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...

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...

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...

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...

Blood gas analysis, which involves measurement of three parameters: blood pH, pCO₂ and pO₂, is almost unique among routine blood tests in its requirement for arterial blood. All other blood tests are performed on venous blood or occasionally, capillary blood. Collection of arterial blood is technically more demanding ...

Sepsis and septic shock are related consequences of infection that together are a common cause of serious morbidity and high mortality around the world. Survival after sepsis/septic shock depends on rapid diagnosis and treatment with intense monitoring in a critical care unit. Following a 2-year expert appraisal of...

Phototherapy, the standard treatment for neonatal jaundice, is guided by age-related serum bilirubin concentration; the older the baby, the higher is the recommended triggering serum bilirubin concentration. So that for example, UK guidelines state that for a full-term baby who is 12 hours old, phototherapy should be ...

In regulating blood bicarbonate concentration the kidneys play a central role in acid-base homeostasis, and severe renal failure causes metabolic acidosis. This is a disturbance of acid-base characterized by primary reduction in blood bicarbonate and pH, and secondary (compensatory) decrease in pCO₂. One of the aims...