe de Assistência ao Paciente/organização & administração , Relações Médico-Paciente , Diálise Renal/efeitos adversos , Medição de Risco , Estados UnidosRESUMO
BACKGROUND: Dialysis is often initiated in the hospital during episodes of acute kidney injury and critical illness. Little is known about how patients or their surrogate decision makers feel about dialysis initiation in the inpatient setting. METHODS: We conducted a prospective cohort study at a large academic center in the United States. All patients who initiated dialysis during a 30-day period in 2016 were approached for enrollment. Study participants were defined as individuals who provided consent for dialysis initiation - either the patient or a surrogate decision-maker. Decisional satisfaction and the degree of shared decision-making were assessed using the decisional attitude scale and the control preferences scale, respectively. These scales were incorporated into a study questionnaire along with an exploratory structured interview. RESULTS: A total of 31 potential participants were eligible and 21 agreed to participate in the study. Continuous renal replacement therapy was used in 14 out of 21 cases (67%) and there was 33% in-hospital mortality in the study cohort. A majority (62%) of patients were unable to participate in the consent process for dialysis initiation and had to rely on a surrogate decision-maker. The mean score for the decisional attitude scale was 4.1 (95% CI 3.8-4.3) with a score of 5 corresponding to high decisional satisfaction. Most of the decisions were classified as shared and incorporated input from clinicians as well as patients or surrogates. Although 90% of participants agreed that they had a choice in making the decision, 81% were unable to mention any alternatives to dialysis initiation. CONCLUSIONS: Dialysis initiation was associated with high decisional satisfaction and most participants felt that the decision incorporated input from patients and providers. However, inpatient dialysis initiation was commonly associated with loss of decisional capacity and reliance on a surrogate decision-maker. This finding is likely driven by critical illness. Survivors of critical illness who remain dialysis dependent may need to revisit conversations about the rationale, risks, and benefits of dialysis.
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Injúria Renal Aguda/terapia , Cuidadores/tendências , Tomada de Decisões , Hospitalização/tendências , Percepção , Diálise Renal/tendências , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/psicologia , Idoso , Cuidadores/psicologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Diálise Renal/psicologiaRESUMO
Hypermagnesemia is an uncommon electrolyte abnormality, due to the fact that magnesium toxicity is only seen in the setting of a massive exposure to exogenous magnesium, often in the setting of renal insufficiency. Here, we report a case of severe hypermagnesemia that resulted in complete paralysis that was secondary to Renacidin administration, a rarely used agent used for intra-renal pelvic or intra-vesicular instillation dissolution of struvite stones. The patient also had concurrent acute kidney injury (AKI). The patient's magnesium was as high as 16.7 mg/dL, and he initially received hemodialysis followed by continuous venovenous hemodialysis. These therapies resulted in a rapid reduction in magnesium levels and eventual resolution of the muscular weakness. The case discussion highlights several key aspects of magnesium homeostasis, the limited mechanistic understanding of Renacidin-induced hypermagnesemia, and the role of renal replacement therapies in the treatment of hypermagnesemia.
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Citratos/efeitos adversos , Magnésio/sangue , Magnésio/toxicidade , Diálise Renal , Injúria Renal Aguda , Adulto , Humanos , Masculino , Doenças Metabólicas/induzido quimicamente , Paralisia/induzido quimicamenteRESUMO
Epilepsy is a disorder with an approximate worldwide prevalence of 1%. Due to complexities of metabolism, protein-binding, renal elimination, and other pharmacokinetic parameters, the dosing of antiepileptic drugs (AEDs) in patients with chronic kidney disease (CKD) or end stage renal disease (ESRD) deserves special attention. This is a review of the most commonly prescribed AEDs with special focus on their indication, pharmacokinetics, and unique considerations for use in patients with CKD and ESRD. A review of their renal toxicities is also included.
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Anticonvulsivantes/uso terapêutico , Epilepsia/complicações , Epilepsia/tratamento farmacológico , Insuficiência Renal Crônica/complicações , Humanos , Falência Renal Crônica/complicaçõesRESUMO
BACKGROUND: Acute kidney injury is common in hospitalized patients, increases morbidity and mortality, and is under-recognized. To improve provider recognition, we previously developed an electronic alert system for acute kidney injury. To test the hypothesis that this electronic acute kidney injury alert could improve patient outcome, we designed a randomized controlled trial to test the effectiveness of this alert in hospitalized patients. The study design presented several methodologic, ethical, and statistical challenges. PURPOSE: To highlight the challenges faced and the solutions employed in the design and implementation of a clinical trial to determine whether the provision of an early electronic alert for acute kidney injury would improve outcomes in hospitalized patients. Challenges included how to randomize the delivery of the alert system and the ethical framework for waiving informed consent. Other methodologic challenges included the selection and statistical evaluation of our study outcome, a ranked-composite of a continuous covariate (creatinine) and two dichotomous outcomes (dialysis and death), and the use of the medical record as a source of trial data. METHODS: We have designed a randomized trial to assess the effectiveness of an electronic alert system for acute kidney injury. With broad inclusion criteria, and a waiver of informed consent, we enroll and randomize virtually every patient with acute kidney injury in our hospital. RESULTS: As of 31 March 2014, we have enrolled 2373 patients of 2400 targeted. Pre-alert data demonstrated a strong association between severity of acute kidney injury and inpatient mortality with a range of 6.4% in those with mild, stage 1 acute kidney injury, to 29% among those with stage 3 acute kidney injury (p < 0.001). We judged that informed consent would undermine the scientific validity of the study and present harms that are out of proportion to the very low risk intervention. CONCLUSION: Our study demonstrates the feasibility of designing an ethical randomized controlled trial of an early electronic alert for acute kidney injury without obtaining informed consent from individual participants. Our study outcome may serve as a model for other studies of acute kidney injury, insofar as our paradigm accounts for the effect that early death and dialysis have on assessment of acute kidney injury severity as defined by maximum achieved serum creatinine.
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Injúria Renal Aguda/diagnóstico , Creatinina/sangue , Registros Eletrônicos de Saúde , Hospitalização , Injúria Renal Aguda/sangue , Método Duplo-Cego , Processamento Eletrônico de Dados , Humanos , Avaliação de Resultados em Cuidados de SaúdeRESUMO
AIMS: Modification of the mortality risk associated with acute kidney injury (AKI) necessitates recognition of AKI when it occurs. We sought to determine whether formal documentation of AKI in the medical record, assessed by billing codes for AKI, would be associated with improved clinical outcomes. METHODS: Retrospective cohort study conducted at three hospitals within a single university health system. Adults without severe underlying kidney disease who suffered in-hospital AKI as defined by a doubling of baseline creatinine (n = 5,438) were included. Those whose AKI was formally documented according to discharge billing codes were compared to those without such documentation in terms of 30-day mortality. RESULTS: Formal documentation of AKI occurred in 2,325 patients (43%). Higher baseline creatinine, higher peak creatinine, medical admission status, and higher Sequential Organ Failure Assessment (SOFA) score were strongly associated with documentation of AKI. After adjustment for severity of disease, formal AKI documentation was associated with reduced 30-day mortality - OR 0.81 (0.68 - 0.96, p = 0.02). Patients with formal documentation were more likely to receive a nephrology consultation (31% vs. 6%, p < 0.001) and fluid boluses (64% vs. 45%, p < 0.001), and had a more rapid discontinuation of angiotensin-converting enzyme inhibitor and angiotensin-receptor blocker medications (HR 2.04, CI 1.69 - 2.46, p < 0.001). CONCLUSIONS: Formal documentation of AKI is associated with improved survival after adjustment for illness severity among patients with creatinine-defined AKI.
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Injúria Renal Aguda/mortalidade , Documentação , Injúria Renal Aguda/sangue , Injúria Renal Aguda/tratamento farmacológico , Adulto , Idoso , Estudos de Coortes , Creatinina/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Background: Patients with CKD have high symptom burden, low rates of advance care planning (ACP), and frequently receive care that is not goal concordant. Improved integration of palliative care into nephrology and access to active medical management without dialysis (AMMWD) have the potential to improve outcomes through better symptom management and enhanced shared decision making. Methods: We describe the development of a kidney palliative care (KPC) clinic and how palliative care practices are integrated within an academic nephrology clinic. We performed a retrospective electronic health record (EHR) review for patients seen in this clinic between January 2015 and February 2019 to describe key clinical activities and delivery of AMMWD. Results: A total of 165 patients were seen in the KPC clinic (139 with CKD and 26 who were already receiving dialysis). Fatigue, mobility issues, and pain were the three most prevalent symptoms (85%, 66%, 58%, respectively). Ninety-one percent of patients had a surrogate decision maker documented in the EHR; 87% of patients had a goals-of-care conversation documented in the EHR. Of the 139 patients with CKD, 67 (48%) chose AMMWD as their disease progressed. Sixty-eight percent (41 of 60) of patients who died during the study were referred to hospice. Conclusions: Our findings suggest that the integration of palliative care into nephrology can assist in identification of symptoms, lead to high rates of ACP, and provide a mechanism for patients to choose and receive AMMWD. The percentage of patients choosing AMMWD in our study suggests that increased shared decision making may lower rates of dialysis initiation in the United States. Additional prospective research and registries for assessing the effects of AMMWD have the potential to improve care for people living with CKD.
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Falência Renal Crônica , Diálise Renal , Humanos , Estados Unidos , Cuidados Paliativos , Estudos Retrospectivos , Estudos Prospectivos , RimRESUMO
INTRODUCTION: Given the burdens of treatment and poor prognosis, older adults with kidney failure would benefit from improved decision making and palliative care to clarify goals, address symptoms, and reduce unwanted procedures. Best Case/Worst Case (BC/WC) is a communication tool that uses scenario planning to support patients' decision making. This article describes the protocol for a multisite, cluster randomised trial to test the effect of training nephrologists to use the BC/WC communication tool on patient receipt of palliative care, and quality of life and communication. METHODS AND ANALYSIS: We are enrolling attending nephrologists, at 10 study sites in the USA, who see outpatients with advanced chronic kidney disease considering dialysis. We aim to enrol 320 patients with an estimated glomerular filtration rate of ≤24 mL/min/1.73 m2 who are age 60 and older and have a predicted survival of 18 months or less. Nephrologists will be randomised in a 1:1 ratio to receive training to use the communication tool (intervention) at study initiation or after study completion (wait-list control). Patients in the intervention group will receive care from a nephrologist trained to use the BC/WC communication tool. Patients in the control group will receive usual care. Using chart review and surveys of patients and caregivers, we will test the efficacy of the BC/WC intervention with receipt of palliative care as the primary outcome. Secondary outcomes include intensity of treatment at the end of life, the effect of the intervention on quality of communication (QOC) between nephrologists and patients (using the QOC scale), the change in quality of life (using the Functional Assessment of Chronic Illness Therapy-Palliative Care scale) and receipt of dialysis. ETHICS AND DISSEMINATION: Approvals have been granted by the Institutional Review Board at the University of Wisconsin (ID: 2022-0193), with each study site ceding review to the primary IRB. All nephrologists will be consented and given a copy of the consent form. No patients or caregivers will be recruited or consented until their nephrology provider has chosen to participate in the study. Results will be disseminated via submission for publication in a peer-reviewed journal and at national meetings. TRIAL REGISTRATION NUMBER: NCT04466865.
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Qualidade de Vida , Insuficiência Renal , Humanos , Idoso , Pessoa de Meia-Idade , Diálise Renal , Cuidados Paliativos/métodos , Comunicação , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
INTRODUCTION: Older patients with advanced chronic kidney disease (CKD) often are inadequately prepared to make informed decisions about treatments including dialysis and cardiopulmonary resuscitation. Further, evidence shows that patients with advanced CKD do not commonly engage in advance care planning (ACP), may suffer from poor quality of life, and may be exposed to end-of-life care that is not concordant with their goals. We aim to study the effectiveness of a video intervention on ACP, treatment preferences and other patient-reported outcomes. METHODS AND ANALYSIS: The Video Images about Decisions for Ethical Outcomes in Kidney Disease trial is a multi-centre randomised controlled trial that will test the effectiveness of an intervention that includes a CKD-related video decision aid followed by recording personal video declarations about goals of care and treatment preferences in older adults with advancing CKD. We aim to enrol 600 patients over 5 years at 10 sites. ETHICS AND DISSEMINATION: Regulatory and ethical aspects of this trial include a single Institutional Review Board mechanism for approval, data use agreements among sites, and a Data Safety and Monitoring Board. We intend to disseminate findings at national meetings and publish our results. TRIAL REGISTRATION NUMBER: NCT04347629.
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Planejamento Antecipado de Cuidados , Insuficiência Renal Crônica , Assistência Terminal , Idoso , Humanos , Estudos Multicêntricos como Assunto , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Diálise Renal , Insuficiência Renal Crônica/terapiaRESUMO
Protein phosphorylation is an important component of vasopressin signaling in the renal collecting duct, but the database of known phosphoproteins is incomplete. We used tandem mass spectrometry to identify vasopressin-regulated phosphorylation events in isolated rat inner medullary collecting duct (IMCD) suspensions. Using multiple search algorithms to identify the phosphopeptides from spectral data, we expanded the size of the existing collecting duct phosphoproteome database from 367 to 1187 entries. Label-free quantification in vasopressin- and vehicle-treated samples detected a significant change in the phosphorylation of 29 of 530 quantified phosphopeptides. The targets include important structural, regulatory, and transporter proteins. The vasopressin-regulated sites included two known sites (Ser-486 and Ser-499) present in the urea channel UT-A1 and one previously unknown site (Ser-84) on vasopressin-sensitive urea channels UT-A1 and UT-A3. In vitro assays using synthetic peptides showed that purified protein kinase A (PKA) could phosphorylate all three sites, and immunoblotting confirmed the PKA dependence of Ser-84 and Ser-486 phosphorylation. These results expand the known list of collecting duct phosphoproteins and highlight the utility of targeted phosphoproteomic approaches.
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Túbulos Renais Coletores/metabolismo , Fosfoproteínas/metabolismo , Proteômica , Vasopressinas/metabolismo , Algoritmos , Animais , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Desamino Arginina Vasopressina/farmacologia , Túbulos Renais Coletores/efeitos dos fármacos , Modelos Animais , Fosfoproteínas/genética , Fosforilação , Ratos , Ratos Brattleboro , Ratos Sprague-Dawley , Transdução de Sinais , beta Catenina/metabolismoRESUMO
Specialty palliative care (PC) clinicians are frequently asked to discuss prognosis with patients and their families. When conveying information about prognosis, PC clinicians need also to discuss the likelihood of prolonged hospitalization, cognitive and functional disabilities, and death. As PC moves further and further upstream, it is crucial that PC providers have a broad understanding of curative and palliative treatments for serious diseases and can collaborate in prognostication with specialists. In this article, we present 10 tips for PC clinicians to consider when caring and discussing prognosis for the seriously ill patients along with their caregivers and care teams. This is the second in a three-part series around prognostication in adult and pediatric PC.
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Enfermagem de Cuidados Paliativos na Terminalidade da Vida , Hepatopatias , Adulto , Criança , Estado Terminal , Humanos , Rim , Cuidados PaliativosRESUMO
Many patients with chronic kidney disease (CKD) and end-stage renal disease have unmet palliative care (PC) needs. Physical and emotional symptoms are common. Some, like uremia and fluid overload, improve with dialysis, but the increasing age of patients initiating renal replacement therapy leaves many untreatable comorbidities like dementia and frailty to negatively impact quality of life. Written by nephrologists and PC clinicians, this article will help PC providers to have a richer understanding of kidney disease-related symptom burden, disease trajectory, prognosis, and barriers to hospice enrollment for patients with CKD and end-stage renal disease.
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Falência Renal Crônica/terapia , Nefrologistas , Cuidados Paliativos , Equipe de Assistência ao Paciente , Tomada de Decisões , Humanos , Prognóstico , Qualidade de VidaAssuntos
Cuidados Paliativos , Diálise Renal , Injúria Renal Aguda , Humanos , Falência Renal CrônicaRESUMO
BACKGROUND AND OBJECTIVES: Data from several countries suggest a recent world-wide increase in the prevalence of stone disease. However, these studies have not analyzed the effect that increases in utilization of imaging modalities have had on detection of asymptomatic stones. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A retrospective chart review of all patients who had an abdominal or retroperitoneal ultrasound in 2005 at a Department of Veterans' Affairs Medical Center was conducted. The charts of patients who had ultrasounds demonstrating kidney stones were further reviewed. Patients were classified into symptomatic and asymptomatic groups on the basis of their clinical history. Age and sex for all patients were recorded. For those patients with stones, additional data were recorded. Of all patients in the study, the percentage of those with asymptomatic stones was calculated. Taking into account uncertainty about symptomaticity in some patients, a sensitivity analysis for the presence or absence of gross and microhematuria was performed to determine a range for the percent of asymptomatic stones. Appropriate statistical tests were used to determine significance. RESULTS: The prevalence of all kidney stones in the study group was 8.6 %. Using the sensitivity analysis, 29.8 to 45.7% of all stones were asymptomatic. Of stones found on abdominal ultrasounds, 71.4% were asymptomatic, whereas 36.8% of stones found on retroperitoneal ultrasound were asymptomatic. CONCLUSIONS: Asymptomatic stones have a relatively high prevalence on ultrasound. Epidemiologic estimates of prevalence of nephrolithiasis need to account for increases in utilization of imaging modalities and the resulting detection bias.