Healthcare Essentials Quiz

Cell Injury, Acid-Base Balance, and Hemostasis

Cell Injury:

• The cell is the basic unit of the body and has three main components: plasma membrane, nucleus, and cytoplasm.
• Cell injury can be reversible or irreversible and can be caused by hypoxia, physical and chemical agents, microbiological agents, immunological reactions, aging, and nutritional deficiencies.
• Irreversible changes in cell injury affect the cytoplasm and its components, including the mitochondria and cell membrane.
• Free radicals, which have unpaired electrons, can cause cell damage by oxidizing cell components.
• Types of necrosis include coagulative, liquefaction, caseous, fat, and fibrinoid.
• Apoptosis is programmed cell death and is important in destroying cells infected with viruses, damaged DNA, or cancer cells.

Acid-Base Balance:

• Normal plasma pH is 7.35-7.45.
• Acidosis is an abnormal low plasma pH, and alkalosis is an abnormal high plasma pH.
• Buffers, including bicarbonate and non-bicarbonate systems, act as the first line of defense against changes in hydrogen ion concentration.
• The respiratory and renal systems act as the second and third lines of defense, respectively, against changes in body pH.
• There are four basic types of imbalance: metabolic acidosis, metabolic alkalosis, respiratory acidosis, and respiratory alkalosis.
• Compensation for these imbalances can occur through buffering, hyperventilation, and respiratory or renal acid-base control.

Hemostasis:

• Hemostasis is the process of keeping blood clot-free and forming clots at the site of injury.
• The factors responsible for hemostasis include vascular endothelium, platelets, clotting factors, and the fibrinolytic system.
• Disorders of hemostasis can be caused by platelet defects, coagulation defects, excessive fibrinolysis, or vessel wall defects.
• DIC is a thrombo-hemorrhagic disorder caused by rapid consumption of platelets and clotting factors, leading to bleeding and multiple organ failure.