Body fluids can be divided into intracellular and extracellular fluid, depending on their location relative to the cell membrane (see Fig. 1-1).1 Approximately two-thirds of the total body fluid in…

Maternal Physiology Physiologic Changes during Pregnancy and Delivery During pregnancy and the peripartum period, substantial changes in maternal anatomy and physiology occur secondary to changes in hormone activity, increased maternal…

Severely injured patients, burn patients, and those with sepsis often are hypermetabolic, so directed nutritional support within 24 to 48 hours of admission may be beneficial. For example, energy requirements…

Without sufficient insulin, transport of glucose across certain cell membranes slows markedly to cause hyperglycemia. The formation of glucose from protein accounts for the discovery that glucose in urine may…

Short-acting β2 agonists bind to the β2-adrenergic receptor located on the plasma membrane of smooth muscle cells, epithelial, endothelial, and many other types of airway cells.11 This causes a stimulatory…

The motor unit is the functional contractile unit and is composed of a single myelinated α motor neuron and all muscle fibers that receive innervation from this single neuron. Motor…

Intravenous Fluid Types Crystalloids Crystalloids are fluid solutions containing ion salts and other low-molecular-weight substances. Crystalloids can be categorized based on their tonicity or osmotic pressure of the solution with…

Blood products are administered as therapeutic agents in perioperative management. Despite guidelines, most physicians either have not read the guidelines or have difficulty following them. Clinicians often resort to empiric…

Standardization of heparin potency is based on in vitro comparison with a known standard. A unit of heparin is defined as the volume of heparin-containing solution that will prevent 1…

o2 = CO × CaO2 where O2 is equal to oxygen delivery, CO represents cardiac output, and CaO2 is the O2 content of arterial blood. In a 70-kg person, oxygen…