The long-term outcome after acute renal failure

PURPOSE OF REVIEW: Research priorities in critical care are increasingly focusing on long-term outcomes and prognosis for survivors of critical illness. This review will focus on long-term outcomes after acute renal failure. RECENT FINDINGS: Few studies have described the long-term outcomes after acute renal failure. Rates of survival are variable and range from 46 to 74%, 55 to 73%, 57 to 65% and 65 to 70% at 90 days, 6 months, 1 year and 5 years, respectively. All of older age, co-morbid illness, illness severity, septic shock, and renal replacement therapy after cardiac surgery have been associated with reduced survival. Recovery to independence from renal replacement therapy is expected in 60-70% of survivors by 90 days. Health-related quality of life is generally good and perceived as acceptable. Survivors often experience difficulty with mobility and limitations in activities of daily living. Renal replacement therapy is costly and achieves marginal cost-effectiveness in terms of quality-adjusted survival for those with a higher probability of survival. SUMMARY: The long-term survival after acute renal failure is poor. Yet, most survivors recover sufficient function to become independent from renal replacement therapy. While perceived health-related quality of life is good, survivors have a lower health-related quality of life compared with the general population. Further research is needed to explore the relationship between survival, markers of morbidity and costs after acute renal failure.     

Fluid resuscitation and the septic kidney

Acute renal failure is a common complication of sepsis in the critically ill patient. Fluid resuscitation is considered a cornerstone for preservation of function in the septic kidney. This is generally based on the assumption that fluid therapy will restore and maintain adequate renal blood flow. This principle, however, has not yet been formally evaluated in humans. Thus, it remains unclear how fluid therapy may affect renal blood flow in septic acute renal failure. Further, there is new evidence to imply that the choice, timing and amount of fluid used for resuscitation in sepsis may have a direct impact on kidney function. Thus, in this editorial, we consider the relevant literature and more recent insights into the effect of fluid resuscitation on the septic kidney.     

Correspondence between EEG-fMRI and EEG dipole localisation of interictal discharges in focal epilepsy

EEG-fMRI and EEG dipole source localisation are two non-invasive imaging methods that can be applied to the study of the haemodynamic and electrical consequences of epileptic discharges. Using them in combination has the potential to allow imaging with the spatial resolution of fMRI and the temporal resolution of EEG. However, although considerable data are available concerning their concordance in studies involving event-related potentials (ERPs), less is known about how well they agree in epilepsy. To this end, 17 patients were selected from a database of 57 who had undergone an EEG-fMRI scanning session followed by a separate EEG session outside of the scanner. Spatiotemporal dipole modelling was compared with the peak and closest EEG-fMRI activations and deactivations. On average, the dipoles were 58.5 mm from the voxel with the highest positive t value and 32.5 mm from the nearest activated voxel. For deactivations, the corresponding values were 60.8 and 34.0 mm. These values are considerably higher than is generally observed with ERPs, probably as a result of the relatively widespread field, which can lead to artificially deep dipoles, and the occurrence of EEG-fMRI responses remote from the presumed focus of the epileptic activity. The results suggest that EEG and MEG inverse solutions for equivalent current dipole approaches should not be strongly constrained by EEG-fMRI results in epilepsy, and that the use of distributed source modelling will be a more appropriate way of combining EEG-fMRI results with source localisation techniques.     

Evidence-based medicine: classifying the evidence from clinical trials--the need to consider other dimensions

The current approach to assessing the quality of evidence obtained from clinical trials focuses on three dimensions: the quality of the design (with double-blinded randomised controlled trials representing the highest level of such design); the statistical power (beta) and the level of significance (alpha). While these aspects are important, we argue that other significant aspects of trial quality impinge upon the truthfulness of the findings: biological plausibility, reproducibility and generalisability. We present several recent studies in critical care medicine where the design, beta and alpha components of the study are seemingly satisfactory but where the aspects of biological plausibility, reproducibility and generalisability show serious limitations. Accordingly, we argue for more reflection, definition and consensus on these aspects of the evaluation of evidence.     

Contrast-induced nephropathy: epidemiology and prevention

Contrast-induced nephropathy (CIN) is a leading cause of iatrogenic acute kidney failure. Periprocedural CIN results in a greater risk of requiring renal replacement therapy, prolonged hospitalization, excessive health care costs, potential long term kidney impairment and mortality. Identified risk factors for CIN include premorbid chronic kidney disease, diabetes mellitus, congestive heart failure, critical illness and volume of administered contrast media. Prophylactic interventions for the prevention of CIN remain controversial and uncertain. In this review we critically appraise the evidence for prevention of CIN. In general, every attempt should be made to correct underlying volume depletion, discontinue potential nephrotoxins, reverse any acute kidney dysfunction or when not possible, consider delay of procedure or an alternative modality for imaging. A minimum volume of contrast media should be employed, including going left ventriculogram and performing staged procedures if applicable. There are few interventions with quality evidence for reducing the incidence of CIN. procedure hydration and the use of nonionic iso-osmolar contrast media have consistently demonstrated efficacy. For patients at high risk, there is evidence to suggest benefit with N-acetylcysteine. Clinical studies with adenosine antagonists are encouraging; however, further confirmatory trials are required. Based on the available studies, there is inadequate evidence for the routine use of hemofiltration, atrial natriuretic peptides, calcium channel blockers, or prostaglandins. There is no evidence to support prophylaxis with diuretic therapy, forced diuresis, low dose dopamine, fenoldopam, captopril, or endothelin receptor antagonists. Despite recent advances in the epidemiology, pathophysiology and natural history of CIN, few effective prophylactic or therapeutic interventions have conclusively demonstrated evidence for a reduction in CIN incidence and no therapy has proven efficacious once CIN is established.     

A review of the use of beeswax in skincare

Background

Beeswax is a naturally occurring product secreted from worker bees that has varied uses in modern day. In skincare, its function ranges from its role as an occlusive, helping to create a semi-occlusive skin barrier that minimizes transepidermal water loss; as a humectant, locking in hydration; and an emollient to soften and soothe the skin. As a natural substance, its use has been shown to help alleviate symptoms associated with common cutaneous conditions like dermatitis, psoriasis, and overgrowth of normal skin flora.

Aims

In this narrative review, we aim to describe current uses of beeswax in skincare that has been published in the literature.

Materials and methods

A review of beeswax related publications was performed by searching the PubMed database studies.

Results

A total of five clinical studies were included with three studies on animals and two studies in humans.

Discussion

Several studies show the benefits of topical beeswax in supporting the skin barrier.

Conclusion

Beeswax can be a low-cost, natural ingredient for use in products. Further studies with topical beeswax are warranted.