As the site of production of the hormones: renin, erythropoietin and calcitriol that regulate, respectively, blood pressure, erythrocyte (red blood cell) production and absorption of dietary calcium, the kidneys have significant and disparate endocrine function. Additionally, of course, the kidneys have an excretory...

Plasma sodium concentration is normally maintained within the approximate reference range of 135-145 mmol/L. Raised plasma sodium (hypernatremia) is less common than reduced plasma sodium (hyponatremia), and severe hypernatremia (usually defined as plasma sodium >160 mmol/L) is rare but associated with potential for...

As a blood marker of tissue hypoxia, lactate is routinely measured to assess and monitor critically ill patients. Hypoperfusion and resulting tissue hypoxia with evolving lactic acidosis is a common feature of many conditions that render patients critically ill. Tissue hypoxia is by no means the only cause of lactic...

Discussion of acid-base physiology usually focuses mainly on the role of lungs and kidneys, and it is a disease that affects the function of these two organs that are usually invoked when considering, in general terms, acid-base disorders. As the authors of this review article make clear, the liver also plays an...

This paper is an up-to-date account of research and current clinical practice guideline recommendations. Chris Higgins summarizes the recommendations of 2 new guidance documents on the use of natriuretic peptides in heart failure. The first document is a systematic review of published research (up to 2016) on the role ...

The gold standard sample for blood gas analysis is arterial blood. Compared with collection of venous or capillary blood, collection of arterial blood by arterial puncture is a painful procedure that can induce feelings of anxiety. The notion that this pain and anxiety could be a source of preanalytical error in blood ...

Acute kidney injury (AKI) is defined as an abrupt decrease in kidney function evidenced by recent (within 48 hours) increase in serum creatinine concentration equal to or greater than 26.5 µmol/L (0.3 mg/dL). It can be a complication of many conditions that warrant hospital admission so it is common; up to 20 % of...

As the authors of this review article acknowledge, chronic kidney disease (CKD) is a growing public health burden around the world. Recent study, cited by the authors, suggests an estimated 14 % of the US population are now diagnosed with CKD, and 0.2 % have end-stage renal disease (ESRD), the most severe presentation ...

This article discusses the use of a D-dimer assay in excluding venous thromboembolism (VTE) in outpatients. Together with a low pretest probability of VTE, a negative D-dimer test can rule out VTE in 30-50 % of suspected patient cases. The article highlights the importance of using a D-dimer assay with particular...

Monitoring patient acid-base status is one of three principal clinical utilities of blood gas analysis (the other two are monitoring patient oxygen and ventilation status). Three parameters generated during blood gas analysis (pH, pCO₂ and bicarbonate) allow this acid-base assessment and classification of all...