This article evaluates venous blood as an alternative to arterial blood for lactate measurement, highlighting the general considerations related to each of the three types of venous blood which can be used for lactate measurement: peripheral venous blood, central venous blood and mixed venous blood.

Procalcitonin (PCT) is a biomarker which is elevated in bacterial infection. Usefulness of PCT measurements in community-acquired pneumonia (CAP) has to be proven by many studies. A single measurement of PCT on admission or outpatient visits is useful to diagnose CAP, estimate causative pathogens pattern, and for...

It is commonplace for clinical staff tasked with blood sample collection to ask patients to make a fist before venipuncture; it reportedly helps by making veins more visible. Patients may also be asked to maintain a clenched fist during the procedure. This practice of ”fist clenching” is sanctioned in phlebotomy...

Dyspnea (alternative names: breathlessness and shortness of breath) is a common reason for individuals to seek medical help either in primary care or the hospital emergency room. The possible causes are legion, so that assessment of the patient complaining of breathlessness is a common and often difficult diagnostic...

Cardiac arrest, the ultimate medical emergency, is cessation of blood flow to all tissues due to sudden failure of the heart to contract (pump) effectively, evident as absence of a palpable carotid pulse. A major consequential symptom is ineffective or absent breathing and therefore no pulmonary gas exchange. Reduced...

Plasma ionized calcium (iCa) concentration is normally maintained within the approximate range of 1.15-1.33 mmol/L, so that hypocalcemia (reduced plasma ionized calcium concentration) is widely defined as iCa <1.15 mmol/L. Massive blood transfusion is a relatively rare cause of hypocalcemia that is highlighted by this...

This second of two articles on understanding the clinical value of measuring urea concentration explores the clinical value of simultaneous measurement of urea and creatinine and calculating the urea:creatinine ratio. The article discusses the causes of increased and decreased ratio as well as the clinical application ...

Bacterial infections are one of the major reasons for patients presenting to the ED - and the main cause of death in elderly patients. It is important to identify elderly patients with bacterial infections early and initiate treatment in the ED for a better outcome. However, an infection in an elderly patient can be...

In health serum sodium concentration is maintained within the approximate range of 135-145 mmol/L, so that hyponatremia (reduced plasma sodium concentration) is defined as serum sodium Hyponatremia is a frequent complicating feature of common chronic conditions such as heart failure, chronic kidney disease and...

Poisoning by drugs and non-medicinal chemicals can cause a variety of disturbances to acid-base homeostasis, so that the initial emergency room (ER) assessment of poisoned patients often includes arterial blood gas analysis. This recently published clinical study of acid-base disturbances in poisoned patients was...