Renal replacement anticoagulant management: Protocol and analysis plan for an observational comparative effectiveness study of linked data sources.

Acute kidney injury is common in critical illness. In patients with severe acute kidney injury, renal replacement therapy is needed to prevent harm from metabolic and electrolyte disturbances and fluid overload. In the UK, continuous renal replacement therapy (CRRT) is the preferred modality, which requires anticoagulation.

Heparin versus citrate anticoagulation for continuous renal replacement therapy in intensive care: the RRAM observational study.

Background: In the UK, 10% of admissions to intensive care units receive continuous renal replacement therapy with regional citrate anticoagulation replacing systemic heparin anticoagulation over the last decade. Regional citrate anticoagulation is now used in > 50% of intensive care units, despite little evidence of safety or effectiveness.

Aim: The aim of the Renal Replacement Anticoagulant Management study was to evaluate the clinical and health economic impacts of intensive care units moving from systemic heparin anticoagulation to regional citrate anticoagulation for continuous renal replacement therapy.

What lies downstream: Cellular oxygen delivery during hemodialysis.

Hemodialysis has been linked to structural and functional damage to vital organs such as the brain and heart, possibly via repetitive intradialytic organ ischemia. There is increasing recognition that tissue ischemia can occur without changes in standard hemodynamic parameters such as blood pressure, leading to interest in more direct assessment of the adequacy of oxygen delivery to tissues. In this article, we discuss our current understanding of what happens to cellular oxygen delivery during hemodialysis: we review the underlying physiology, potential measurement techniques, and the clinical literature to date.

Relationship between renal CD68 infiltrates and the Oxford Classification of IgA nephropathy.

Aims: The Oxford Classification E score (endocapillary hypercellularity) predicts renal functional decline in IgA nephropathy (IgAN) patients free from steroid/immunosuppressive (IS) therapy, but is poorly reproducible. We hypothesise that endocapillary hypercellularity reflects glomerular inflammation and that the presence of CD68-positive cells is a more robust marker of E score.

Methods And Results: CD68-positive cells were quantified in glomeruli and tubulointerstitium in biopsies from 118 IgAN patients, and cell counts were correlated with the criteria of the Oxford Classification, assigned on PAS-stained serial sections.

Cerebral ischemia during hemodialysis-finding the signal in the noise.

Hemodialysis patients have multiple risk factors for small vessel cerebrovascular disease and cognitive dysfunction. Hemodialysis itself may cause clinically significant neurological injury through repetitive cerebral ischemia. However, supporting evidence to date consists of epidemiological associations, expert opinion, and small, single-centre studies of variable methodological quality.

Validation of Modelflow Estimates of Cardiac Output in Hemodialysis Patients.

Volume-clamp technology (e.g. Finometer) has become a popular method of collecting continuous, non-invasive, hemodynamic information during hemodialysis.

Relationship between Hypotension and Cerebral Ischemia during Hemodialysis.

The relationship between BP and downstream ischemia during hemodialysis has not been characterized. We studied the dynamic relationship between BP, real-time symptoms, and cerebral oxygenation during hemodialysis, using continuous BP and cerebral oxygenation measurements prospectively gathered from 635 real-world hemodialysis sessions in 58 prevalent patients. We examined the relationship between BP and cerebral ischemia (relative drop in cerebral saturation >15%) and explored the lower limit of cerebral autoregulation at patient and population levels.

Prognostic value of endocapillary hypercellularity in IgA nephropathy patients with no immunosuppression.

Aim: Interpretation of retrospective clinicopathological studies of IgA nephropathy (IgAN) has been confounded by immunosuppression bias. In published validation studies of the Oxford Classification of IgAN, an average of 33 % of patients received non-randomised steroid and/or cytotoxic therapy. In order to determine the true impact of proliferative lesions on the natural history of IgAN, analysis of patient cohorts that have received no immunosuppression is required.

Circuit life versus bleeding risk: the impact of achieved activated partial thromboplastin time versus achieved filtration fraction.

Whilst prolonging hemofilter (circuit) life, heparin increases bleeding risk. The impact of achieved activated partial thromboplastin time (APTT) on circuit life and bleeding risk has not been assessed in a modern critically ill cohort. Lowering filtration fraction may be an alternative means of prolonging circuit life, but is often overlooked in critical care.

Pitfalls in the management of severe hyponatraemia.

The correction of severe hyponatraemia is complicated by practical and theoretical limitations of formulae used to predict response to treatment, and random errors in the measurement of sodium concentration. We report the case of an elderly woman with a symptomatic serum sodium concentration of 93 mmol/l. Correction of serum sodium unintentionally exceeded conventional targets but, as in the majority of such cases, there were no neurological sequelae.

A case of cocaine-induced basilar artery thrombosis.

Background: A 40-year-old man presented to an emergency department with slurred speech, diplopia and agitation several hours after cocaine use. His level of consciousness rapidly dropped in the hours following presentation.

Investigations: Physical examination, CT scan of the head, cerebral angiography.