Textbook of Critical Care

Polyuria

Pathophysiology and classification The daily urine output is determined predominantly by the daily intake of fluids, daily solute excretion, and the urine-concentrating ability of the nephrons. The average person excretes about 600–800 mOsm of solutes per day, and average urine…

Pleural effusion in the intensive care unit

Epidemiology Pleural effusions are common in the intensive care unit (ICU). Estimated incidence depends on screening method and ranges from 8% by physical examination to 60% by ultrasound. , Transudative causes of effusion (heart failure, hypoalbuminemia) predominate in the medical…

Pulmonary edema

Background and epidemiology of pulmonary edema Acute pulmonary edema is a commonly occurring emergency that demands immediate medical attention. , It is broadly classified into cardiogenic (increased hydrostatic pressure) or noncardiogenic (increased microvascular permeability) causes; however, it is common for…

Hyperbaric oxygen in critical care

Hyperbaric oxygen (HBO 2 ) treatment involves intermittent breathing of pure oxygen at greater than ambient pressure (>1.4 atmospheres absolute [ATA]). Over the past 20 years, HBO 2 has undergone refinement, with an increased understanding of the mechanisms of action…

Acute respiratory failure

Acute respiratory failure (ARF) is defined by the sudden onset of severe impairment of pulmonary gas exchange and is characterized by the inability of the lungs to meet the body’s metabolic needs for the transport of oxygen (O 2 )…

Arterial hypoxemia

Normal cell function requires an adequate oxygen supply. Lack of oxygen at the cellular level is called hypoxia. Oxygen delivery (DO 2 ) to the tissues is determined by cardiac output and the arterial oxygen content, which in turn is…

Tachycardia and bradycardia

The resting adult heart rate normally ranges from 60 to 100 beats per minute (bpm). Heart rate and rhythm abnormalities occur frequently in critically ill patients, and the incidence of sustained arrhythmias can approach 40% in some intensive care unit…

Low systemic arterial blood pressure

Introduction Assessment of hemodynamics is an important skill in the critical care setting. The goal of hemodynamic monitoring in a critically ill patient is to ensure adequate tissue oxygen delivery and end-organ perfusion. Low systemic arterial blood pressures are commonly…

Very high systemic arterial blood pressure

Hypertensive emergency (HE) is a severe elevation in systemic blood pressure combined with new or progressive end-organ damage most frequently in the cardiac, renal, and central nervous systems. HE is an infrequent clinical presentation of acute hypertension that requires immediate,…

Fever and hyperthermia

“Humanity has but three great enemies: fever, famine and war; of these by far the greatest, by far the most terrible, is fever.” William Osler, from his address to the 47th annual meeting of the American Medical Association, 1896 Fever…