Vascular Access Considerations in Home Hemodialysis.

There is a global interest in expanding home dialysis utilization among patients with ESKD. Home hemodialysis (HHD) is an appealing KRT option for this population because of its multiple clinical and quality of life benefits. Central to successful HHD is the establishment and maintenance of a functioning vascular access that serves as a patient's lifeline while on therapy. While the selection of a vascular access type is influenced by individual patient circumstances, the arteriovenous fistula is generally the preferred access method. Training patients to use their dialysis access requires attention to safety, risk management, and monitoring for complications to minimize adverse events and technique failure. Policies incorporating systematic frameworks for quality improvement and assurance, in conjunction with the measurement of metrics relating to vascular access, are tools that should be used by HHD programs to enhance the value of care delivered. In this perspective, we aim to describe what is currently known about the various vascular access options in HHD and to elucidate what needs to be taken into consideration in the selection and care of this access.

Revisiting resistant hypertension: a comprehensive review.

Resistant hypertension (RHT) is typically defined as blood pressure that remains above guideline-directed targets despite the use of three anti-hypertensives, usually including a diuretic, at optimal or maximally tolerated doses. It is generally estimated to affect 10-30% of those diagnosed with hypertension, though the true incidence might be lower after one factor in the prevalence of non-adherence. Risk factors for its development include diabetes, obesity and other adverse lifestyle factors, and a diagnosis of RHT confers a greater risk of adverse cardiovascular outcomes, such as stroke, heart failure and mortality. It is essential to exclude pseudoresistance and secondary hypertension and to ensure non-pharmacologic management is optimised prior to consideration of fourth-line anti-hypertensive agents or advanced interventions, such as device therapies. In this review, we will cover the different definitions of RHT, along with the importance of careful diagnosis and management strategies, and discuss newer agents and research needs.

A Diagnostic Dilemma "Cured" by Dialysis: An Educational Case Report.

Rationale: The differential diagnosis for a patient with high-anion-gap metabolic acidosis (HAGMA) is broad; lactic acidosis is an important entity to screen for and treat. An elevated serum lactate is often used as a marker of inadequate tissue perfusion in critically ill patients but can also be indicative of decreased lactate utilization or poor hepatic clearance. Investigating for the underlying cause such as diabetic ketoacidosis, malignancy, or culprit medications is essential to establish the diagnosis and treatment plan. Presenting concerns of the patient: A 60-year-old man with a history of substance use and end-stage kidney disease treated with hemodialysis presented to hospital with confusion, altered level of consciousness, and hypothermia. Initial laboratory investigations were significant for a severe HAGMA with elevated serum lactate and ß-hydroxybutyrate levels, but toxicology screen was negative, and there was no clear underlying precipitant. Urgent hemodialysis was arranged to mitigate his severe acidosis. Diagnoses: He had an initial single dialysis treatment for 4 hours, with posthemodialysis labs showing significant improvement in his acidosis, serum lactate level, and clinical status (cognition, hypothermia). Given this rapid resolution, a sample from his predialysis blood work was sent for analysis of plasma metformin and returned significantly elevated at 60 mcg/mL (therapeutic range 1-2 mcg/mL). Interventions and outcomes: On careful medication reconciliation in the dialysis unit, the patient stated he had never heard of the medication metformin, and there was no record of a filled prescription at his pharmacy. Given his living situation with shared accommodations, it was presumed that he had taken medications that were prescribed to a roommate. Several of his other medications including his antihypertensives were subsequently given after dialysis on dialysis days to improve adherence. Teaching points: Maintain a broad differential diagnosis for patients presenting with a clinical syndrome consistent with an acute toxicity even if no culprit medications are identifiable on history, especially in patients with a suggestive social history.Anion-gap metabolic acidosis (AGMA) is common in hospitalized patients but sometimes requires further history and/or confirmatory testing to elucidate the root cause underlying typical causes of AGMA such as lactic acidosis or ketoacidosis.The main treatment of metformin toxicity is resuscitation and supportive care; however, metformin's biochemical properties make it readily dialyzable via either diffusion or convection.The Extracorporeal Treatments In Poisoning group recommends hemodialysis for metformin toxicity when there is a serum lactate >20 mmol/L, a blood pH <7.0, a failure of standard therapy, end-organ damage (hepatic or renal insufficiency), or a decreased level of consciousness.

Justification: Le diagnostic différentiel d'un patient présentant une acidose métabolique à trou anionique élevé (AMTAE) est large. L'acidose lactique est une entité importante à dépister et à traiter. Un taux élevé de lactate sérique est fréquemment utilisé comme marqueur d'une perfusion tissulaire inadéquate chez les patients gravement malades, mais il peut également indiquer une utilization réduite du lactate ou une insuffisance hépatique. La recherche de la cause sous-jacente (acidocétose diabétique, malignité ou médicaments responsables) est essentielle pour établir le diagnostic et décider du plan de traitement. Présentation du cas: Un homme de 60 ans atteint d'insuffisance rénale terminale traitée par hémodialyse et ayant des antécédents de toxicomanie qui s'était présenté à l'hôpital confus, avec une altération de l'état de conscience et souffrant d'hypothermie. Les premières analyses de laboratoire ont révélé une grave acidose métabolique à trou anionique élevé et une concentration élevée de lactate sérique et de ß-hydroxybutyrate. Cependant, le bilan toxicologique était négatif et aucun facteur déclenchant sous-jacent clair n'avait été identifié. Une hémodialyse d'urgence a été organisée afin d'atténuer l'acidose. Diagnostic: Le patient a reçu un traitement initial de dialyze pendant quatre heures; les analyses de laboratoire post-hémodialyse ont montré une amélioration significative de l'acidose, du taux de lactate sérique et de l'état clinique (cognition, hypothermie). Vu cette résolution rapide, un échantillon de sang prédialyse a été envoyé pour analyze du taux de metformine plasmatique; cette analyze a révélé un taux significativement élevé de 60 µg/ml (plage thérapeutique: 1-2 µg/ml). Interventions et résultats: Au cours d'une vérification minutieuse de la médication du patient à l'unité de dialyze, ce dernier a déclaré n'avoir jamais entendu parler de metformine; il n'y avait par ailleurs aucune trace d'ordonnance remplie à sa pharmacie pour ce médicament. Étant donné son mode de vie en logements partagés, on a présumé que le patient avait pris des médicaments qui avaient été prescrits à un colocataire. Afin d'améliorer l'observance du traitement, plusieurs des autres médicaments du patient, notamment ses antihypertenseurs, ont par la suite été administrés les jours de dialyze, après la séance. Enseignements tirés: Maintenir un diagnostic différentiel large pour les patients présentant un syndrome clinique compatible avec une intoxication aiguë, et ce, même si aucun médicament responsable n'est identifiable à l'anamnèse, en particulier chez les patients qui ont des antécédents sociaux évocateurs.L'acidose métabolique à trou anionique (AMTA) est fréquente chez les patients hospitalisés, mais nécessite parfois une analyze plus approfondie des antécédents et/ou des tests de confirmations pour parvenir à déterminer la cause fondamentale sous-tendant les causes habituelles de l'AMTA comme l'acidose lactique ou l'acidocétose.Le principal traitement pour contrer la toxicité de la metformine est la réanimation et les traitements de soutien. Les propriétés biochimiques de la metformine la rendent cependant facilement dialysable par diffusion ou convection.Le groupe de travail EXTRIP (EXtracorporeal TReatments In Poisoning) recommande l'hémodialyse pour gérer la toxicité de la metformine en présence d'un taux de lactate sérique supérieur à 20 mmol/L, d'un pH sanguin inférieur à 7, d'un échec du traitement standard, de dommages aux organes cibles (insuffisance hépatique ou rénale) ou d'une altération de l'état de conscience.

Management of Intermittent Hemodialysis in the Critically Ill Patient.

Intermittent hemodialysis remains a cornerstone of extracorporeal KRT in the intensive care unit, either as a first-line therapy for AKI or a second-line therapy when patients transition from a continuous or prolonged intermittent therapy. Intermittent hemodialysis is usually provided 3 days per week in this setting on the basis that no clinical benefits have been demonstrated with more frequent hemodialysis. This should not detract from the importance of continually assessing and refining the hemodialysis prescription (including the need for extra treatments) according to dynamic changes in extracellular volume and other parameters, and ensuring that an adequate dose of hemodialysis is being delivered to the patient. Compared with other KRT modalities, the cardinal challenge encountered during intermittent hemodialysis is hemodynamic instability. This phenomenon occurs when reductions in intravascular volume, as a consequence of ultrafiltration and/or osmotic shifts, outpace compensatory plasma refilling from the extravascular space. Myocardial stunning, triggered by intermittent hemodialysis, and independent of ultrafiltration, may also contribute. The hemodynamic effect of intermittent hemodialysis is likely magnified in patients who are critically ill due to an inability to mount sufficient compensatory physiologic responses in the context of multiorgan dysfunction. Of the many interventions that have undergone testing to mitigate hemodynamic instability related to KRT, the best evidence exists for cooling the dialysate and raising the dialysate sodium concentration. Unfortunately, the evidence supporting routine use of these and other interventions is weak owing to poor study quality and limited sample sizes. Intermittent hemodialysis will continue to be an important and commonly used KRT modality for AKI in patients with critical illness, especially in jurisdictions where resources are limited. There is an urgent need to harmonize the definition of hemodynamic instability related to KRT in clinical trials and robustly test strategies to combat it in this vulnerable patient population.