RESUMO
Kidney disease, both acute and chronic, is commonly encountered on the intensive care unit. Due to the role the kidneys play in whole body homeostasis, it follows that their dysfunction has wide-ranging implications and can affect prescribing and therapeutic management. This narrative review discusses the pathophysiology of acute kidney injury and chronic kidney disease, and how this relates to critically unwell patients. We cover several aspects of the management of renal dysfunction on the critical care unit, exploring some of the recurrent themes within the literature, including type and timing of kidney replacement therapy, management of acute kidney injury, as well as discussing how novel biomarkers for acute kidney injury may help to identify patients suffering from acute kidney injury as well as risk stratifying these patients. We discuss how early involvement of specialist nephrology services can improve outcomes in patients with kidney disease as well as offer valuable diagnostic and specialist management advice, particularly for patients with established end stage kidney disease and patients who are already known to nephrology services. We also explore some of the ongoing research questions that need to be answered within this arena.
Assuntos
Injúria Renal Aguda , Falência Renal Crônica , Nefrologia , Insuficiência Renal Crônica , Humanos , Unidades de Terapia Intensiva , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/terapia , Terapia de Substituição Renal , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/terapia , Injúria Renal Aguda/etiologia , Estado Terminal/terapiaRESUMO
Peri-operative acute kidney injury is common, accounting for 30-40% of all in-hospital cases of acute kidney injury. It is associated with clinically significant morbidity and mortality even with what was hitherto regarded as relatively trivial increases in serum creatinine, and carries over a 12-fold relative risk of death following major abdominal surgery. Comorbid conditions such as diabetes, hypertension, liver disease and particularly pre-existing chronic kidney disease, as well as the type and urgency of surgery, are major risk factors for the development of postoperative acute kidney injury. As yet, there are no specific treatment options for the injured kidney, although there are several modifiable risk factors of which the anaesthetist should be aware. As well as the avoidance of potential nephrotoxins and appropriate volume balance, optimal anaesthetic management should aim to reduce the risk of postoperative renal complications. This may include careful ventilatory management and blood pressure control, as well as appropriate analgesic strategies. The choice of anaesthetic agent may also influence renal outcomes. Rather than concentrate on the classical management of acute kidney injury, this review focuses on the potential development of acute kidney injury peri-operatively, and the means by which this may be ameliorated.
Assuntos
Injúria Renal Aguda/etiologia , Anestesia/efeitos adversos , Nefropatias/etiologia , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/mortalidade , Injúria Renal Aguda/terapia , Anestésicos/efeitos adversos , Humanos , Complicações Intraoperatórias/terapia , Nefropatias/mortalidade , Nefropatias/terapia , Complicações Pós-Operatórias/terapia , RiscoRESUMO
INTRODUCTION: A growing body of evidence suggests even small rises in serum creatinine (SCr) are of considerable clinical relevance. Given that participants in endurance events are exposed to potential (repeated) renal insults, a systematic review was undertaken to collate current evidence for acute kidney injury (AKI), complicating such events. METHODS: A systematic review of studies and case reports meeting inclusion criteria on Medline and EMBASE (inception to October 2015). Included: studies with markers of renal function before and after endurance or ultraendurance events; case reports of severe AKI. Two reviewers assessed risk of bias using the Newcastle-Ottawa scale. RESULTS: Eleven case report publications (n=27 individuals) of severe AKI, were retrieved, with risk factors including systemic illness or nephrotoxic medications usually identified. From 30 studies of endurance and ultraendurance events, mean rise in SCr was 29 (±12.3) µmol/L after marathon or ultramarathon (17 studies, n=568 participants) events. Where follow-up tests were conducted, SCr returned to baseline within 48 hours. Rises in biomarkers suggest potential parenchymal insult, rather than simply muscle breakdown. However, evidence of long-term deleterious effects is lacking. CONCLUSIONS: Raised levels of SCr are reported immediately after endurance events. It is not clear whether this is either clinically significant, or if repeated participation predisposes to long-term sequelae. The aetiology of severe exercise-associated AKI is usually multifactorial, with risk factors generally identified in the rare cases reported. On-site biochemistry, urine analysis and biomarkers of AKI may help identify collapsed runners who are at significant short-term risk and allow suitable follow-up.
RESUMO
BACKGROUND: Acute kidney injury (AKI) in the intensive care unit is associated with significant mortality and morbidity. OBJECTIVES: To determine and update previous recommendations for the prevention of AKI, specifically the role of fluids, diuretics, inotropes, vasopressors/vasodilators, hormonal and nutritional interventions, sedatives, statins, remote ischaemic preconditioning and care bundles. METHOD: A systematic search of the literature was performed for studies published between 1966 and March 2017 using these potential protective strategies in adult patients at risk of AKI. The following clinical conditions were considered: major surgery, critical illness, sepsis, shock, exposure to potentially nephrotoxic drugs and radiocontrast. Clinical endpoints included incidence or grade of AKI, the need for renal replacement therapy and mortality. Studies were graded according to the international GRADE system. RESULTS: We formulated 12 recommendations, 13 suggestions and seven best practice statements. The few strong recommendations with high-level evidence are mostly against the intervention in question (starches, low-dose dopamine, statins in cardiac surgery). Strong recommendations with lower-level evidence include controlled fluid resuscitation with crystalloids, avoiding fluid overload, titration of norepinephrine to a target MAP of 65-70 mmHg (unless chronic hypertension) and not using diuretics or levosimendan for kidney protection solely. CONCLUSION: The results of recent randomised controlled trials have allowed the formulation of new recommendations and/or increase the strength of previous recommendations. On the other hand, in many domains the available evidence remains insufficient, resulting from the limited quality of the clinical trials and the poor reporting of kidney outcomes.
Assuntos
Injúria Renal Aguda/prevenção & controle , Injúria Renal Aguda/terapia , Cuidados Críticos/normas , Guias de Prática Clínica como Assunto , Adulto , Idoso , Idoso de 80 Anos ou mais , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Acute kidney injury (AKI) is a frequent complication of critical illness and carries a significant risk of short- and long-term mortality, chronic kidney disease (CKD) and cardiovascular events. The degree of renal recovery from AKI may substantially affect these long-term endpoints. Therefore maximising recovery of renal function should be the goal of any AKI prevention and treatment strategy. Defining renal recovery is far from straightforward due in part to the limitations of the tests available to assess renal function. Here, we discuss common pitfalls in the evaluation of renal recovery and provide suggestions for improved assessment in the future. We review the epidemiology of renal recovery and of the association between AKI and the development of CKD. Finally, we stress the importance of post-discharge follow-up of AKI patients and make suggestions for its incorporation into clinical practice. Summary key points are that risk factors for non-recovery of AKI are age, CKD, comorbidity, higher severity of AKI and acute disease scores. Second, AKI and CKD are mutually related and seem to have a common denominator. Third, despite its limitations full recovery of AKI may best be defined as the absence of AKI criteria, and partial recovery as a fall in AKI stage. Fourth, after an episode of AKI, serial follow-up measurements of serum creatinine and proteinuria are warranted to diagnose renal impairment and prevent further progression. Measures to promote recovery are similar to those preventing renal harm. Specific interventions promoting repair are still experimental.
Assuntos
Injúria Renal Aguda/terapia , Creatinina/sangue , Estado Terminal/terapia , Rim/fisiopatologia , Recuperação de Função Fisiológica , Insuficiência Renal Crônica/terapia , Humanos , Testes de Função RenalRESUMO
OBJECTIVES: Hospital-acquired acute kidney injury (HA-AKI) is associated with a high risk of mortality. Prediction models or rules may identify those most at risk of HA-AKI. This study externally validated one of the few clinical prediction rules (CPRs) derived in a general medicine cohort using clinical information and data from an acute hospitals electronic system on admission: the acute kidney injury prediction score (APS). DESIGN, SETTING AND PARTICIPANTS: External validation in a single UK non-specialist acute hospital (2013-2015, 12â 554 episodes); four cohorts: adult medical and general surgical populations, with and without a known preadmission baseline serum creatinine (SCr). METHODS: Performance assessed by discrimination using area under the receiver operating characteristic curves (AUCROC) and calibration. RESULTS: HA-AKI incidence within 7â days (kidney disease: improving global outcomes (KDIGO) change in SCr) was 8.1% (n=409) of medical patients with known baseline SCr, 6.6% (n=141) in those without a baseline, 4.9% (n=204) in surgical patients with baseline and 4% (n=49) in those without. Across the four cohorts AUCROC were: medical with known baseline 0.65 (95% CIs 0.62 to 0.67) and no baseline 0.71 (0.67 to 0.75), surgical with baseline 0.66 (0.62 to 0.70) and no baseline 0.68 (0.58 to 0.75). For calibration, in medicine and surgical cohorts with baseline SCr, Hosmer-Lemeshow p values were non-significant, suggesting acceptable calibration. In the medical cohort, at a cut-off of five points on the APS to predict HA-AKI, positive predictive value was 16% (13-18%) and negative predictive value 94% (93-94%). Of medical patients with HA-AKI, those with an APS ≥5 had a significantly increased risk of death (28% vs 18%, OR 1.8 (95% CI 1.1 to 2.9), p=0.015). CONCLUSIONS: On external validation the APS on admission shows moderate discrimination and acceptable calibration to predict HA-AKI and may be useful as a severity marker when HA-AKI occurs. Harnessing linked data from primary care may be one way to achieve more accurate risk prediction.
Assuntos
Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/mortalidade , Técnicas de Apoio para a Decisão , Serviço Hospitalar de Emergência/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Injúria Renal Aguda/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Creatinina/sangue , Feminino , Humanos , Testes de Função Renal , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Reino Unido , Adulto JovemRESUMO
Postoperative increases in serum creatinine concentration, by amounts historically viewed as trivial, are associated with increased morbidity and mortality. Acute kidney injury is common, affecting one in five patients admitted with acute medical disease and up to four in five patients admitted to intensive care, of whom one in two have had operations. This review is focused principally on the identification of patients at risk of acute kidney injury and the prevention of injury. In the main, there are no interventions that directly treat the damaged kidney. The management of acute kidney injury is based on correction of dehydration, hypotension, and urinary tract obstruction, stopping nephrotoxic drugs, giving antibiotics for bacterial infection, and commencing renal replacement therapy if necessary.
Assuntos
Injúria Renal Aguda/prevenção & controle , Injúria Renal Aguda/terapia , Assistência Perioperatória/métodos , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/terapia , Injúria Renal Aguda/fisiopatologia , Humanos , Rim/fisiopatologia , Testes de Função Renal , Complicações Pós-Operatórias/fisiopatologia , Terapia de Substituição Renal , Fatores de RiscoRESUMO
BACKGROUND: The Worthing physiological scoring system (PSS) was first validated in 2005 as a tool to predict hospital mortality on admission and was subsequently introduced into clinical practice at Worthing Hospital, UK. Five years on, this study was conducted to determine the effects on mortality and length of stay (LOS) after the introduction of electronic alerting software using the PSS. In addition, we investigated whether the Worthing PSS predictive ability could be improved by addition of further variables. METHODS: Prospective observational study conducted in the acute medical unit, Worthing Hospital, UK. Patient physiological data on admission and discharge/transfer were collected between February and July 2010 from the electronic alerting software VitalPAC™. Patient characteristics, co-morbidity, outcomes, and biochemistry data were taken from the hospital administration and pathology systems. RESULTS: The observed mortality reduction from 8.3% to 5.2% over 5 yr was not statistically significant after adjustment for admission Worthing PSS score. Median LOS was reduced from 4 to 2 days, but this reflected an increase in short stay admissions. Worthing PSS was not significantly improved with the addition of biochemical variables or patient co-morbidity. A score taken before admission to a medical ward showed an improved predictive ability when compared with the initial admission score, but further analysis found no additional clinical benefit. CONCLUSIONS: The introduction of an electronic alerting PSS did not lead to a reduction in mortality when adjusted for severity of illness defined by physiological variables. Predictive performance was not enhanced by the addition of biochemical variables and co-morbidities.
Assuntos
Mortalidade Hospitalar , Tempo de Internação/estatística & dados numéricos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Comorbidade , Interpretação Estatística de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxigenoterapia , Distribuição de Poisson , Valor Preditivo dos Testes , Estudos Prospectivos , Índice de Gravidade de Doença , Software , Análise de Sobrevida , Sobreviventes , Resultado do Tratamento , Reino Unido , Adulto JovemAssuntos
Injúria Renal Aguda/prevenção & controle , Procedimentos Cirúrgicos Cardíacos , Transfusão de Eritrócitos/métodos , Furosemida/administração & dosagem , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Diuréticos/administração & dosagem , Humanos , Período Intraoperatório , Morbidade , Países Baixos/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Taxa de Sobrevida/tendênciasRESUMO
BACKGROUND: Several physiological scoring systems (PSS) have been proposed for identifying those at risk of deterioration. However, the chosen specific physiological values chosen and the scores allocated have not been prospectively validated. In this study, we investigate the relative contributions of the ventilatory frequency, heart rate, arterial pressure, temperature, oxygen saturation, and conscious level to mortality in order to devise a robust scoring system. All data were collected on admission to the emergency unit. Precise 'intervention-calling scores' could then be derived to trigger interventions. METHODS: Our observational, population-based single-centred study took place in a 602-bedded district general hospital. Patients admitted to the emergency care unit at Worthing general hospital during an initial study period between July and November 2003 (n = 3184) and a further validation period between October and November 2005 (n = 1102) were included. RESULTS: Multivariate logistic regression analysis demonstrated that a ventilatory frequency > or = 20 min(-1), heart rate > or =102 min(-1), systolic blood pressure < or = 99 mm Hg, temperature <35.3 degrees C, oxygen saturation < or = 96%, and disturbed consciousness were associated with an increase in mortality. The Worthing PSS was developed from the regression coefficients associated with each variable. The model showed good discrimination with an area under the receiver operating characteristic curve, 0.74, excluding age as a variable. The discrimination of this system was significantly better than the early-warning scoring system. CONCLUSIONS: A simple validated scoring system to predict mortality in medical patients with precise 'intervention-calling scores' has been developed.
Assuntos
Cuidados Críticos/métodos , Indicadores Básicos de Saúde , Monitorização Fisiológica/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Temperatura Corporal , Estado Terminal/terapia , Progressão da Doença , Métodos Epidemiológicos , Feminino , Frequência Cardíaca , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Índice de Gravidade de DoençaRESUMO
Keto-acidosis is usually associated with uncontrolled diabetes and typically poses few diagnostic problems when presenting as hyperglycaemia, metabolic acidosis and a high anion gap. An emaciated patient suffering from Duchenne Muscular Dystrophy and volume depletion presented with acidosis of unknown origin. Preliminary investigations appeared to rule out lactic acidosis, diabetic keto-acidosis and acidosis due to base loss. We have previously reported a technique utilizing liquid chromatography coupled to mass spectrometry (LC-MS) which can be used to characterize the underlying aetiology of acidosis and applied it to ultrafiltrate derived from a blood sample taken from this patient. The anion profile obtained on the chromatogram showed elevated levels of acetoacetate and hydroxybutyrate but no evidence of lactic acidosis, nor was the profile typical of that seen in 'unexplained' acidosis. We concluded that the patient was suffering from keto-acidosis associated with starvation and dehydration, the biochemical features being obscured by both the patient's chronic malnutrition and minimal muscle mass. A combination of enteral feeding and rehydration led to prompt resolution of the patient's metabolic acidosis.
Assuntos
Acidose/etiologia , Desnutrição/complicações , Distrofia Muscular de Duchenne/complicações , Acetoacetatos/sangue , Adolescente , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Cetoacidose Diabética/diagnóstico , Humanos , Hidroxibutiratos/sangue , Corpos Cetônicos/urina , Masculino , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
BACKGROUND: Early and accurate identification of patients who may benefit from aggressive optimal medical intervention is essential if improved outcomes in terms of survival are to be achieved. We studied the usefulness of routine clinical measurements and/or markers of metabolic abnormality in the early identification of those patients at greatest risk of deterioration on presentation to the accident and emergency department. METHODS: We conducted a prospective observational study in the accident and emergency department of a 602-bed district general hospital. Routine clinical measurements (heart rate, systolic blood pressure, temperature, oxygen saturation in room air, level of consciousness and ventilatory frequency) and venous blood analysis for metabolic markers (pH, bicarbonate, standard base excess, lactate, anion gap, strong ion difference, and strong ion gap) and biochemical markers (Na+, K+, Ca2+, Cl-, PO4- albumin, urea and creatinine) were recorded from unselected consecutive hospital admissions over two 3-month periods (September-November 2002 and February-April 2003). RESULTS: Logistic regression analysis showed that neither conventional clinical measurements upon presentation to the accident and emergency department nor venous biochemical and metabolic indices have good discriminatory ability when used as single predictors of either hospital mortality or length of hospital stay. Selecting variables from all the clinical and venous blood measurements gave a parsimonious model containing only age, heart rate, phosphate and albumin (area under the receiver operating characteristic curve, 0.82 [95% CI 0.76, 0.87]). CONCLUSIONS: A combination of clinical and venous biochemical measurements in the accident and emergency department proved the best predictors of hospital mortality. Consequently, they may be helpful as a triage tool in the accident and emergency department to help identify patients at risk of deterioration.
Assuntos
Biomarcadores/sangue , Serviço Hospitalar de Emergência , Triagem/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Estado de Consciência , Tomada de Decisões , Frequência Cardíaca , Mortalidade Hospitalar , Humanos , Tempo de Internação , Modelos Logísticos , Pessoa de Meia-Idade , Prognóstico , Estudos ProspectivosAssuntos
Glicemia , Cuidados Críticos , Dieta , Infarto do Miocárdio/sangue , Biomarcadores , Nutrição Enteral , Humanos , Estado Nutricional , Sepse/terapiaRESUMO
Continuous haemofiltration with lactate-based replacement fluid is widely used for the treatment of acute renal failure (ARF). In the presence of lactic acidosis, such treatment exacerbates rather than improves the clinical state. Continuous haemofiltration using a locally-prepared bicarbonate-based replacement fluid was performed in 200 patients over 7 years. All the patients had ARF with concomitant lactic acidosis, or demonstrated lactate intolerance after starting haemofiltration with lactate-based replacement fluids. In every case it was possible to correct the acidosis without inducing either extracellular volume expansion or hypernatraemia. In 89 patients (45%), the lactic acidosis resolved while being treated with bicarbonate-based haemofiltration. Fifty-seven patients (28.5%) survived. Significant differences at presentation in the group who survived, compared with those who died, were seen in age (50.8 vs. 57.1), mean arterial pressure (68.5 vs. 60.0 mmHg) and APACHE II score (32.1 vs. 38.9). Neither the severity of the presenting acidosis nor the arterial blood lactate appeared to predict outcome. Patients who developed ARF and lactic acidosis after cardiac surgery had a low survival rate. The combination of ARF and lactic acidosis that cannot safely be treated by haemofiltration using lactate-based replacement fluids can be managed with bicarbonate-based haemofiltration.
Assuntos
Acidose Láctica/etiologia , Injúria Renal Aguda/complicações , Injúria Renal Aguda/terapia , Bicarbonatos/uso terapêutico , Hemofiltração/métodos , Acidose Láctica/mortalidade , Acidose Láctica/terapia , Injúria Renal Aguda/mortalidade , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
The acute respiratory distress syndrome continues to be a major medical problem. Despite recent advances in treatment, such as the use of nitrogen monoxide (NO), extracorporeal membrane oxygenation (ECMO) and specialized ventilatory techniques in maintaining adequate oxygenation, mortality still remains high. The presence of activated neutrophils coupled with high inspired oxygen concentrations provide conditions that favour increased oxidative stress and this has focused attention on the possible role of free radical species in both the initiation and propagation of ARDS. Although there is evidence implicating increased free radical activity in ARDS, much of this is from animal models and the role of intervention in such processes has not been established. Although antioxidant therapy has been suggested as a possible treatment for ARDS the current literature is less than convincing. We examine the available data from human studies and suggest possible further studies and future therapeutic goals.